Band plans alpha

Adding credits to readme 2
2025-10-31 00:48:11 +01:00 · 2020-08-05 21:13:53 +02:00 · 2020-08-05 14:06:31 +02:00 · 2020-08-05 13:12:30 +02:00 · 2020-08-05 13:11:42 +02:00 · 2020-08-05 13:07:12 +02:00
108 changed files with 45834 additions and 118 deletions
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -50,5 +50,10 @@ if (MSVC)
    target_link_libraries(sdrpp PRIVATE portaudio portaudio_static)
 endif (MSVC)

+# # Copy resource directories
+# if (!MSVC)
+#     add_custom_command(TARGET sdrpp POST_BUILD COMMAND cmake -E copy_directory ${CMAKE_SOURCE_DIR}/res ${CMAKE_BINARY_DIR}/res)
+#     add_custom_command(TARGET sdrpp POST_BUILD COMMAND cmake -E copy_directory ${CMAKE_SOURCE_DIR}/bandplans ${CMAKE_BINARY_DIR}/bandplans)
+# endif (MSVC)

 # cmake .. "-DCMAKE_TOOLCHAIN_FILE=C:/Users/Alex/vcpkg/scripts/buildsystems/vcpkg.cmake" -G "Visual Studio 15 2017 Win64"
--- a/band_colors.json
+++ b/band_colors.json
@@ -0,0 +1,7 @@
+{
+    "broadcast": "#0000FFFF",
+    "amateur": "#FF0000FF",
+    "aviation": "#00FF00FF",
+    "marine": "#00FFFFFF",
+    "military": "#FFFF00FF"
+}
--- a/bandplans/general.json
+++ b/bandplans/general.json
@@ -0,0 +1,267 @@
+{
+    "name": "General",
+    "country_name": "Worldwide",
+    "country_code": "--",
+    "author_name": "Ryzerth",
+    "author_url": "https://github.com/AlexandreRouma",
+    "bands": [
+        {
+            "name": "Long Wave",
+            "type": "broadcast",
+            "start": 148500,
+            "end": 283500
+        },
+        {
+            "name": "Medium Wave",
+            "type": "broadcast",
+            "start": 526500,
+            "end": 1606500
+        },
+        {
+            "name": "Shortwave Broadcast",
+            "type": "broadcast",
+            "start": 2300000,
+            "end": 2468000
+        },
+        {
+            "name": "Shortwave Broadcast",
+            "type": "broadcast",
+            "start": 3200000,
+            "end": 3400000
+        },
+        {
+            "name": "Shortwave Broadcast",
+            "type": "broadcast",
+            "start": 3950000,
+            "end": 4000000
+        },
+        {
+            "name": "Shortwave Broadcast",
+            "type": "broadcast",
+            "start": 4750000,
+            "end": 4995000
+        },
+        {
+            "name": "Shortwave Broadcast",
+            "type": "broadcast",
+            "start": 5005000,
+            "end": 5060000
+        },
+        {
+            "name": "Shortwave Broadcast",
+            "type": "broadcast",
+            "start": 5900000,
+            "end": 6200000
+        },
+        {
+            "name": "Shortwave Broadcast",
+            "type": "broadcast",
+            "start": 7200000,
+            "end": 7450000
+        },
+        {
+            "name": "Shortwave Broadcast",
+            "type": "broadcast",
+            "start": 9400000,
+            "end": 9900000
+        },
+        {
+            "name": "Shortwave Broadcast",
+            "type": "broadcast",
+            "start": 11600000,
+            "end": 12100000
+        },
+        {
+            "name": "Shortwave Broadcast",
+            "type": "broadcast",
+            "start": 13570000,
+            "end": 13870000
+        },
+        {
+            "name": "Shortwave Broadcast",
+            "type": "broadcast",
+            "start": 15100000,
+            "end": 15800000
+        },
+        {
+            "name": "Shortwave Broadcast",
+            "type": "broadcast",
+            "start": 17480000,
+            "end": 17900000
+        },
+        {
+            "name": "Shortwave Broadcast",
+            "type": "broadcast",
+            "start": 18900000,
+            "end": 19020000
+        },
+        {
+            "name": "Shortwave Broadcast",
+            "type": "broadcast",
+            "start": 21450000,
+            "end": 21850000
+        },
+        {
+            "name": "Shortwave Broadcast",
+            "type": "broadcast",
+            "start": 25670000,
+            "end": 26100000
+        },
+        {
+            "name": "FM Broadcast",
+            "type": "broadcast",
+            "start": 87500000,
+            "end": 108000000
+        },
+        {
+            "name": "Air Band VOR/ILS",
+            "type": "aviation",
+            "start": 108000000,
+            "end": 118000000
+        },
+        {
+            "name": "Air Band Voice",
+            "type": "aviation",
+            "start": 118000000,
+            "end": 137000000
+        },
+        {
+            "name": "160m Ham Band",
+            "type": "amateur",
+            "start": 1800000,
+            "end": 2000000
+        },
+        {
+            "name": "80m Ham Band",
+            "type": "amateur",
+            "start": 3500000,
+            "end": 3950000
+        },
+        {
+            "name": "60m Ham Band",
+            "type": "amateur",
+            "start": 5351500,
+            "end": 5366500
+        },
+        {
+            "name": "40m Ham Band",
+            "type": "amateur",
+            "start": 7000000,
+            "end": 7200000
+        },
+        {
+            "name": "30m Ham Band",
+            "type": "amateur",
+            "start": 10100000,
+            "end": 10150000
+        },
+        {
+            "name": "20m Ham Band",
+            "type": "amateur",
+            "start": 14000000,
+            "end": 14350000
+        },
+        {
+            "name": "17m Ham Band",
+            "type": "amateur",
+            "start": 18068000,
+            "end": 18168000
+        },
+        {
+            "name": "15m Ham Band",
+            "type": "amateur",
+            "start": 21000000,
+            "end": 21450000
+        },
+        {
+            "name": "12m Ham Band",
+            "type": "amateur",
+            "start": 24890000,
+            "end": 24990000
+        },
+        {
+            "name": "CB",
+            "type": "amateur",
+            "start": 26960000,
+            "end": 27410000
+        },
+        {
+            "name": "10m Ham Band",
+            "type": "amateur",
+            "start": 28000000,
+            "end": 29750000
+        },
+        {
+            "name": "6m Ham Band",
+            "type": "amateur",
+            "start": 50000000,
+            "end": 54000000
+        },
+        {
+            "name": "2m Ham Band",
+            "type": "amateur",
+            "start": 144000000,
+            "end": 148000000
+        },
+        {
+            "name": "Marine",
+            "type": "marine",
+            "start": 156000000,
+            "end": 162025000
+        },
+        {
+            "name": "1.25m Ham Band",
+            "type": "amateur",
+            "start": 222000000,
+            "end": 225000000
+        },
+        {
+            "name": "Military Air",
+            "type": "military",
+            "start": 225000000,
+            "end": 380000000
+        },
+        {
+            "name": "Military Sat",
+            "type": "military",
+            "start": 240000000,
+            "end": 270000000
+        },
+        {
+            "name": "70cm Ham Band",
+            "type": "amateur",
+            "start": 420000000,
+            "end": 450000000
+        },
+        {
+            "name": "PMR446",
+            "type": "amateur",
+            "start": 446000000,
+            "end": 446200000
+        },
+        {
+            "name": "33cm Ham Band",
+            "type": "amateur",
+            "start": 902000000,
+            "end": 928000000
+        },
+        {
+            "name": "23cm Ham Band",
+            "type": "amateur",
+            "start": 1240000000,
+            "end": 1300000000
+        },
+        {
+            "name": "13cm Ham Band",
+            "type": "amateur",
+            "start": 2300000000,
+            "end": 2310000000
+        },
+        {
+            "name": "13cm Ham Band",
+            "type": "amateur",
+            "start": 2390000000,
+            "end": 2450000000
+        }
+    ]
+}
--- a/bandplans/germany.json
+++ b/bandplans/germany.json
@@ -0,0 +1,141 @@
+{
+    "name": "Germany",
+    "country_name": "Germany",
+    "country_code": "DE",
+    "author_name": "Tobias Mädel",
+    "author_url": "https://tbspace.de",
+    "bands": [
+        {
+            "name": "LW",
+            "type": "amateur",
+            "start": 135700,
+            "end": 137800
+        },
+        {
+            "name": "630m",
+            "type": "amateur",
+            "start": 472000,
+            "end": 479000
+        },
+        {
+            "name": "160m",
+            "type": "amateur",
+            "start": 1810000,
+            "end": 2000000
+        },
+        {
+            "name": "80m",
+            "type": "amateur",
+            "start": 3500000,
+            "end": 3800000
+        },
+        {
+            "name": "60m",
+            "type": "amateur",
+            "start": 5351500,
+            "end": 5366500
+        },
+        {
+            "name": "40m",
+            "type": "amateur",
+            "start": 7000000,
+            "end": 7200000
+        },
+        {
+            "name": "30m",
+            "type": "amateur",
+            "start": 10100000,
+            "end": 10150000
+        },
+        {
+            "name": "20m",
+            "type": "amateur",
+            "start": 14000000,
+            "end": 14350000
+        },
+        {
+            "name": "17m",
+            "type": "amateur",
+            "start": 18068000,
+            "end": 18168000
+        },
+        {
+            "name": "15m",
+            "type": "amateur",
+            "start": 21000000,
+            "end": 21450000
+        },
+        {
+            "name": "12m",
+            "type": "amateur",
+            "start": 24890000,
+            "end": 24990000
+        },
+        {
+            "name": "CB",
+            "type": "other",
+            "start": 26565000,
+            "end": 27405000
+        },
+        {
+            "name": "10m",
+            "type": "amateur",
+            "start": 28000000,
+            "end": 29700000
+        },
+        {
+            "name": "6m",
+            "type": "amateur",
+            "start": 50030000,
+            "end": 51000000
+        },
+        {
+            "name": "4m",
+            "type": "amateur",
+            "start": 70150000,
+            "end": 70200000
+        },
+        {
+            "name": "FM",
+            "type": "broadcast",
+            "start": 87500000,
+            "end": 108000000
+        },
+        {
+            "name": "2m",
+            "type": "amateur",
+            "start": 144000000,
+            "end": 146000000
+        },
+        {
+            "name": "Freenet",
+            "type": "other",
+            "start": 149025000,
+            "end": 149115625
+        },
+        {
+            "name": "70cm",
+            "type": "amateur",
+            "start": 430000000,
+            "end": 440000000
+        },
+        {
+            "name": "PMR446",
+            "type": "other",
+            "start": 446006250,
+            "end": 446196875
+        },
+        {
+            "name": "23cm",
+            "type": "amateur",
+            "start": 1240000000,
+            "end": 1300000000
+        },
+        {
+            "name": "13cm",
+            "type": "amateur",
+            "start": 2320000000,
+            "end": 2450000000
+        }
+    ]
+}
--- a/bandplans/russia.json
+++ b/bandplans/russia.json
@@ -0,0 +1,135 @@
+{
+    "name": "Russia",
+    "country_name": "Russia",
+    "country_code": "RU",
+    "author_name": "Raov",
+    "author_url": "https://twitter.com/raov_birbtog",
+    "bands": [
+        {
+            "name": "160m CW",
+            "type": "amateur",
+            "start": 1810000,
+            "end": 1838000
+        },
+        {
+            "name": "160m NB",
+            "type": "amateur",
+            "start": 1838000,
+            "end": 1840000
+        },
+        {
+            "name": "160m + Digi",
+            "type": "amateur",
+            "start": 1840000,
+            "end": 1843000
+        },
+        {
+            "name": "160m",
+            "type": "amateur",
+            "start": 1843000,
+            "end": 2000000
+        },
+        {
+            "name": "80m CW",
+            "type": "amateur",
+            "start": 3500000,
+            "end": 3510000
+        },
+        {
+            "name": "80m CW Contest",
+            "type": "amateur",
+            "start": 3510000,
+            "end": 3560000
+        },
+        {
+            "name": "80m CW",
+            "type": "amateur",
+            "start": 3560000,
+            "end": 3570000
+        },
+        {
+            "name": "80m NB, Digi 200Hz",
+            "type": "amateur",
+            "start": 3570000,
+            "end": 3580000
+        },
+        {
+            "name": "80m NB, Digi 500Hz",
+            "type": "amateur",
+            "start": 3580000,
+            "end": 3600000
+        },
+        {
+            "name": "80m SSB Contest",
+            "type": "amateur",
+            "start": 3600000,
+            "end": 3650000
+        },
+        {
+            "name": "80m",
+            "type": "amateur",
+            "start": 3650000,
+            "end": 3700000
+        },
+        {
+            "name": "80m SSB Contest",
+            "type": "amateur",
+            "start": 3700000,
+            "end": 3800000
+        },
+        {
+            "name": "60m CW 200Hz",
+            "type": "amateur",
+            "start": 5351500,
+            "end": 5354000
+        },
+        {
+            "name": "60m USB",
+            "type": "amateur",
+            "start": 5354000,
+            "end": 5366000
+        },
+        {
+            "name": "60m CW 20Hz",
+            "type": "amateur",
+            "start": 5356000,
+            "end": 5366500
+        },
+        {
+            "name": "40m CW",
+            "type": "amateur",
+            "start": 7000000,
+            "end": 7040000
+        },
+        {
+            "name": "40m NB, Digi 500Hz",
+            "type": "amateur",
+            "start": 7040000,
+            "end": 7050000
+        },
+        {
+            "name": "40m",
+            "type": "amateur",
+            "start": 7050000,
+            "end": 7060000
+        },
+        {
+            "name": "40m SSB Contest",
+            "type": "amateur",
+            "start": 7060000,
+            "end": 7100000
+        },
+        {
+            "name": "40m",
+            "type": "amateur",
+            "start": 7100000,
+            "end": 7130000
+        },
+        {
+            "name": "40m SSB Contest",
+            "type": "amateur",
+            "start": 7130000,
+            "end": 7200000
+        }
+    ]
+}
--- a/readme.md
+++ b/readme.md
@@ -46,6 +46,7 @@ SDR++ is a cross-platform and open source SDR software with the aim of being blo
 * glew
 * PothosSDR (for libvolk and SoapySDR)

+## The build
 ```
 mkdir build
 cd build
@@ -53,6 +54,10 @@ cmake .. "-DCMAKE_TOOLCHAIN_FILE=C:/Users/Alex/vcpkg/scripts/buildsystems/vcpkg.
 cmake --build . --config Release
 ```

+## Copying over needed directories
+The last step of the build process is copying the `bandplans` and `res` directories to the output directory.
+If you followed the steps above, it should be `build/Release`.
+
 # Building on Linux
 comming soon :)

@@ -61,4 +66,18 @@ comming soon as well :)

 # Contributing
 Feel free to issue pull request and report bugs via the github issues.
-I will soon publish a contributing.md listing the code style to use.
+I will soon publish a contributing.md listing the code style to use.
+
+# Credits
+## Libaries used
+* [SoapySDR (PothosWare)](https://github.com/pothosware/SoapySDR)
+* [ImGui (ocornut)](https://github.com/ocornut/imgui)
+* [spdlog (gabime)](https://github.com/gabime/spdlog)
+* [json (nlohmann)](https://github.com/nlohmann/json)
+* [portaudio (PortAudio community)](http://www.portaudio.com/)
+
+## Contributors
+* [aosync](https://github.com/aosync)
+* [Benjamin Kyd](https://github.com/benkyd)
+* [Tobias Mädel](https://github.com/Manawyrm)
+* [Raov](https://twitter.com/raov_birbtog)
--- a/src/bandplan.cpp
+++ b/src/bandplan.cpp
@@ -0,0 +1,122 @@
+#include <bandplan.h>
+
+namespace bandplan {
+    std::map<std::string, BandPlan_t> bandplans;
+    std::vector<std::string> bandplanNames;
+    std::string bandplanNameTxt;
+    std::map<std::string, BandPlanColor_t> colorTable;
+
+    void generateTxt() {
+        bandplanNameTxt = "";
+        for (int i = 0; i < bandplanNames.size(); i++) {
+            bandplanNameTxt += bandplanNames[i];
+            bandplanNameTxt += '\0';
+        }
+    }
+
+    void to_json(json& j, const Band_t& b) {
+        j = json{
+            {"name", b.name},
+            {"type", b.type},
+            {"start", b.start},
+            {"end", b.end},
+        };
+    }
+
+    void from_json(const json& j, Band_t& b) {
+        j.at("name").get_to(b.name);
+        j.at("type").get_to(b.type);
+        j.at("start").get_to(b.start);
+        j.at("end").get_to(b.end);
+    }
+
+    void to_json(json& j, const BandPlan_t& b) {
+        j = json{
+            {"name", b.name},
+            {"country_name", b.countryName},
+            {"country_code", b.countryCode},
+            {"author_name", b.authorName},
+            {"author_url", b.authorURL},
+            {"bands", b.bands}
+        };
+    }
+
+    void from_json(const json& j, BandPlan_t& b) {
+        j.at("name").get_to(b.name);
+        j.at("country_name").get_to(b.countryName);
+        j.at("country_code").get_to(b.countryCode);
+        j.at("author_name").get_to(b.authorName);
+        j.at("author_url").get_to(b.authorURL);
+        j.at("bands").get_to(b.bands);
+    }
+
+    void to_json(json& j, const BandPlanColor_t& ct) {
+        spdlog::error("ImGui color to JSON not implemented!!!");
+    }
+    
+    void from_json(const json& j, BandPlanColor_t& ct) {
+        std::string col = j.get<std::string>();
+        if (col[0] != '#' || !std::all_of(col.begin() + 1, col.end(), ::isxdigit)) {
+            return;
+        }
+        uint8_t r, g, b, a;
+        r = std::stoi(col.substr(1, 2), NULL, 16);
+        g = std::stoi(col.substr(3, 2), NULL, 16);
+        b = std::stoi(col.substr(5, 2), NULL, 16);
+        a = std::stoi(col.substr(7, 2), NULL, 16);
+        ct.colorValue = IM_COL32(r, g, b, a);
+        ct.transColorValue = IM_COL32(r, g, b, 100);
+    }
+
+    void loadBandPlan(std::string path) {
+        std::ifstream file(path.c_str());
+        json data;
+        data << file;
+        file.close();
+
+        BandPlan_t plan = data.get<BandPlan_t>();
+        if (bandplans.find(plan.name) != bandplans.end()) {
+            spdlog::error("Duplicate band plan name ({0}), not loading.", plan.name);
+            return;
+        }
+        bandplans[plan.name] = plan;
+        bandplanNames.push_back(plan.name);
+        generateTxt();
+    }
+
+    void loadFromDir(std::string path) {
+        if (!std::filesystem::exists(path)) {
+            spdlog::error("Band Plan directory does not exist");
+            return;
+        }
+        if (!std::filesystem::is_directory(path)) {
+            spdlog::error("Band Plan directory isn't a directory...");
+            return;
+        }
+        bandplans.clear();
+        for (const auto & file : std::filesystem::directory_iterator(path)) {
+            std::string path = file.path().generic_string();
+            if (file.path().extension().generic_string() != ".json") {
+                continue;
+            }
+            loadBandPlan(path);
+        }
+    }
+
+    void loadColorTable(std::string path) {
+        if (!std::filesystem::exists(path)) {
+            spdlog::error("Band Plan Color Table file does not exist");
+            return;
+        }
+        if (!std::filesystem::is_regular_file(path)) {
+            spdlog::error("Band Plan Color Table file isn't a file...");
+            return;
+        }
+        std::ifstream file(path.c_str());
+        json data;
+        data << file;
+        file.close();
+
+        colorTable = data.get<std::map<std::string, BandPlanColor_t>>();
+    }
+};
--- a/src/bandplan.h
+++ b/src/bandplan.h
@@ -0,0 +1,51 @@
+#pragma once
+#include <json.hpp>
+#include <fstream>
+#include <spdlog/spdlog.h>
+#include <filesystem>
+#include <sstream>
+#include <iomanip>
+#include <imgui/imgui.h>
+
+using nlohmann::json;
+
+namespace bandplan {
+    struct Band_t {
+        std::string name;
+        std::string type;
+        float start;
+        float end;
+    };
+
+    void to_json(json& j, const Band_t& b);
+    void from_json(const json& j, Band_t& b);
+
+    struct BandPlan_t {
+        std::string name;
+        std::string countryName;
+        std::string countryCode;
+        std::string authorName;
+        std::string authorURL;
+        std::vector<Band_t> bands;
+    };
+
+    void to_json(json& j, const BandPlan_t& b);
+    void from_json(const json& j, BandPlan_t& b);
+
+    struct BandPlanColor_t {
+        uint32_t colorValue;
+        uint32_t transColorValue;
+    };
+
+    void to_json(json& j, const BandPlanColor_t& ct);
+    void from_json(const json& j, BandPlanColor_t& ct);
+    
+    void loadBandPlan(std::string path);
+    void loadFromDir(std::string path);
+    void loadColorTable(std::string path);
+
+    extern std::map<std::string, BandPlan_t> bandplans;
+    extern std::vector<std::string> bandplanNames;
+    extern std::string bandplanNameTxt;
+    extern std::map<std::string, BandPlanColor_t> colorTable;
+};
--- a/src/dsp/resampling.h
+++ b/src/dsp/resampling.h
@@ -144,13 +144,9 @@ namespace dsp {
        }

        void setBlockSize(int blockSize) {
-            printf("%d\n", blockSize);
            if (running) {
                return;
            }
-            if (blockSize < 1 ) {
-                return;
-            }
            _blockSize = blockSize;
            output.setMaxLatency(blockSize * 2);
        }
@@ -159,9 +155,6 @@ namespace dsp {
            if (running) {
                return;
            }
-            if (skip < 0 ) {
-                skip = 0;
-            }
            _skip = skip;
        }

@@ -170,9 +163,20 @@ namespace dsp {
    private:
        static void _worker(BlockDecimator* _this) {
            complex_t* buf = new complex_t[_this->_blockSize];
+            bool delay = _this->_skip < 0;
+
+            int readCount = std::min<int>(_this->_blockSize + _this->_skip, _this->_blockSize);
+            int skip = std::max<int>(_this->_skip, 0);
+            int delaySize = (-_this->_skip) * sizeof(complex_t);
+
+            complex_t* start = &buf[std::max<int>(-_this->_skip, 0)];
+            complex_t* delayStart = &buf[_this->_blockSize + _this->_skip];
+
            while (true) {
-                int read = _this->_input->readAndSkip(buf, _this->_blockSize, _this->_skip);
-                if (read < 0) { break; };
+                if (delay) {
+                    memmove(buf, delayStart, delaySize);
+                }
+                if (_this->_input->readAndSkip(start, readCount, skip) < 0) { break; };
                if (_this->output.write(buf, _this->_blockSize) < 0) { break; };
            }
            delete[] buf;
@@ -238,8 +242,6 @@ namespace dsp {
            _interp = _outputSampleRate / _gcd;
            _decim = inputSampleRate / _gcd;

-            printf("FIRResampler.setInputSampleRate(): %d %d\n", _interp, _decim);
-
            float cutoff = std::min<float>(_outputSampleRate / 2.0f, _inputSampleRate / 2.0f);
            if (passBand > 0.0f && transWidth > 0.0f) {
                dsp::BlackmanWindow(_taps, _inputSampleRate * _interp, passBand, transWidth);
@@ -265,8 +267,6 @@ namespace dsp {
            outputBlockSize = (_blockSize * _interp) / _decim;
            output.setMaxLatency(outputBlockSize * 2);

-            printf("FIRResampler.setOutputSampleRate(): %d %d\n", _interp, _decim);
-
            float cutoff = std::min<float>(_outputSampleRate / 2.0f, _inputSampleRate / 2.0f);
            if (passBand > 0.0f && transWidth > 0.0f) {
                dsp::BlackmanWindow(_taps, _inputSampleRate * _interp, passBand, transWidth);
@@ -327,8 +327,6 @@ namespace dsp {
            int decim = _this->_decim;

            float correction = (float)sqrt((float)interp);
-
-            printf("Resamp: %d %d", inCount, _this->outputBlockSize);
            
            int afterInterp = inCount * interp;
            int outIndex = 0;
@@ -432,8 +430,6 @@ namespace dsp {
            _interp = _outputSampleRate / _gcd;
            _decim = inputSampleRate / _gcd;

-            printf("FloatFIRResampler.setInputSampleRate(): %d %d\n", _interp, _decim);
-
            float cutoff = std::min<float>(_outputSampleRate / 2.0f, _inputSampleRate / 2.0f);
            if (passBand > 0.0f && transWidth > 0.0f) {
                dsp::BlackmanWindow(_taps, _inputSampleRate * _interp, passBand, transWidth);
@@ -459,8 +455,6 @@ namespace dsp {
            outputBlockSize = (_blockSize * _interp) / _decim;
            output.setMaxLatency(outputBlockSize * 2);

-            printf("FloatResampler.setOutputSampleRate(): %d %d\n", _interp, _decim);
-
            float cutoff = std::min<float>(_outputSampleRate / 2.0f, _inputSampleRate / 2.0f);
            if (passBand > 0.0f && transWidth > 0.0f) {
                dsp::BlackmanWindow(_taps, _inputSampleRate * _interp, passBand, transWidth);
@@ -521,8 +515,6 @@ namespace dsp {
            int decim = _this->_decim;

            float correction = (float)sqrt((float)interp);
-
-            printf("FloatResamp: %d %d", inCount, _this->outputBlockSize);
            
            int afterInterp = inCount * interp;
            int outIndex = 0;
--- a/src/dsp/source.h
+++ b/src/dsp/source.h
@@ -73,8 +73,8 @@ namespace dsp {
                    _this->_phase += _this->_phasorSpeed;
                    outBuf[i].i = sin(_this->_phase);
                    outBuf[i].q = cos(_this->_phase);
+                    _this->_phase = fmodf(_this->_phase, 2.0f * 3.1415926535); // TODO: Get a more efficient generator
                }
-                _this->_phase = fmodf(_this->_phase, 2.0f * 3.1415926535);
                if (_this->output.write(outBuf, _this->_blockSize) < 0) { break; };
            }
            delete[] outBuf;
--- a/src/io/audio.h
+++ b/src/io/audio.h
@@ -4,6 +4,7 @@
 #include <dsp/types.h>
 #include <fstream>
 #include <portaudio.h>
+#include <spdlog/spdlog.h>

 namespace io {
    class AudioSink {
@@ -40,9 +41,16 @@ namespace io {
            outputParams.device = Pa_GetDefaultOutputDevice();
            outputParams.suggestedLatency = Pa_GetDeviceInfo(outputParams.device)->defaultLowOutputLatency;
            PaError err = Pa_OpenStream(&stream, NULL, &outputParams, 48000.0f, _bufferSize, paClipOff, _callback, this);
-            printf("%s\n", Pa_GetErrorText(err));
+            if (err != 0) {
+                spdlog::error("Error while opening audio stream: ({0}) => {1}", err, Pa_GetErrorText(err));
+                return;
+            }
            err = Pa_StartStream(stream);
-            printf("%s\n", Pa_GetErrorText(err));
+            if (err != 0) {
+                spdlog::error("Error while starting audio stream: ({0}) => {1}", err, Pa_GetErrorText(err));
+                return;
+            }
+            spdlog::info("Audio device open.");
        }

        void stop() {
--- a/src/io/soapy.h
+++ b/src/io/soapy.h
@@ -1,13 +1,16 @@
 #include <string>
 #include <SoapySDR/Device.hpp>
 #include <SoapySDR/Modules.hpp>
+#include <SoapySDR/Logger.hpp>
 #include <dsp/stream.h>
 #include <dsp/types.h>
+#include <spdlog/spdlog.h>

 namespace io {
    class SoapyWrapper {
    public:
        SoapyWrapper() {
+            SoapySDR::registerLogHandler(_logHandler);
            output.init(64000);
            currentGains = new float[1];
            refresh();
@@ -131,10 +134,21 @@ namespace io {
                } 
                _this->output.write(buf, res);
            }
-            printf("Read worker terminated\n");
            delete[] buf;
        }

+        static void _logHandler(const SoapySDRLogLevel lvl, const char* message) {
+            if (lvl == SOAPY_SDR_FATAL || lvl == SOAPY_SDR_CRITICAL || lvl == SOAPY_SDR_ERROR) {
+                spdlog::error(message);
+            }
+            else if (lvl == SOAPY_SDR_WARNING) {
+                spdlog::warn(message);
+            }
+            else if (lvl == SOAPY_SDR_NOTICE | SOAPY_SDR_INFO) {
+                spdlog::info(message);
+            }
+        }
+
        SoapySDR::Kwargs args;
        SoapySDR::Device* dev;
        SoapySDR::Stream* _stream;
--- a/src/json.hpp
+++ b/src/json.hpp
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -8,14 +8,15 @@
 #include <styles.h>
 #include <icons.h>
 #include <version.h>
-
+#include <spdlog/spdlog.h>
+#include <bandplan.h>

 #ifdef _WIN32
 #include <Windows.h>
 #endif

 static void glfw_error_callback(int error, const char* description) {
-    fprintf(stderr, "Glfw Error %d: %s\n", error, description);
+    spdlog::error("Glfw Error {0}: {1}", error, description);
 }

 int main() {
@@ -23,6 +24,8 @@ int main() {
    //FreeConsole();
 #endif

+    spdlog::info("SDR++ v" VERSION_STR);
+
    // Setup window
    glfwSetErrorCallback(glfw_error_callback);
    if (!glfwInit()) {
@@ -42,7 +45,7 @@ int main() {
    glfwSwapInterval(1); // Enable vsync

    if (glewInit() != GLEW_OK) {
-        fprintf(stderr, "Failed to initialize OpenGL loader!\n");
+        spdlog::error("Failed to initialize OpenGL loader!");
        return 1;
    }

@@ -60,9 +63,17 @@ int main() {

    windowInit();

-    printf("Loading icons...\n");
+    spdlog::info("Loading icons");
    icons::load();

+    spdlog::info("Loading band plans");
+    bandplan::loadFromDir("bandplans");
+
+    spdlog::info("Loading band plans color table");
+    bandplan::loadColorTable("band_colors.json");
+
+    spdlog::info("Ready.");
+
    // Main loop
    while (!glfwWindowShouldClose(window)) {
        glfwPollEvents();
--- a/src/main_window.cpp
+++ b/src/main_window.cpp
@@ -13,6 +13,8 @@
 #include <signal_path.h>
 #include <io/soapy.h>
 #include <icons.h>
+#include <bandplan.h>
+#include <watcher.h>

 std::thread worker;
 std::mutex fft_mtx;
@@ -64,50 +66,27 @@ void windowInit() {
    fft_out = (fftwf_complex*) fftwf_malloc(sizeof(fftwf_complex) * fftSize);
    p = fftwf_plan_dft_1d(fftSize, fft_in, fft_out, FFTW_FORWARD, FFTW_ESTIMATE);

-    printf("Starting DSP Thread!\n");
-
    sigPath.init(sampleRate, 20, fftSize, &soapy.output, (dsp::complex_t*)fft_in, fftHandler);
    sigPath.start();

    uiGains = new float[1];
 }

-int devId = 0;
-int _devId = -1;
-
-int srId = 0;
-int _srId = -1;
-
-bool showExample = false;
-
-long freq = 90500000;
-long _freq = 90500000;
-
+watcher<int> devId(0, true);
+watcher<int> srId(0, true);
+watcher<int> bandplanId(0, true);
+watcher<long> freq(90500000L);
 int demod = 1;
-
-bool state = false;
-bool mulstate = true;
-
-float vfoFreq = 92000000.0f;
-float lastVfoFreq = 92000000.0f;
-
-float volume = 1.0f;
-float lastVolume = 1.0f;
-
+watcher<float> vfoFreq(92000000.0f);
+watcher<float> volume(1.0f);
 float fftMin = -70.0f;
 float fftMax = 0.0f;
-
-float offset = 0.0f;
-float lastOffset = -1.0f;
-float bw = 8000000.0f;
-float lastBW = -1.0f;
-
+watcher<float> offset(0.0f, true);
+watcher<float> bw(8000000.0f, true);
 int sampleRate = 1000000;
-
 bool playing = false;
-
-bool dcbias = false;
-bool _dcbias = false;
+watcher<bool> dcbias(false, false);
+watcher<bool> bandPlanEnabled(true, false);

 void setVFO(float freq) {
    float currentOff =  wtf.getVFOOfset();
@@ -216,17 +195,14 @@ void drawWindow() {
        fSel.setFrequency(wtf.getCenterFrequency() + wtf.getVFOOfset());
    }

-    if (volume != lastVolume) {
-        lastVolume = volume;
-        sigPath.setVolume(volume);
+    if (volume.changed()) {
+        sigPath.setVolume(volume.val);
    }

-    if (devId != _devId && soapy.devList.size() > 0) {
-        _devId = devId;
-        soapy.setDevice(soapy.devList[devId]);
-        srId = 0;
-        _srId = -1;
-        soapy.setSampleRate(soapy.sampleRates[0]);
+    if (devId.changed() && soapy.devList.size() > 0) {
+        spdlog::info("Changed input device: {0}", devId.val);
+        soapy.setDevice(soapy.devList[devId.val]);
+        srId.markAsChanged();
        if (soapy.gainList.size() == 0) {
            return;
        }
@@ -237,20 +213,26 @@ void drawWindow() {
        }
    }

-    if (srId != _srId && soapy.devList.size() > 0) {
-        _srId = srId;
-        sampleRate = soapy.sampleRates[srId];
-        printf("Setting sample rate to %f\n", (float)soapy.sampleRates[srId]);
+    if (srId.changed() && soapy.devList.size() > 0) {
+        spdlog::info("Changed sample rate: {0}", srId.val);
+        sampleRate = soapy.sampleRates[srId.val];
        soapy.setSampleRate(sampleRate);
        wtf.setBandwidth(sampleRate);
        wtf.setViewBandwidth(sampleRate);
        sigPath.setSampleRate(sampleRate);
-        bw = sampleRate;
+        bw.val = sampleRate;
    }

-    if (dcbias != _dcbias) {
-        _dcbias = dcbias;
-        sigPath.setDCBiasCorrection(dcbias);
+    if (dcbias.changed()) {
+        sigPath.setDCBiasCorrection(dcbias.val);
+    }
+
+    if (bandplanId.changed() && bandPlanEnabled.val) {
+        wtf.bandplan = &bandplan::bandplans[bandplan::bandplanNames[bandplanId.val]];
+    }
+
+    if (bandPlanEnabled.changed()) {
+        wtf.bandplan = bandPlanEnabled.val ? &bandplan::bandplans[bandplan::bandplanNames[bandplanId.val]] : NULL;
    }

    ImVec2 vMin = ImGui::GetWindowContentRegionMin();
@@ -278,7 +260,7 @@ void drawWindow() {

    ImGui::SetCursorPosY(ImGui::GetCursorPosY() + 8);
    ImGui::SetNextItemWidth(200);
-    ImGui::SliderFloat("##_2_", &volume, 0.0f, 1.0f, "");
+    ImGui::SliderFloat("##_2_", &volume.val, 0.0f, 1.0f, "");

    ImGui::SameLine();

@@ -295,14 +277,14 @@ void drawWindow() {

    if (ImGui::CollapsingHeader("Source")) {
        ImGui::PushItemWidth(ImGui::GetWindowSize().x);
-        ImGui::Combo("##_0_", &devId, soapy.txtDevList.c_str());
-
+        ImGui::Combo("##_0_", &devId.val, soapy.txtDevList.c_str());
        ImGui::PopItemWidth();
+
        if (!playing) {
-            ImGui::Combo("##_1_", &srId, soapy.txtSampleRateList.c_str());
+            ImGui::Combo("##_1_", &srId.val, soapy.txtSampleRateList.c_str());
        }
        else {
-            ImGui::Text("%s Samples/s", soapy.txtSampleRateList.c_str());
+            ImGui::Text("%.0f Samples/s", soapy.sampleRates[srId.val]);
        }

        ImGui::SameLine();
@@ -316,11 +298,6 @@ void drawWindow() {
            sprintf(buf, "##_gain_slide_%d_", i);
            ImGui::SliderFloat(buf, &uiGains[i], soapy.gainRanges[i].minimum(), soapy.gainRanges[i].maximum());

-            // float step = soapy.gainRanges[i].step();
-            // printf("%f\n", step);
-
-            // uiGains[i] = roundf(uiGains[i] / soapy.gainRanges[i].step()) * soapy.gainRanges[i].step();
-
            if (uiGains[i] != soapy.currentGains[i]) {
                soapy.setGain(i, uiGains[i]);
            }
@@ -369,13 +346,23 @@ void drawWindow() {
        ImGui::Columns(1, "EndRadioModeColumns", false);

        //ImGui::InputInt("Frequency (kHz)", &freq);
-        ImGui::Checkbox("DC Bias Removal", &dcbias);
+        ImGui::Checkbox("DC Bias Removal", &dcbias.val);

        ImGui::EndGroup();
    }

    ImGui::CollapsingHeader("Audio");

+    if (ImGui::CollapsingHeader("Band Plan")) {
+        ImGui::PushItemWidth(ImGui::GetWindowSize().x);
+        ImGui::Combo("##_4_", &bandplanId.val, bandplan::bandplanNameTxt.c_str());
+        ImGui::PopItemWidth();
+        ImGui::Checkbox("Enabled", &bandPlanEnabled.val);
+        bandplan::BandPlan_t plan = bandplan::bandplans[bandplan::bandplanNames[bandplanId.val]];
+        ImGui::Text("Country: %s (%s)", plan.countryName, plan.countryCode);
+        ImGui::Text("Author: %s", plan.authorName);
+    } 
+
    ImGui::CollapsingHeader("Display");

    ImGui::CollapsingHeader("Recording");
@@ -397,7 +384,7 @@ void drawWindow() {
    ImGui::NextColumn();

    ImGui::Text("Zoom");
-    ImGui::VSliderFloat("##_7_", ImVec2(20.0f, 150.0f), &bw, sampleRate, 1000.0f, "");
+    ImGui::VSliderFloat("##_7_", ImVec2(20.0f, 150.0f), &bw.val, sampleRate, 1000.0f, "");

    ImGui::NewLine();

@@ -409,14 +396,11 @@ void drawWindow() {
    ImGui::Text("Min");
    ImGui::VSliderFloat("##_9_", ImVec2(20.0f, 150.0f), &fftMin, 0.0f, -100.0f, "");

-    if (bw != lastBW) {
-        lastBW = bw;
-        wtf.setViewBandwidth(bw);
+    if (bw.changed()) {
+        wtf.setViewBandwidth(bw.val);
        wtf.setViewOffset(wtf.getVFOOfset());
    }

-    
-
    wtf.setFFTMin(fftMin);
    wtf.setFFTMax(fftMax);
    wtf.setWaterfallMin(fftMin);
--- a/src/signal_path.cpp
+++ b/src/signal_path.cpp
@@ -9,10 +9,6 @@ void SignalPath::init(uint64_t sampleRate, int fftRate, int fftSize, dsp::stream
    this->fftRate = fftRate;
    this->fftSize = fftSize;

-    // for (int i = 0; i < iftaps.size(); i++) {
-    //     printf("%f\n", iftaps[i]);
-    // }
-
    _demod = DEMOD_FM;

    dcBiasRemover.init(input, 32000);
@@ -46,7 +42,8 @@ void SignalPath::setSampleRate(float sampleRate) {

    dcBiasRemover.setBlockSize(inputBlockSize);
    split.setBlockSize(inputBlockSize);
-    fftBlockDec.setSkip((sampleRate / fftRate) - fftSize);
+    int skip = (sampleRate / fftRate) - fftSize;
+    fftBlockDec.setSkip(skip);
    mainVFO.setInputSampleRate(sampleRate, inputBlockSize);

    // // Reset the modulator and audio systems
@@ -75,30 +72,24 @@ void SignalPath::setDemodulator(int demId) {

    // Stop current demodulator
    if (_demod == DEMOD_FM) {
-        printf("Stopping FM demodulator\n");
        demod.stop();
    }
    else if (_demod == DEMOD_NFM) {
-        printf("Stopping NFM demodulator\n");
        demod.stop();
    }
    else if (_demod == DEMOD_AM) {
-        printf("Stopping AM demodulator\n");
        amDemod.stop();
    }
    else if (_demod == DEMOD_USB) {
-        printf("Stopping USB demodulator\n");
        ssbDemod.stop();
    }
    else if (_demod == DEMOD_LSB) {
-        printf("Stopping LSB demodulator\n");
        ssbDemod.stop();
    }
    _demod = demId;

    // Set input of the audio resampler
    if (demId == DEMOD_FM) {
-        printf("Starting FM demodulator\n");
        mainVFO.setOutputSampleRate(200000, 200000);
        demod.setBlockSize(mainVFO.getOutputBlockSize());
        demod.setSampleRate(200000);
@@ -108,7 +99,6 @@ void SignalPath::setDemodulator(int demId) {
        demod.start();
    }
    if (demId == DEMOD_NFM) {
-        printf("Starting NFM demodulator\n");
        mainVFO.setOutputSampleRate(12500, 12500);
        demod.setBlockSize(mainVFO.getOutputBlockSize());
        demod.setSampleRate(12500);
@@ -118,7 +108,6 @@ void SignalPath::setDemodulator(int demId) {
        demod.start();
    }
    else if (demId == DEMOD_AM) {
-        printf("Starting AM demodulator\n");
        mainVFO.setOutputSampleRate(12500, 12500);
        amDemod.setBlockSize(mainVFO.getOutputBlockSize());
        audioResamp.setInput(&amDemod.output);
@@ -126,7 +115,6 @@ void SignalPath::setDemodulator(int demId) {
        amDemod.start();
    }
    else if (demId == DEMOD_USB) {
-        printf("Starting USB demodulator\n");
        mainVFO.setOutputSampleRate(6000, 3000);
        ssbDemod.setBlockSize(mainVFO.getOutputBlockSize());
        ssbDemod.setMode(dsp::SSBDemod::MODE_USB);
@@ -135,7 +123,6 @@ void SignalPath::setDemodulator(int demId) {
        ssbDemod.start();
    }
    else if (demId == DEMOD_LSB) {
-        printf("Starting LSB demodulator\n");
        mainVFO.setOutputSampleRate(6000, 3000);
        ssbDemod.setBlockSize(mainVFO.getOutputBlockSize());
        ssbDemod.setMode(dsp::SSBDemod::MODE_LSB);
@@ -156,8 +143,7 @@ void SignalPath::start() {

    mainVFO.start();
    demod.start();
-    //ns.start();
-    
+
    audioResamp.start();
    audio.start();
 }
--- a/src/spdlog/async.h
+++ b/src/spdlog/async.h
@@ -0,0 +1,93 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+//
+// Async logging using global thread pool
+// All loggers created here share same global thread pool.
+// Each log message is pushed to a queue along with a shared pointer to the
+// logger.
+// If a logger deleted while having pending messages in the queue, it's actual
+// destruction will defer
+// until all its messages are processed by the thread pool.
+// This is because each message in the queue holds a shared_ptr to the
+// originating logger.
+
+#include <spdlog/async_logger.h>
+#include <spdlog/details/registry.h>
+#include <spdlog/details/thread_pool.h>
+
+#include <memory>
+#include <mutex>
+#include <functional>
+
+namespace spdlog {
+
+namespace details {
+static const size_t default_async_q_size = 8192;
+}
+
+// async logger factory - creates async loggers backed with thread pool.
+// if a global thread pool doesn't already exist, create it with default queue
+// size of 8192 items and single thread.
+template<async_overflow_policy OverflowPolicy = async_overflow_policy::block>
+struct async_factory_impl
+{
+    template<typename Sink, typename... SinkArgs>
+    static std::shared_ptr<async_logger> create(std::string logger_name, SinkArgs &&... args)
+    {
+        auto &registry_inst = details::registry::instance();
+
+        // create global thread pool if not already exists..
+
+        auto &mutex = registry_inst.tp_mutex();
+        std::lock_guard<std::recursive_mutex> tp_lock(mutex);
+        auto tp = registry_inst.get_tp();
+        if (tp == nullptr)
+        {
+            tp = std::make_shared<details::thread_pool>(details::default_async_q_size, 1);
+            registry_inst.set_tp(tp);
+        }
+
+        auto sink = std::make_shared<Sink>(std::forward<SinkArgs>(args)...);
+        auto new_logger = std::make_shared<async_logger>(std::move(logger_name), std::move(sink), std::move(tp), OverflowPolicy);
+        registry_inst.initialize_logger(new_logger);
+        return new_logger;
+    }
+};
+
+using async_factory = async_factory_impl<async_overflow_policy::block>;
+using async_factory_nonblock = async_factory_impl<async_overflow_policy::overrun_oldest>;
+
+template<typename Sink, typename... SinkArgs>
+inline std::shared_ptr<spdlog::logger> create_async(std::string logger_name, SinkArgs &&... sink_args)
+{
+    return async_factory::create<Sink>(std::move(logger_name), std::forward<SinkArgs>(sink_args)...);
+}
+
+template<typename Sink, typename... SinkArgs>
+inline std::shared_ptr<spdlog::logger> create_async_nb(std::string logger_name, SinkArgs &&... sink_args)
+{
+    return async_factory_nonblock::create<Sink>(std::move(logger_name), std::forward<SinkArgs>(sink_args)...);
+}
+
+// set global thread pool.
+inline void init_thread_pool(size_t q_size, size_t thread_count, std::function<void()> on_thread_start)
+{
+    auto tp = std::make_shared<details::thread_pool>(q_size, thread_count, on_thread_start);
+    details::registry::instance().set_tp(std::move(tp));
+}
+
+// set global thread pool.
+inline void init_thread_pool(size_t q_size, size_t thread_count)
+{
+    init_thread_pool(q_size, thread_count, [] {});
+}
+
+// get the global thread pool.
+inline std::shared_ptr<spdlog::details::thread_pool> thread_pool()
+{
+    return details::registry::instance().get_tp();
+}
+} // namespace spdlog
--- a/src/spdlog/async_logger-inl.h
+++ b/src/spdlog/async_logger-inl.h
@@ -0,0 +1,92 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#ifndef SPDLOG_HEADER_ONLY
+#include <spdlog/async_logger.h>
+#endif
+
+#include <spdlog/sinks/sink.h>
+#include <spdlog/details/thread_pool.h>
+
+#include <memory>
+#include <string>
+
+SPDLOG_INLINE spdlog::async_logger::async_logger(
+    std::string logger_name, sinks_init_list sinks_list, std::weak_ptr<details::thread_pool> tp, async_overflow_policy overflow_policy)
+    : async_logger(std::move(logger_name), sinks_list.begin(), sinks_list.end(), std::move(tp), overflow_policy)
+{}
+
+SPDLOG_INLINE spdlog::async_logger::async_logger(
+    std::string logger_name, sink_ptr single_sink, std::weak_ptr<details::thread_pool> tp, async_overflow_policy overflow_policy)
+    : async_logger(std::move(logger_name), {std::move(single_sink)}, std::move(tp), overflow_policy)
+{}
+
+// send the log message to the thread pool
+SPDLOG_INLINE void spdlog::async_logger::sink_it_(const details::log_msg &msg)
+{
+    if (auto pool_ptr = thread_pool_.lock())
+    {
+        pool_ptr->post_log(shared_from_this(), msg, overflow_policy_);
+    }
+    else
+    {
+        throw_spdlog_ex("async log: thread pool doesn't exist anymore");
+    }
+}
+
+// send flush request to the thread pool
+SPDLOG_INLINE void spdlog::async_logger::flush_()
+{
+    if (auto pool_ptr = thread_pool_.lock())
+    {
+        pool_ptr->post_flush(shared_from_this(), overflow_policy_);
+    }
+    else
+    {
+        throw_spdlog_ex("async flush: thread pool doesn't exist anymore");
+    }
+}
+
+//
+// backend functions - called from the thread pool to do the actual job
+//
+SPDLOG_INLINE void spdlog::async_logger::backend_sink_it_(const details::log_msg &msg)
+{
+    for (auto &sink : sinks_)
+    {
+        if (sink->should_log(msg.level))
+        {
+            SPDLOG_TRY
+            {
+                sink->log(msg);
+            }
+            SPDLOG_LOGGER_CATCH()
+        }
+    }
+
+    if (should_flush_(msg))
+    {
+        backend_flush_();
+    }
+}
+
+SPDLOG_INLINE void spdlog::async_logger::backend_flush_()
+{
+    for (auto &sink : sinks_)
+    {
+        SPDLOG_TRY
+        {
+            sink->flush();
+        }
+        SPDLOG_LOGGER_CATCH()
+    }
+}
+
+SPDLOG_INLINE std::shared_ptr<spdlog::logger> spdlog::async_logger::clone(std::string new_name)
+{
+    auto cloned = std::make_shared<spdlog::async_logger>(*this);
+    cloned->name_ = std::move(new_name);
+    return cloned;
+}
--- a/src/spdlog/async_logger.h
+++ b/src/spdlog/async_logger.h
@@ -0,0 +1,68 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+// Fast asynchronous logger.
+// Uses pre allocated queue.
+// Creates a single back thread to pop messages from the queue and log them.
+//
+// Upon each log write the logger:
+//    1. Checks if its log level is enough to log the message
+//    2. Push a new copy of the message to a queue (or block the caller until
+//    space is available in the queue)
+// Upon destruction, logs all remaining messages in the queue before
+// destructing..
+
+#include <spdlog/logger.h>
+
+namespace spdlog {
+
+// Async overflow policy - block by default.
+enum class async_overflow_policy
+{
+    block,         // Block until message can be enqueued
+    overrun_oldest // Discard oldest message in the queue if full when trying to
+                   // add new item.
+};
+
+namespace details {
+class thread_pool;
+}
+
+class SPDLOG_API async_logger final : public std::enable_shared_from_this<async_logger>, public logger
+{
+    friend class details::thread_pool;
+
+public:
+    template<typename It>
+    async_logger(std::string logger_name, It begin, It end, std::weak_ptr<details::thread_pool> tp,
+        async_overflow_policy overflow_policy = async_overflow_policy::block)
+        : logger(std::move(logger_name), begin, end)
+        , thread_pool_(std::move(tp))
+        , overflow_policy_(overflow_policy)
+    {}
+
+    async_logger(std::string logger_name, sinks_init_list sinks_list, std::weak_ptr<details::thread_pool> tp,
+        async_overflow_policy overflow_policy = async_overflow_policy::block);
+
+    async_logger(std::string logger_name, sink_ptr single_sink, std::weak_ptr<details::thread_pool> tp,
+        async_overflow_policy overflow_policy = async_overflow_policy::block);
+
+    std::shared_ptr<logger> clone(std::string new_name) override;
+
+protected:
+    void sink_it_(const details::log_msg &msg) override;
+    void flush_() override;
+    void backend_sink_it_(const details::log_msg &incoming_log_msg);
+    void backend_flush_();
+
+private:
+    std::weak_ptr<details::thread_pool> thread_pool_;
+    async_overflow_policy overflow_policy_;
+};
+} // namespace spdlog
+
+#ifdef SPDLOG_HEADER_ONLY
+#include "async_logger-inl.h"
+#endif
--- a/src/spdlog/cfg/argv.h
+++ b/src/spdlog/cfg/argv.h
@@ -0,0 +1,45 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+#include <spdlog/cfg/helpers.h>
+#include <spdlog/details/registry.h>
+
+//
+// Init log levels using each argv entry that starts with "SPDLOG_LEVEL="
+//
+// set all loggers to debug level:
+// example.exe "SPDLOG_LEVEL=debug"
+
+// set logger1 to trace level
+// example.exe "SPDLOG_LEVEL=logger1=trace"
+
+// turn off all logging except for logger1 and logger2:
+// example.exe "SPDLOG_LEVEL=off,logger1=debug,logger2=info"
+
+namespace spdlog {
+namespace cfg {
+
+// search for SPDLOG_LEVEL= in the args and use it to init the levels
+void load_argv_levels(int argc, const char **argv)
+{
+    const std::string spdlog_level_prefix = "SPDLOG_LEVEL=";
+    for (int i = 1; i < argc; i++)
+    {
+        std::string arg = argv[i];
+        if (arg.find(spdlog_level_prefix) == 0)
+        {
+            auto levels_string = arg.substr(spdlog_level_prefix.size());
+            auto levels = helpers::extract_levels(levels_string);
+            details::registry::instance().update_levels(std::move(levels));
+        }
+    }
+}
+
+void load_argv_levels(int argc, char **argv)
+{
+    load_argv_levels(argc, const_cast<const char **>(argv));
+}
+
+} // namespace cfg
+} // namespace spdlog
--- a/src/spdlog/cfg/env.h
+++ b/src/spdlog/cfg/env.h
@@ -0,0 +1,36 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+#include <spdlog/cfg/helpers.h>
+#include <spdlog/details/registry.h>
+#include <spdlog/details/os.h>
+
+//
+// Init levels and patterns from env variables SPDLOG_LEVEL
+// Inspired from Rust's "env_logger" crate (https://crates.io/crates/env_logger).
+// Note - fallback to "info" level on unrecognized levels
+//
+// Examples:
+//
+// set global level to debug:
+// export SPDLOG_LEVEL=debug
+//
+// turn off all logging except for logger1:
+// export SPDLOG_LEVEL="off,logger1=debug"
+//
+
+// turn off all logging except for logger1 and logger2:
+// export SPDLOG_LEVEL="off,logger1=debug,logger2=info"
+
+namespace spdlog {
+namespace cfg {
+void load_env_levels()
+{
+    auto env_val = details::os::getenv("SPDLOG_LEVEL");
+    auto levels = helpers::extract_levels(env_val);
+    details::registry::instance().update_levels(std::move(levels));
+}
+
+} // namespace cfg
+} // namespace spdlog
--- a/src/spdlog/cfg/helpers-inl.h
+++ b/src/spdlog/cfg/helpers-inl.h
@@ -0,0 +1,103 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#ifndef SPDLOG_HEADER_ONLY
+#include <spdlog/cfg/helpers.h>
+#endif
+
+#include <spdlog/spdlog.h>
+#include <spdlog/details/os.h>
+#include <spdlog/details/registry.h>
+
+#include <string>
+#include <utility>
+#include <sstream>
+
+namespace spdlog {
+namespace cfg {
+namespace helpers {
+
+// inplace convert to lowercase
+inline std::string &to_lower_(std::string &str)
+{
+    std::transform(
+        str.begin(), str.end(), str.begin(), [](char ch) { return static_cast<char>((ch >= 'A' && ch <= 'Z') ? ch + ('a' - 'A') : ch); });
+    return str;
+}
+
+// inplace trim spaces
+inline std::string &trim_(std::string &str)
+{
+    const char *spaces = " \n\r\t";
+    str.erase(str.find_last_not_of(spaces) + 1);
+    str.erase(0, str.find_first_not_of(spaces));
+    return str;
+}
+
+// return (name,value) trimmed pair from given "name=value" string.
+// return empty string on missing parts
+// "key=val" => ("key", "val")
+// " key  =  val " => ("key", "val")
+// "key=" => ("key", "")
+// "val" => ("", "val")
+
+inline std::pair<std::string, std::string> extract_kv_(char sep, const std::string &str)
+{
+    auto n = str.find(sep);
+    std::string k, v;
+    if (n == std::string::npos)
+    {
+        v = str;
+    }
+    else
+    {
+        k = str.substr(0, n);
+        v = str.substr(n + 1);
+    }
+    return std::make_pair(trim_(k), trim_(v));
+}
+
+// return vector of key/value pairs from sequence of "K1=V1,K2=V2,.."
+// "a=AAA,b=BBB,c=CCC,.." => {("a","AAA"),("b","BBB"),("c", "CCC"),...}
+inline std::unordered_map<std::string, std::string> extract_key_vals_(const std::string &str)
+{
+    std::string token;
+    std::istringstream token_stream(str);
+    std::unordered_map<std::string, std::string> rv{};
+    while (std::getline(token_stream, token, ','))
+    {
+        if (token.empty())
+        {
+            continue;
+        }
+        auto kv = extract_kv_('=', token);
+        rv[kv.first] = kv.second;
+    }
+    return rv;
+}
+
+SPDLOG_INLINE log_levels extract_levels(const std::string &input)
+{
+    auto key_vals = extract_key_vals_(input);
+    log_levels rv;
+
+    for (auto &name_level : key_vals)
+    {
+        auto &logger_name = name_level.first;
+        auto level_name = to_lower_(name_level.second);
+        auto level = level::from_str(level_name);
+        // fallback to "info" if unrecognized level name
+        if (level == level::off && level_name != "off")
+        {
+            level = level::info;
+        }
+        rv.set(logger_name, level);
+    }
+    return rv;
+}
+
+} // namespace helpers
+} // namespace cfg
+} // namespace spdlog
--- a/src/spdlog/cfg/helpers.h
+++ b/src/spdlog/cfg/helpers.h
@@ -0,0 +1,28 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include <spdlog/cfg/log_levels.h>
+
+namespace spdlog {
+namespace cfg {
+namespace helpers {
+//
+// Init levels from given string
+//
+// Examples:
+//
+// set global level to debug: "debug"
+// turn off all logging except for logger1: "off,logger1=debug"
+// turn off all logging except for logger1 and logger2: "off,logger1=debug,logger2=info"
+//
+SPDLOG_API log_levels extract_levels(const std::string &txt);
+} // namespace helpers
+
+} // namespace cfg
+} // namespace spdlog
+
+#ifdef SPDLOG_HEADER_ONLY
+#include "helpers-inl.h"
+#endif // SPDLOG_HEADER_ONLY
--- a/src/spdlog/cfg/log_levels.h
+++ b/src/spdlog/cfg/log_levels.h
@@ -0,0 +1,47 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include <spdlog/common.h>
+#include <string>
+#include <unordered_map>
+
+namespace spdlog {
+namespace cfg {
+class log_levels
+{
+    std::unordered_map<std::string, spdlog::level::level_enum> levels_;
+    spdlog::level::level_enum default_level_ = level::info;
+
+public:
+    void set(const std::string &logger_name, level::level_enum lvl)
+    {
+        if (logger_name.empty())
+        {
+            default_level_ = lvl;
+        }
+        else
+        {
+            levels_[logger_name] = lvl;
+        }
+    }
+
+    void set_default(level::level_enum lvl)
+    {
+        default_level_ = lvl;
+    }
+
+    level::level_enum get(const std::string &logger_name)
+    {
+        auto it = levels_.find(logger_name);
+        return it != levels_.end() ? it->second : default_level_;
+    }
+
+    level::level_enum default_level()
+    {
+        return default_level_;
+    }
+};
+} // namespace cfg
+} // namespace spdlog
--- a/src/spdlog/common-inl.h
+++ b/src/spdlog/common-inl.h
@@ -0,0 +1,76 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#ifndef SPDLOG_HEADER_ONLY
+#include <spdlog/common.h>
+#endif
+
+namespace spdlog {
+namespace level {
+static string_view_t level_string_views[] SPDLOG_LEVEL_NAMES;
+
+static const char *short_level_names[] SPDLOG_SHORT_LEVEL_NAMES;
+
+SPDLOG_INLINE string_view_t &to_string_view(spdlog::level::level_enum l) SPDLOG_NOEXCEPT
+{
+    return level_string_views[l];
+}
+
+SPDLOG_INLINE const char *to_short_c_str(spdlog::level::level_enum l) SPDLOG_NOEXCEPT
+{
+    return short_level_names[l];
+}
+
+SPDLOG_INLINE spdlog::level::level_enum from_str(const std::string &name) SPDLOG_NOEXCEPT
+{
+    int level = 0;
+    for (const auto &level_str : level_string_views)
+    {
+        if (level_str == name)
+        {
+            return static_cast<level::level_enum>(level);
+        }
+        level++;
+    }
+    // check also for "warn" and "err" before giving up..
+    if (name == "warn")
+    {
+        return level::warn;
+    }
+    if (name == "err")
+    {
+        return level::err;
+    }
+    return level::off;
+}
+} // namespace level
+
+SPDLOG_INLINE spdlog_ex::spdlog_ex(std::string msg)
+    : msg_(std::move(msg))
+{}
+
+SPDLOG_INLINE spdlog_ex::spdlog_ex(const std::string &msg, int last_errno)
+{
+    memory_buf_t outbuf;
+    fmt::format_system_error(outbuf, last_errno, msg);
+    msg_ = fmt::to_string(outbuf);
+}
+
+SPDLOG_INLINE const char *spdlog_ex::what() const SPDLOG_NOEXCEPT
+{
+    return msg_.c_str();
+}
+
+SPDLOG_INLINE void throw_spdlog_ex(const std::string &msg, int last_errno)
+{
+    SPDLOG_THROW(spdlog_ex(msg, last_errno));
+}
+
+SPDLOG_INLINE void throw_spdlog_ex(std::string msg)
+{
+    SPDLOG_THROW(spdlog_ex(std::move(msg)));
+}
+
+} // namespace spdlog
--- a/src/spdlog/common.h
+++ b/src/spdlog/common.h
@@ -0,0 +1,246 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include <spdlog/tweakme.h>
+#include <spdlog/details/null_mutex.h>
+
+#include <atomic>
+#include <chrono>
+#include <initializer_list>
+#include <memory>
+#include <exception>
+#include <string>
+#include <type_traits>
+#include <functional>
+
+#ifdef SPDLOG_COMPILED_LIB
+#undef SPDLOG_HEADER_ONLY
+#if defined(_WIN32) && defined(SPDLOG_SHARED_LIB)
+#ifdef spdlog_EXPORTS
+#define SPDLOG_API __declspec(dllexport)
+#else
+#define SPDLOG_API __declspec(dllimport)
+#endif
+#else // !defined(_WIN32) || !defined(SPDLOG_SHARED_LIB)
+#define SPDLOG_API
+#endif
+#define SPDLOG_INLINE
+#else // !defined(SPDLOG_COMPILED_LIB)
+#define SPDLOG_API
+#define SPDLOG_HEADER_ONLY
+#define SPDLOG_INLINE inline
+#endif // #ifdef SPDLOG_COMPILED_LIB
+
+#include <spdlog/fmt/fmt.h>
+
+// visual studio upto 2013 does not support noexcept nor constexpr
+#if defined(_MSC_VER) && (_MSC_VER < 1900)
+#define SPDLOG_NOEXCEPT _NOEXCEPT
+#define SPDLOG_CONSTEXPR
+#else
+#define SPDLOG_NOEXCEPT noexcept
+#define SPDLOG_CONSTEXPR constexpr
+#endif
+
+#if defined(__GNUC__) || defined(__clang__)
+#define SPDLOG_DEPRECATED __attribute__((deprecated))
+#elif defined(_MSC_VER)
+#define SPDLOG_DEPRECATED __declspec(deprecated)
+#else
+#define SPDLOG_DEPRECATED
+#endif
+
+// disable thread local on msvc 2013
+#ifndef SPDLOG_NO_TLS
+#if (defined(_MSC_VER) && (_MSC_VER < 1900)) || defined(__cplusplus_winrt)
+#define SPDLOG_NO_TLS 1
+#endif
+#endif
+
+#ifndef SPDLOG_FUNCTION
+#define SPDLOG_FUNCTION static_cast<const char *>(__FUNCTION__)
+#endif
+
+#ifdef SPDLOG_NO_EXCEPTIONS
+#define SPDLOG_TRY
+#define SPDLOG_THROW(ex)                                                                                                                   \
+    do                                                                                                                                     \
+    {                                                                                                                                      \
+        printf("spdlog fatal error: %s\n", ex.what());                                                                                     \
+        std::abort();                                                                                                                      \
+    } while (0)
+#define SPDLOG_CATCH_ALL()
+#else
+#define SPDLOG_TRY try
+#define SPDLOG_THROW(ex) throw(ex)
+#define SPDLOG_CATCH_ALL() catch (...)
+#endif
+
+namespace spdlog {
+
+class formatter;
+
+namespace sinks {
+class sink;
+}
+
+#if defined(_WIN32) && defined(SPDLOG_WCHAR_FILENAMES)
+using filename_t = std::wstring;
+#define SPDLOG_FILENAME_T(s) L##s
+#else
+using filename_t = std::string;
+#define SPDLOG_FILENAME_T(s) s
+#endif
+
+using log_clock = std::chrono::system_clock;
+using sink_ptr = std::shared_ptr<sinks::sink>;
+using sinks_init_list = std::initializer_list<sink_ptr>;
+using err_handler = std::function<void(const std::string &err_msg)>;
+using string_view_t = fmt::basic_string_view<char>;
+using wstring_view_t = fmt::basic_string_view<wchar_t>;
+using memory_buf_t = fmt::basic_memory_buffer<char, 250>;
+
+#ifdef SPDLOG_WCHAR_TO_UTF8_SUPPORT
+#ifndef _WIN32
+#error SPDLOG_WCHAR_TO_UTF8_SUPPORT only supported on windows
+#else
+template<typename T>
+struct is_convertible_to_wstring_view : std::is_convertible<T, wstring_view_t>
+{};
+#endif // _WIN32
+#else
+template<typename>
+struct is_convertible_to_wstring_view : std::false_type
+{};
+#endif // SPDLOG_WCHAR_TO_UTF8_SUPPORT
+
+#if defined(SPDLOG_NO_ATOMIC_LEVELS)
+using level_t = details::null_atomic_int;
+#else
+using level_t = std::atomic<int>;
+#endif
+
+#define SPDLOG_LEVEL_TRACE 0
+#define SPDLOG_LEVEL_DEBUG 1
+#define SPDLOG_LEVEL_INFO 2
+#define SPDLOG_LEVEL_WARN 3
+#define SPDLOG_LEVEL_ERROR 4
+#define SPDLOG_LEVEL_CRITICAL 5
+#define SPDLOG_LEVEL_OFF 6
+
+#if !defined(SPDLOG_ACTIVE_LEVEL)
+#define SPDLOG_ACTIVE_LEVEL SPDLOG_LEVEL_INFO
+#endif
+
+// Log level enum
+namespace level {
+enum level_enum
+{
+    trace = SPDLOG_LEVEL_TRACE,
+    debug = SPDLOG_LEVEL_DEBUG,
+    info = SPDLOG_LEVEL_INFO,
+    warn = SPDLOG_LEVEL_WARN,
+    err = SPDLOG_LEVEL_ERROR,
+    critical = SPDLOG_LEVEL_CRITICAL,
+    off = SPDLOG_LEVEL_OFF,
+    n_levels
+};
+
+#if !defined(SPDLOG_LEVEL_NAMES)
+#define SPDLOG_LEVEL_NAMES                                                                                                                 \
+    {                                                                                                                                      \
+        "trace", "debug", "info", "warning", "error", "critical", "off"                                                                    \
+    }
+#endif
+
+#if !defined(SPDLOG_SHORT_LEVEL_NAMES)
+
+#define SPDLOG_SHORT_LEVEL_NAMES                                                                                                           \
+    {                                                                                                                                      \
+        "T", "D", "I", "W", "E", "C", "O"                                                                                                  \
+    }
+#endif
+
+SPDLOG_API string_view_t &to_string_view(spdlog::level::level_enum l) SPDLOG_NOEXCEPT;
+SPDLOG_API const char *to_short_c_str(spdlog::level::level_enum l) SPDLOG_NOEXCEPT;
+SPDLOG_API spdlog::level::level_enum from_str(const std::string &name) SPDLOG_NOEXCEPT;
+
+using level_hasher = std::hash<int>;
+} // namespace level
+
+//
+// Color mode used by sinks with color support.
+//
+enum class color_mode
+{
+    always,
+    automatic,
+    never
+};
+
+//
+// Pattern time - specific time getting to use for pattern_formatter.
+// local time by default
+//
+enum class pattern_time_type
+{
+    local, // log localtime
+    utc    // log utc
+};
+
+//
+// Log exception
+//
+class SPDLOG_API spdlog_ex : public std::exception
+{
+public:
+    explicit spdlog_ex(std::string msg);
+    spdlog_ex(const std::string &msg, int last_errno);
+    const char *what() const SPDLOG_NOEXCEPT override;
+
+private:
+    std::string msg_;
+};
+
+SPDLOG_API void throw_spdlog_ex(const std::string &msg, int last_errno);
+SPDLOG_API void throw_spdlog_ex(std::string msg);
+
+struct source_loc
+{
+    SPDLOG_CONSTEXPR source_loc() = default;
+    SPDLOG_CONSTEXPR source_loc(const char *filename_in, int line_in, const char *funcname_in)
+        : filename{filename_in}
+        , line{line_in}
+        , funcname{funcname_in}
+    {}
+
+    SPDLOG_CONSTEXPR bool empty() const SPDLOG_NOEXCEPT
+    {
+        return line == 0;
+    }
+    const char *filename{nullptr};
+    int line{0};
+    const char *funcname{nullptr};
+};
+
+namespace details {
+// make_unique support for pre c++14
+
+#if __cplusplus >= 201402L // C++14 and beyond
+using std::make_unique;
+#else
+template<typename T, typename... Args>
+std::unique_ptr<T> make_unique(Args &&... args)
+{
+    static_assert(!std::is_array<T>::value, "arrays not supported");
+    return std::unique_ptr<T>(new T(std::forward<Args>(args)...));
+}
+#endif
+} // namespace details
+} // namespace spdlog
+
+#ifdef SPDLOG_HEADER_ONLY
+#include "common-inl.h"
+#endif
--- a/src/spdlog/details/backtracer-inl.h
+++ b/src/spdlog/details/backtracer-inl.h
@@ -0,0 +1,69 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#ifndef SPDLOG_HEADER_ONLY
+#include <spdlog/details/backtracer.h>
+#endif
+namespace spdlog {
+namespace details {
+SPDLOG_INLINE backtracer::backtracer(const backtracer &other)
+{
+    std::lock_guard<std::mutex> lock(other.mutex_);
+    enabled_ = other.enabled();
+    messages_ = other.messages_;
+}
+
+SPDLOG_INLINE backtracer::backtracer(backtracer &&other) SPDLOG_NOEXCEPT
+{
+    std::lock_guard<std::mutex> lock(other.mutex_);
+    enabled_ = other.enabled();
+    messages_ = std::move(other.messages_);
+}
+
+SPDLOG_INLINE backtracer &backtracer::operator=(backtracer other)
+{
+    std::lock_guard<std::mutex> lock(mutex_);
+    enabled_ = other.enabled();
+    messages_ = std::move(other.messages_);
+    return *this;
+}
+
+SPDLOG_INLINE void backtracer::enable(size_t size)
+{
+    std::lock_guard<std::mutex> lock{mutex_};
+    enabled_.store(true, std::memory_order_relaxed);
+    messages_ = circular_q<log_msg_buffer>{size};
+}
+
+SPDLOG_INLINE void backtracer::disable()
+{
+    std::lock_guard<std::mutex> lock{mutex_};
+    enabled_.store(false, std::memory_order_relaxed);
+}
+
+SPDLOG_INLINE bool backtracer::enabled() const
+{
+    return enabled_.load(std::memory_order_relaxed);
+}
+
+SPDLOG_INLINE void backtracer::push_back(const log_msg &msg)
+{
+    std::lock_guard<std::mutex> lock{mutex_};
+    messages_.push_back(log_msg_buffer{msg});
+}
+
+// pop all items in the q and apply the given fun on each of them.
+SPDLOG_INLINE void backtracer::foreach_pop(std::function<void(const details::log_msg &)> fun)
+{
+    std::lock_guard<std::mutex> lock{mutex_};
+    while (!messages_.empty())
+    {
+        auto &front_msg = messages_.front();
+        fun(front_msg);
+        messages_.pop_front();
+    }
+}
+} // namespace details
+} // namespace spdlog
--- a/src/spdlog/details/backtracer.h
+++ b/src/spdlog/details/backtracer.h
@@ -0,0 +1,45 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include <spdlog/details/log_msg_buffer.h>
+#include <spdlog/details/circular_q.h>
+
+#include <atomic>
+#include <mutex>
+#include <functional>
+
+// Store log messages in circular buffer.
+// Useful for storing debug data in case of error/warning happens.
+
+namespace spdlog {
+namespace details {
+class SPDLOG_API backtracer
+{
+    mutable std::mutex mutex_;
+    std::atomic<bool> enabled_{false};
+    circular_q<log_msg_buffer> messages_;
+
+public:
+    backtracer() = default;
+    backtracer(const backtracer &other);
+
+    backtracer(backtracer &&other) SPDLOG_NOEXCEPT;
+    backtracer &operator=(backtracer other);
+
+    void enable(size_t size);
+    void disable();
+    bool enabled() const;
+    void push_back(const log_msg &msg);
+
+    // pop all items in the q and apply the given fun on each of them.
+    void foreach_pop(std::function<void(const details::log_msg &)> fun);
+};
+
+} // namespace details
+} // namespace spdlog
+
+#ifdef SPDLOG_HEADER_ONLY
+#include "backtracer-inl.h"
+#endif
--- a/src/spdlog/details/circular_q.h
+++ b/src/spdlog/details/circular_q.h
@@ -0,0 +1,141 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+// circular q view of std::vector.
+#pragma once
+
+#include <vector>
+#include <cassert>
+
+namespace spdlog {
+namespace details {
+template<typename T>
+class circular_q
+{
+    size_t max_items_ = 0;
+    typename std::vector<T>::size_type head_ = 0;
+    typename std::vector<T>::size_type tail_ = 0;
+    size_t overrun_counter_ = 0;
+    std::vector<T> v_;
+
+public:
+    using value_type = T;
+
+    // empty ctor - create a disabled queue with no elements allocated at all
+    circular_q() = default;
+
+    explicit circular_q(size_t max_items)
+        : max_items_(max_items + 1) // one item is reserved as marker for full q
+        , v_(max_items_)
+    {}
+
+    circular_q(const circular_q &) = default;
+    circular_q &operator=(const circular_q &) = default;
+
+    // move cannot be default,
+    // since we need to reset head_, tail_, etc to zero in the moved object
+    circular_q(circular_q &&other) SPDLOG_NOEXCEPT
+    {
+        copy_moveable(std::move(other));
+    }
+
+    circular_q &operator=(circular_q &&other) SPDLOG_NOEXCEPT
+    {
+        copy_moveable(std::move(other));
+        return *this;
+    }
+
+    // push back, overrun (oldest) item if no room left
+    void push_back(T &&item)
+    {
+        if (max_items_ > 0)
+        {
+            v_[tail_] = std::move(item);
+            tail_ = (tail_ + 1) % max_items_;
+
+            if (tail_ == head_) // overrun last item if full
+            {
+                head_ = (head_ + 1) % max_items_;
+                ++overrun_counter_;
+            }
+        }
+    }
+
+    // Return reference to the front item.
+    // If there are no elements in the container, the behavior is undefined.
+    const T &front() const
+    {
+        return v_[head_];
+    }
+
+    T &front()
+    {
+        return v_[head_];
+    }
+
+    // Return number of elements actually stored
+    size_t size() const
+    {
+        if (tail_ >= head_)
+        {
+            return tail_ - head_;
+        }
+        else
+        {
+            return max_items_ - (head_ - tail_);
+        }
+    }
+
+    // Return const reference to item by index.
+    // If index is out of range 0…size()-1, the behavior is undefined.
+    const T &at(size_t i) const
+    {
+        assert(i < size());
+        return v_[(head_ + i) % max_items_];
+    }
+
+    // Pop item from front.
+    // If there are no elements in the container, the behavior is undefined.
+    void pop_front()
+    {
+        head_ = (head_ + 1) % max_items_;
+    }
+
+    bool empty() const
+    {
+        return tail_ == head_;
+    }
+
+    bool full() const
+    {
+        // head is ahead of the tail by 1
+        if (max_items_ > 0)
+        {
+            return ((tail_ + 1) % max_items_) == head_;
+        }
+        return false;
+    }
+
+    size_t overrun_counter() const
+    {
+        return overrun_counter_;
+    }
+
+private:
+    // copy from other&& and reset it to disabled state
+    void copy_moveable(circular_q &&other) SPDLOG_NOEXCEPT
+    {
+        max_items_ = other.max_items_;
+        head_ = other.head_;
+        tail_ = other.tail_;
+        overrun_counter_ = other.overrun_counter_;
+        v_ = std::move(other.v_);
+
+        // put &&other in disabled, but valid state
+        other.max_items_ = 0;
+        other.head_ = other.tail_ = 0;
+        other.overrun_counter_ = 0;
+    }
+};
+} // namespace details
+} // namespace spdlog
--- a/src/spdlog/details/console_globals.h
+++ b/src/spdlog/details/console_globals.h
@@ -0,0 +1,32 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include <spdlog/details/null_mutex.h>
+#include <mutex>
+
+namespace spdlog {
+namespace details {
+
+struct console_mutex
+{
+    using mutex_t = std::mutex;
+    static mutex_t &mutex()
+    {
+        static mutex_t s_mutex;
+        return s_mutex;
+    }
+};
+
+struct console_nullmutex
+{
+    using mutex_t = null_mutex;
+    static mutex_t &mutex()
+    {
+        static mutex_t s_mutex;
+        return s_mutex;
+    }
+};
+} // namespace details
+} // namespace spdlog
--- a/src/spdlog/details/file_helper-inl.h
+++ b/src/spdlog/details/file_helper-inl.h
@@ -0,0 +1,132 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#ifndef SPDLOG_HEADER_ONLY
+#include <spdlog/details/file_helper.h>
+#endif
+
+#include <spdlog/details/os.h>
+#include <spdlog/common.h>
+
+#include <cerrno>
+#include <chrono>
+#include <cstdio>
+#include <string>
+#include <thread>
+#include <tuple>
+
+namespace spdlog {
+namespace details {
+
+SPDLOG_INLINE file_helper::~file_helper()
+{
+    close();
+}
+
+SPDLOG_INLINE void file_helper::open(const filename_t &fname, bool truncate)
+{
+    close();
+    filename_ = fname;
+    auto *mode = truncate ? SPDLOG_FILENAME_T("wb") : SPDLOG_FILENAME_T("ab");
+
+    for (int tries = 0; tries < open_tries_; ++tries)
+    {
+        // create containing folder if not exists already.
+        os::create_dir(os::dir_name(fname));
+        if (!os::fopen_s(&fd_, fname, mode))
+        {
+            return;
+        }
+
+        details::os::sleep_for_millis(open_interval_);
+    }
+
+    throw_spdlog_ex("Failed opening file " + os::filename_to_str(filename_) + " for writing", errno);
+}
+
+SPDLOG_INLINE void file_helper::reopen(bool truncate)
+{
+    if (filename_.empty())
+    {
+        throw_spdlog_ex("Failed re opening file - was not opened before");
+    }
+    this->open(filename_, truncate);
+}
+
+SPDLOG_INLINE void file_helper::flush()
+{
+    std::fflush(fd_);
+}
+
+SPDLOG_INLINE void file_helper::close()
+{
+    if (fd_ != nullptr)
+    {
+        std::fclose(fd_);
+        fd_ = nullptr;
+    }
+}
+
+SPDLOG_INLINE void file_helper::write(const memory_buf_t &buf)
+{
+    size_t msg_size = buf.size();
+    auto data = buf.data();
+    if (std::fwrite(data, 1, msg_size, fd_) != msg_size)
+    {
+        throw_spdlog_ex("Failed writing to file " + os::filename_to_str(filename_), errno);
+    }
+}
+
+SPDLOG_INLINE size_t file_helper::size() const
+{
+    if (fd_ == nullptr)
+    {
+        throw_spdlog_ex("Cannot use size() on closed file " + os::filename_to_str(filename_));
+    }
+    return os::filesize(fd_);
+}
+
+SPDLOG_INLINE const filename_t &file_helper::filename() const
+{
+    return filename_;
+}
+
+//
+// return file path and its extension:
+//
+// "mylog.txt" => ("mylog", ".txt")
+// "mylog" => ("mylog", "")
+// "mylog." => ("mylog.", "")
+// "/dir1/dir2/mylog.txt" => ("/dir1/dir2/mylog", ".txt")
+//
+// the starting dot in filenames is ignored (hidden files):
+//
+// ".mylog" => (".mylog". "")
+// "my_folder/.mylog" => ("my_folder/.mylog", "")
+// "my_folder/.mylog.txt" => ("my_folder/.mylog", ".txt")
+SPDLOG_INLINE std::tuple<filename_t, filename_t> file_helper::split_by_extension(const filename_t &fname)
+{
+    auto ext_index = fname.rfind('.');
+
+    // no valid extension found - return whole path and empty string as
+    // extension
+    if (ext_index == filename_t::npos || ext_index == 0 || ext_index == fname.size() - 1)
+    {
+        return std::make_tuple(fname, filename_t());
+    }
+
+    // treat cases like "/etc/rc.d/somelogfile or "/abc/.hiddenfile"
+    auto folder_index = fname.rfind(details::os::folder_sep);
+    if (folder_index != filename_t::npos && folder_index >= ext_index - 1)
+    {
+        return std::make_tuple(fname, filename_t());
+    }
+
+    // finally - return a valid base and extension tuple
+    return std::make_tuple(fname.substr(0, ext_index), fname.substr(ext_index));
+}
+
+} // namespace details
+} // namespace spdlog
--- a/src/spdlog/details/file_helper.h
+++ b/src/spdlog/details/file_helper.h
@@ -0,0 +1,59 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include <spdlog/common.h>
+#include <tuple>
+
+namespace spdlog {
+namespace details {
+
+// Helper class for file sinks.
+// When failing to open a file, retry several times(5) with a delay interval(10 ms).
+// Throw spdlog_ex exception on errors.
+
+class SPDLOG_API file_helper
+{
+public:
+    explicit file_helper() = default;
+
+    file_helper(const file_helper &) = delete;
+    file_helper &operator=(const file_helper &) = delete;
+    ~file_helper();
+
+    void open(const filename_t &fname, bool truncate = false);
+    void reopen(bool truncate);
+    void flush();
+    void close();
+    void write(const memory_buf_t &buf);
+    size_t size() const;
+    const filename_t &filename() const;
+
+    //
+    // return file path and its extension:
+    //
+    // "mylog.txt" => ("mylog", ".txt")
+    // "mylog" => ("mylog", "")
+    // "mylog." => ("mylog.", "")
+    // "/dir1/dir2/mylog.txt" => ("/dir1/dir2/mylog", ".txt")
+    //
+    // the starting dot in filenames is ignored (hidden files):
+    //
+    // ".mylog" => (".mylog". "")
+    // "my_folder/.mylog" => ("my_folder/.mylog", "")
+    // "my_folder/.mylog.txt" => ("my_folder/.mylog", ".txt")
+    static std::tuple<filename_t, filename_t> split_by_extension(const filename_t &fname);
+
+private:
+    const int open_tries_ = 5;
+    const int open_interval_ = 10;
+    std::FILE *fd_{nullptr};
+    filename_t filename_;
+};
+} // namespace details
+} // namespace spdlog
+
+#ifdef SPDLOG_HEADER_ONLY
+#include "file_helper-inl.h"
+#endif
--- a/src/spdlog/details/fmt_helper.h
+++ b/src/spdlog/details/fmt_helper.h
@@ -0,0 +1,116 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+#pragma once
+
+#include <chrono>
+#include <type_traits>
+#include <spdlog/fmt/fmt.h>
+#include <spdlog/common.h>
+
+// Some fmt helpers to efficiently format and pad ints and strings
+namespace spdlog {
+namespace details {
+namespace fmt_helper {
+
+inline spdlog::string_view_t to_string_view(const memory_buf_t &buf) SPDLOG_NOEXCEPT
+{
+    return spdlog::string_view_t{buf.data(), buf.size()};
+}
+
+inline void append_string_view(spdlog::string_view_t view, memory_buf_t &dest)
+{
+    auto *buf_ptr = view.data();
+    dest.append(buf_ptr, buf_ptr + view.size());
+}
+
+template<typename T>
+inline void append_int(T n, memory_buf_t &dest)
+{
+    fmt::format_int i(n);
+    dest.append(i.data(), i.data() + i.size());
+}
+
+template<typename T>
+inline unsigned int count_digits(T n)
+{
+    using count_type = typename std::conditional<(sizeof(T) > sizeof(uint32_t)), uint64_t, uint32_t>::type;
+    return static_cast<unsigned int>(fmt::
+// fmt 7.0.0 renamed the internal namespace to detail.
+// See: https://github.com/fmtlib/fmt/issues/1538
+#if FMT_VERSION < 70000
+internal
+#else
+detail
+#endif
+::count_digits(static_cast<count_type>(n)));
+}
+
+inline void pad2(int n, memory_buf_t &dest)
+{
+    if (n >= 0 && n < 100) // 0-99
+    {
+        dest.push_back(static_cast<char>('0' + n / 10));
+        dest.push_back(static_cast<char>('0' + n % 10));
+    }
+    else // unlikely, but just in case, let fmt deal with it
+    {
+        fmt::format_to(dest, "{:02}", n);
+    }
+}
+
+template<typename T>
+inline void pad_uint(T n, unsigned int width, memory_buf_t &dest)
+{
+    static_assert(std::is_unsigned<T>::value, "pad_uint must get unsigned T");
+    for (auto digits = count_digits(n); digits < width; digits++)
+    {
+        dest.push_back('0');
+    }
+    append_int(n, dest);
+}
+
+template<typename T>
+inline void pad3(T n, memory_buf_t &dest)
+{
+    static_assert(std::is_unsigned<T>::value, "pad3 must get unsigned T");
+    if (n < 1000)
+    {
+        dest.push_back(static_cast<char>(n / 100 + '0'));
+        n = n % 100;
+        dest.push_back(static_cast<char>((n / 10) + '0'));
+        dest.push_back(static_cast<char>((n % 10) + '0'));
+    }
+    else
+    {
+        append_int(n, dest);
+    }
+}
+
+template<typename T>
+inline void pad6(T n, memory_buf_t &dest)
+{
+    pad_uint(n, 6, dest);
+}
+
+template<typename T>
+inline void pad9(T n, memory_buf_t &dest)
+{
+    pad_uint(n, 9, dest);
+}
+
+// return fraction of a second of the given time_point.
+// e.g.
+// fraction<std::milliseconds>(tp) -> will return the millis part of the second
+template<typename ToDuration>
+inline ToDuration time_fraction(log_clock::time_point tp)
+{
+    using std::chrono::duration_cast;
+    using std::chrono::seconds;
+    auto duration = tp.time_since_epoch();
+    auto secs = duration_cast<seconds>(duration);
+    return duration_cast<ToDuration>(duration) - duration_cast<ToDuration>(secs);
+}
+
+} // namespace fmt_helper
+} // namespace details
+} // namespace spdlog
--- a/src/spdlog/details/log_msg-inl.h
+++ b/src/spdlog/details/log_msg-inl.h
@@ -0,0 +1,37 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#ifndef SPDLOG_HEADER_ONLY
+#include <spdlog/details/log_msg.h>
+#endif
+
+#include <spdlog/details/os.h>
+
+namespace spdlog {
+namespace details {
+
+SPDLOG_INLINE log_msg::log_msg(spdlog::log_clock::time_point log_time, spdlog::source_loc loc, string_view_t a_logger_name,
+    spdlog::level::level_enum lvl, spdlog::string_view_t msg)
+    : logger_name(a_logger_name)
+    , level(lvl)
+    , time(log_time)
+#ifndef SPDLOG_NO_THREAD_ID
+    , thread_id(os::thread_id())
+#endif
+    , source(loc)
+    , payload(msg)
+{}
+
+SPDLOG_INLINE log_msg::log_msg(
+    spdlog::source_loc loc, string_view_t a_logger_name, spdlog::level::level_enum lvl, spdlog::string_view_t msg)
+    : log_msg(os::now(), loc, a_logger_name, lvl, msg)
+{}
+
+SPDLOG_INLINE log_msg::log_msg(string_view_t a_logger_name, spdlog::level::level_enum lvl, spdlog::string_view_t msg)
+    : log_msg(os::now(), source_loc{}, a_logger_name, lvl, msg)
+{}
+
+} // namespace details
+} // namespace spdlog
--- a/src/spdlog/details/log_msg.h
+++ b/src/spdlog/details/log_msg.h
@@ -0,0 +1,36 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include <spdlog/common.h>
+#include <string>
+
+namespace spdlog {
+namespace details {
+struct SPDLOG_API log_msg
+{
+    log_msg() = default;
+    log_msg(log_clock::time_point log_time, source_loc loc, string_view_t logger_name, level::level_enum lvl, string_view_t msg);
+    log_msg(source_loc loc, string_view_t logger_name, level::level_enum lvl, string_view_t msg);
+    log_msg(string_view_t logger_name, level::level_enum lvl, string_view_t msg);
+    log_msg(const log_msg &other) = default;
+
+    string_view_t logger_name;
+    level::level_enum level{level::off};
+    log_clock::time_point time;
+    size_t thread_id{0};
+
+    // wrapping the formatted text with color (updated by pattern_formatter).
+    mutable size_t color_range_start{0};
+    mutable size_t color_range_end{0};
+
+    source_loc source;
+    string_view_t payload;
+};
+} // namespace details
+} // namespace spdlog
+
+#ifdef SPDLOG_HEADER_ONLY
+#include "log_msg-inl.h"
+#endif
--- a/src/spdlog/details/log_msg_buffer-inl.h
+++ b/src/spdlog/details/log_msg_buffer-inl.h
@@ -0,0 +1,58 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#ifndef SPDLOG_HEADER_ONLY
+#include <spdlog/details/log_msg_buffer.h>
+#endif
+
+namespace spdlog {
+namespace details {
+
+SPDLOG_INLINE log_msg_buffer::log_msg_buffer(const log_msg &orig_msg)
+    : log_msg{orig_msg}
+{
+    buffer.append(logger_name.begin(), logger_name.end());
+    buffer.append(payload.begin(), payload.end());
+    update_string_views();
+}
+
+SPDLOG_INLINE log_msg_buffer::log_msg_buffer(const log_msg_buffer &other)
+    : log_msg{other}
+{
+    buffer.append(logger_name.begin(), logger_name.end());
+    buffer.append(payload.begin(), payload.end());
+    update_string_views();
+}
+
+SPDLOG_INLINE log_msg_buffer::log_msg_buffer(log_msg_buffer &&other) SPDLOG_NOEXCEPT : log_msg{other}, buffer{std::move(other.buffer)}
+{
+    update_string_views();
+}
+
+SPDLOG_INLINE log_msg_buffer &log_msg_buffer::operator=(const log_msg_buffer &other)
+{
+    log_msg::operator=(other);
+    buffer.clear();
+    buffer.append(other.buffer.data(), other.buffer.data() + other.buffer.size());
+    update_string_views();
+    return *this;
+}
+
+SPDLOG_INLINE log_msg_buffer &log_msg_buffer::operator=(log_msg_buffer &&other) SPDLOG_NOEXCEPT
+{
+    log_msg::operator=(other);
+    buffer = std::move(other.buffer);
+    update_string_views();
+    return *this;
+}
+
+SPDLOG_INLINE void log_msg_buffer::update_string_views()
+{
+    logger_name = string_view_t{buffer.data(), logger_name.size()};
+    payload = string_view_t{buffer.data() + logger_name.size(), payload.size()};
+}
+
+} // namespace details
+} // namespace spdlog
--- a/src/spdlog/details/log_msg_buffer.h
+++ b/src/spdlog/details/log_msg_buffer.h
@@ -0,0 +1,33 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include <spdlog/details/log_msg.h>
+
+namespace spdlog {
+namespace details {
+
+// Extend log_msg with internal buffer to store its payload.
+// This is needed since log_msg holds string_views that points to stack data.
+
+class SPDLOG_API log_msg_buffer : public log_msg
+{
+    memory_buf_t buffer;
+    void update_string_views();
+
+public:
+    log_msg_buffer() = default;
+    explicit log_msg_buffer(const log_msg &orig_msg);
+    log_msg_buffer(const log_msg_buffer &other);
+    log_msg_buffer(log_msg_buffer &&other) SPDLOG_NOEXCEPT;
+    log_msg_buffer &operator=(const log_msg_buffer &other);
+    log_msg_buffer &operator=(log_msg_buffer &&other) SPDLOG_NOEXCEPT;
+};
+
+} // namespace details
+} // namespace spdlog
+
+#ifdef SPDLOG_HEADER_ONLY
+#include "log_msg_buffer-inl.h"
+#endif
--- a/src/spdlog/details/mpmc_blocking_q.h
+++ b/src/spdlog/details/mpmc_blocking_q.h
@@ -0,0 +1,120 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+// multi producer-multi consumer blocking queue.
+// enqueue(..) - will block until room found to put the new message.
+// enqueue_nowait(..) - will return immediately with false if no room left in
+// the queue.
+// dequeue_for(..) - will block until the queue is not empty or timeout have
+// passed.
+
+#include <spdlog/details/circular_q.h>
+
+#include <condition_variable>
+#include <mutex>
+
+namespace spdlog {
+namespace details {
+
+template<typename T>
+class mpmc_blocking_queue
+{
+public:
+    using item_type = T;
+    explicit mpmc_blocking_queue(size_t max_items)
+        : q_(max_items)
+    {}
+
+#ifndef __MINGW32__
+    // try to enqueue and block if no room left
+    void enqueue(T &&item)
+    {
+        {
+            std::unique_lock<std::mutex> lock(queue_mutex_);
+            pop_cv_.wait(lock, [this] { return !this->q_.full(); });
+            q_.push_back(std::move(item));
+        }
+        push_cv_.notify_one();
+    }
+
+    // enqueue immediately. overrun oldest message in the queue if no room left.
+    void enqueue_nowait(T &&item)
+    {
+        {
+            std::unique_lock<std::mutex> lock(queue_mutex_);
+            q_.push_back(std::move(item));
+        }
+        push_cv_.notify_one();
+    }
+
+    // try to dequeue item. if no item found. wait upto timeout and try again
+    // Return true, if succeeded dequeue item, false otherwise
+    bool dequeue_for(T &popped_item, std::chrono::milliseconds wait_duration)
+    {
+        {
+            std::unique_lock<std::mutex> lock(queue_mutex_);
+            if (!push_cv_.wait_for(lock, wait_duration, [this] { return !this->q_.empty(); }))
+            {
+                return false;
+            }
+            popped_item = std::move(q_.front());
+            q_.pop_front();
+        }
+        pop_cv_.notify_one();
+        return true;
+    }
+
+#else
+    // apparently mingw deadlocks if the mutex is released before cv.notify_one(),
+    // so release the mutex at the very end each function.
+
+    // try to enqueue and block if no room left
+    void enqueue(T &&item)
+    {
+        std::unique_lock<std::mutex> lock(queue_mutex_);
+        pop_cv_.wait(lock, [this] { return !this->q_.full(); });
+        q_.push_back(std::move(item));
+        push_cv_.notify_one();
+    }
+
+    // enqueue immediately. overrun oldest message in the queue if no room left.
+    void enqueue_nowait(T &&item)
+    {
+        std::unique_lock<std::mutex> lock(queue_mutex_);
+        q_.push_back(std::move(item));
+        push_cv_.notify_one();
+    }
+
+    // try to dequeue item. if no item found. wait upto timeout and try again
+    // Return true, if succeeded dequeue item, false otherwise
+    bool dequeue_for(T &popped_item, std::chrono::milliseconds wait_duration)
+    {
+        std::unique_lock<std::mutex> lock(queue_mutex_);
+        if (!push_cv_.wait_for(lock, wait_duration, [this] { return !this->q_.empty(); }))
+        {
+            return false;
+        }
+        popped_item = std::move(q_.front());
+        q_.pop_front();
+        pop_cv_.notify_one();
+        return true;
+    }
+
+#endif
+
+    size_t overrun_counter()
+    {
+        std::unique_lock<std::mutex> lock(queue_mutex_);
+        return q_.overrun_counter();
+    }
+
+private:
+    std::mutex queue_mutex_;
+    std::condition_variable push_cv_;
+    std::condition_variable pop_cv_;
+    spdlog::details::circular_q<T> q_;
+};
+} // namespace details
+} // namespace spdlog
--- a/src/spdlog/details/null_mutex.h
+++ b/src/spdlog/details/null_mutex.h
@@ -0,0 +1,49 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include <atomic>
+#include <utility>
+// null, no cost dummy "mutex" and dummy "atomic" int
+
+namespace spdlog {
+namespace details {
+struct null_mutex
+{
+    void lock() const {}
+    void unlock() const {}
+    bool try_lock() const
+    {
+        return true;
+    }
+};
+
+struct null_atomic_int
+{
+    int value;
+    null_atomic_int() = default;
+
+    explicit null_atomic_int(int new_value)
+        : value(new_value)
+    {}
+
+    int load(std::memory_order = std::memory_order_relaxed) const
+    {
+        return value;
+    }
+
+    void store(int new_value, std::memory_order = std::memory_order_relaxed)
+    {
+        value = new_value;
+    }
+
+    int exchange(int new_value, std::memory_order = std::memory_order_relaxed)
+    {
+        std::swap(new_value, value);
+        return new_value; // return value before the call
+    }
+};
+
+} // namespace details
+} // namespace spdlog
--- a/src/spdlog/details/os-inl.h
+++ b/src/spdlog/details/os-inl.h
@@ -0,0 +1,554 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#ifndef SPDLOG_HEADER_ONLY
+#include <spdlog/details/os.h>
+#endif
+
+#include <spdlog/common.h>
+
+#include <algorithm>
+#include <chrono>
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+#include <ctime>
+#include <string>
+#include <thread>
+#include <array>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#ifdef _WIN32
+
+#include <io.h>      // _get_osfhandle and _isatty support
+#include <process.h> //  _get_pid support
+#include <spdlog/details/windows_include.h>
+
+#ifdef __MINGW32__
+#include <share.h>
+#endif
+
+#if defined(SPDLOG_WCHAR_TO_UTF8_SUPPORT) || defined(SPDLOG_WCHAR_FILENAMES)
+#include <limits>
+#endif
+
+#include <direct.h> // for _mkdir/_wmkdir
+
+#else // unix
+
+#include <fcntl.h>
+#include <unistd.h>
+
+#ifdef __linux__
+#include <sys/syscall.h> //Use gettid() syscall under linux to get thread id
+
+#elif defined(_AIX)
+#include <pthread.h> // for pthread_getthreadid_np
+
+#elif defined(__DragonFly__) || defined(__FreeBSD__)
+#include <pthread_np.h> // for pthread_getthreadid_np
+
+#elif defined(__NetBSD__)
+#include <lwp.h> // for _lwp_self
+
+#elif defined(__sun)
+#include <thread.h> // for thr_self
+#endif
+
+#endif // unix
+
+#ifndef __has_feature      // Clang - feature checking macros.
+#define __has_feature(x) 0 // Compatibility with non-clang compilers.
+#endif
+
+namespace spdlog {
+namespace details {
+namespace os {
+
+SPDLOG_INLINE spdlog::log_clock::time_point now() SPDLOG_NOEXCEPT
+{
+
+#if defined __linux__ && defined SPDLOG_CLOCK_COARSE
+    timespec ts;
+    ::clock_gettime(CLOCK_REALTIME_COARSE, &ts);
+    return std::chrono::time_point<log_clock, typename log_clock::duration>(
+        std::chrono::duration_cast<typename log_clock::duration>(std::chrono::seconds(ts.tv_sec) + std::chrono::nanoseconds(ts.tv_nsec)));
+
+#else
+    return log_clock::now();
+#endif
+}
+SPDLOG_INLINE std::tm localtime(const std::time_t &time_tt) SPDLOG_NOEXCEPT
+{
+
+#ifdef _WIN32
+    std::tm tm;
+    ::localtime_s(&tm, &time_tt);
+#else
+    std::tm tm;
+    ::localtime_r(&time_tt, &tm);
+#endif
+    return tm;
+}
+
+SPDLOG_INLINE std::tm localtime() SPDLOG_NOEXCEPT
+{
+    std::time_t now_t = ::time(nullptr);
+    return localtime(now_t);
+}
+
+SPDLOG_INLINE std::tm gmtime(const std::time_t &time_tt) SPDLOG_NOEXCEPT
+{
+
+#ifdef _WIN32
+    std::tm tm;
+    ::gmtime_s(&tm, &time_tt);
+#else
+    std::tm tm;
+    ::gmtime_r(&time_tt, &tm);
+#endif
+    return tm;
+}
+
+SPDLOG_INLINE std::tm gmtime() SPDLOG_NOEXCEPT
+{
+    std::time_t now_t = ::time(nullptr);
+    return gmtime(now_t);
+}
+
+// fopen_s on non windows for writing
+SPDLOG_INLINE bool fopen_s(FILE **fp, const filename_t &filename, const filename_t &mode)
+{
+#ifdef _WIN32
+#ifdef SPDLOG_WCHAR_FILENAMES
+    *fp = ::_wfsopen((filename.c_str()), mode.c_str(), _SH_DENYNO);
+#else
+    *fp = ::_fsopen((filename.c_str()), mode.c_str(), _SH_DENYNO);
+#endif
+#if defined(SPDLOG_PREVENT_CHILD_FD)
+    if (*fp != nullptr)
+    {
+        auto file_handle = reinterpret_cast<HANDLE>(_get_osfhandle(::_fileno(*fp)));
+        if (!::SetHandleInformation(file_handle, HANDLE_FLAG_INHERIT, 0))
+        {
+            ::fclose(*fp);
+            *fp = nullptr;
+        }
+    }
+#endif
+#else // unix
+#if defined(SPDLOG_PREVENT_CHILD_FD)
+    const int mode_flag = mode == SPDLOG_FILENAME_T("ab") ? O_APPEND : O_TRUNC;
+    const int fd = ::open((filename.c_str()), O_CREAT | O_WRONLY | O_CLOEXEC | mode_flag, mode_t(0644));
+    if (fd == -1)
+    {
+        return false;
+    }
+    *fp = ::fdopen(fd, mode.c_str());
+    if (*fp == nullptr)
+    {
+        ::close(fd);
+    }
+#else
+    *fp = ::fopen((filename.c_str()), mode.c_str());
+#endif
+#endif
+
+    return *fp == nullptr;
+}
+
+SPDLOG_INLINE int remove(const filename_t &filename) SPDLOG_NOEXCEPT
+{
+#if defined(_WIN32) && defined(SPDLOG_WCHAR_FILENAMES)
+    return ::_wremove(filename.c_str());
+#else
+    return std::remove(filename.c_str());
+#endif
+}
+
+SPDLOG_INLINE int remove_if_exists(const filename_t &filename) SPDLOG_NOEXCEPT
+{
+    return path_exists(filename) ? remove(filename) : 0;
+}
+
+SPDLOG_INLINE int rename(const filename_t &filename1, const filename_t &filename2) SPDLOG_NOEXCEPT
+{
+#if defined(_WIN32) && defined(SPDLOG_WCHAR_FILENAMES)
+    return ::_wrename(filename1.c_str(), filename2.c_str());
+#else
+    return std::rename(filename1.c_str(), filename2.c_str());
+#endif
+}
+
+// Return true if path exists (file or directory)
+SPDLOG_INLINE bool path_exists(const filename_t &filename) SPDLOG_NOEXCEPT
+{
+#ifdef _WIN32
+#ifdef SPDLOG_WCHAR_FILENAMES
+    auto attribs = ::GetFileAttributesW(filename.c_str());
+#else
+    auto attribs = ::GetFileAttributesA(filename.c_str());
+#endif
+    return attribs != INVALID_FILE_ATTRIBUTES;
+#else // common linux/unix all have the stat system call
+    struct stat buffer;
+    return (::stat(filename.c_str(), &buffer) == 0);
+#endif
+}
+
+// Return file size according to open FILE* object
+SPDLOG_INLINE size_t filesize(FILE *f)
+{
+    if (f == nullptr)
+    {
+        throw_spdlog_ex("Failed getting file size. fd is null");
+    }
+#if defined(_WIN32) && !defined(__CYGWIN__)
+    int fd = ::_fileno(f);
+#if _WIN64 // 64 bits
+    __int64 ret = ::_filelengthi64(fd);
+    if (ret >= 0)
+    {
+        return static_cast<size_t>(ret);
+    }
+
+#else // windows 32 bits
+    long ret = ::_filelength(fd);
+    if (ret >= 0)
+    {
+        return static_cast<size_t>(ret);
+    }
+#endif
+
+#else // unix
+// OpenBSD doesn't compile with :: before the fileno(..)
+#if defined(__OpenBSD__)
+    int fd = fileno(f);
+#else
+    int fd = ::fileno(f);
+#endif
+// 64 bits(but not in osx or cygwin, where fstat64 is deprecated)
+#if (defined(__linux__) || defined(__sun) || defined(_AIX)) && (defined(__LP64__) || defined(_LP64))
+    struct stat64 st;
+    if (::fstat64(fd, &st) == 0)
+    {
+        return static_cast<size_t>(st.st_size);
+    }
+#else // other unix or linux 32 bits or cygwin
+    struct stat st;
+    if (::fstat(fd, &st) == 0)
+    {
+        return static_cast<size_t>(st.st_size);
+    }
+#endif
+#endif
+    throw_spdlog_ex("Failed getting file size from fd", errno);
+    return 0; // will not be reached.
+}
+
+// Return utc offset in minutes or throw spdlog_ex on failure
+SPDLOG_INLINE int utc_minutes_offset(const std::tm &tm)
+{
+
+#ifdef _WIN32
+#if _WIN32_WINNT < _WIN32_WINNT_WS08
+    TIME_ZONE_INFORMATION tzinfo;
+    auto rv = ::GetTimeZoneInformation(&tzinfo);
+#else
+    DYNAMIC_TIME_ZONE_INFORMATION tzinfo;
+    auto rv = ::GetDynamicTimeZoneInformation(&tzinfo);
+#endif
+    if (rv == TIME_ZONE_ID_INVALID)
+        throw_spdlog_ex("Failed getting timezone info. ", errno);
+
+    int offset = -tzinfo.Bias;
+    if (tm.tm_isdst)
+    {
+        offset -= tzinfo.DaylightBias;
+    }
+    else
+    {
+        offset -= tzinfo.StandardBias;
+    }
+    return offset;
+#else
+
+#if defined(sun) || defined(__sun) || defined(_AIX) || (!defined(_BSD_SOURCE) && !defined(_GNU_SOURCE))
+    // 'tm_gmtoff' field is BSD extension and it's missing on SunOS/Solaris
+    struct helper
+    {
+        static long int calculate_gmt_offset(const std::tm &localtm = details::os::localtime(), const std::tm &gmtm = details::os::gmtime())
+        {
+            int local_year = localtm.tm_year + (1900 - 1);
+            int gmt_year = gmtm.tm_year + (1900 - 1);
+
+            long int days = (
+                // difference in day of year
+                localtm.tm_yday -
+                gmtm.tm_yday
+
+                // + intervening leap days
+                + ((local_year >> 2) - (gmt_year >> 2)) - (local_year / 100 - gmt_year / 100) +
+                ((local_year / 100 >> 2) - (gmt_year / 100 >> 2))
+
+                // + difference in years * 365 */
+                + (long int)(local_year - gmt_year) * 365);
+
+            long int hours = (24 * days) + (localtm.tm_hour - gmtm.tm_hour);
+            long int mins = (60 * hours) + (localtm.tm_min - gmtm.tm_min);
+            long int secs = (60 * mins) + (localtm.tm_sec - gmtm.tm_sec);
+
+            return secs;
+        }
+    };
+
+    auto offset_seconds = helper::calculate_gmt_offset(tm);
+#else
+    auto offset_seconds = tm.tm_gmtoff;
+#endif
+
+    return static_cast<int>(offset_seconds / 60);
+#endif
+}
+
+// Return current thread id as size_t
+// It exists because the std::this_thread::get_id() is much slower(especially
+// under VS 2013)
+SPDLOG_INLINE size_t _thread_id() SPDLOG_NOEXCEPT
+{
+#ifdef _WIN32
+    return static_cast<size_t>(::GetCurrentThreadId());
+#elif defined(__linux__)
+#if defined(__ANDROID__) && defined(__ANDROID_API__) && (__ANDROID_API__ < 21)
+#define SYS_gettid __NR_gettid
+#endif
+    return static_cast<size_t>(::syscall(SYS_gettid));
+#elif defined(_AIX) || defined(__DragonFly__) || defined(__FreeBSD__)
+    return static_cast<size_t>(::pthread_getthreadid_np());
+#elif defined(__NetBSD__)
+    return static_cast<size_t>(::_lwp_self());
+#elif defined(__OpenBSD__)
+    return static_cast<size_t>(::getthrid());
+#elif defined(__sun)
+    return static_cast<size_t>(::thr_self());
+#elif __APPLE__
+    uint64_t tid;
+    pthread_threadid_np(nullptr, &tid);
+    return static_cast<size_t>(tid);
+#else // Default to standard C++11 (other Unix)
+    return static_cast<size_t>(std::hash<std::thread::id>()(std::this_thread::get_id()));
+#endif
+}
+
+// Return current thread id as size_t (from thread local storage)
+SPDLOG_INLINE size_t thread_id() SPDLOG_NOEXCEPT
+{
+#if defined(SPDLOG_NO_TLS)
+    return _thread_id();
+#else // cache thread id in tls
+    static thread_local const size_t tid = _thread_id();
+    return tid;
+#endif
+}
+
+// This is avoid msvc issue in sleep_for that happens if the clock changes.
+// See https://github.com/gabime/spdlog/issues/609
+SPDLOG_INLINE void sleep_for_millis(int milliseconds) SPDLOG_NOEXCEPT
+{
+#if defined(_WIN32)
+    ::Sleep(milliseconds);
+#else
+    std::this_thread::sleep_for(std::chrono::milliseconds(milliseconds));
+#endif
+}
+
+// wchar support for windows file names (SPDLOG_WCHAR_FILENAMES must be defined)
+#if defined(_WIN32) && defined(SPDLOG_WCHAR_FILENAMES)
+SPDLOG_INLINE std::string filename_to_str(const filename_t &filename)
+{
+    memory_buf_t buf;
+    wstr_to_utf8buf(filename, buf);
+    return fmt::to_string(buf);
+}
+#else
+SPDLOG_INLINE std::string filename_to_str(const filename_t &filename)
+{
+    return filename;
+}
+#endif
+
+SPDLOG_INLINE int pid() SPDLOG_NOEXCEPT
+{
+
+#ifdef _WIN32
+    return static_cast<int>(::GetCurrentProcessId());
+#else
+    return static_cast<int>(::getpid());
+#endif
+}
+
+// Determine if the terminal supports colors
+// Based on: https://github.com/agauniyal/rang/
+SPDLOG_INLINE bool is_color_terminal() SPDLOG_NOEXCEPT
+{
+#ifdef _WIN32
+    return true;
+#else
+    static constexpr std::array<const char *, 14> terms = {
+        {"ansi", "color", "console", "cygwin", "gnome", "konsole", "kterm", "linux", "msys", "putty", "rxvt", "screen", "vt100", "xterm"}};
+
+    const char *env_p = std::getenv("TERM");
+    if (env_p == nullptr)
+    {
+        return false;
+    }
+
+    static const bool result =
+        std::any_of(terms.begin(), terms.end(), [&](const char *term) { return std::strstr(env_p, term) != nullptr; });
+    return result;
+#endif
+}
+
+// Determine if the terminal attached
+// Source: https://github.com/agauniyal/rang/
+SPDLOG_INLINE bool in_terminal(FILE *file) SPDLOG_NOEXCEPT
+{
+
+#ifdef _WIN32
+    return ::_isatty(_fileno(file)) != 0;
+#else
+    return ::isatty(fileno(file)) != 0;
+#endif
+}
+
+#if (defined(SPDLOG_WCHAR_TO_UTF8_SUPPORT) || defined(SPDLOG_WCHAR_FILENAMES)) && defined(_WIN32)
+SPDLOG_INLINE void wstr_to_utf8buf(wstring_view_t wstr, memory_buf_t &target)
+{
+    if (wstr.size() > static_cast<size_t>((std::numeric_limits<int>::max)()))
+    {
+        throw_spdlog_ex("UTF-16 string is too big to be converted to UTF-8");
+    }
+
+    int wstr_size = static_cast<int>(wstr.size());
+    if (wstr_size == 0)
+    {
+        target.resize(0);
+        return;
+    }
+
+    int result_size = static_cast<int>(target.capacity());
+    if ((wstr_size + 1) * 2 > result_size)
+    {
+        result_size = ::WideCharToMultiByte(CP_UTF8, 0, wstr.data(), wstr_size, NULL, 0, NULL, NULL);
+    }
+
+    if (result_size > 0)
+    {
+        target.resize(result_size);
+        result_size = ::WideCharToMultiByte(CP_UTF8, 0, wstr.data(), wstr_size, target.data(), result_size, NULL, NULL);
+
+        if (result_size > 0)
+        {
+            target.resize(result_size);
+            return;
+        }
+    }
+
+    throw_spdlog_ex(fmt::format("WideCharToMultiByte failed. Last error: {}", ::GetLastError()));
+}
+#endif // (defined(SPDLOG_WCHAR_TO_UTF8_SUPPORT) || defined(SPDLOG_WCHAR_FILENAMES)) && defined(_WIN32)
+
+// return true on success
+static SPDLOG_INLINE bool mkdir_(const filename_t &path)
+{
+#ifdef _WIN32
+#ifdef SPDLOG_WCHAR_FILENAMES
+    return ::_wmkdir(path.c_str()) == 0;
+#else
+    return ::_mkdir(path.c_str()) == 0;
+#endif
+#else
+    return ::mkdir(path.c_str(), mode_t(0755)) == 0;
+#endif
+}
+
+// create the given directory - and all directories leading to it
+// return true on success or if the directory already exists
+SPDLOG_INLINE bool create_dir(filename_t path)
+{
+    if (path_exists(path))
+    {
+        return true;
+    }
+
+    if (path.empty())
+    {
+        return false;
+    }
+
+#ifdef _WIN32
+    // support forward slash in windows
+    std::replace(path.begin(), path.end(), '/', folder_sep);
+#endif
+
+    size_t search_offset = 0;
+    do
+    {
+        auto token_pos = path.find(folder_sep, search_offset);
+        // treat the entire path as a folder if no folder separator not found
+        if (token_pos == filename_t::npos)
+        {
+            token_pos = path.size();
+        }
+
+        auto subdir = path.substr(0, token_pos);
+
+        if (!subdir.empty() && !path_exists(subdir) && !mkdir_(subdir))
+        {
+            return false; // return error if failed creating dir
+        }
+        search_offset = token_pos + 1;
+    } while (search_offset < path.size());
+
+    return true;
+}
+
+// Return directory name from given path or empty string
+// "abc/file" => "abc"
+// "abc/" => "abc"
+// "abc" => ""
+// "abc///" => "abc//"
+SPDLOG_INLINE filename_t dir_name(filename_t path)
+{
+#ifdef _WIN32
+    // support forward slash in windows
+    std::replace(path.begin(), path.end(), '/', folder_sep);
+#endif
+    auto pos = path.find_last_of(folder_sep);
+    return pos != filename_t::npos ? path.substr(0, pos) : filename_t{};
+}
+
+std::string SPDLOG_INLINE getenv(const char *field)
+{
+
+#if defined(_MSC_VER)
+#if defined(__cplusplus_winrt)
+    return std::string{}; // not supported under uwp
+#else
+    size_t len = 0;
+    char buf[128];
+    bool ok = ::getenv_s(&len, buf, sizeof(buf), field) == 0;
+    return ok ? buf : std::string{};
+#endif
+#else // revert to getenv
+    char *buf = ::getenv(field);
+    return buf ? buf : std::string{};
+#endif
+}
+
+} // namespace os
+} // namespace details
+} // namespace spdlog
--- a/src/spdlog/details/os.h
+++ b/src/spdlog/details/os.h
@@ -0,0 +1,111 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include <spdlog/common.h>
+#include <ctime> // std::time_t
+
+namespace spdlog {
+namespace details {
+namespace os {
+
+SPDLOG_API spdlog::log_clock::time_point now() SPDLOG_NOEXCEPT;
+
+SPDLOG_API std::tm localtime(const std::time_t &time_tt) SPDLOG_NOEXCEPT;
+
+SPDLOG_API std::tm localtime() SPDLOG_NOEXCEPT;
+
+SPDLOG_API std::tm gmtime(const std::time_t &time_tt) SPDLOG_NOEXCEPT;
+
+SPDLOG_API std::tm gmtime() SPDLOG_NOEXCEPT;
+
+// eol definition
+#if !defined(SPDLOG_EOL)
+#ifdef _WIN32
+#define SPDLOG_EOL "\r\n"
+#else
+#define SPDLOG_EOL "\n"
+#endif
+#endif
+
+SPDLOG_CONSTEXPR static const char *default_eol = SPDLOG_EOL;
+
+// folder separator
+#ifdef _WIN32
+static const char folder_sep = '\\';
+#else
+SPDLOG_CONSTEXPR static const char folder_sep = '/';
+#endif
+
+// fopen_s on non windows for writing
+SPDLOG_API bool fopen_s(FILE **fp, const filename_t &filename, const filename_t &mode);
+
+// Remove filename. return 0 on success
+SPDLOG_API int remove(const filename_t &filename) SPDLOG_NOEXCEPT;
+
+// Remove file if exists. return 0 on success
+// Note: Non atomic (might return failure to delete if concurrently deleted by other process/thread)
+SPDLOG_API int remove_if_exists(const filename_t &filename) SPDLOG_NOEXCEPT;
+
+SPDLOG_API int rename(const filename_t &filename1, const filename_t &filename2) SPDLOG_NOEXCEPT;
+
+// Return if file exists.
+SPDLOG_API bool path_exists(const filename_t &filename) SPDLOG_NOEXCEPT;
+
+// Return file size according to open FILE* object
+SPDLOG_API size_t filesize(FILE *f);
+
+// Return utc offset in minutes or throw spdlog_ex on failure
+SPDLOG_API int utc_minutes_offset(const std::tm &tm = details::os::localtime());
+
+// Return current thread id as size_t
+// It exists because the std::this_thread::get_id() is much slower(especially
+// under VS 2013)
+SPDLOG_API size_t _thread_id() SPDLOG_NOEXCEPT;
+
+// Return current thread id as size_t (from thread local storage)
+SPDLOG_API size_t thread_id() SPDLOG_NOEXCEPT;
+
+// This is avoid msvc issue in sleep_for that happens if the clock changes.
+// See https://github.com/gabime/spdlog/issues/609
+SPDLOG_API void sleep_for_millis(int milliseconds) SPDLOG_NOEXCEPT;
+
+SPDLOG_API std::string filename_to_str(const filename_t &filename);
+
+SPDLOG_API int pid() SPDLOG_NOEXCEPT;
+
+// Determine if the terminal supports colors
+// Source: https://github.com/agauniyal/rang/
+SPDLOG_API bool is_color_terminal() SPDLOG_NOEXCEPT;
+
+// Determine if the terminal attached
+// Source: https://github.com/agauniyal/rang/
+SPDLOG_API bool in_terminal(FILE *file) SPDLOG_NOEXCEPT;
+
+#if (defined(SPDLOG_WCHAR_TO_UTF8_SUPPORT) || defined(SPDLOG_WCHAR_FILENAMES)) && defined(_WIN32)
+SPDLOG_API void wstr_to_utf8buf(wstring_view_t wstr, memory_buf_t &target);
+#endif
+
+// Return directory name from given path or empty string
+// "abc/file" => "abc"
+// "abc/" => "abc"
+// "abc" => ""
+// "abc///" => "abc//"
+SPDLOG_API filename_t dir_name(filename_t path);
+
+// Create a dir from the given path.
+// Return true if succeeded or if this dir already exists.
+SPDLOG_API bool create_dir(filename_t path);
+
+// non thread safe, cross platform getenv/getenv_s
+// return empty string if field not found
+SPDLOG_API std::string getenv(const char *field);
+
+} // namespace os
+} // namespace details
+} // namespace spdlog
+
+#ifdef SPDLOG_HEADER_ONLY
+#include "os-inl.h"
+#endif
--- a/src/spdlog/details/periodic_worker-inl.h
+++ b/src/spdlog/details/periodic_worker-inl.h
@@ -0,0 +1,49 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#ifndef SPDLOG_HEADER_ONLY
+#include <spdlog/details/periodic_worker.h>
+#endif
+
+namespace spdlog {
+namespace details {
+
+SPDLOG_INLINE periodic_worker::periodic_worker(const std::function<void()> &callback_fun, std::chrono::seconds interval)
+{
+    active_ = (interval > std::chrono::seconds::zero());
+    if (!active_)
+    {
+        return;
+    }
+
+    worker_thread_ = std::thread([this, callback_fun, interval]() {
+        for (;;)
+        {
+            std::unique_lock<std::mutex> lock(this->mutex_);
+            if (this->cv_.wait_for(lock, interval, [this] { return !this->active_; }))
+            {
+                return; // active_ == false, so exit this thread
+            }
+            callback_fun();
+        }
+    });
+}
+
+// stop the worker thread and join it
+SPDLOG_INLINE periodic_worker::~periodic_worker()
+{
+    if (worker_thread_.joinable())
+    {
+        {
+            std::lock_guard<std::mutex> lock(mutex_);
+            active_ = false;
+        }
+        cv_.notify_one();
+        worker_thread_.join();
+    }
+}
+
+} // namespace details
+} // namespace spdlog
--- a/src/spdlog/details/periodic_worker.h
+++ b/src/spdlog/details/periodic_worker.h
@@ -0,0 +1,40 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+// periodic worker thread - periodically executes the given callback function.
+//
+// RAII over the owned thread:
+//    creates the thread on construction.
+//    stops and joins the thread on destruction (if the thread is executing a callback, wait for it to finish first).
+
+#include <chrono>
+#include <condition_variable>
+#include <functional>
+#include <mutex>
+#include <thread>
+namespace spdlog {
+namespace details {
+
+class SPDLOG_API periodic_worker
+{
+public:
+    periodic_worker(const std::function<void()> &callback_fun, std::chrono::seconds interval);
+    periodic_worker(const periodic_worker &) = delete;
+    periodic_worker &operator=(const periodic_worker &) = delete;
+    // stop the worker thread and join it
+    ~periodic_worker();
+
+private:
+    bool active_;
+    std::thread worker_thread_;
+    std::mutex mutex_;
+    std::condition_variable cv_;
+};
+} // namespace details
+} // namespace spdlog
+
+#ifdef SPDLOG_HEADER_ONLY
+#include "periodic_worker-inl.h"
+#endif
--- a/src/spdlog/details/registry-inl.h
+++ b/src/spdlog/details/registry-inl.h
@@ -0,0 +1,299 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#ifndef SPDLOG_HEADER_ONLY
+#include <spdlog/details/registry.h>
+#endif
+
+#include <spdlog/common.h>
+#include <spdlog/details/periodic_worker.h>
+#include <spdlog/logger.h>
+#include <spdlog/pattern_formatter.h>
+
+#ifndef SPDLOG_DISABLE_DEFAULT_LOGGER
+// support for the default stdout color logger
+#ifdef _WIN32
+#include <spdlog/sinks/wincolor_sink.h>
+#else
+#include <spdlog/sinks/ansicolor_sink.h>
+#endif
+#endif // SPDLOG_DISABLE_DEFAULT_LOGGER
+
+#include <chrono>
+#include <functional>
+#include <memory>
+#include <string>
+#include <unordered_map>
+
+namespace spdlog {
+namespace details {
+
+SPDLOG_INLINE registry::registry()
+    : formatter_(new pattern_formatter())
+{
+
+#ifndef SPDLOG_DISABLE_DEFAULT_LOGGER
+    // create default logger (ansicolor_stdout_sink_mt or wincolor_stdout_sink_mt in windows).
+#ifdef _WIN32
+    auto color_sink = std::make_shared<sinks::wincolor_stdout_sink_mt>();
+#else
+    auto color_sink = std::make_shared<sinks::ansicolor_stdout_sink_mt>();
+#endif
+
+    const char *default_logger_name = "";
+    default_logger_ = std::make_shared<spdlog::logger>(default_logger_name, std::move(color_sink));
+    loggers_[default_logger_name] = default_logger_;
+
+#endif // SPDLOG_DISABLE_DEFAULT_LOGGER
+}
+
+SPDLOG_INLINE registry::~registry() = default;
+
+SPDLOG_INLINE void registry::register_logger(std::shared_ptr<logger> new_logger)
+{
+    std::lock_guard<std::mutex> lock(logger_map_mutex_);
+    register_logger_(std::move(new_logger));
+}
+
+SPDLOG_INLINE void registry::initialize_logger(std::shared_ptr<logger> new_logger)
+{
+    std::lock_guard<std::mutex> lock(logger_map_mutex_);
+    new_logger->set_formatter(formatter_->clone());
+
+    if (err_handler_)
+    {
+        new_logger->set_error_handler(err_handler_);
+    }
+
+    new_logger->set_level(levels_.get(new_logger->name()));
+    new_logger->flush_on(flush_level_);
+
+    if (backtrace_n_messages_ > 0)
+    {
+        new_logger->enable_backtrace(backtrace_n_messages_);
+    }
+
+    if (automatic_registration_)
+    {
+        register_logger_(std::move(new_logger));
+    }
+}
+
+SPDLOG_INLINE std::shared_ptr<logger> registry::get(const std::string &logger_name)
+{
+    std::lock_guard<std::mutex> lock(logger_map_mutex_);
+    auto found = loggers_.find(logger_name);
+    return found == loggers_.end() ? nullptr : found->second;
+}
+
+SPDLOG_INLINE std::shared_ptr<logger> registry::default_logger()
+{
+    std::lock_guard<std::mutex> lock(logger_map_mutex_);
+    return default_logger_;
+}
+
+// Return raw ptr to the default logger.
+// To be used directly by the spdlog default api (e.g. spdlog::info)
+// This make the default API faster, but cannot be used concurrently with set_default_logger().
+// e.g do not call set_default_logger() from one thread while calling spdlog::info() from another.
+SPDLOG_INLINE logger *registry::get_default_raw()
+{
+    return default_logger_.get();
+}
+
+// set default logger.
+// default logger is stored in default_logger_ (for faster retrieval) and in the loggers_ map.
+SPDLOG_INLINE void registry::set_default_logger(std::shared_ptr<logger> new_default_logger)
+{
+    std::lock_guard<std::mutex> lock(logger_map_mutex_);
+    // remove previous default logger from the map
+    if (default_logger_ != nullptr)
+    {
+        loggers_.erase(default_logger_->name());
+    }
+    if (new_default_logger != nullptr)
+    {
+        loggers_[new_default_logger->name()] = new_default_logger;
+    }
+    default_logger_ = std::move(new_default_logger);
+}
+
+SPDLOG_INLINE void registry::set_tp(std::shared_ptr<thread_pool> tp)
+{
+    std::lock_guard<std::recursive_mutex> lock(tp_mutex_);
+    tp_ = std::move(tp);
+}
+
+SPDLOG_INLINE std::shared_ptr<thread_pool> registry::get_tp()
+{
+    std::lock_guard<std::recursive_mutex> lock(tp_mutex_);
+    return tp_;
+}
+
+// Set global formatter. Each sink in each logger will get a clone of this object
+SPDLOG_INLINE void registry::set_formatter(std::unique_ptr<formatter> formatter)
+{
+    std::lock_guard<std::mutex> lock(logger_map_mutex_);
+    formatter_ = std::move(formatter);
+    for (auto &l : loggers_)
+    {
+        l.second->set_formatter(formatter_->clone());
+    }
+}
+
+SPDLOG_INLINE void registry::enable_backtrace(size_t n_messages)
+{
+    std::lock_guard<std::mutex> lock(logger_map_mutex_);
+    backtrace_n_messages_ = n_messages;
+
+    for (auto &l : loggers_)
+    {
+        l.second->enable_backtrace(n_messages);
+    }
+}
+
+SPDLOG_INLINE void registry::disable_backtrace()
+{
+    std::lock_guard<std::mutex> lock(logger_map_mutex_);
+    backtrace_n_messages_ = 0;
+    for (auto &l : loggers_)
+    {
+        l.second->disable_backtrace();
+    }
+}
+
+SPDLOG_INLINE void registry::set_level(level::level_enum log_level)
+{
+    std::lock_guard<std::mutex> lock(logger_map_mutex_);
+    for (auto &l : loggers_)
+    {
+        l.second->set_level(log_level);
+    }
+    levels_.set_default(log_level);
+}
+
+SPDLOG_INLINE void registry::flush_on(level::level_enum log_level)
+{
+    std::lock_guard<std::mutex> lock(logger_map_mutex_);
+    for (auto &l : loggers_)
+    {
+        l.second->flush_on(log_level);
+    }
+    flush_level_ = log_level;
+}
+
+SPDLOG_INLINE void registry::flush_every(std::chrono::seconds interval)
+{
+    std::lock_guard<std::mutex> lock(flusher_mutex_);
+    auto clbk = [this]() { this->flush_all(); };
+    periodic_flusher_ = details::make_unique<periodic_worker>(clbk, interval);
+}
+
+SPDLOG_INLINE void registry::set_error_handler(void (*handler)(const std::string &msg))
+{
+    std::lock_guard<std::mutex> lock(logger_map_mutex_);
+    for (auto &l : loggers_)
+    {
+        l.second->set_error_handler(handler);
+    }
+    err_handler_ = handler;
+}
+
+SPDLOG_INLINE void registry::apply_all(const std::function<void(const std::shared_ptr<logger>)> &fun)
+{
+    std::lock_guard<std::mutex> lock(logger_map_mutex_);
+    for (auto &l : loggers_)
+    {
+        fun(l.second);
+    }
+}
+
+SPDLOG_INLINE void registry::flush_all()
+{
+    std::lock_guard<std::mutex> lock(logger_map_mutex_);
+    for (auto &l : loggers_)
+    {
+        l.second->flush();
+    }
+}
+
+SPDLOG_INLINE void registry::drop(const std::string &logger_name)
+{
+    std::lock_guard<std::mutex> lock(logger_map_mutex_);
+    loggers_.erase(logger_name);
+    if (default_logger_ && default_logger_->name() == logger_name)
+    {
+        default_logger_.reset();
+    }
+}
+
+SPDLOG_INLINE void registry::drop_all()
+{
+    std::lock_guard<std::mutex> lock(logger_map_mutex_);
+    loggers_.clear();
+    default_logger_.reset();
+}
+
+// clean all resources and threads started by the registry
+SPDLOG_INLINE void registry::shutdown()
+{
+    {
+        std::lock_guard<std::mutex> lock(flusher_mutex_);
+        periodic_flusher_.reset();
+    }
+
+    drop_all();
+
+    {
+        std::lock_guard<std::recursive_mutex> lock(tp_mutex_);
+        tp_.reset();
+    }
+}
+
+SPDLOG_INLINE std::recursive_mutex &registry::tp_mutex()
+{
+    return tp_mutex_;
+}
+
+SPDLOG_INLINE void registry::set_automatic_registration(bool automatic_registration)
+{
+    std::lock_guard<std::mutex> lock(logger_map_mutex_);
+    automatic_registration_ = automatic_registration;
+}
+
+SPDLOG_INLINE void registry::update_levels(cfg::log_levels levels)
+{
+    std::lock_guard<std::mutex> lock(logger_map_mutex_);
+    levels_ = std::move(levels);
+    for (auto &l : loggers_)
+    {
+        auto &logger = l.second;
+        logger->set_level(levels_.get(logger->name()));
+    }
+}
+
+SPDLOG_INLINE registry &registry::instance()
+{
+    static registry s_instance;
+    return s_instance;
+}
+
+SPDLOG_INLINE void registry::throw_if_exists_(const std::string &logger_name)
+{
+    if (loggers_.find(logger_name) != loggers_.end())
+    {
+        throw_spdlog_ex("logger with name '" + logger_name + "' already exists");
+    }
+}
+
+SPDLOG_INLINE void registry::register_logger_(std::shared_ptr<logger> new_logger)
+{
+    auto logger_name = new_logger->name();
+    throw_if_exists_(logger_name);
+    loggers_[logger_name] = std::move(new_logger);
+}
+
+} // namespace details
+} // namespace spdlog
--- a/src/spdlog/details/registry.h
+++ b/src/spdlog/details/registry.h
@@ -0,0 +1,112 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+// Loggers registry of unique name->logger pointer
+// An attempt to create a logger with an already existing name will result with spdlog_ex exception.
+// If user requests a non existing logger, nullptr will be returned
+// This class is thread safe
+
+#include <spdlog/common.h>
+#include <spdlog/cfg/log_levels.h>
+
+#include <chrono>
+#include <functional>
+#include <memory>
+#include <string>
+#include <unordered_map>
+#include <mutex>
+
+namespace spdlog {
+class logger;
+
+namespace details {
+class thread_pool;
+class periodic_worker;
+
+class SPDLOG_API registry
+{
+public:
+    registry(const registry &) = delete;
+    registry &operator=(const registry &) = delete;
+
+    void register_logger(std::shared_ptr<logger> new_logger);
+    void initialize_logger(std::shared_ptr<logger> new_logger);
+    std::shared_ptr<logger> get(const std::string &logger_name);
+    std::shared_ptr<logger> default_logger();
+
+    // Return raw ptr to the default logger.
+    // To be used directly by the spdlog default api (e.g. spdlog::info)
+    // This make the default API faster, but cannot be used concurrently with set_default_logger().
+    // e.g do not call set_default_logger() from one thread while calling spdlog::info() from another.
+    logger *get_default_raw();
+
+    // set default logger.
+    // default logger is stored in default_logger_ (for faster retrieval) and in the loggers_ map.
+    void set_default_logger(std::shared_ptr<logger> new_default_logger);
+
+    void set_tp(std::shared_ptr<thread_pool> tp);
+
+    std::shared_ptr<thread_pool> get_tp();
+
+    // Set global formatter. Each sink in each logger will get a clone of this object
+    void set_formatter(std::unique_ptr<formatter> formatter);
+
+    void enable_backtrace(size_t n_messages);
+
+    void disable_backtrace();
+
+    void set_level(level::level_enum log_level);
+
+    void flush_on(level::level_enum log_level);
+
+    void flush_every(std::chrono::seconds interval);
+
+    void set_error_handler(void (*handler)(const std::string &msg));
+
+    void apply_all(const std::function<void(const std::shared_ptr<logger>)> &fun);
+
+    void flush_all();
+
+    void drop(const std::string &logger_name);
+
+    void drop_all();
+
+    // clean all resources and threads started by the registry
+    void shutdown();
+
+    std::recursive_mutex &tp_mutex();
+
+    void set_automatic_registration(bool automatic_registration);
+
+    void update_levels(cfg::log_levels levels);
+
+    static registry &instance();
+
+private:
+    registry();
+    ~registry();
+
+    void throw_if_exists_(const std::string &logger_name);
+    void register_logger_(std::shared_ptr<logger> new_logger);
+    std::mutex logger_map_mutex_, flusher_mutex_;
+    std::recursive_mutex tp_mutex_;
+    std::unordered_map<std::string, std::shared_ptr<logger>> loggers_;
+    cfg::log_levels levels_;
+    std::unique_ptr<formatter> formatter_;
+    level::level_enum flush_level_ = level::off;
+    void (*err_handler_)(const std::string &msg);
+    std::shared_ptr<thread_pool> tp_;
+    std::unique_ptr<periodic_worker> periodic_flusher_;
+    std::shared_ptr<logger> default_logger_;
+    bool automatic_registration_ = true;
+    size_t backtrace_n_messages_ = 0;
+};
+
+} // namespace details
+} // namespace spdlog
+
+#ifdef SPDLOG_HEADER_ONLY
+#include "registry-inl.h"
+#endif
--- a/src/spdlog/details/synchronous_factory.h
+++ b/src/spdlog/details/synchronous_factory.h
@@ -0,0 +1,24 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include "registry.h"
+
+namespace spdlog {
+
+// Default logger factory-  creates synchronous loggers
+class logger;
+
+struct synchronous_factory
+{
+    template<typename Sink, typename... SinkArgs>
+    static std::shared_ptr<spdlog::logger> create(std::string logger_name, SinkArgs &&... args)
+    {
+        auto sink = std::make_shared<Sink>(std::forward<SinkArgs>(args)...);
+        auto new_logger = std::make_shared<spdlog::logger>(std::move(logger_name), std::move(sink));
+        details::registry::instance().initialize_logger(new_logger);
+        return new_logger;
+    }
+};
+} // namespace spdlog
--- a/src/spdlog/details/tcp_client-windows.h
+++ b/src/spdlog/details/tcp_client-windows.h
@@ -0,0 +1,175 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#define WIN32_LEAN_AND_MEAN
+// tcp client helper
+#include <spdlog/common.h>
+#include <spdlog/details/os.h>
+
+#include <windows.h>
+#include <winsock2.h>
+#include <ws2tcpip.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string>
+
+#pragma comment(lib, "Ws2_32.lib")
+#pragma comment(lib, "Mswsock.lib")
+#pragma comment(lib, "AdvApi32.lib")
+
+namespace spdlog {
+namespace details {
+class tcp_client
+{
+    SOCKET socket_ = INVALID_SOCKET;
+
+    static bool winsock_initialized_()
+    {
+        SOCKET s = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
+        if (s == INVALID_SOCKET)
+        {
+            return false;
+        }
+        else
+        {
+            closesocket(s);
+            return true;
+        }
+    }
+
+    static void init_winsock_()
+    {
+        WSADATA wsaData;
+        auto rv = WSAStartup(MAKEWORD(2, 2), &wsaData);
+        if (rv != 0)
+        {
+            throw_winsock_error_("WSAStartup failed", ::WSAGetLastError());
+        }
+    }
+
+    static void throw_winsock_error_(const std::string &msg, int last_error)
+    {
+        char buf[512];
+        ::FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, NULL, last_error,
+            MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), buf, (sizeof(buf) / sizeof(char)), NULL);
+
+        throw_spdlog_ex(fmt::format("tcp_sink - {}: {}", msg, buf));
+    }
+
+public:
+    bool is_connected() const
+    {
+        return socket_ != INVALID_SOCKET;
+    }
+
+    void close()
+    {
+        ::closesocket(socket_);
+        socket_ = INVALID_SOCKET;
+        WSACleanup();
+    }
+
+    SOCKET fd() const
+    {
+        return socket_;
+    }
+
+    ~tcp_client()
+    {
+        close();
+    }
+
+    // try to connect or throw on failure
+    void connect(const std::string &host, int port)
+    {
+        // initialize winsock if needed
+        if (!winsock_initialized_())
+        {
+            init_winsock_();
+        }
+
+        if (is_connected())
+        {
+            close();
+        }
+        struct addrinfo hints
+        {};
+        ZeroMemory(&hints, sizeof(hints));
+
+        hints.ai_family = AF_INET;       // IPv4
+        hints.ai_socktype = SOCK_STREAM; // TCP
+        hints.ai_flags = AI_NUMERICSERV; // port passed as as numeric value
+        hints.ai_protocol = 0;
+
+        auto port_str = std::to_string(port);
+        struct addrinfo *addrinfo_result;
+        auto rv = ::getaddrinfo(host.c_str(), port_str.c_str(), &hints, &addrinfo_result);
+        int last_error = 0;
+        if (rv != 0)
+        {
+            last_error = ::WSAGetLastError();
+            WSACleanup();
+            throw_winsock_error_("getaddrinfo failed", last_error);
+        }
+
+        // Try each address until we successfully connect(2).
+
+        for (auto *rp = addrinfo_result; rp != nullptr; rp = rp->ai_next)
+        {
+            socket_ = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
+            if (socket_ == INVALID_SOCKET)
+            {
+                last_error = ::WSAGetLastError();
+                WSACleanup();
+                continue;
+            }
+            if (::connect(socket_, rp->ai_addr, (int)rp->ai_addrlen) == 0)
+            {
+                break;
+            }
+            else
+            {
+                last_error = ::WSAGetLastError();
+                close();
+            }
+        }
+        ::freeaddrinfo(addrinfo_result);
+        if (socket_ == INVALID_SOCKET)
+        {
+            WSACleanup();
+            throw_winsock_error_("connect failed", last_error);
+        }
+
+        // set TCP_NODELAY
+        int enable_flag = 1;
+        ::setsockopt(socket_, IPPROTO_TCP, TCP_NODELAY, (char *)&enable_flag, sizeof(enable_flag));
+    }
+
+    // Send exactly n_bytes of the given data.
+    // On error close the connection and throw.
+    void send(const char *data, size_t n_bytes)
+    {
+        size_t bytes_sent = 0;
+        while (bytes_sent < n_bytes)
+        {
+            const int send_flags = 0;
+            auto write_result = ::send(socket_, data + bytes_sent, (int)(n_bytes - bytes_sent), send_flags);
+            if (write_result == SOCKET_ERROR)
+            {
+                int last_error = ::WSAGetLastError();
+                close();
+                throw_winsock_error_("send failed", last_error);
+            }
+
+            if (write_result == 0) // (probably should not happen but in any case..)
+            {
+                break;
+            }
+            bytes_sent += static_cast<size_t>(write_result);
+        }
+    }
+};
+} // namespace details
+} // namespace spdlog
--- a/src/spdlog/details/tcp_client.h
+++ b/src/spdlog/details/tcp_client.h
@@ -0,0 +1,145 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#ifdef _WIN32
+#error include tcp_client-windows.h instead
+#endif
+
+// tcp client helper
+#include <spdlog/common.h>
+#include <spdlog/details/os.h>
+
+#include <sys/socket.h>
+#include <arpa/inet.h>
+#include <unistd.h>
+#include <netdb.h>
+#include <netinet/tcp.h>
+
+#include <string>
+
+namespace spdlog {
+namespace details {
+class tcp_client
+{
+    int socket_ = -1;
+
+public:
+    bool is_connected() const
+    {
+        return socket_ != -1;
+    }
+
+    void close()
+    {
+        if (is_connected())
+        {
+            ::close(socket_);
+            socket_ = -1;
+        }
+    }
+
+    int fd() const
+    {
+        return socket_;
+    }
+
+    ~tcp_client()
+    {
+        close();
+    }
+
+    // try to connect or throw on failure
+    void connect(const std::string &host, int port)
+    {
+        close();
+        struct addrinfo hints
+        {};
+        memset(&hints, 0, sizeof(struct addrinfo));
+        hints.ai_family = AF_INET;       // IPv4
+        hints.ai_socktype = SOCK_STREAM; // TCP
+        hints.ai_flags = AI_NUMERICSERV; // port passed as as numeric value
+        hints.ai_protocol = 0;
+
+        auto port_str = std::to_string(port);
+        struct addrinfo *addrinfo_result;
+        auto rv = ::getaddrinfo(host.c_str(), port_str.c_str(), &hints, &addrinfo_result);
+        if (rv != 0)
+        {
+            auto msg = fmt::format("::getaddrinfo failed: {}", gai_strerror(rv));
+            throw_spdlog_ex(msg);
+        }
+
+        // Try each address until we successfully connect(2).
+        int last_errno = 0;
+        for (auto *rp = addrinfo_result; rp != nullptr; rp = rp->ai_next)
+        {
+            int const flags = SOCK_CLOEXEC;
+            socket_ = ::socket(rp->ai_family, rp->ai_socktype | flags, rp->ai_protocol);
+            if (socket_ == -1)
+            {
+                last_errno = errno;
+                continue;
+            }
+            rv = ::connect(socket_, rp->ai_addr, rp->ai_addrlen);
+            if (rv == 0)
+            {
+                break;
+            }
+            else
+            {
+                last_errno = errno;
+                ::close(socket_);
+                socket_ = -1;
+            }
+        }
+        ::freeaddrinfo(addrinfo_result);
+        if (socket_ == -1)
+        {
+            throw_spdlog_ex("::connect failed", last_errno);
+        }
+
+        // set TCP_NODELAY
+        int enable_flag = 1;
+        ::setsockopt(socket_, IPPROTO_TCP, TCP_NODELAY, (char *)&enable_flag, sizeof(enable_flag));
+
+        // prevent sigpipe on systems where MSG_NOSIGNAL is not available
+#if defined(SO_NOSIGPIPE) && !defined(MSG_NOSIGNAL)
+        ::setsockopt(socket_, SOL_SOCKET, SO_NOSIGPIPE, (char *)&enable_flag, sizeof(enable_flag));
+#endif
+
+#if !defined(SO_NOSIGPIPE) && !defined(MSG_NOSIGNAL)
+#error "tcp_sink would raise SIGPIPE since niether SO_NOSIGPIPE nor MSG_NOSIGNAL are available"
+#endif
+    }
+
+    // Send exactly n_bytes of the given data.
+    // On error close the connection and throw.
+    void send(const char *data, size_t n_bytes)
+    {
+        size_t bytes_sent = 0;
+        while (bytes_sent < n_bytes)
+        {
+#if defined(MSG_NOSIGNAL)
+            const int send_flags = MSG_NOSIGNAL;
+#else
+            const int send_flags = 0;
+#endif
+            auto write_result = ::send(socket_, data + bytes_sent, n_bytes - bytes_sent, send_flags);
+            if (write_result < 0)
+            {
+                close();
+                throw_spdlog_ex("write(2) failed", errno);
+            }
+
+            if (write_result == 0) // (probably should not happen but in any case..)
+            {
+                break;
+            }
+            bytes_sent += static_cast<size_t>(write_result);
+        }
+    }
+};
+} // namespace details
+} // namespace spdlog
--- a/src/spdlog/details/thread_pool-inl.h
+++ b/src/spdlog/details/thread_pool-inl.h
@@ -0,0 +1,124 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#ifndef SPDLOG_HEADER_ONLY
+#include <spdlog/details/thread_pool.h>
+#endif
+
+#include <spdlog/common.h>
+#include <cassert>
+
+namespace spdlog {
+namespace details {
+
+SPDLOG_INLINE thread_pool::thread_pool(size_t q_max_items, size_t threads_n, std::function<void()> on_thread_start)
+    : q_(q_max_items)
+{
+    if (threads_n == 0 || threads_n > 1000)
+    {
+        throw_spdlog_ex("spdlog::thread_pool(): invalid threads_n param (valid "
+                        "range is 1-1000)");
+    }
+    for (size_t i = 0; i < threads_n; i++)
+    {
+        threads_.emplace_back([this, on_thread_start] {
+            on_thread_start();
+            this->thread_pool::worker_loop_();
+        });
+    }
+}
+
+SPDLOG_INLINE thread_pool::thread_pool(size_t q_max_items, size_t threads_n)
+    : thread_pool(q_max_items, threads_n, [] {})
+{}
+
+// message all threads to terminate gracefully join them
+SPDLOG_INLINE thread_pool::~thread_pool()
+{
+    SPDLOG_TRY
+    {
+        for (size_t i = 0; i < threads_.size(); i++)
+        {
+            post_async_msg_(async_msg(async_msg_type::terminate), async_overflow_policy::block);
+        }
+
+        for (auto &t : threads_)
+        {
+            t.join();
+        }
+    }
+    SPDLOG_CATCH_ALL() {}
+}
+
+void SPDLOG_INLINE thread_pool::post_log(async_logger_ptr &&worker_ptr, const details::log_msg &msg, async_overflow_policy overflow_policy)
+{
+    async_msg async_m(std::move(worker_ptr), async_msg_type::log, msg);
+    post_async_msg_(std::move(async_m), overflow_policy);
+}
+
+void SPDLOG_INLINE thread_pool::post_flush(async_logger_ptr &&worker_ptr, async_overflow_policy overflow_policy)
+{
+    post_async_msg_(async_msg(std::move(worker_ptr), async_msg_type::flush), overflow_policy);
+}
+
+size_t SPDLOG_INLINE thread_pool::overrun_counter()
+{
+    return q_.overrun_counter();
+}
+
+void SPDLOG_INLINE thread_pool::post_async_msg_(async_msg &&new_msg, async_overflow_policy overflow_policy)
+{
+    if (overflow_policy == async_overflow_policy::block)
+    {
+        q_.enqueue(std::move(new_msg));
+    }
+    else
+    {
+        q_.enqueue_nowait(std::move(new_msg));
+    }
+}
+
+void SPDLOG_INLINE thread_pool::worker_loop_()
+{
+    while (process_next_msg_()) {}
+}
+
+// process next message in the queue
+// return true if this thread should still be active (while no terminate msg
+// was received)
+bool SPDLOG_INLINE thread_pool::process_next_msg_()
+{
+    async_msg incoming_async_msg;
+    bool dequeued = q_.dequeue_for(incoming_async_msg, std::chrono::seconds(10));
+    if (!dequeued)
+    {
+        return true;
+    }
+
+    switch (incoming_async_msg.msg_type)
+    {
+    case async_msg_type::log: {
+        incoming_async_msg.worker_ptr->backend_sink_it_(incoming_async_msg);
+        return true;
+    }
+    case async_msg_type::flush: {
+        incoming_async_msg.worker_ptr->backend_flush_();
+        return true;
+    }
+
+    case async_msg_type::terminate: {
+        return false;
+    }
+
+    default: {
+        assert(false);
+    }
+    }
+
+    return true;
+}
+
+} // namespace details
+} // namespace spdlog
--- a/src/spdlog/details/thread_pool.h
+++ b/src/spdlog/details/thread_pool.h
@@ -0,0 +1,120 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include <spdlog/details/log_msg_buffer.h>
+#include <spdlog/details/mpmc_blocking_q.h>
+#include <spdlog/details/os.h>
+
+#include <chrono>
+#include <memory>
+#include <thread>
+#include <vector>
+#include <functional>
+
+namespace spdlog {
+class async_logger;
+
+namespace details {
+
+using async_logger_ptr = std::shared_ptr<spdlog::async_logger>;
+
+enum class async_msg_type
+{
+    log,
+    flush,
+    terminate
+};
+
+#include <spdlog/details/log_msg_buffer.h>
+// Async msg to move to/from the queue
+// Movable only. should never be copied
+struct async_msg : log_msg_buffer
+{
+    async_msg_type msg_type{async_msg_type::log};
+    async_logger_ptr worker_ptr;
+
+    async_msg() = default;
+    ~async_msg() = default;
+
+    // should only be moved in or out of the queue..
+    async_msg(const async_msg &) = delete;
+
+// support for vs2013 move
+#if defined(_MSC_VER) && _MSC_VER <= 1800
+    async_msg(async_msg &&other)
+        : log_msg_buffer(std::move(other))
+        , msg_type(other.msg_type)
+        , worker_ptr(std::move(other.worker_ptr))
+    {}
+
+    async_msg &operator=(async_msg &&other)
+    {
+        *static_cast<log_msg_buffer *>(this) = std::move(other);
+        msg_type = other.msg_type;
+        worker_ptr = std::move(other.worker_ptr);
+        return *this;
+    }
+#else // (_MSC_VER) && _MSC_VER <= 1800
+    async_msg(async_msg &&) = default;
+    async_msg &operator=(async_msg &&) = default;
+#endif
+
+    // construct from log_msg with given type
+    async_msg(async_logger_ptr &&worker, async_msg_type the_type, const details::log_msg &m)
+        : log_msg_buffer{m}
+        , msg_type{the_type}
+        , worker_ptr{std::move(worker)}
+    {}
+
+    async_msg(async_logger_ptr &&worker, async_msg_type the_type)
+        : log_msg_buffer{}
+        , msg_type{the_type}
+        , worker_ptr{std::move(worker)}
+    {}
+
+    explicit async_msg(async_msg_type the_type)
+        : async_msg{nullptr, the_type}
+    {}
+};
+
+class SPDLOG_API thread_pool
+{
+public:
+    using item_type = async_msg;
+    using q_type = details::mpmc_blocking_queue<item_type>;
+
+    thread_pool(size_t q_max_items, size_t threads_n, std::function<void()> on_thread_start);
+    thread_pool(size_t q_max_items, size_t threads_n);
+
+    // message all threads to terminate gracefully join them
+    ~thread_pool();
+
+    thread_pool(const thread_pool &) = delete;
+    thread_pool &operator=(thread_pool &&) = delete;
+
+    void post_log(async_logger_ptr &&worker_ptr, const details::log_msg &msg, async_overflow_policy overflow_policy);
+    void post_flush(async_logger_ptr &&worker_ptr, async_overflow_policy overflow_policy);
+    size_t overrun_counter();
+
+private:
+    q_type q_;
+
+    std::vector<std::thread> threads_;
+
+    void post_async_msg_(async_msg &&new_msg, async_overflow_policy overflow_policy);
+    void worker_loop_();
+
+    // process next message in the queue
+    // return true if this thread should still be active (while no terminate msg
+    // was received)
+    bool process_next_msg_();
+};
+
+} // namespace details
+} // namespace spdlog
+
+#ifdef SPDLOG_HEADER_ONLY
+#include "thread_pool-inl.h"
+#endif
--- a/src/spdlog/details/windows_include.h
+++ b/src/spdlog/details/windows_include.h
@@ -0,0 +1,11 @@
+#pragma once
+
+#ifndef NOMINMAX
+#define NOMINMAX // prevent windows redefining min/max
+#endif
+
+#ifndef WIN32_LEAN_AND_MEAN
+#define WIN32_LEAN_AND_MEAN
+#endif
+
+#include <windows.h>
--- a/src/spdlog/fmt/bin_to_hex.h
+++ b/src/spdlog/fmt/bin_to_hex.h
@@ -0,0 +1,216 @@
+//
+// Copyright(c) 2015 Gabi Melman.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+//
+
+#pragma once
+
+#include <cctype>
+
+//
+// Support for logging binary data as hex
+// format flags:
+// {:X} - print in uppercase.
+// {:s} - don't separate each byte with space.
+// {:p} - don't print the position on each line start.
+// {:n} - don't split the output to lines.
+// {:a} - show ASCII if :n is not set
+
+//
+// Examples:
+//
+// std::vector<char> v(200, 0x0b);
+// logger->info("Some buffer {}", spdlog::to_hex(v));
+// char buf[128];
+// logger->info("Some buffer {:X}", spdlog::to_hex(std::begin(buf), std::end(buf)));
+// logger->info("Some buffer {:X}", spdlog::to_hex(std::begin(buf), std::end(buf), 16));
+
+namespace spdlog {
+namespace details {
+
+template<typename It>
+class dump_info
+{
+public:
+    dump_info(It range_begin, It range_end, size_t size_per_line)
+        : begin_(range_begin)
+        , end_(range_end)
+        , size_per_line_(size_per_line)
+    {}
+
+    It begin() const
+    {
+        return begin_;
+    }
+    It end() const
+    {
+        return end_;
+    }
+    size_t size_per_line() const
+    {
+        return size_per_line_;
+    }
+
+private:
+    It begin_, end_;
+    size_t size_per_line_;
+};
+} // namespace details
+
+// create a dump_info that wraps the given container
+template<typename Container>
+inline details::dump_info<typename Container::const_iterator> to_hex(const Container &container, size_t size_per_line = 32)
+{
+    static_assert(sizeof(typename Container::value_type) == 1, "sizeof(Container::value_type) != 1");
+    using Iter = typename Container::const_iterator;
+    return details::dump_info<Iter>(std::begin(container), std::end(container), size_per_line);
+}
+
+// create dump_info from ranges
+template<typename It>
+inline details::dump_info<It> to_hex(const It range_begin, const It range_end, size_t size_per_line = 32)
+{
+    return details::dump_info<It>(range_begin, range_end, size_per_line);
+}
+
+} // namespace spdlog
+
+namespace fmt {
+
+template<typename T>
+struct formatter<spdlog::details::dump_info<T>>
+{
+    const char delimiter = ' ';
+    bool put_newlines = true;
+    bool put_delimiters = true;
+    bool use_uppercase = false;
+    bool put_positions = true; // position on start of each line
+    bool show_ascii = false;
+
+    // parse the format string flags
+    template<typename ParseContext>
+    auto parse(ParseContext &ctx) -> decltype(ctx.begin())
+    {
+        auto it = ctx.begin();
+        while (it != ctx.end() && *it != '}')
+        {
+            switch (*it)
+            {
+            case 'X':
+                use_uppercase = true;
+                break;
+            case 's':
+                put_delimiters = false;
+                break;
+            case 'p':
+                put_positions = false;
+                break;
+            case 'n':
+                put_newlines = false;
+                show_ascii = false;
+                break;
+            case 'a':
+                if (put_newlines)
+                {
+                    show_ascii = true;
+                }
+                break;
+            }
+
+            ++it;
+        }
+        return it;
+    }
+
+    // format the given bytes range as hex
+    template<typename FormatContext, typename Container>
+    auto format(const spdlog::details::dump_info<Container> &the_range, FormatContext &ctx) -> decltype(ctx.out())
+    {
+        SPDLOG_CONSTEXPR const char *hex_upper = "0123456789ABCDEF";
+        SPDLOG_CONSTEXPR const char *hex_lower = "0123456789abcdef";
+        const char *hex_chars = use_uppercase ? hex_upper : hex_lower;
+
+#if FMT_VERSION < 60000
+        auto inserter = ctx.begin();
+#else
+        auto inserter = ctx.out();
+#endif
+
+        int size_per_line = static_cast<int>(the_range.size_per_line());
+        auto start_of_line = the_range.begin();
+        for (auto i = the_range.begin(); i != the_range.end(); i++)
+        {
+            auto ch = static_cast<unsigned char>(*i);
+
+            if (put_newlines && (i == the_range.begin() || i - start_of_line >= size_per_line))
+            {
+                if (show_ascii && i != the_range.begin())
+                {
+                    *inserter++ = delimiter;
+                    *inserter++ = delimiter;
+                    for (auto j = start_of_line; j < i; j++)
+                    {
+                        auto pc = static_cast<unsigned char>(*j);
+                        *inserter++ = std::isprint(pc) ? static_cast<char>(*j) : '.';
+                    }
+                }
+
+                put_newline(inserter, static_cast<size_t>(i - the_range.begin()));
+
+                // put first byte without delimiter in front of it
+                *inserter++ = hex_chars[(ch >> 4) & 0x0f];
+                *inserter++ = hex_chars[ch & 0x0f];
+                start_of_line = i;
+                continue;
+            }
+
+            if (put_delimiters)
+            {
+                *inserter++ = delimiter;
+            }
+
+            *inserter++ = hex_chars[(ch >> 4) & 0x0f];
+            *inserter++ = hex_chars[ch & 0x0f];
+        }
+        if (show_ascii) // add ascii to last line
+        {
+            if (the_range.end() - the_range.begin() > size_per_line)
+            {
+                auto blank_num = size_per_line - (the_range.end() - start_of_line);
+                while (blank_num-- > 0)
+                {
+                    *inserter++ = delimiter;
+                    *inserter++ = delimiter;
+                    if (put_delimiters)
+                    {
+                        *inserter++ = delimiter;
+                    }
+                }
+            }
+            *inserter++ = delimiter;
+            *inserter++ = delimiter;
+            for (auto j = start_of_line; j != the_range.end(); j++)
+            {
+                auto pc = static_cast<unsigned char>(*j);
+                *inserter++ = std::isprint(pc) ? static_cast<char>(*j) : '.';
+            }
+        }
+        return inserter;
+    }
+
+    // put newline(and position header)
+    template<typename It>
+    void put_newline(It inserter, std::size_t pos)
+    {
+#ifdef _WIN32
+        *inserter++ = '\r';
+#endif
+        *inserter++ = '\n';
+
+        if (put_positions)
+        {
+            fmt::format_to(inserter, "{:<04X}: ", pos);
+        }
+    }
+};
+} // namespace fmt
--- a/src/spdlog/fmt/bundled/LICENSE.rst
+++ b/src/spdlog/fmt/bundled/LICENSE.rst
@@ -0,0 +1,27 @@
+Copyright (c) 2012 - present, Victor Zverovich
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+--- Optional exception to the license ---
+
+As an exception, if, as a result of your compiling your source code, portions
+of this Software are embedded into a machine-executable object form of such
+source code, you may redistribute such embedded portions in such object form
+without including the above copyright and permission notices.
--- a/src/spdlog/fmt/bundled/chrono.h
+++ b/src/spdlog/fmt/bundled/chrono.h
--- a/src/spdlog/fmt/bundled/color.h
+++ b/src/spdlog/fmt/bundled/color.h
@@ -0,0 +1,568 @@
+// Formatting library for C++ - color support
+//
+// Copyright (c) 2018 - present, Victor Zverovich and fmt contributors
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_COLOR_H_
+#define FMT_COLOR_H_
+
+#include "format.h"
+
+FMT_BEGIN_NAMESPACE
+
+enum class color : uint32_t {
+  alice_blue = 0xF0F8FF,               // rgb(240,248,255)
+  antique_white = 0xFAEBD7,            // rgb(250,235,215)
+  aqua = 0x00FFFF,                     // rgb(0,255,255)
+  aquamarine = 0x7FFFD4,               // rgb(127,255,212)
+  azure = 0xF0FFFF,                    // rgb(240,255,255)
+  beige = 0xF5F5DC,                    // rgb(245,245,220)
+  bisque = 0xFFE4C4,                   // rgb(255,228,196)
+  black = 0x000000,                    // rgb(0,0,0)
+  blanched_almond = 0xFFEBCD,          // rgb(255,235,205)
+  blue = 0x0000FF,                     // rgb(0,0,255)
+  blue_violet = 0x8A2BE2,              // rgb(138,43,226)
+  brown = 0xA52A2A,                    // rgb(165,42,42)
+  burly_wood = 0xDEB887,               // rgb(222,184,135)
+  cadet_blue = 0x5F9EA0,               // rgb(95,158,160)
+  chartreuse = 0x7FFF00,               // rgb(127,255,0)
+  chocolate = 0xD2691E,                // rgb(210,105,30)
+  coral = 0xFF7F50,                    // rgb(255,127,80)
+  cornflower_blue = 0x6495ED,          // rgb(100,149,237)
+  cornsilk = 0xFFF8DC,                 // rgb(255,248,220)
+  crimson = 0xDC143C,                  // rgb(220,20,60)
+  cyan = 0x00FFFF,                     // rgb(0,255,255)
+  dark_blue = 0x00008B,                // rgb(0,0,139)
+  dark_cyan = 0x008B8B,                // rgb(0,139,139)
+  dark_golden_rod = 0xB8860B,          // rgb(184,134,11)
+  dark_gray = 0xA9A9A9,                // rgb(169,169,169)
+  dark_green = 0x006400,               // rgb(0,100,0)
+  dark_khaki = 0xBDB76B,               // rgb(189,183,107)
+  dark_magenta = 0x8B008B,             // rgb(139,0,139)
+  dark_olive_green = 0x556B2F,         // rgb(85,107,47)
+  dark_orange = 0xFF8C00,              // rgb(255,140,0)
+  dark_orchid = 0x9932CC,              // rgb(153,50,204)
+  dark_red = 0x8B0000,                 // rgb(139,0,0)
+  dark_salmon = 0xE9967A,              // rgb(233,150,122)
+  dark_sea_green = 0x8FBC8F,           // rgb(143,188,143)
+  dark_slate_blue = 0x483D8B,          // rgb(72,61,139)
+  dark_slate_gray = 0x2F4F4F,          // rgb(47,79,79)
+  dark_turquoise = 0x00CED1,           // rgb(0,206,209)
+  dark_violet = 0x9400D3,              // rgb(148,0,211)
+  deep_pink = 0xFF1493,                // rgb(255,20,147)
+  deep_sky_blue = 0x00BFFF,            // rgb(0,191,255)
+  dim_gray = 0x696969,                 // rgb(105,105,105)
+  dodger_blue = 0x1E90FF,              // rgb(30,144,255)
+  fire_brick = 0xB22222,               // rgb(178,34,34)
+  floral_white = 0xFFFAF0,             // rgb(255,250,240)
+  forest_green = 0x228B22,             // rgb(34,139,34)
+  fuchsia = 0xFF00FF,                  // rgb(255,0,255)
+  gainsboro = 0xDCDCDC,                // rgb(220,220,220)
+  ghost_white = 0xF8F8FF,              // rgb(248,248,255)
+  gold = 0xFFD700,                     // rgb(255,215,0)
+  golden_rod = 0xDAA520,               // rgb(218,165,32)
+  gray = 0x808080,                     // rgb(128,128,128)
+  green = 0x008000,                    // rgb(0,128,0)
+  green_yellow = 0xADFF2F,             // rgb(173,255,47)
+  honey_dew = 0xF0FFF0,                // rgb(240,255,240)
+  hot_pink = 0xFF69B4,                 // rgb(255,105,180)
+  indian_red = 0xCD5C5C,               // rgb(205,92,92)
+  indigo = 0x4B0082,                   // rgb(75,0,130)
+  ivory = 0xFFFFF0,                    // rgb(255,255,240)
+  khaki = 0xF0E68C,                    // rgb(240,230,140)
+  lavender = 0xE6E6FA,                 // rgb(230,230,250)
+  lavender_blush = 0xFFF0F5,           // rgb(255,240,245)
+  lawn_green = 0x7CFC00,               // rgb(124,252,0)
+  lemon_chiffon = 0xFFFACD,            // rgb(255,250,205)
+  light_blue = 0xADD8E6,               // rgb(173,216,230)
+  light_coral = 0xF08080,              // rgb(240,128,128)
+  light_cyan = 0xE0FFFF,               // rgb(224,255,255)
+  light_golden_rod_yellow = 0xFAFAD2,  // rgb(250,250,210)
+  light_gray = 0xD3D3D3,               // rgb(211,211,211)
+  light_green = 0x90EE90,              // rgb(144,238,144)
+  light_pink = 0xFFB6C1,               // rgb(255,182,193)
+  light_salmon = 0xFFA07A,             // rgb(255,160,122)
+  light_sea_green = 0x20B2AA,          // rgb(32,178,170)
+  light_sky_blue = 0x87CEFA,           // rgb(135,206,250)
+  light_slate_gray = 0x778899,         // rgb(119,136,153)
+  light_steel_blue = 0xB0C4DE,         // rgb(176,196,222)
+  light_yellow = 0xFFFFE0,             // rgb(255,255,224)
+  lime = 0x00FF00,                     // rgb(0,255,0)
+  lime_green = 0x32CD32,               // rgb(50,205,50)
+  linen = 0xFAF0E6,                    // rgb(250,240,230)
+  magenta = 0xFF00FF,                  // rgb(255,0,255)
+  maroon = 0x800000,                   // rgb(128,0,0)
+  medium_aquamarine = 0x66CDAA,        // rgb(102,205,170)
+  medium_blue = 0x0000CD,              // rgb(0,0,205)
+  medium_orchid = 0xBA55D3,            // rgb(186,85,211)
+  medium_purple = 0x9370DB,            // rgb(147,112,219)
+  medium_sea_green = 0x3CB371,         // rgb(60,179,113)
+  medium_slate_blue = 0x7B68EE,        // rgb(123,104,238)
+  medium_spring_green = 0x00FA9A,      // rgb(0,250,154)
+  medium_turquoise = 0x48D1CC,         // rgb(72,209,204)
+  medium_violet_red = 0xC71585,        // rgb(199,21,133)
+  midnight_blue = 0x191970,            // rgb(25,25,112)
+  mint_cream = 0xF5FFFA,               // rgb(245,255,250)
+  misty_rose = 0xFFE4E1,               // rgb(255,228,225)
+  moccasin = 0xFFE4B5,                 // rgb(255,228,181)
+  navajo_white = 0xFFDEAD,             // rgb(255,222,173)
+  navy = 0x000080,                     // rgb(0,0,128)
+  old_lace = 0xFDF5E6,                 // rgb(253,245,230)
+  olive = 0x808000,                    // rgb(128,128,0)
+  olive_drab = 0x6B8E23,               // rgb(107,142,35)
+  orange = 0xFFA500,                   // rgb(255,165,0)
+  orange_red = 0xFF4500,               // rgb(255,69,0)
+  orchid = 0xDA70D6,                   // rgb(218,112,214)
+  pale_golden_rod = 0xEEE8AA,          // rgb(238,232,170)
+  pale_green = 0x98FB98,               // rgb(152,251,152)
+  pale_turquoise = 0xAFEEEE,           // rgb(175,238,238)
+  pale_violet_red = 0xDB7093,          // rgb(219,112,147)
+  papaya_whip = 0xFFEFD5,              // rgb(255,239,213)
+  peach_puff = 0xFFDAB9,               // rgb(255,218,185)
+  peru = 0xCD853F,                     // rgb(205,133,63)
+  pink = 0xFFC0CB,                     // rgb(255,192,203)
+  plum = 0xDDA0DD,                     // rgb(221,160,221)
+  powder_blue = 0xB0E0E6,              // rgb(176,224,230)
+  purple = 0x800080,                   // rgb(128,0,128)
+  rebecca_purple = 0x663399,           // rgb(102,51,153)
+  red = 0xFF0000,                      // rgb(255,0,0)
+  rosy_brown = 0xBC8F8F,               // rgb(188,143,143)
+  royal_blue = 0x4169E1,               // rgb(65,105,225)
+  saddle_brown = 0x8B4513,             // rgb(139,69,19)
+  salmon = 0xFA8072,                   // rgb(250,128,114)
+  sandy_brown = 0xF4A460,              // rgb(244,164,96)
+  sea_green = 0x2E8B57,                // rgb(46,139,87)
+  sea_shell = 0xFFF5EE,                // rgb(255,245,238)
+  sienna = 0xA0522D,                   // rgb(160,82,45)
+  silver = 0xC0C0C0,                   // rgb(192,192,192)
+  sky_blue = 0x87CEEB,                 // rgb(135,206,235)
+  slate_blue = 0x6A5ACD,               // rgb(106,90,205)
+  slate_gray = 0x708090,               // rgb(112,128,144)
+  snow = 0xFFFAFA,                     // rgb(255,250,250)
+  spring_green = 0x00FF7F,             // rgb(0,255,127)
+  steel_blue = 0x4682B4,               // rgb(70,130,180)
+  tan = 0xD2B48C,                      // rgb(210,180,140)
+  teal = 0x008080,                     // rgb(0,128,128)
+  thistle = 0xD8BFD8,                  // rgb(216,191,216)
+  tomato = 0xFF6347,                   // rgb(255,99,71)
+  turquoise = 0x40E0D0,                // rgb(64,224,208)
+  violet = 0xEE82EE,                   // rgb(238,130,238)
+  wheat = 0xF5DEB3,                    // rgb(245,222,179)
+  white = 0xFFFFFF,                    // rgb(255,255,255)
+  white_smoke = 0xF5F5F5,              // rgb(245,245,245)
+  yellow = 0xFFFF00,                   // rgb(255,255,0)
+  yellow_green = 0x9ACD32              // rgb(154,205,50)
+};                                     // enum class color
+
+enum class terminal_color : uint8_t {
+  black = 30,
+  red,
+  green,
+  yellow,
+  blue,
+  magenta,
+  cyan,
+  white,
+  bright_black = 90,
+  bright_red,
+  bright_green,
+  bright_yellow,
+  bright_blue,
+  bright_magenta,
+  bright_cyan,
+  bright_white
+};
+
+enum class emphasis : uint8_t {
+  bold = 1,
+  italic = 1 << 1,
+  underline = 1 << 2,
+  strikethrough = 1 << 3
+};
+
+// rgb is a struct for red, green and blue colors.
+// Using the name "rgb" makes some editors show the color in a tooltip.
+struct rgb {
+  FMT_CONSTEXPR rgb() : r(0), g(0), b(0) {}
+  FMT_CONSTEXPR rgb(uint8_t r_, uint8_t g_, uint8_t b_) : r(r_), g(g_), b(b_) {}
+  FMT_CONSTEXPR rgb(uint32_t hex)
+      : r((hex >> 16) & 0xFF), g((hex >> 8) & 0xFF), b(hex & 0xFF) {}
+  FMT_CONSTEXPR rgb(color hex)
+      : r((uint32_t(hex) >> 16) & 0xFF),
+        g((uint32_t(hex) >> 8) & 0xFF),
+        b(uint32_t(hex) & 0xFF) {}
+  uint8_t r;
+  uint8_t g;
+  uint8_t b;
+};
+
+namespace internal {
+
+// color is a struct of either a rgb color or a terminal color.
+struct color_type {
+  FMT_CONSTEXPR color_type() FMT_NOEXCEPT : is_rgb(), value{} {}
+  FMT_CONSTEXPR color_type(color rgb_color) FMT_NOEXCEPT : is_rgb(true),
+                                                           value{} {
+    value.rgb_color = static_cast<uint32_t>(rgb_color);
+  }
+  FMT_CONSTEXPR color_type(rgb rgb_color) FMT_NOEXCEPT : is_rgb(true), value{} {
+    value.rgb_color = (static_cast<uint32_t>(rgb_color.r) << 16) |
+                      (static_cast<uint32_t>(rgb_color.g) << 8) | rgb_color.b;
+  }
+  FMT_CONSTEXPR color_type(terminal_color term_color) FMT_NOEXCEPT : is_rgb(),
+                                                                     value{} {
+    value.term_color = static_cast<uint8_t>(term_color);
+  }
+  bool is_rgb;
+  union color_union {
+    uint8_t term_color;
+    uint32_t rgb_color;
+  } value;
+};
+}  // namespace internal
+
+// Experimental text formatting support.
+class text_style {
+ public:
+  FMT_CONSTEXPR text_style(emphasis em = emphasis()) FMT_NOEXCEPT
+      : set_foreground_color(),
+        set_background_color(),
+        ems(em) {}
+
+  FMT_CONSTEXPR text_style& operator|=(const text_style& rhs) {
+    if (!set_foreground_color) {
+      set_foreground_color = rhs.set_foreground_color;
+      foreground_color = rhs.foreground_color;
+    } else if (rhs.set_foreground_color) {
+      if (!foreground_color.is_rgb || !rhs.foreground_color.is_rgb)
+        FMT_THROW(format_error("can't OR a terminal color"));
+      foreground_color.value.rgb_color |= rhs.foreground_color.value.rgb_color;
+    }
+
+    if (!set_background_color) {
+      set_background_color = rhs.set_background_color;
+      background_color = rhs.background_color;
+    } else if (rhs.set_background_color) {
+      if (!background_color.is_rgb || !rhs.background_color.is_rgb)
+        FMT_THROW(format_error("can't OR a terminal color"));
+      background_color.value.rgb_color |= rhs.background_color.value.rgb_color;
+    }
+
+    ems = static_cast<emphasis>(static_cast<uint8_t>(ems) |
+                                static_cast<uint8_t>(rhs.ems));
+    return *this;
+  }
+
+  friend FMT_CONSTEXPR text_style operator|(text_style lhs,
+                                            const text_style& rhs) {
+    return lhs |= rhs;
+  }
+
+  FMT_CONSTEXPR text_style& operator&=(const text_style& rhs) {
+    if (!set_foreground_color) {
+      set_foreground_color = rhs.set_foreground_color;
+      foreground_color = rhs.foreground_color;
+    } else if (rhs.set_foreground_color) {
+      if (!foreground_color.is_rgb || !rhs.foreground_color.is_rgb)
+        FMT_THROW(format_error("can't AND a terminal color"));
+      foreground_color.value.rgb_color &= rhs.foreground_color.value.rgb_color;
+    }
+
+    if (!set_background_color) {
+      set_background_color = rhs.set_background_color;
+      background_color = rhs.background_color;
+    } else if (rhs.set_background_color) {
+      if (!background_color.is_rgb || !rhs.background_color.is_rgb)
+        FMT_THROW(format_error("can't AND a terminal color"));
+      background_color.value.rgb_color &= rhs.background_color.value.rgb_color;
+    }
+
+    ems = static_cast<emphasis>(static_cast<uint8_t>(ems) &
+                                static_cast<uint8_t>(rhs.ems));
+    return *this;
+  }
+
+  friend FMT_CONSTEXPR text_style operator&(text_style lhs,
+                                            const text_style& rhs) {
+    return lhs &= rhs;
+  }
+
+  FMT_CONSTEXPR bool has_foreground() const FMT_NOEXCEPT {
+    return set_foreground_color;
+  }
+  FMT_CONSTEXPR bool has_background() const FMT_NOEXCEPT {
+    return set_background_color;
+  }
+  FMT_CONSTEXPR bool has_emphasis() const FMT_NOEXCEPT {
+    return static_cast<uint8_t>(ems) != 0;
+  }
+  FMT_CONSTEXPR internal::color_type get_foreground() const FMT_NOEXCEPT {
+    FMT_ASSERT(has_foreground(), "no foreground specified for this style");
+    return foreground_color;
+  }
+  FMT_CONSTEXPR internal::color_type get_background() const FMT_NOEXCEPT {
+    FMT_ASSERT(has_background(), "no background specified for this style");
+    return background_color;
+  }
+  FMT_CONSTEXPR emphasis get_emphasis() const FMT_NOEXCEPT {
+    FMT_ASSERT(has_emphasis(), "no emphasis specified for this style");
+    return ems;
+  }
+
+ private:
+  FMT_CONSTEXPR text_style(bool is_foreground,
+                           internal::color_type text_color) FMT_NOEXCEPT
+      : set_foreground_color(),
+        set_background_color(),
+        ems() {
+    if (is_foreground) {
+      foreground_color = text_color;
+      set_foreground_color = true;
+    } else {
+      background_color = text_color;
+      set_background_color = true;
+    }
+  }
+
+  friend FMT_CONSTEXPR_DECL text_style fg(internal::color_type foreground)
+      FMT_NOEXCEPT;
+  friend FMT_CONSTEXPR_DECL text_style bg(internal::color_type background)
+      FMT_NOEXCEPT;
+
+  internal::color_type foreground_color;
+  internal::color_type background_color;
+  bool set_foreground_color;
+  bool set_background_color;
+  emphasis ems;
+};
+
+FMT_CONSTEXPR text_style fg(internal::color_type foreground) FMT_NOEXCEPT {
+  return text_style(/*is_foreground=*/true, foreground);
+}
+
+FMT_CONSTEXPR text_style bg(internal::color_type background) FMT_NOEXCEPT {
+  return text_style(/*is_foreground=*/false, background);
+}
+
+FMT_CONSTEXPR text_style operator|(emphasis lhs, emphasis rhs) FMT_NOEXCEPT {
+  return text_style(lhs) | rhs;
+}
+
+namespace internal {
+
+template <typename Char> struct ansi_color_escape {
+  FMT_CONSTEXPR ansi_color_escape(internal::color_type text_color,
+                                  const char* esc) FMT_NOEXCEPT {
+    // If we have a terminal color, we need to output another escape code
+    // sequence.
+    if (!text_color.is_rgb) {
+      bool is_background = esc == internal::data::background_color;
+      uint32_t value = text_color.value.term_color;
+      // Background ASCII codes are the same as the foreground ones but with
+      // 10 more.
+      if (is_background) value += 10u;
+
+      std::size_t index = 0;
+      buffer[index++] = static_cast<Char>('\x1b');
+      buffer[index++] = static_cast<Char>('[');
+
+      if (value >= 100u) {
+        buffer[index++] = static_cast<Char>('1');
+        value %= 100u;
+      }
+      buffer[index++] = static_cast<Char>('0' + value / 10u);
+      buffer[index++] = static_cast<Char>('0' + value % 10u);
+
+      buffer[index++] = static_cast<Char>('m');
+      buffer[index++] = static_cast<Char>('\0');
+      return;
+    }
+
+    for (int i = 0; i < 7; i++) {
+      buffer[i] = static_cast<Char>(esc[i]);
+    }
+    rgb color(text_color.value.rgb_color);
+    to_esc(color.r, buffer + 7, ';');
+    to_esc(color.g, buffer + 11, ';');
+    to_esc(color.b, buffer + 15, 'm');
+    buffer[19] = static_cast<Char>(0);
+  }
+  FMT_CONSTEXPR ansi_color_escape(emphasis em) FMT_NOEXCEPT {
+    uint8_t em_codes[4] = {};
+    uint8_t em_bits = static_cast<uint8_t>(em);
+    if (em_bits & static_cast<uint8_t>(emphasis::bold)) em_codes[0] = 1;
+    if (em_bits & static_cast<uint8_t>(emphasis::italic)) em_codes[1] = 3;
+    if (em_bits & static_cast<uint8_t>(emphasis::underline)) em_codes[2] = 4;
+    if (em_bits & static_cast<uint8_t>(emphasis::strikethrough))
+      em_codes[3] = 9;
+
+    std::size_t index = 0;
+    for (int i = 0; i < 4; ++i) {
+      if (!em_codes[i]) continue;
+      buffer[index++] = static_cast<Char>('\x1b');
+      buffer[index++] = static_cast<Char>('[');
+      buffer[index++] = static_cast<Char>('0' + em_codes[i]);
+      buffer[index++] = static_cast<Char>('m');
+    }
+    buffer[index++] = static_cast<Char>(0);
+  }
+  FMT_CONSTEXPR operator const Char*() const FMT_NOEXCEPT { return buffer; }
+
+  FMT_CONSTEXPR const Char* begin() const FMT_NOEXCEPT { return buffer; }
+  FMT_CONSTEXPR const Char* end() const FMT_NOEXCEPT {
+    return buffer + std::char_traits<Char>::length(buffer);
+  }
+
+ private:
+  Char buffer[7u + 3u * 4u + 1u];
+
+  static FMT_CONSTEXPR void to_esc(uint8_t c, Char* out,
+                                   char delimiter) FMT_NOEXCEPT {
+    out[0] = static_cast<Char>('0' + c / 100);
+    out[1] = static_cast<Char>('0' + c / 10 % 10);
+    out[2] = static_cast<Char>('0' + c % 10);
+    out[3] = static_cast<Char>(delimiter);
+  }
+};
+
+template <typename Char>
+FMT_CONSTEXPR ansi_color_escape<Char> make_foreground_color(
+    internal::color_type foreground) FMT_NOEXCEPT {
+  return ansi_color_escape<Char>(foreground, internal::data::foreground_color);
+}
+
+template <typename Char>
+FMT_CONSTEXPR ansi_color_escape<Char> make_background_color(
+    internal::color_type background) FMT_NOEXCEPT {
+  return ansi_color_escape<Char>(background, internal::data::background_color);
+}
+
+template <typename Char>
+FMT_CONSTEXPR ansi_color_escape<Char> make_emphasis(emphasis em) FMT_NOEXCEPT {
+  return ansi_color_escape<Char>(em);
+}
+
+template <typename Char>
+inline void fputs(const Char* chars, FILE* stream) FMT_NOEXCEPT {
+  std::fputs(chars, stream);
+}
+
+template <>
+inline void fputs<wchar_t>(const wchar_t* chars, FILE* stream) FMT_NOEXCEPT {
+  std::fputws(chars, stream);
+}
+
+template <typename Char> inline void reset_color(FILE* stream) FMT_NOEXCEPT {
+  fputs(internal::data::reset_color, stream);
+}
+
+template <> inline void reset_color<wchar_t>(FILE* stream) FMT_NOEXCEPT {
+  fputs(internal::data::wreset_color, stream);
+}
+
+template <typename Char>
+inline void reset_color(basic_memory_buffer<Char>& buffer) FMT_NOEXCEPT {
+  const char* begin = data::reset_color;
+  const char* end = begin + sizeof(data::reset_color) - 1;
+  buffer.append(begin, end);
+}
+
+template <typename Char>
+void vformat_to(basic_memory_buffer<Char>& buf, const text_style& ts,
+                basic_string_view<Char> format_str,
+                basic_format_args<buffer_context<Char>> args) {
+  bool has_style = false;
+  if (ts.has_emphasis()) {
+    has_style = true;
+    auto emphasis = internal::make_emphasis<Char>(ts.get_emphasis());
+    buf.append(emphasis.begin(), emphasis.end());
+  }
+  if (ts.has_foreground()) {
+    has_style = true;
+    auto foreground =
+        internal::make_foreground_color<Char>(ts.get_foreground());
+    buf.append(foreground.begin(), foreground.end());
+  }
+  if (ts.has_background()) {
+    has_style = true;
+    auto background =
+        internal::make_background_color<Char>(ts.get_background());
+    buf.append(background.begin(), background.end());
+  }
+  internal::vformat_to(buf, format_str, args);
+  if (has_style) internal::reset_color<Char>(buf);
+}
+}  // namespace internal
+
+template <typename S, typename Char = char_t<S>>
+void vprint(std::FILE* f, const text_style& ts, const S& format,
+            basic_format_args<buffer_context<Char>> args) {
+  basic_memory_buffer<Char> buf;
+  internal::vformat_to(buf, ts, to_string_view(format), args);
+  buf.push_back(Char(0));
+  internal::fputs(buf.data(), f);
+}
+
+/**
+  Formats a string and prints it to the specified file stream using ANSI
+  escape sequences to specify text formatting.
+  Example:
+    fmt::print(fmt::emphasis::bold | fg(fmt::color::red),
+               "Elapsed time: {0:.2f} seconds", 1.23);
+ */
+template <typename S, typename... Args,
+          FMT_ENABLE_IF(internal::is_string<S>::value)>
+void print(std::FILE* f, const text_style& ts, const S& format_str,
+           const Args&... args) {
+  internal::check_format_string<Args...>(format_str);
+  using context = buffer_context<char_t<S>>;
+  format_arg_store<context, Args...> as{args...};
+  vprint(f, ts, format_str, basic_format_args<context>(as));
+}
+
+/**
+  Formats a string and prints it to stdout using ANSI escape sequences to
+  specify text formatting.
+  Example:
+    fmt::print(fmt::emphasis::bold | fg(fmt::color::red),
+               "Elapsed time: {0:.2f} seconds", 1.23);
+ */
+template <typename S, typename... Args,
+          FMT_ENABLE_IF(internal::is_string<S>::value)>
+void print(const text_style& ts, const S& format_str, const Args&... args) {
+  return print(stdout, ts, format_str, args...);
+}
+
+template <typename S, typename Char = char_t<S>>
+inline std::basic_string<Char> vformat(
+    const text_style& ts, const S& format_str,
+    basic_format_args<buffer_context<type_identity_t<Char>>> args) {
+  basic_memory_buffer<Char> buf;
+  internal::vformat_to(buf, ts, to_string_view(format_str), args);
+  return fmt::to_string(buf);
+}
+
+/**
+  \rst
+  Formats arguments and returns the result as a string using ANSI
+  escape sequences to specify text formatting.
+
+  **Example**::
+
+    #include <fmt/color.h>
+    std::string message = fmt::format(fmt::emphasis::bold | fg(fmt::color::red),
+                                      "The answer is {}", 42);
+  \endrst
+*/
+template <typename S, typename... Args, typename Char = char_t<S>>
+inline std::basic_string<Char> format(const text_style& ts, const S& format_str,
+                                      const Args&... args) {
+  return vformat(ts, to_string_view(format_str),
+                 internal::make_args_checked<Args...>(format_str, args...));
+}
+
+FMT_END_NAMESPACE
+
+#endif  // FMT_COLOR_H_
--- a/src/spdlog/fmt/bundled/compile.h
+++ b/src/spdlog/fmt/bundled/compile.h
@@ -0,0 +1,595 @@
+// Formatting library for C++ - experimental format string compilation
+//
+// Copyright (c) 2012 - present, Victor Zverovich and fmt contributors
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_COMPILE_H_
+#define FMT_COMPILE_H_
+
+#include <vector>
+
+#include "format.h"
+
+FMT_BEGIN_NAMESPACE
+namespace internal {
+
+// Part of a compiled format string. It can be either literal text or a
+// replacement field.
+template <typename Char> struct format_part {
+  enum class kind { arg_index, arg_name, text, replacement };
+
+  struct replacement {
+    arg_ref<Char> arg_id;
+    dynamic_format_specs<Char> specs;
+  };
+
+  kind part_kind;
+  union value {
+    int arg_index;
+    basic_string_view<Char> str;
+    replacement repl;
+
+    FMT_CONSTEXPR value(int index = 0) : arg_index(index) {}
+    FMT_CONSTEXPR value(basic_string_view<Char> s) : str(s) {}
+    FMT_CONSTEXPR value(replacement r) : repl(r) {}
+  } val;
+  // Position past the end of the argument id.
+  const Char* arg_id_end = nullptr;
+
+  FMT_CONSTEXPR format_part(kind k = kind::arg_index, value v = {})
+      : part_kind(k), val(v) {}
+
+  static FMT_CONSTEXPR format_part make_arg_index(int index) {
+    return format_part(kind::arg_index, index);
+  }
+  static FMT_CONSTEXPR format_part make_arg_name(basic_string_view<Char> name) {
+    return format_part(kind::arg_name, name);
+  }
+  static FMT_CONSTEXPR format_part make_text(basic_string_view<Char> text) {
+    return format_part(kind::text, text);
+  }
+  static FMT_CONSTEXPR format_part make_replacement(replacement repl) {
+    return format_part(kind::replacement, repl);
+  }
+};
+
+template <typename Char> struct part_counter {
+  unsigned num_parts = 0;
+
+  FMT_CONSTEXPR void on_text(const Char* begin, const Char* end) {
+    if (begin != end) ++num_parts;
+  }
+
+  FMT_CONSTEXPR void on_arg_id() { ++num_parts; }
+  FMT_CONSTEXPR void on_arg_id(int) { ++num_parts; }
+  FMT_CONSTEXPR void on_arg_id(basic_string_view<Char>) { ++num_parts; }
+
+  FMT_CONSTEXPR void on_replacement_field(const Char*) {}
+
+  FMT_CONSTEXPR const Char* on_format_specs(const Char* begin,
+                                            const Char* end) {
+    // Find the matching brace.
+    unsigned brace_counter = 0;
+    for (; begin != end; ++begin) {
+      if (*begin == '{') {
+        ++brace_counter;
+      } else if (*begin == '}') {
+        if (brace_counter == 0u) break;
+        --brace_counter;
+      }
+    }
+    return begin;
+  }
+
+  FMT_CONSTEXPR void on_error(const char*) {}
+};
+
+// Counts the number of parts in a format string.
+template <typename Char>
+FMT_CONSTEXPR unsigned count_parts(basic_string_view<Char> format_str) {
+  part_counter<Char> counter;
+  parse_format_string<true>(format_str, counter);
+  return counter.num_parts;
+}
+
+template <typename Char, typename PartHandler>
+class format_string_compiler : public error_handler {
+ private:
+  using part = format_part<Char>;
+
+  PartHandler handler_;
+  part part_;
+  basic_string_view<Char> format_str_;
+  basic_format_parse_context<Char> parse_context_;
+
+ public:
+  FMT_CONSTEXPR format_string_compiler(basic_string_view<Char> format_str,
+                                       PartHandler handler)
+      : handler_(handler),
+        format_str_(format_str),
+        parse_context_(format_str) {}
+
+  FMT_CONSTEXPR void on_text(const Char* begin, const Char* end) {
+    if (begin != end)
+      handler_(part::make_text({begin, to_unsigned(end - begin)}));
+  }
+
+  FMT_CONSTEXPR void on_arg_id() {
+    part_ = part::make_arg_index(parse_context_.next_arg_id());
+  }
+
+  FMT_CONSTEXPR void on_arg_id(int id) {
+    parse_context_.check_arg_id(id);
+    part_ = part::make_arg_index(id);
+  }
+
+  FMT_CONSTEXPR void on_arg_id(basic_string_view<Char> id) {
+    part_ = part::make_arg_name(id);
+  }
+
+  FMT_CONSTEXPR void on_replacement_field(const Char* ptr) {
+    part_.arg_id_end = ptr;
+    handler_(part_);
+  }
+
+  FMT_CONSTEXPR const Char* on_format_specs(const Char* begin,
+                                            const Char* end) {
+    auto repl = typename part::replacement();
+    dynamic_specs_handler<basic_format_parse_context<Char>> handler(
+        repl.specs, parse_context_);
+    auto it = parse_format_specs(begin, end, handler);
+    if (*it != '}') on_error("missing '}' in format string");
+    repl.arg_id = part_.part_kind == part::kind::arg_index
+                      ? arg_ref<Char>(part_.val.arg_index)
+                      : arg_ref<Char>(part_.val.str);
+    auto part = part::make_replacement(repl);
+    part.arg_id_end = begin;
+    handler_(part);
+    return it;
+  }
+};
+
+// Compiles a format string and invokes handler(part) for each parsed part.
+template <bool IS_CONSTEXPR, typename Char, typename PartHandler>
+FMT_CONSTEXPR void compile_format_string(basic_string_view<Char> format_str,
+                                         PartHandler handler) {
+  parse_format_string<IS_CONSTEXPR>(
+      format_str,
+      format_string_compiler<Char, PartHandler>(format_str, handler));
+}
+
+template <typename Range, typename Context, typename Id>
+void format_arg(
+    basic_format_parse_context<typename Range::value_type>& parse_ctx,
+    Context& ctx, Id arg_id) {
+  ctx.advance_to(
+      visit_format_arg(arg_formatter<Range>(ctx, &parse_ctx), ctx.arg(arg_id)));
+}
+
+// vformat_to is defined in a subnamespace to prevent ADL.
+namespace cf {
+template <typename Context, typename Range, typename CompiledFormat>
+auto vformat_to(Range out, CompiledFormat& cf, basic_format_args<Context> args)
+    -> typename Context::iterator {
+  using char_type = typename Context::char_type;
+  basic_format_parse_context<char_type> parse_ctx(
+      to_string_view(cf.format_str_));
+  Context ctx(out.begin(), args);
+
+  const auto& parts = cf.parts();
+  for (auto part_it = std::begin(parts); part_it != std::end(parts);
+       ++part_it) {
+    const auto& part = *part_it;
+    const auto& value = part.val;
+
+    using format_part_t = format_part<char_type>;
+    switch (part.part_kind) {
+    case format_part_t::kind::text: {
+      const auto text = value.str;
+      auto output = ctx.out();
+      auto&& it = reserve(output, text.size());
+      it = std::copy_n(text.begin(), text.size(), it);
+      ctx.advance_to(output);
+      break;
+    }
+
+    case format_part_t::kind::arg_index:
+      advance_to(parse_ctx, part.arg_id_end);
+      internal::format_arg<Range>(parse_ctx, ctx, value.arg_index);
+      break;
+
+    case format_part_t::kind::arg_name:
+      advance_to(parse_ctx, part.arg_id_end);
+      internal::format_arg<Range>(parse_ctx, ctx, value.str);
+      break;
+
+    case format_part_t::kind::replacement: {
+      const auto& arg_id_value = value.repl.arg_id.val;
+      const auto arg = value.repl.arg_id.kind == arg_id_kind::index
+                           ? ctx.arg(arg_id_value.index)
+                           : ctx.arg(arg_id_value.name);
+
+      auto specs = value.repl.specs;
+
+      handle_dynamic_spec<width_checker>(specs.width, specs.width_ref, ctx);
+      handle_dynamic_spec<precision_checker>(specs.precision,
+                                             specs.precision_ref, ctx);
+
+      error_handler h;
+      numeric_specs_checker<error_handler> checker(h, arg.type());
+      if (specs.align == align::numeric) checker.require_numeric_argument();
+      if (specs.sign != sign::none) checker.check_sign();
+      if (specs.alt) checker.require_numeric_argument();
+      if (specs.precision >= 0) checker.check_precision();
+
+      advance_to(parse_ctx, part.arg_id_end);
+      ctx.advance_to(
+          visit_format_arg(arg_formatter<Range>(ctx, nullptr, &specs), arg));
+      break;
+    }
+    }
+  }
+  return ctx.out();
+}
+}  // namespace cf
+
+struct basic_compiled_format {};
+
+template <typename S, typename = void>
+struct compiled_format_base : basic_compiled_format {
+  using char_type = char_t<S>;
+  using parts_container = std::vector<internal::format_part<char_type>>;
+
+  parts_container compiled_parts;
+
+  explicit compiled_format_base(basic_string_view<char_type> format_str) {
+    compile_format_string<false>(format_str,
+                                 [this](const format_part<char_type>& part) {
+                                   compiled_parts.push_back(part);
+                                 });
+  }
+
+  const parts_container& parts() const { return compiled_parts; }
+};
+
+template <typename Char, unsigned N> struct format_part_array {
+  format_part<Char> data[N] = {};
+  FMT_CONSTEXPR format_part_array() = default;
+};
+
+template <typename Char, unsigned N>
+FMT_CONSTEXPR format_part_array<Char, N> compile_to_parts(
+    basic_string_view<Char> format_str) {
+  format_part_array<Char, N> parts;
+  unsigned counter = 0;
+  // This is not a lambda for compatibility with older compilers.
+  struct {
+    format_part<Char>* parts;
+    unsigned* counter;
+    FMT_CONSTEXPR void operator()(const format_part<Char>& part) {
+      parts[(*counter)++] = part;
+    }
+  } collector{parts.data, &counter};
+  compile_format_string<true>(format_str, collector);
+  if (counter < N) {
+    parts.data[counter] =
+        format_part<Char>::make_text(basic_string_view<Char>());
+  }
+  return parts;
+}
+
+template <typename T> constexpr const T& constexpr_max(const T& a, const T& b) {
+  return (a < b) ? b : a;
+}
+
+template <typename S>
+struct compiled_format_base<S, enable_if_t<is_compile_string<S>::value>>
+    : basic_compiled_format {
+  using char_type = char_t<S>;
+
+  FMT_CONSTEXPR explicit compiled_format_base(basic_string_view<char_type>) {}
+
+// Workaround for old compilers. Format string compilation will not be
+// performed there anyway.
+#if FMT_USE_CONSTEXPR
+  static FMT_CONSTEXPR_DECL const unsigned num_format_parts =
+      constexpr_max(count_parts(to_string_view(S())), 1u);
+#else
+  static const unsigned num_format_parts = 1;
+#endif
+
+  using parts_container = format_part<char_type>[num_format_parts];
+
+  const parts_container& parts() const {
+    static FMT_CONSTEXPR_DECL const auto compiled_parts =
+        compile_to_parts<char_type, num_format_parts>(
+            internal::to_string_view(S()));
+    return compiled_parts.data;
+  }
+};
+
+template <typename S, typename... Args>
+class compiled_format : private compiled_format_base<S> {
+ public:
+  using typename compiled_format_base<S>::char_type;
+
+ private:
+  basic_string_view<char_type> format_str_;
+
+  template <typename Context, typename Range, typename CompiledFormat>
+  friend auto cf::vformat_to(Range out, CompiledFormat& cf,
+                             basic_format_args<Context> args) ->
+      typename Context::iterator;
+
+ public:
+  compiled_format() = delete;
+  explicit constexpr compiled_format(basic_string_view<char_type> format_str)
+      : compiled_format_base<S>(format_str), format_str_(format_str) {}
+};
+
+#ifdef __cpp_if_constexpr
+template <typename... Args> struct type_list {};
+
+// Returns a reference to the argument at index N from [first, rest...].
+template <int N, typename T, typename... Args>
+constexpr const auto& get(const T& first, const Args&... rest) {
+  static_assert(N < 1 + sizeof...(Args), "index is out of bounds");
+  if constexpr (N == 0)
+    return first;
+  else
+    return get<N - 1>(rest...);
+}
+
+template <int N, typename> struct get_type_impl;
+
+template <int N, typename... Args> struct get_type_impl<N, type_list<Args...>> {
+  using type = remove_cvref_t<decltype(get<N>(std::declval<Args>()...))>;
+};
+
+template <int N, typename T>
+using get_type = typename get_type_impl<N, T>::type;
+
+template <typename T> struct is_compiled_format : std::false_type {};
+
+template <typename Char> struct text {
+  basic_string_view<Char> data;
+  using char_type = Char;
+
+  template <typename OutputIt, typename... Args>
+  OutputIt format(OutputIt out, const Args&...) const {
+    // TODO: reserve
+    return copy_str<Char>(data.begin(), data.end(), out);
+  }
+};
+
+template <typename Char>
+struct is_compiled_format<text<Char>> : std::true_type {};
+
+template <typename Char>
+constexpr text<Char> make_text(basic_string_view<Char> s, size_t pos,
+                               size_t size) {
+  return {{&s[pos], size}};
+}
+
+template <typename Char, typename OutputIt, typename T,
+          std::enable_if_t<std::is_integral_v<T>, int> = 0>
+OutputIt format_default(OutputIt out, T value) {
+  // TODO: reserve
+  format_int fi(value);
+  return std::copy(fi.data(), fi.data() + fi.size(), out);
+}
+
+template <typename Char, typename OutputIt>
+OutputIt format_default(OutputIt out, double value) {
+  writer w(out);
+  w.write(value);
+  return w.out();
+}
+
+template <typename Char, typename OutputIt>
+OutputIt format_default(OutputIt out, Char value) {
+  *out++ = value;
+  return out;
+}
+
+template <typename Char, typename OutputIt>
+OutputIt format_default(OutputIt out, const Char* value) {
+  auto length = std::char_traits<Char>::length(value);
+  return copy_str<Char>(value, value + length, out);
+}
+
+// A replacement field that refers to argument N.
+template <typename Char, typename T, int N> struct field {
+  using char_type = Char;
+
+  template <typename OutputIt, typename... Args>
+  OutputIt format(OutputIt out, const Args&... args) const {
+    // This ensures that the argument type is convertile to `const T&`.
+    const T& arg = get<N>(args...);
+    return format_default<Char>(out, arg);
+  }
+};
+
+template <typename Char, typename T, int N>
+struct is_compiled_format<field<Char, T, N>> : std::true_type {};
+
+template <typename L, typename R> struct concat {
+  L lhs;
+  R rhs;
+  using char_type = typename L::char_type;
+
+  template <typename OutputIt, typename... Args>
+  OutputIt format(OutputIt out, const Args&... args) const {
+    out = lhs.format(out, args...);
+    return rhs.format(out, args...);
+  }
+};
+
+template <typename L, typename R>
+struct is_compiled_format<concat<L, R>> : std::true_type {};
+
+template <typename L, typename R>
+constexpr concat<L, R> make_concat(L lhs, R rhs) {
+  return {lhs, rhs};
+}
+
+struct unknown_format {};
+
+template <typename Char>
+constexpr size_t parse_text(basic_string_view<Char> str, size_t pos) {
+  for (size_t size = str.size(); pos != size; ++pos) {
+    if (str[pos] == '{' || str[pos] == '}') break;
+  }
+  return pos;
+}
+
+template <typename Args, size_t POS, int ID, typename S>
+constexpr auto compile_format_string(S format_str);
+
+template <typename Args, size_t POS, int ID, typename T, typename S>
+constexpr auto parse_tail(T head, S format_str) {
+  if constexpr (POS != to_string_view(format_str).size()) {
+    constexpr auto tail = compile_format_string<Args, POS, ID>(format_str);
+    if constexpr (std::is_same<remove_cvref_t<decltype(tail)>,
+                               unknown_format>())
+      return tail;
+    else
+      return make_concat(head, tail);
+  } else {
+    return head;
+  }
+}
+
+// Compiles a non-empty format string and returns the compiled representation
+// or unknown_format() on unrecognized input.
+template <typename Args, size_t POS, int ID, typename S>
+constexpr auto compile_format_string(S format_str) {
+  using char_type = typename S::char_type;
+  constexpr basic_string_view<char_type> str = format_str;
+  if constexpr (str[POS] == '{') {
+    if (POS + 1 == str.size())
+      throw format_error("unmatched '{' in format string");
+    if constexpr (str[POS + 1] == '{') {
+      return parse_tail<Args, POS + 2, ID>(make_text(str, POS, 1), format_str);
+    } else if constexpr (str[POS + 1] == '}') {
+      using type = get_type<ID, Args>;
+      if constexpr (std::is_same<type, int>::value) {
+        return parse_tail<Args, POS + 2, ID + 1>(field<char_type, type, ID>(),
+                                                 format_str);
+      } else {
+        return unknown_format();
+      }
+    } else {
+      return unknown_format();
+    }
+  } else if constexpr (str[POS] == '}') {
+    if (POS + 1 == str.size())
+      throw format_error("unmatched '}' in format string");
+    return parse_tail<Args, POS + 2, ID>(make_text(str, POS, 1), format_str);
+  } else {
+    constexpr auto end = parse_text(str, POS + 1);
+    return parse_tail<Args, end, ID>(make_text(str, POS, end - POS),
+                                     format_str);
+  }
+}
+#endif  // __cpp_if_constexpr
+}  // namespace internal
+
+#if FMT_USE_CONSTEXPR
+#  ifdef __cpp_if_constexpr
+template <typename... Args, typename S,
+          FMT_ENABLE_IF(is_compile_string<S>::value)>
+constexpr auto compile(S format_str) {
+  constexpr basic_string_view<typename S::char_type> str = format_str;
+  if constexpr (str.size() == 0) {
+    return internal::make_text(str, 0, 0);
+  } else {
+    constexpr auto result =
+        internal::compile_format_string<internal::type_list<Args...>, 0, 0>(
+            format_str);
+    if constexpr (std::is_same<remove_cvref_t<decltype(result)>,
+                               internal::unknown_format>()) {
+      return internal::compiled_format<S, Args...>(to_string_view(format_str));
+    } else {
+      return result;
+    }
+  }
+}
+
+template <typename CompiledFormat, typename... Args,
+          typename Char = typename CompiledFormat::char_type,
+          FMT_ENABLE_IF(internal::is_compiled_format<CompiledFormat>::value)>
+std::basic_string<Char> format(const CompiledFormat& cf, const Args&... args) {
+  basic_memory_buffer<Char> buffer;
+  cf.format(std::back_inserter(buffer), args...);
+  return to_string(buffer);
+}
+
+template <typename OutputIt, typename CompiledFormat, typename... Args,
+          FMT_ENABLE_IF(internal::is_compiled_format<CompiledFormat>::value)>
+OutputIt format_to(OutputIt out, const CompiledFormat& cf,
+                   const Args&... args) {
+  return cf.format(out, args...);
+}
+#  else
+template <typename... Args, typename S,
+          FMT_ENABLE_IF(is_compile_string<S>::value)>
+constexpr auto compile(S format_str) -> internal::compiled_format<S, Args...> {
+  return internal::compiled_format<S, Args...>(to_string_view(format_str));
+}
+#  endif  // __cpp_if_constexpr
+#endif    // FMT_USE_CONSTEXPR
+
+// Compiles the format string which must be a string literal.
+template <typename... Args, typename Char, size_t N>
+auto compile(const Char (&format_str)[N])
+    -> internal::compiled_format<const Char*, Args...> {
+  return internal::compiled_format<const Char*, Args...>(
+      basic_string_view<Char>(format_str, N - 1));
+}
+
+template <typename CompiledFormat, typename... Args,
+          typename Char = typename CompiledFormat::char_type,
+          FMT_ENABLE_IF(std::is_base_of<internal::basic_compiled_format,
+                                        CompiledFormat>::value)>
+std::basic_string<Char> format(const CompiledFormat& cf, const Args&... args) {
+  basic_memory_buffer<Char> buffer;
+  using range = buffer_range<Char>;
+  using context = buffer_context<Char>;
+  internal::cf::vformat_to<context>(range(buffer), cf,
+                                    make_format_args<context>(args...));
+  return to_string(buffer);
+}
+
+template <typename OutputIt, typename CompiledFormat, typename... Args,
+          FMT_ENABLE_IF(std::is_base_of<internal::basic_compiled_format,
+                                        CompiledFormat>::value)>
+OutputIt format_to(OutputIt out, const CompiledFormat& cf,
+                   const Args&... args) {
+  using char_type = typename CompiledFormat::char_type;
+  using range = internal::output_range<OutputIt, char_type>;
+  using context = format_context_t<OutputIt, char_type>;
+  return internal::cf::vformat_to<context>(range(out), cf,
+                                           make_format_args<context>(args...));
+}
+
+template <typename OutputIt, typename CompiledFormat, typename... Args,
+          FMT_ENABLE_IF(internal::is_output_iterator<OutputIt>::value)>
+format_to_n_result<OutputIt> format_to_n(OutputIt out, size_t n,
+                                         const CompiledFormat& cf,
+                                         const Args&... args) {
+  auto it =
+      format_to(internal::truncating_iterator<OutputIt>(out, n), cf, args...);
+  return {it.base(), it.count()};
+}
+
+template <typename CompiledFormat, typename... Args>
+std::size_t formatted_size(const CompiledFormat& cf, const Args&... args) {
+  return format_to(internal::counting_iterator(), cf, args...).count();
+}
+
+FMT_END_NAMESPACE
+
+#endif  // FMT_COMPILE_H_
--- a/src/spdlog/fmt/bundled/core.h
+++ b/src/spdlog/fmt/bundled/core.h
--- a/src/spdlog/fmt/bundled/format-inl.h
+++ b/src/spdlog/fmt/bundled/format-inl.h
--- a/src/spdlog/fmt/bundled/format.h
+++ b/src/spdlog/fmt/bundled/format.h
--- a/src/spdlog/fmt/bundled/locale.h
+++ b/src/spdlog/fmt/bundled/locale.h
@@ -0,0 +1,78 @@
+// Formatting library for C++ - std::locale support
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_LOCALE_H_
+#define FMT_LOCALE_H_
+
+#include <locale>
+
+#include "format.h"
+
+FMT_BEGIN_NAMESPACE
+
+namespace internal {
+template <typename Char>
+typename buffer_context<Char>::iterator vformat_to(
+    const std::locale& loc, buffer<Char>& buf,
+    basic_string_view<Char> format_str,
+    basic_format_args<buffer_context<type_identity_t<Char>>> args) {
+  using range = buffer_range<Char>;
+  return vformat_to<arg_formatter<range>>(buf, to_string_view(format_str), args,
+                                          internal::locale_ref(loc));
+}
+
+template <typename Char>
+std::basic_string<Char> vformat(
+    const std::locale& loc, basic_string_view<Char> format_str,
+    basic_format_args<buffer_context<type_identity_t<Char>>> args) {
+  basic_memory_buffer<Char> buffer;
+  internal::vformat_to(loc, buffer, format_str, args);
+  return fmt::to_string(buffer);
+}
+}  // namespace internal
+
+template <typename S, typename Char = char_t<S>>
+inline std::basic_string<Char> vformat(
+    const std::locale& loc, const S& format_str,
+    basic_format_args<buffer_context<type_identity_t<Char>>> args) {
+  return internal::vformat(loc, to_string_view(format_str), args);
+}
+
+template <typename S, typename... Args, typename Char = char_t<S>>
+inline std::basic_string<Char> format(const std::locale& loc,
+                                      const S& format_str, Args&&... args) {
+  return internal::vformat(
+      loc, to_string_view(format_str),
+      internal::make_args_checked<Args...>(format_str, args...));
+}
+
+template <typename S, typename OutputIt, typename... Args,
+          typename Char = enable_if_t<
+              internal::is_output_iterator<OutputIt>::value, char_t<S>>>
+inline OutputIt vformat_to(
+    OutputIt out, const std::locale& loc, const S& format_str,
+    format_args_t<type_identity_t<OutputIt>, Char> args) {
+  using range = internal::output_range<OutputIt, Char>;
+  return vformat_to<arg_formatter<range>>(
+      range(out), to_string_view(format_str), args, internal::locale_ref(loc));
+}
+
+template <typename OutputIt, typename S, typename... Args,
+          FMT_ENABLE_IF(internal::is_output_iterator<OutputIt>::value&&
+                            internal::is_string<S>::value)>
+inline OutputIt format_to(OutputIt out, const std::locale& loc,
+                          const S& format_str, Args&&... args) {
+  internal::check_format_string<Args...>(format_str);
+  using context = format_context_t<OutputIt, char_t<S>>;
+  format_arg_store<context, Args...> as{args...};
+  return vformat_to(out, loc, to_string_view(format_str),
+                    basic_format_args<context>(as));
+}
+
+FMT_END_NAMESPACE
+
+#endif  // FMT_LOCALE_H_
--- a/src/spdlog/fmt/bundled/ostream.h
+++ b/src/spdlog/fmt/bundled/ostream.h
@@ -0,0 +1,166 @@
+// Formatting library for C++ - std::ostream support
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_OSTREAM_H_
+#define FMT_OSTREAM_H_
+
+#include <ostream>
+
+#include "format.h"
+
+FMT_BEGIN_NAMESPACE
+
+template <typename CHar> class basic_printf_parse_context;
+template <typename OutputIt, typename Char> class basic_printf_context;
+
+namespace internal {
+
+template <class Char> class formatbuf : public std::basic_streambuf<Char> {
+ private:
+  using int_type = typename std::basic_streambuf<Char>::int_type;
+  using traits_type = typename std::basic_streambuf<Char>::traits_type;
+
+  buffer<Char>& buffer_;
+
+ public:
+  formatbuf(buffer<Char>& buf) : buffer_(buf) {}
+
+ protected:
+  // The put-area is actually always empty. This makes the implementation
+  // simpler and has the advantage that the streambuf and the buffer are always
+  // in sync and sputc never writes into uninitialized memory. The obvious
+  // disadvantage is that each call to sputc always results in a (virtual) call
+  // to overflow. There is no disadvantage here for sputn since this always
+  // results in a call to xsputn.
+
+  int_type overflow(int_type ch = traits_type::eof()) FMT_OVERRIDE {
+    if (!traits_type::eq_int_type(ch, traits_type::eof()))
+      buffer_.push_back(static_cast<Char>(ch));
+    return ch;
+  }
+
+  std::streamsize xsputn(const Char* s, std::streamsize count) FMT_OVERRIDE {
+    buffer_.append(s, s + count);
+    return count;
+  }
+};
+
+template <typename Char> struct test_stream : std::basic_ostream<Char> {
+ private:
+  // Hide all operator<< from std::basic_ostream<Char>.
+  void_t<> operator<<(null<>);
+  void_t<> operator<<(const Char*);
+
+  template <typename T, FMT_ENABLE_IF(std::is_convertible<T, int>::value &&
+                                      !std::is_enum<T>::value)>
+  void_t<> operator<<(T);
+};
+
+// Checks if T has a user-defined operator<< (e.g. not a member of
+// std::ostream).
+template <typename T, typename Char> class is_streamable {
+ private:
+  template <typename U>
+  static bool_constant<!std::is_same<decltype(std::declval<test_stream<Char>&>()
+                                              << std::declval<U>()),
+                                     void_t<>>::value>
+  test(int);
+
+  template <typename> static std::false_type test(...);
+
+  using result = decltype(test<T>(0));
+
+ public:
+  static const bool value = result::value;
+};
+
+// Write the content of buf to os.
+template <typename Char>
+void write(std::basic_ostream<Char>& os, buffer<Char>& buf) {
+  const Char* buf_data = buf.data();
+  using unsigned_streamsize = std::make_unsigned<std::streamsize>::type;
+  unsigned_streamsize size = buf.size();
+  unsigned_streamsize max_size = to_unsigned(max_value<std::streamsize>());
+  do {
+    unsigned_streamsize n = size <= max_size ? size : max_size;
+    os.write(buf_data, static_cast<std::streamsize>(n));
+    buf_data += n;
+    size -= n;
+  } while (size != 0);
+}
+
+template <typename Char, typename T>
+void format_value(buffer<Char>& buf, const T& value,
+                  locale_ref loc = locale_ref()) {
+  formatbuf<Char> format_buf(buf);
+  std::basic_ostream<Char> output(&format_buf);
+#if !defined(FMT_STATIC_THOUSANDS_SEPARATOR)
+  if (loc) output.imbue(loc.get<std::locale>());
+#endif
+  output.exceptions(std::ios_base::failbit | std::ios_base::badbit);
+  output << value;
+  buf.resize(buf.size());
+}
+
+// Formats an object of type T that has an overloaded ostream operator<<.
+template <typename T, typename Char>
+struct fallback_formatter<T, Char, enable_if_t<is_streamable<T, Char>::value>>
+    : private formatter<basic_string_view<Char>, Char> {
+  auto parse(basic_format_parse_context<Char>& ctx) -> decltype(ctx.begin()) {
+    return formatter<basic_string_view<Char>, Char>::parse(ctx);
+  }
+  template <typename ParseCtx,
+            FMT_ENABLE_IF(std::is_same<
+                          ParseCtx, basic_printf_parse_context<Char>>::value)>
+  auto parse(ParseCtx& ctx) -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+
+  template <typename OutputIt>
+  auto format(const T& value, basic_format_context<OutputIt, Char>& ctx)
+      -> OutputIt {
+    basic_memory_buffer<Char> buffer;
+    format_value(buffer, value, ctx.locale());
+    basic_string_view<Char> str(buffer.data(), buffer.size());
+    return formatter<basic_string_view<Char>, Char>::format(str, ctx);
+  }
+  template <typename OutputIt>
+  auto format(const T& value, basic_printf_context<OutputIt, Char>& ctx)
+      -> OutputIt {
+    basic_memory_buffer<Char> buffer;
+    format_value(buffer, value, ctx.locale());
+    return std::copy(buffer.begin(), buffer.end(), ctx.out());
+  }
+};
+}  // namespace internal
+
+template <typename Char>
+void vprint(std::basic_ostream<Char>& os, basic_string_view<Char> format_str,
+            basic_format_args<buffer_context<type_identity_t<Char>>> args) {
+  basic_memory_buffer<Char> buffer;
+  internal::vformat_to(buffer, format_str, args);
+  internal::write(os, buffer);
+}
+
+/**
+  \rst
+  Prints formatted data to the stream *os*.
+
+  **Example**::
+
+    fmt::print(cerr, "Don't {}!", "panic");
+  \endrst
+ */
+template <typename S, typename... Args,
+          typename Char = enable_if_t<internal::is_string<S>::value, char_t<S>>>
+void print(std::basic_ostream<Char>& os, const S& format_str, Args&&... args) {
+  vprint(os, to_string_view(format_str),
+         internal::make_args_checked<Args...>(format_str, args...));
+}
+FMT_END_NAMESPACE
+
+#endif  // FMT_OSTREAM_H_
--- a/src/spdlog/fmt/bundled/posix.h
+++ b/src/spdlog/fmt/bundled/posix.h
@@ -0,0 +1,2 @@
+#include "os.h"
+#warning "fmt/posix.h is deprecated; use fmt/os.h instead"
--- a/src/spdlog/fmt/bundled/printf.h
+++ b/src/spdlog/fmt/bundled/printf.h
@@ -0,0 +1,726 @@
+// Formatting library for C++ - legacy printf implementation
+//
+// Copyright (c) 2012 - 2016, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_PRINTF_H_
+#define FMT_PRINTF_H_
+
+#include <algorithm>  // std::max
+#include <limits>     // std::numeric_limits
+
+#include "ostream.h"
+
+FMT_BEGIN_NAMESPACE
+namespace internal {
+
+// Checks if a value fits in int - used to avoid warnings about comparing
+// signed and unsigned integers.
+template <bool IsSigned> struct int_checker {
+  template <typename T> static bool fits_in_int(T value) {
+    unsigned max = max_value<int>();
+    return value <= max;
+  }
+  static bool fits_in_int(bool) { return true; }
+};
+
+template <> struct int_checker<true> {
+  template <typename T> static bool fits_in_int(T value) {
+    return value >= (std::numeric_limits<int>::min)() &&
+           value <= max_value<int>();
+  }
+  static bool fits_in_int(int) { return true; }
+};
+
+class printf_precision_handler {
+ public:
+  template <typename T, FMT_ENABLE_IF(std::is_integral<T>::value)>
+  int operator()(T value) {
+    if (!int_checker<std::numeric_limits<T>::is_signed>::fits_in_int(value))
+      FMT_THROW(format_error("number is too big"));
+    return (std::max)(static_cast<int>(value), 0);
+  }
+
+  template <typename T, FMT_ENABLE_IF(!std::is_integral<T>::value)>
+  int operator()(T) {
+    FMT_THROW(format_error("precision is not integer"));
+    return 0;
+  }
+};
+
+// An argument visitor that returns true iff arg is a zero integer.
+class is_zero_int {
+ public:
+  template <typename T, FMT_ENABLE_IF(std::is_integral<T>::value)>
+  bool operator()(T value) {
+    return value == 0;
+  }
+
+  template <typename T, FMT_ENABLE_IF(!std::is_integral<T>::value)>
+  bool operator()(T) {
+    return false;
+  }
+};
+
+template <typename T> struct make_unsigned_or_bool : std::make_unsigned<T> {};
+
+template <> struct make_unsigned_or_bool<bool> { using type = bool; };
+
+template <typename T, typename Context> class arg_converter {
+ private:
+  using char_type = typename Context::char_type;
+
+  basic_format_arg<Context>& arg_;
+  char_type type_;
+
+ public:
+  arg_converter(basic_format_arg<Context>& arg, char_type type)
+      : arg_(arg), type_(type) {}
+
+  void operator()(bool value) {
+    if (type_ != 's') operator()<bool>(value);
+  }
+
+  template <typename U, FMT_ENABLE_IF(std::is_integral<U>::value)>
+  void operator()(U value) {
+    bool is_signed = type_ == 'd' || type_ == 'i';
+    using target_type = conditional_t<std::is_same<T, void>::value, U, T>;
+    if (const_check(sizeof(target_type) <= sizeof(int))) {
+      // Extra casts are used to silence warnings.
+      if (is_signed) {
+        arg_ = internal::make_arg<Context>(
+            static_cast<int>(static_cast<target_type>(value)));
+      } else {
+        using unsigned_type = typename make_unsigned_or_bool<target_type>::type;
+        arg_ = internal::make_arg<Context>(
+            static_cast<unsigned>(static_cast<unsigned_type>(value)));
+      }
+    } else {
+      if (is_signed) {
+        // glibc's printf doesn't sign extend arguments of smaller types:
+        //   std::printf("%lld", -42);  // prints "4294967254"
+        // but we don't have to do the same because it's a UB.
+        arg_ = internal::make_arg<Context>(static_cast<long long>(value));
+      } else {
+        arg_ = internal::make_arg<Context>(
+            static_cast<typename make_unsigned_or_bool<U>::type>(value));
+      }
+    }
+  }
+
+  template <typename U, FMT_ENABLE_IF(!std::is_integral<U>::value)>
+  void operator()(U) {}  // No conversion needed for non-integral types.
+};
+
+// Converts an integer argument to T for printf, if T is an integral type.
+// If T is void, the argument is converted to corresponding signed or unsigned
+// type depending on the type specifier: 'd' and 'i' - signed, other -
+// unsigned).
+template <typename T, typename Context, typename Char>
+void convert_arg(basic_format_arg<Context>& arg, Char type) {
+  visit_format_arg(arg_converter<T, Context>(arg, type), arg);
+}
+
+// Converts an integer argument to char for printf.
+template <typename Context> class char_converter {
+ private:
+  basic_format_arg<Context>& arg_;
+
+ public:
+  explicit char_converter(basic_format_arg<Context>& arg) : arg_(arg) {}
+
+  template <typename T, FMT_ENABLE_IF(std::is_integral<T>::value)>
+  void operator()(T value) {
+    arg_ = internal::make_arg<Context>(
+        static_cast<typename Context::char_type>(value));
+  }
+
+  template <typename T, FMT_ENABLE_IF(!std::is_integral<T>::value)>
+  void operator()(T) {}  // No conversion needed for non-integral types.
+};
+
+// Checks if an argument is a valid printf width specifier and sets
+// left alignment if it is negative.
+template <typename Char> class printf_width_handler {
+ private:
+  using format_specs = basic_format_specs<Char>;
+
+  format_specs& specs_;
+
+ public:
+  explicit printf_width_handler(format_specs& specs) : specs_(specs) {}
+
+  template <typename T, FMT_ENABLE_IF(std::is_integral<T>::value)>
+  unsigned operator()(T value) {
+    auto width = static_cast<uint32_or_64_or_128_t<T>>(value);
+    if (internal::is_negative(value)) {
+      specs_.align = align::left;
+      width = 0 - width;
+    }
+    unsigned int_max = max_value<int>();
+    if (width > int_max) FMT_THROW(format_error("number is too big"));
+    return static_cast<unsigned>(width);
+  }
+
+  template <typename T, FMT_ENABLE_IF(!std::is_integral<T>::value)>
+  unsigned operator()(T) {
+    FMT_THROW(format_error("width is not integer"));
+    return 0;
+  }
+};
+
+template <typename Char, typename Context>
+void printf(buffer<Char>& buf, basic_string_view<Char> format,
+            basic_format_args<Context> args) {
+  Context(std::back_inserter(buf), format, args).format();
+}
+
+template <typename OutputIt, typename Char, typename Context>
+internal::truncating_iterator<OutputIt> printf(
+    internal::truncating_iterator<OutputIt> it, basic_string_view<Char> format,
+    basic_format_args<Context> args) {
+  return Context(it, format, args).format();
+}
+}  // namespace internal
+
+using internal::printf;  // For printing into memory_buffer.
+
+template <typename Range> class printf_arg_formatter;
+
+template <typename Char>
+class basic_printf_parse_context : public basic_format_parse_context<Char> {
+  using basic_format_parse_context<Char>::basic_format_parse_context;
+};
+template <typename OutputIt, typename Char> class basic_printf_context;
+
+/**
+  \rst
+  The ``printf`` argument formatter.
+  \endrst
+ */
+template <typename Range>
+class printf_arg_formatter : public internal::arg_formatter_base<Range> {
+ public:
+  using iterator = typename Range::iterator;
+
+ private:
+  using char_type = typename Range::value_type;
+  using base = internal::arg_formatter_base<Range>;
+  using context_type = basic_printf_context<iterator, char_type>;
+
+  context_type& context_;
+
+  void write_null_pointer(char) {
+    this->specs()->type = 0;
+    this->write("(nil)");
+  }
+
+  void write_null_pointer(wchar_t) {
+    this->specs()->type = 0;
+    this->write(L"(nil)");
+  }
+
+ public:
+  using format_specs = typename base::format_specs;
+
+  /**
+    \rst
+    Constructs an argument formatter object.
+    *buffer* is a reference to the output buffer and *specs* contains format
+    specifier information for standard argument types.
+    \endrst
+   */
+  printf_arg_formatter(iterator iter, format_specs& specs, context_type& ctx)
+      : base(Range(iter), &specs, internal::locale_ref()), context_(ctx) {}
+
+  template <typename T, FMT_ENABLE_IF(fmt::internal::is_integral<T>::value)>
+  iterator operator()(T value) {
+    // MSVC2013 fails to compile separate overloads for bool and char_type so
+    // use std::is_same instead.
+    if (std::is_same<T, bool>::value) {
+      format_specs& fmt_specs = *this->specs();
+      if (fmt_specs.type != 's') return base::operator()(value ? 1 : 0);
+      fmt_specs.type = 0;
+      this->write(value != 0);
+    } else if (std::is_same<T, char_type>::value) {
+      format_specs& fmt_specs = *this->specs();
+      if (fmt_specs.type && fmt_specs.type != 'c')
+        return (*this)(static_cast<int>(value));
+      fmt_specs.sign = sign::none;
+      fmt_specs.alt = false;
+      fmt_specs.align = align::right;
+      return base::operator()(value);
+    } else {
+      return base::operator()(value);
+    }
+    return this->out();
+  }
+
+  template <typename T, FMT_ENABLE_IF(std::is_floating_point<T>::value)>
+  iterator operator()(T value) {
+    return base::operator()(value);
+  }
+
+  /** Formats a null-terminated C string. */
+  iterator operator()(const char* value) {
+    if (value)
+      base::operator()(value);
+    else if (this->specs()->type == 'p')
+      write_null_pointer(char_type());
+    else
+      this->write("(null)");
+    return this->out();
+  }
+
+  /** Formats a null-terminated wide C string. */
+  iterator operator()(const wchar_t* value) {
+    if (value)
+      base::operator()(value);
+    else if (this->specs()->type == 'p')
+      write_null_pointer(char_type());
+    else
+      this->write(L"(null)");
+    return this->out();
+  }
+
+  iterator operator()(basic_string_view<char_type> value) {
+    return base::operator()(value);
+  }
+
+  iterator operator()(monostate value) { return base::operator()(value); }
+
+  /** Formats a pointer. */
+  iterator operator()(const void* value) {
+    if (value) return base::operator()(value);
+    this->specs()->type = 0;
+    write_null_pointer(char_type());
+    return this->out();
+  }
+
+  /** Formats an argument of a custom (user-defined) type. */
+  iterator operator()(typename basic_format_arg<context_type>::handle handle) {
+    handle.format(context_.parse_context(), context_);
+    return this->out();
+  }
+};
+
+template <typename T> struct printf_formatter {
+  printf_formatter() = delete;
+
+  template <typename ParseContext>
+  auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+
+  template <typename FormatContext>
+  auto format(const T& value, FormatContext& ctx) -> decltype(ctx.out()) {
+    internal::format_value(internal::get_container(ctx.out()), value);
+    return ctx.out();
+  }
+};
+
+/** This template formats data and writes the output to a writer. */
+template <typename OutputIt, typename Char> class basic_printf_context {
+ public:
+  /** The character type for the output. */
+  using char_type = Char;
+  using iterator = OutputIt;
+  using format_arg = basic_format_arg<basic_printf_context>;
+  using parse_context_type = basic_printf_parse_context<Char>;
+  template <typename T> using formatter_type = printf_formatter<T>;
+
+ private:
+  using format_specs = basic_format_specs<char_type>;
+
+  OutputIt out_;
+  basic_format_args<basic_printf_context> args_;
+  parse_context_type parse_ctx_;
+
+  static void parse_flags(format_specs& specs, const Char*& it,
+                          const Char* end);
+
+  // Returns the argument with specified index or, if arg_index is -1, the next
+  // argument.
+  format_arg get_arg(int arg_index = -1);
+
+  // Parses argument index, flags and width and returns the argument index.
+  int parse_header(const Char*& it, const Char* end, format_specs& specs);
+
+ public:
+  /**
+   \rst
+   Constructs a ``printf_context`` object. References to the arguments and
+   the writer are stored in the context object so make sure they have
+   appropriate lifetimes.
+   \endrst
+   */
+  basic_printf_context(OutputIt out, basic_string_view<char_type> format_str,
+                       basic_format_args<basic_printf_context> args)
+      : out_(out), args_(args), parse_ctx_(format_str) {}
+
+  OutputIt out() { return out_; }
+  void advance_to(OutputIt it) { out_ = it; }
+
+  internal::locale_ref locale() { return {}; }
+
+  format_arg arg(int id) const { return args_.get(id); }
+
+  parse_context_type& parse_context() { return parse_ctx_; }
+
+  FMT_CONSTEXPR void on_error(const char* message) {
+    parse_ctx_.on_error(message);
+  }
+
+  /** Formats stored arguments and writes the output to the range. */
+  template <typename ArgFormatter = printf_arg_formatter<buffer_range<Char>>>
+  OutputIt format();
+};
+
+template <typename OutputIt, typename Char>
+void basic_printf_context<OutputIt, Char>::parse_flags(format_specs& specs,
+                                                       const Char*& it,
+                                                       const Char* end) {
+  for (; it != end; ++it) {
+    switch (*it) {
+    case '-':
+      specs.align = align::left;
+      break;
+    case '+':
+      specs.sign = sign::plus;
+      break;
+    case '0':
+      specs.fill[0] = '0';
+      break;
+    case ' ':
+      specs.sign = sign::space;
+      break;
+    case '#':
+      specs.alt = true;
+      break;
+    default:
+      return;
+    }
+  }
+}
+
+template <typename OutputIt, typename Char>
+typename basic_printf_context<OutputIt, Char>::format_arg
+basic_printf_context<OutputIt, Char>::get_arg(int arg_index) {
+  if (arg_index < 0)
+    arg_index = parse_ctx_.next_arg_id();
+  else
+    parse_ctx_.check_arg_id(--arg_index);
+  return internal::get_arg(*this, arg_index);
+}
+
+template <typename OutputIt, typename Char>
+int basic_printf_context<OutputIt, Char>::parse_header(const Char*& it,
+                                                       const Char* end,
+                                                       format_specs& specs) {
+  int arg_index = -1;
+  char_type c = *it;
+  if (c >= '0' && c <= '9') {
+    // Parse an argument index (if followed by '$') or a width possibly
+    // preceded with '0' flag(s).
+    internal::error_handler eh;
+    int value = parse_nonnegative_int(it, end, eh);
+    if (it != end && *it == '$') {  // value is an argument index
+      ++it;
+      arg_index = value;
+    } else {
+      if (c == '0') specs.fill[0] = '0';
+      if (value != 0) {
+        // Nonzero value means that we parsed width and don't need to
+        // parse it or flags again, so return now.
+        specs.width = value;
+        return arg_index;
+      }
+    }
+  }
+  parse_flags(specs, it, end);
+  // Parse width.
+  if (it != end) {
+    if (*it >= '0' && *it <= '9') {
+      internal::error_handler eh;
+      specs.width = parse_nonnegative_int(it, end, eh);
+    } else if (*it == '*') {
+      ++it;
+      specs.width = static_cast<int>(visit_format_arg(
+          internal::printf_width_handler<char_type>(specs), get_arg()));
+    }
+  }
+  return arg_index;
+}
+
+template <typename OutputIt, typename Char>
+template <typename ArgFormatter>
+OutputIt basic_printf_context<OutputIt, Char>::format() {
+  auto out = this->out();
+  const Char* start = parse_ctx_.begin();
+  const Char* end = parse_ctx_.end();
+  auto it = start;
+  while (it != end) {
+    char_type c = *it++;
+    if (c != '%') continue;
+    if (it != end && *it == c) {
+      out = std::copy(start, it, out);
+      start = ++it;
+      continue;
+    }
+    out = std::copy(start, it - 1, out);
+
+    format_specs specs;
+    specs.align = align::right;
+
+    // Parse argument index, flags and width.
+    int arg_index = parse_header(it, end, specs);
+    if (arg_index == 0) on_error("argument index out of range");
+
+    // Parse precision.
+    if (it != end && *it == '.') {
+      ++it;
+      c = it != end ? *it : 0;
+      if ('0' <= c && c <= '9') {
+        internal::error_handler eh;
+        specs.precision = parse_nonnegative_int(it, end, eh);
+      } else if (c == '*') {
+        ++it;
+        specs.precision = static_cast<int>(
+            visit_format_arg(internal::printf_precision_handler(), get_arg()));
+      } else {
+        specs.precision = 0;
+      }
+    }
+
+    format_arg arg = get_arg(arg_index);
+    if (specs.alt && visit_format_arg(internal::is_zero_int(), arg))
+      specs.alt = false;
+    if (specs.fill[0] == '0') {
+      if (arg.is_arithmetic())
+        specs.align = align::numeric;
+      else
+        specs.fill[0] = ' ';  // Ignore '0' flag for non-numeric types.
+    }
+
+    // Parse length and convert the argument to the required type.
+    c = it != end ? *it++ : 0;
+    char_type t = it != end ? *it : 0;
+    using internal::convert_arg;
+    switch (c) {
+    case 'h':
+      if (t == 'h') {
+        ++it;
+        t = it != end ? *it : 0;
+        convert_arg<signed char>(arg, t);
+      } else {
+        convert_arg<short>(arg, t);
+      }
+      break;
+    case 'l':
+      if (t == 'l') {
+        ++it;
+        t = it != end ? *it : 0;
+        convert_arg<long long>(arg, t);
+      } else {
+        convert_arg<long>(arg, t);
+      }
+      break;
+    case 'j':
+      convert_arg<intmax_t>(arg, t);
+      break;
+    case 'z':
+      convert_arg<std::size_t>(arg, t);
+      break;
+    case 't':
+      convert_arg<std::ptrdiff_t>(arg, t);
+      break;
+    case 'L':
+      // printf produces garbage when 'L' is omitted for long double, no
+      // need to do the same.
+      break;
+    default:
+      --it;
+      convert_arg<void>(arg, c);
+    }
+
+    // Parse type.
+    if (it == end) FMT_THROW(format_error("invalid format string"));
+    specs.type = static_cast<char>(*it++);
+    if (arg.is_integral()) {
+      // Normalize type.
+      switch (specs.type) {
+      case 'i':
+      case 'u':
+        specs.type = 'd';
+        break;
+      case 'c':
+        visit_format_arg(internal::char_converter<basic_printf_context>(arg),
+                         arg);
+        break;
+      }
+    }
+
+    start = it;
+
+    // Format argument.
+    visit_format_arg(ArgFormatter(out, specs, *this), arg);
+  }
+  return std::copy(start, it, out);
+}
+
+template <typename Char>
+using basic_printf_context_t =
+    basic_printf_context<std::back_insert_iterator<internal::buffer<Char>>,
+                         Char>;
+
+using printf_context = basic_printf_context_t<char>;
+using wprintf_context = basic_printf_context_t<wchar_t>;
+
+using printf_args = basic_format_args<printf_context>;
+using wprintf_args = basic_format_args<wprintf_context>;
+
+/**
+  \rst
+  Constructs an `~fmt::format_arg_store` object that contains references to
+  arguments and can be implicitly converted to `~fmt::printf_args`.
+  \endrst
+ */
+template <typename... Args>
+inline format_arg_store<printf_context, Args...> make_printf_args(
+    const Args&... args) {
+  return {args...};
+}
+
+/**
+  \rst
+  Constructs an `~fmt::format_arg_store` object that contains references to
+  arguments and can be implicitly converted to `~fmt::wprintf_args`.
+  \endrst
+ */
+template <typename... Args>
+inline format_arg_store<wprintf_context, Args...> make_wprintf_args(
+    const Args&... args) {
+  return {args...};
+}
+
+template <typename S, typename Char = char_t<S>>
+inline std::basic_string<Char> vsprintf(
+    const S& format,
+    basic_format_args<basic_printf_context_t<type_identity_t<Char>>> args) {
+  basic_memory_buffer<Char> buffer;
+  printf(buffer, to_string_view(format), args);
+  return to_string(buffer);
+}
+
+/**
+  \rst
+  Formats arguments and returns the result as a string.
+
+  **Example**::
+
+    std::string message = fmt::sprintf("The answer is %d", 42);
+  \endrst
+*/
+template <typename S, typename... Args,
+          typename Char = enable_if_t<internal::is_string<S>::value, char_t<S>>>
+inline std::basic_string<Char> sprintf(const S& format, const Args&... args) {
+  using context = basic_printf_context_t<Char>;
+  return vsprintf(to_string_view(format), make_format_args<context>(args...));
+}
+
+template <typename S, typename Char = char_t<S>>
+inline int vfprintf(
+    std::FILE* f, const S& format,
+    basic_format_args<basic_printf_context_t<type_identity_t<Char>>> args) {
+  basic_memory_buffer<Char> buffer;
+  printf(buffer, to_string_view(format), args);
+  std::size_t size = buffer.size();
+  return std::fwrite(buffer.data(), sizeof(Char), size, f) < size
+             ? -1
+             : static_cast<int>(size);
+}
+
+/**
+  \rst
+  Prints formatted data to the file *f*.
+
+  **Example**::
+
+    fmt::fprintf(stderr, "Don't %s!", "panic");
+  \endrst
+ */
+template <typename S, typename... Args,
+          typename Char = enable_if_t<internal::is_string<S>::value, char_t<S>>>
+inline int fprintf(std::FILE* f, const S& format, const Args&... args) {
+  using context = basic_printf_context_t<Char>;
+  return vfprintf(f, to_string_view(format),
+                  make_format_args<context>(args...));
+}
+
+template <typename S, typename Char = char_t<S>>
+inline int vprintf(
+    const S& format,
+    basic_format_args<basic_printf_context_t<type_identity_t<Char>>> args) {
+  return vfprintf(stdout, to_string_view(format), args);
+}
+
+/**
+  \rst
+  Prints formatted data to ``stdout``.
+
+  **Example**::
+
+    fmt::printf("Elapsed time: %.2f seconds", 1.23);
+  \endrst
+ */
+template <typename S, typename... Args,
+          FMT_ENABLE_IF(internal::is_string<S>::value)>
+inline int printf(const S& format_str, const Args&... args) {
+  using context = basic_printf_context_t<char_t<S>>;
+  return vprintf(to_string_view(format_str),
+                 make_format_args<context>(args...));
+}
+
+template <typename S, typename Char = char_t<S>>
+inline int vfprintf(
+    std::basic_ostream<Char>& os, const S& format,
+    basic_format_args<basic_printf_context_t<type_identity_t<Char>>> args) {
+  basic_memory_buffer<Char> buffer;
+  printf(buffer, to_string_view(format), args);
+  internal::write(os, buffer);
+  return static_cast<int>(buffer.size());
+}
+
+/** Formats arguments and writes the output to the range. */
+template <typename ArgFormatter, typename Char,
+          typename Context =
+              basic_printf_context<typename ArgFormatter::iterator, Char>>
+typename ArgFormatter::iterator vprintf(
+    internal::buffer<Char>& out, basic_string_view<Char> format_str,
+    basic_format_args<type_identity_t<Context>> args) {
+  typename ArgFormatter::iterator iter(out);
+  Context(iter, format_str, args).template format<ArgFormatter>();
+  return iter;
+}
+
+/**
+  \rst
+  Prints formatted data to the stream *os*.
+
+  **Example**::
+
+    fmt::fprintf(cerr, "Don't %s!", "panic");
+  \endrst
+ */
+template <typename S, typename... Args, typename Char = char_t<S>>
+inline int fprintf(std::basic_ostream<Char>& os, const S& format_str,
+                   const Args&... args) {
+  using context = basic_printf_context_t<Char>;
+  return vfprintf(os, to_string_view(format_str),
+                  make_format_args<context>(args...));
+}
+FMT_END_NAMESPACE
+
+#endif  // FMT_PRINTF_H_
--- a/src/spdlog/fmt/bundled/ranges.h
+++ b/src/spdlog/fmt/bundled/ranges.h
@@ -0,0 +1,387 @@
+// Formatting library for C++ - experimental range support
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+//
+// Copyright (c) 2018 - present, Remotion (Igor Schulz)
+// All Rights Reserved
+// {fmt} support for ranges, containers and types tuple interface.
+
+#ifndef FMT_RANGES_H_
+#define FMT_RANGES_H_
+
+#include <initializer_list>
+#include <type_traits>
+
+#include "format.h"
+
+// output only up to N items from the range.
+#ifndef FMT_RANGE_OUTPUT_LENGTH_LIMIT
+#  define FMT_RANGE_OUTPUT_LENGTH_LIMIT 256
+#endif
+
+FMT_BEGIN_NAMESPACE
+
+template <typename Char> struct formatting_base {
+  template <typename ParseContext>
+  FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+};
+
+template <typename Char, typename Enable = void>
+struct formatting_range : formatting_base<Char> {
+  static FMT_CONSTEXPR_DECL const std::size_t range_length_limit =
+      FMT_RANGE_OUTPUT_LENGTH_LIMIT;  // output only up to N items from the
+                                      // range.
+  Char prefix;
+  Char delimiter;
+  Char postfix;
+  formatting_range() : prefix('{'), delimiter(','), postfix('}') {}
+  static FMT_CONSTEXPR_DECL const bool add_delimiter_spaces = true;
+  static FMT_CONSTEXPR_DECL const bool add_prepostfix_space = false;
+};
+
+template <typename Char, typename Enable = void>
+struct formatting_tuple : formatting_base<Char> {
+  Char prefix;
+  Char delimiter;
+  Char postfix;
+  formatting_tuple() : prefix('('), delimiter(','), postfix(')') {}
+  static FMT_CONSTEXPR_DECL const bool add_delimiter_spaces = true;
+  static FMT_CONSTEXPR_DECL const bool add_prepostfix_space = false;
+};
+
+namespace internal {
+
+template <typename RangeT, typename OutputIterator>
+OutputIterator copy(const RangeT& range, OutputIterator out) {
+  for (auto it = range.begin(), end = range.end(); it != end; ++it)
+    *out++ = *it;
+  return out;
+}
+
+template <typename OutputIterator>
+OutputIterator copy(const char* str, OutputIterator out) {
+  while (*str) *out++ = *str++;
+  return out;
+}
+
+template <typename OutputIterator>
+OutputIterator copy(char ch, OutputIterator out) {
+  *out++ = ch;
+  return out;
+}
+
+/// Return true value if T has std::string interface, like std::string_view.
+template <typename T> class is_like_std_string {
+  template <typename U>
+  static auto check(U* p)
+      -> decltype((void)p->find('a'), p->length(), (void)p->data(), int());
+  template <typename> static void check(...);
+
+ public:
+  static FMT_CONSTEXPR_DECL const bool value =
+      is_string<T>::value || !std::is_void<decltype(check<T>(nullptr))>::value;
+};
+
+template <typename Char>
+struct is_like_std_string<fmt::basic_string_view<Char>> : std::true_type {};
+
+template <typename... Ts> struct conditional_helper {};
+
+template <typename T, typename _ = void> struct is_range_ : std::false_type {};
+
+#if !FMT_MSC_VER || FMT_MSC_VER > 1800
+template <typename T>
+struct is_range_<
+    T, conditional_t<false,
+                     conditional_helper<decltype(std::declval<T>().begin()),
+                                        decltype(std::declval<T>().end())>,
+                     void>> : std::true_type {};
+#endif
+
+/// tuple_size and tuple_element check.
+template <typename T> class is_tuple_like_ {
+  template <typename U>
+  static auto check(U* p) -> decltype(std::tuple_size<U>::value, int());
+  template <typename> static void check(...);
+
+ public:
+  static FMT_CONSTEXPR_DECL const bool value =
+      !std::is_void<decltype(check<T>(nullptr))>::value;
+};
+
+// Check for integer_sequence
+#if defined(__cpp_lib_integer_sequence) || FMT_MSC_VER >= 1900
+template <typename T, T... N>
+using integer_sequence = std::integer_sequence<T, N...>;
+template <std::size_t... N> using index_sequence = std::index_sequence<N...>;
+template <std::size_t N>
+using make_index_sequence = std::make_index_sequence<N>;
+#else
+template <typename T, T... N> struct integer_sequence {
+  using value_type = T;
+
+  static FMT_CONSTEXPR std::size_t size() { return sizeof...(N); }
+};
+
+template <std::size_t... N>
+using index_sequence = integer_sequence<std::size_t, N...>;
+
+template <typename T, std::size_t N, T... Ns>
+struct make_integer_sequence : make_integer_sequence<T, N - 1, N - 1, Ns...> {};
+template <typename T, T... Ns>
+struct make_integer_sequence<T, 0, Ns...> : integer_sequence<T, Ns...> {};
+
+template <std::size_t N>
+using make_index_sequence = make_integer_sequence<std::size_t, N>;
+#endif
+
+template <class Tuple, class F, size_t... Is>
+void for_each(index_sequence<Is...>, Tuple&& tup, F&& f) FMT_NOEXCEPT {
+  using std::get;
+  // using free function get<I>(T) now.
+  const int _[] = {0, ((void)f(get<Is>(tup)), 0)...};
+  (void)_;  // blocks warnings
+}
+
+template <class T>
+FMT_CONSTEXPR make_index_sequence<std::tuple_size<T>::value> get_indexes(
+    T const&) {
+  return {};
+}
+
+template <class Tuple, class F> void for_each(Tuple&& tup, F&& f) {
+  const auto indexes = get_indexes(tup);
+  for_each(indexes, std::forward<Tuple>(tup), std::forward<F>(f));
+}
+
+template <typename Arg, FMT_ENABLE_IF(!is_like_std_string<
+                                      typename std::decay<Arg>::type>::value)>
+FMT_CONSTEXPR const char* format_str_quoted(bool add_space, const Arg&) {
+  return add_space ? " {}" : "{}";
+}
+
+template <typename Arg, FMT_ENABLE_IF(is_like_std_string<
+                                      typename std::decay<Arg>::type>::value)>
+FMT_CONSTEXPR const char* format_str_quoted(bool add_space, const Arg&) {
+  return add_space ? " \"{}\"" : "\"{}\"";
+}
+
+FMT_CONSTEXPR const char* format_str_quoted(bool add_space, const char*) {
+  return add_space ? " \"{}\"" : "\"{}\"";
+}
+FMT_CONSTEXPR const wchar_t* format_str_quoted(bool add_space, const wchar_t*) {
+  return add_space ? L" \"{}\"" : L"\"{}\"";
+}
+
+FMT_CONSTEXPR const char* format_str_quoted(bool add_space, const char) {
+  return add_space ? " '{}'" : "'{}'";
+}
+FMT_CONSTEXPR const wchar_t* format_str_quoted(bool add_space, const wchar_t) {
+  return add_space ? L" '{}'" : L"'{}'";
+}
+
+}  // namespace internal
+
+template <typename T> struct is_tuple_like {
+  static FMT_CONSTEXPR_DECL const bool value =
+      internal::is_tuple_like_<T>::value && !internal::is_range_<T>::value;
+};
+
+template <typename TupleT, typename Char>
+struct formatter<TupleT, Char, enable_if_t<fmt::is_tuple_like<TupleT>::value>> {
+ private:
+  // C++11 generic lambda for format()
+  template <typename FormatContext> struct format_each {
+    template <typename T> void operator()(const T& v) {
+      if (i > 0) {
+        if (formatting.add_prepostfix_space) {
+          *out++ = ' ';
+        }
+        out = internal::copy(formatting.delimiter, out);
+      }
+      out = format_to(out,
+                      internal::format_str_quoted(
+                          (formatting.add_delimiter_spaces && i > 0), v),
+                      v);
+      ++i;
+    }
+
+    formatting_tuple<Char>& formatting;
+    std::size_t& i;
+    typename std::add_lvalue_reference<decltype(
+        std::declval<FormatContext>().out())>::type out;
+  };
+
+ public:
+  formatting_tuple<Char> formatting;
+
+  template <typename ParseContext>
+  FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
+    return formatting.parse(ctx);
+  }
+
+  template <typename FormatContext = format_context>
+  auto format(const TupleT& values, FormatContext& ctx) -> decltype(ctx.out()) {
+    auto out = ctx.out();
+    std::size_t i = 0;
+    internal::copy(formatting.prefix, out);
+
+    internal::for_each(values, format_each<FormatContext>{formatting, i, out});
+    if (formatting.add_prepostfix_space) {
+      *out++ = ' ';
+    }
+    internal::copy(formatting.postfix, out);
+
+    return ctx.out();
+  }
+};
+
+template <typename T, typename Char> struct is_range {
+  static FMT_CONSTEXPR_DECL const bool value =
+      internal::is_range_<T>::value &&
+      !internal::is_like_std_string<T>::value &&
+      !std::is_convertible<T, std::basic_string<Char>>::value &&
+      !std::is_constructible<internal::std_string_view<Char>, T>::value;
+};
+
+template <typename RangeT, typename Char>
+struct formatter<RangeT, Char,
+                 enable_if_t<fmt::is_range<RangeT, Char>::value>> {
+  formatting_range<Char> formatting;
+
+  template <typename ParseContext>
+  FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
+    return formatting.parse(ctx);
+  }
+
+  template <typename FormatContext>
+  typename FormatContext::iterator format(const RangeT& values,
+                                          FormatContext& ctx) {
+    auto out = internal::copy(formatting.prefix, ctx.out());
+    std::size_t i = 0;
+    for (auto it = values.begin(), end = values.end(); it != end; ++it) {
+      if (i > 0) {
+        if (formatting.add_prepostfix_space) *out++ = ' ';
+        out = internal::copy(formatting.delimiter, out);
+      }
+      out = format_to(out,
+                      internal::format_str_quoted(
+                          (formatting.add_delimiter_spaces && i > 0), *it),
+                      *it);
+      if (++i > formatting.range_length_limit) {
+        out = format_to(out, " ... <other elements>");
+        break;
+      }
+    }
+    if (formatting.add_prepostfix_space) *out++ = ' ';
+    return internal::copy(formatting.postfix, out);
+  }
+};
+
+template <typename Char, typename... T> struct tuple_arg_join : internal::view {
+  const std::tuple<T...>& tuple;
+  basic_string_view<Char> sep;
+
+  tuple_arg_join(const std::tuple<T...>& t, basic_string_view<Char> s)
+      : tuple{t}, sep{s} {}
+};
+
+template <typename Char, typename... T>
+struct formatter<tuple_arg_join<Char, T...>, Char> {
+  template <typename ParseContext>
+  FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+
+  template <typename FormatContext>
+  typename FormatContext::iterator format(
+      const tuple_arg_join<Char, T...>& value, FormatContext& ctx) {
+    return format(value, ctx, internal::make_index_sequence<sizeof...(T)>{});
+  }
+
+ private:
+  template <typename FormatContext, size_t... N>
+  typename FormatContext::iterator format(
+      const tuple_arg_join<Char, T...>& value, FormatContext& ctx,
+      internal::index_sequence<N...>) {
+    return format_args(value, ctx, std::get<N>(value.tuple)...);
+  }
+
+  template <typename FormatContext>
+  typename FormatContext::iterator format_args(
+      const tuple_arg_join<Char, T...>&, FormatContext& ctx) {
+    // NOTE: for compilers that support C++17, this empty function instantiation
+    // can be replaced with a constexpr branch in the variadic overload.
+    return ctx.out();
+  }
+
+  template <typename FormatContext, typename Arg, typename... Args>
+  typename FormatContext::iterator format_args(
+      const tuple_arg_join<Char, T...>& value, FormatContext& ctx,
+      const Arg& arg, const Args&... args) {
+    using base = formatter<typename std::decay<Arg>::type, Char>;
+    auto out = ctx.out();
+    out = base{}.format(arg, ctx);
+    if (sizeof...(Args) > 0) {
+      out = std::copy(value.sep.begin(), value.sep.end(), out);
+      ctx.advance_to(out);
+      return format_args(value, ctx, args...);
+    }
+    return out;
+  }
+};
+
+/**
+  \rst
+  Returns an object that formats `tuple` with elements separated by `sep`.
+
+  **Example**::
+
+    std::tuple<int, char> t = {1, 'a'};
+    fmt::print("{}", fmt::join(t, ", "));
+    // Output: "1, a"
+  \endrst
+ */
+template <typename... T>
+FMT_CONSTEXPR tuple_arg_join<char, T...> join(const std::tuple<T...>& tuple,
+                                              string_view sep) {
+  return {tuple, sep};
+}
+
+template <typename... T>
+FMT_CONSTEXPR tuple_arg_join<wchar_t, T...> join(const std::tuple<T...>& tuple,
+                                                 wstring_view sep) {
+  return {tuple, sep};
+}
+
+/**
+  \rst
+  Returns an object that formats `initializer_list` with elements separated by
+  `sep`.
+
+  **Example**::
+
+    fmt::print("{}", fmt::join({1, 2, 3}, ", "));
+    // Output: "1, 2, 3"
+  \endrst
+ */
+template <typename T>
+arg_join<internal::iterator_t<const std::initializer_list<T>>, char> join(
+    std::initializer_list<T> list, string_view sep) {
+  return join(std::begin(list), std::end(list), sep);
+}
+
+template <typename T>
+arg_join<internal::iterator_t<const std::initializer_list<T>>, wchar_t> join(
+    std::initializer_list<T> list, wstring_view sep) {
+  return join(std::begin(list), std::end(list), sep);
+}
+
+FMT_END_NAMESPACE
+
+#endif  // FMT_RANGES_H_
--- a/src/spdlog/fmt/fmt.h
+++ b/src/spdlog/fmt/fmt.h
@@ -0,0 +1,25 @@
+//
+// Copyright(c) 2016-2018 Gabi Melman.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+//
+
+#pragma once
+
+//
+// Include a bundled header-only copy of fmtlib or an external one.
+// By default spdlog include its own copy.
+//
+
+#if !defined(SPDLOG_FMT_EXTERNAL)
+#if !defined(SPDLOG_COMPILED_LIB) && !defined(FMT_HEADER_ONLY)
+#define FMT_HEADER_ONLY
+#endif
+#ifndef FMT_USE_WINDOWS_H
+#define FMT_USE_WINDOWS_H 0
+#endif
+#include <spdlog/fmt/bundled/core.h>
+#include <spdlog/fmt/bundled/format.h>
+#else // SPDLOG_FMT_EXTERNAL is defined - use external fmtlib
+#include <fmt/core.h>
+#include <fmt/format.h>
+#endif
--- a/src/spdlog/fmt/ostr.h
+++ b/src/spdlog/fmt/ostr.h
@@ -0,0 +1,20 @@
+//
+// Copyright(c) 2016 Gabi Melman.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+//
+
+#pragma once
+//
+// include bundled or external copy of fmtlib's ostream support
+//
+
+#if !defined(SPDLOG_FMT_EXTERNAL)
+#ifdef SPDLOG_HEADER_ONLY
+#ifndef FMT_HEADER_ONLY
+#define FMT_HEADER_ONLY
+#endif
+#endif
+#include <spdlog/fmt/bundled/ostream.h>
+#else
+#include <fmt/ostream.h>
+#endif
--- a/src/spdlog/formatter.h
+++ b/src/spdlog/formatter.h
@@ -0,0 +1,18 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include <spdlog/fmt/fmt.h>
+#include <spdlog/details/log_msg.h>
+
+namespace spdlog {
+
+class formatter
+{
+public:
+    virtual ~formatter() = default;
+    virtual void format(const details::log_msg &msg, memory_buf_t &dest) = 0;
+    virtual std::unique_ptr<formatter> clone() const = 0;
+};
+} // namespace spdlog
--- a/src/spdlog/fwd.h
+++ b/src/spdlog/fwd.h
@@ -0,0 +1,14 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+namespace spdlog {
+class logger;
+class formatter;
+
+namespace sinks {
+class sink;
+}
+
+} // namespace spdlog
--- a/src/spdlog/logger-inl.h
+++ b/src/spdlog/logger-inl.h
@@ -0,0 +1,253 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#ifndef SPDLOG_HEADER_ONLY
+#include <spdlog/logger.h>
+#endif
+
+#include <spdlog/sinks/sink.h>
+#include <spdlog/details/backtracer.h>
+#include <spdlog/pattern_formatter.h>
+
+#include <cstdio>
+
+namespace spdlog {
+
+// public methods
+SPDLOG_INLINE logger::logger(const logger &other)
+    : name_(other.name_)
+    , sinks_(other.sinks_)
+    , level_(other.level_.load(std::memory_order_relaxed))
+    , flush_level_(other.flush_level_.load(std::memory_order_relaxed))
+    , custom_err_handler_(other.custom_err_handler_)
+    , tracer_(other.tracer_)
+{}
+
+SPDLOG_INLINE logger::logger(logger &&other) SPDLOG_NOEXCEPT : name_(std::move(other.name_)),
+                                                               sinks_(std::move(other.sinks_)),
+                                                               level_(other.level_.load(std::memory_order_relaxed)),
+                                                               flush_level_(other.flush_level_.load(std::memory_order_relaxed)),
+                                                               custom_err_handler_(std::move(other.custom_err_handler_)),
+                                                               tracer_(std::move(other.tracer_))
+
+{}
+
+SPDLOG_INLINE logger &logger::operator=(logger other) SPDLOG_NOEXCEPT
+{
+    this->swap(other);
+    return *this;
+}
+
+SPDLOG_INLINE void logger::swap(spdlog::logger &other) SPDLOG_NOEXCEPT
+{
+    name_.swap(other.name_);
+    sinks_.swap(other.sinks_);
+
+    // swap level_
+    auto other_level = other.level_.load();
+    auto my_level = level_.exchange(other_level);
+    other.level_.store(my_level);
+
+    // swap flush level_
+    other_level = other.flush_level_.load();
+    my_level = flush_level_.exchange(other_level);
+    other.flush_level_.store(my_level);
+
+    custom_err_handler_.swap(other.custom_err_handler_);
+    std::swap(tracer_, other.tracer_);
+}
+
+SPDLOG_INLINE void swap(logger &a, logger &b)
+{
+    a.swap(b);
+}
+
+SPDLOG_INLINE void logger::set_level(level::level_enum log_level)
+{
+    level_.store(log_level);
+}
+
+SPDLOG_INLINE level::level_enum logger::level() const
+{
+    return static_cast<level::level_enum>(level_.load(std::memory_order_relaxed));
+}
+
+SPDLOG_INLINE const std::string &logger::name() const
+{
+    return name_;
+}
+
+// set formatting for the sinks in this logger.
+// each sink will get a separate instance of the formatter object.
+SPDLOG_INLINE void logger::set_formatter(std::unique_ptr<formatter> f)
+{
+    for (auto it = sinks_.begin(); it != sinks_.end(); ++it)
+    {
+        if (std::next(it) == sinks_.end())
+        {
+            // last element - we can be move it.
+            (*it)->set_formatter(std::move(f));
+            break; // to prevent clang-tidy warning
+        }
+        else
+        {
+            (*it)->set_formatter(f->clone());
+        }
+    }
+}
+
+SPDLOG_INLINE void logger::set_pattern(std::string pattern, pattern_time_type time_type)
+{
+    auto new_formatter = details::make_unique<pattern_formatter>(std::move(pattern), time_type);
+    set_formatter(std::move(new_formatter));
+}
+
+// create new backtrace sink and move to it all our child sinks
+SPDLOG_INLINE void logger::enable_backtrace(size_t n_messages)
+{
+    tracer_.enable(n_messages);
+}
+
+// restore orig sinks and level and delete the backtrace sink
+SPDLOG_INLINE void logger::disable_backtrace()
+{
+    tracer_.disable();
+}
+
+SPDLOG_INLINE void logger::dump_backtrace()
+{
+    dump_backtrace_();
+}
+
+// flush functions
+SPDLOG_INLINE void logger::flush()
+{
+    flush_();
+}
+
+SPDLOG_INLINE void logger::flush_on(level::level_enum log_level)
+{
+    flush_level_.store(log_level);
+}
+
+SPDLOG_INLINE level::level_enum logger::flush_level() const
+{
+    return static_cast<level::level_enum>(flush_level_.load(std::memory_order_relaxed));
+}
+
+// sinks
+SPDLOG_INLINE const std::vector<sink_ptr> &logger::sinks() const
+{
+    return sinks_;
+}
+
+SPDLOG_INLINE std::vector<sink_ptr> &logger::sinks()
+{
+    return sinks_;
+}
+
+// error handler
+SPDLOG_INLINE void logger::set_error_handler(err_handler handler)
+{
+    custom_err_handler_ = std::move(handler);
+}
+
+// create new logger with same sinks and configuration.
+SPDLOG_INLINE std::shared_ptr<logger> logger::clone(std::string logger_name)
+{
+    auto cloned = std::make_shared<logger>(*this);
+    cloned->name_ = std::move(logger_name);
+    return cloned;
+}
+
+// protected methods
+SPDLOG_INLINE void logger::log_it_(const spdlog::details::log_msg &log_msg, bool log_enabled, bool traceback_enabled)
+{
+    if (log_enabled)
+    {
+        sink_it_(log_msg);
+    }
+    if (traceback_enabled)
+    {
+        tracer_.push_back(log_msg);
+    }
+}
+
+SPDLOG_INLINE void logger::sink_it_(const details::log_msg &msg)
+{
+    for (auto &sink : sinks_)
+    {
+        if (sink->should_log(msg.level))
+        {
+            SPDLOG_TRY
+            {
+                sink->log(msg);
+            }
+            SPDLOG_LOGGER_CATCH()
+        }
+    }
+
+    if (should_flush_(msg))
+    {
+        flush_();
+    }
+}
+
+SPDLOG_INLINE void logger::flush_()
+{
+    for (auto &sink : sinks_)
+    {
+        SPDLOG_TRY
+        {
+            sink->flush();
+        }
+        SPDLOG_LOGGER_CATCH()
+    }
+}
+
+SPDLOG_INLINE void logger::dump_backtrace_()
+{
+    using details::log_msg;
+    if (tracer_.enabled())
+    {
+        sink_it_(log_msg{name(), level::info, "****************** Backtrace Start ******************"});
+        tracer_.foreach_pop([this](const log_msg &msg) { this->sink_it_(msg); });
+        sink_it_(log_msg{name(), level::info, "****************** Backtrace End ********************"});
+    }
+}
+
+SPDLOG_INLINE bool logger::should_flush_(const details::log_msg &msg)
+{
+    auto flush_level = flush_level_.load(std::memory_order_relaxed);
+    return (msg.level >= flush_level) && (msg.level != level::off);
+}
+
+SPDLOG_INLINE void logger::err_handler_(const std::string &msg)
+{
+    if (custom_err_handler_)
+    {
+        custom_err_handler_(msg);
+    }
+    else
+    {
+        using std::chrono::system_clock;
+        static std::mutex mutex;
+        static std::chrono::system_clock::time_point last_report_time;
+        static size_t err_counter = 0;
+        std::lock_guard<std::mutex> lk{mutex};
+        auto now = system_clock::now();
+        err_counter++;
+        if (now - last_report_time < std::chrono::seconds(1))
+        {
+            return;
+        }
+        last_report_time = now;
+        auto tm_time = details::os::localtime(system_clock::to_time_t(now));
+        char date_buf[64];
+        std::strftime(date_buf, sizeof(date_buf), "%Y-%m-%d %H:%M:%S", &tm_time);
+        fprintf(stderr, "[*** LOG ERROR #%04zu ***] [%s] [%s] {%s}\n", err_counter, date_buf, name().c_str(), msg.c_str());
+    }
+}
+} // namespace spdlog
--- a/src/spdlog/logger.h
+++ b/src/spdlog/logger.h
@@ -0,0 +1,366 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+// Thread safe logger (except for set_error_handler())
+// Has name, log level, vector of std::shared sink pointers and formatter
+// Upon each log write the logger:
+// 1. Checks if its log level is enough to log the message and if yes:
+// 2. Call the underlying sinks to do the job.
+// 3. Each sink use its own private copy of a formatter to format the message
+// and send to its destination.
+//
+// The use of private formatter per sink provides the opportunity to cache some
+// formatted data, and support for different format per sink.
+
+#include <spdlog/common.h>
+#include <spdlog/details/log_msg.h>
+#include <spdlog/details/backtracer.h>
+
+#ifdef SPDLOG_WCHAR_TO_UTF8_SUPPORT
+#include <spdlog/details/os.h>
+#endif
+
+#include <vector>
+#ifndef SPDLOG_NO_EXCEPTIONS
+#define SPDLOG_LOGGER_CATCH()                                                                                                              \
+    catch (const std::exception &ex)                                                                                                       \
+    {                                                                                                                                      \
+        err_handler_(ex.what());                                                                                                           \
+    }                                                                                                                                      \
+    catch (...)                                                                                                                            \
+    {                                                                                                                                      \
+        err_handler_("Unknown exception in logger");                                                                                       \
+    }
+#else
+#define SPDLOG_LOGGER_CATCH()
+#endif
+
+namespace spdlog {
+
+class SPDLOG_API logger
+{
+public:
+    // Empty logger
+    explicit logger(std::string name)
+        : name_(std::move(name))
+        , sinks_()
+    {}
+
+    // Logger with range on sinks
+    template<typename It>
+    logger(std::string name, It begin, It end)
+        : name_(std::move(name))
+        , sinks_(begin, end)
+    {}
+
+    // Logger with single sink
+    logger(std::string name, sink_ptr single_sink)
+        : logger(std::move(name), {std::move(single_sink)})
+    {}
+
+    // Logger with sinks init list
+    logger(std::string name, sinks_init_list sinks)
+        : logger(std::move(name), sinks.begin(), sinks.end())
+    {}
+
+    virtual ~logger() = default;
+
+    logger(const logger &other);
+    logger(logger &&other) SPDLOG_NOEXCEPT;
+    logger &operator=(logger other) SPDLOG_NOEXCEPT;
+
+    void swap(spdlog::logger &other) SPDLOG_NOEXCEPT;
+
+    // FormatString is a type derived from fmt::compile_string
+    template<typename FormatString, typename std::enable_if<fmt::is_compile_string<FormatString>::value, int>::type = 0, typename... Args>
+    void log(source_loc loc, level::level_enum lvl, const FormatString &fmt, const Args &... args)
+    {
+        log_(loc, lvl, fmt, args...);
+    }
+
+    // FormatString is NOT a type derived from fmt::compile_string but is a string_view_t or can be implicitly converted to one
+    template<typename... Args>
+    void log(source_loc loc, level::level_enum lvl, string_view_t fmt, const Args &... args)
+    {
+        log_(loc, lvl, fmt, args...);
+    }
+
+    template<typename FormatString, typename... Args>
+    void log(level::level_enum lvl, const FormatString &fmt, const Args &... args)
+    {
+        log(source_loc{}, lvl, fmt, args...);
+    }
+
+    template<typename FormatString, typename... Args>
+    void trace(const FormatString &fmt, const Args &... args)
+    {
+        log(level::trace, fmt, args...);
+    }
+
+    template<typename FormatString, typename... Args>
+    void debug(const FormatString &fmt, const Args &... args)
+    {
+        log(level::debug, fmt, args...);
+    }
+
+    template<typename FormatString, typename... Args>
+    void info(const FormatString &fmt, const Args &... args)
+    {
+        log(level::info, fmt, args...);
+    }
+
+    template<typename FormatString, typename... Args>
+    void warn(const FormatString &fmt, const Args &... args)
+    {
+        log(level::warn, fmt, args...);
+    }
+
+    template<typename FormatString, typename... Args>
+    void error(const FormatString &fmt, const Args &... args)
+    {
+        log(level::err, fmt, args...);
+    }
+
+    template<typename FormatString, typename... Args>
+    void critical(const FormatString &fmt, const Args &... args)
+    {
+        log(level::critical, fmt, args...);
+    }
+
+    template<typename T>
+    void log(level::level_enum lvl, const T &msg)
+    {
+        log(source_loc{}, lvl, msg);
+    }
+
+    // T can be statically converted to string_view and isn't a fmt::compile_string
+    template<class T, typename std::enable_if<
+                          std::is_convertible<const T &, spdlog::string_view_t>::value && !fmt::is_compile_string<T>::value, int>::type = 0>
+    void log(source_loc loc, level::level_enum lvl, const T &msg)
+    {
+        log(loc, lvl, string_view_t{msg});
+    }
+
+    void log(log_clock::time_point log_time, source_loc loc, level::level_enum lvl, string_view_t msg)
+    {
+        bool log_enabled = should_log(lvl);
+        bool traceback_enabled = tracer_.enabled();
+        if (!log_enabled && !traceback_enabled)
+        {
+            return;
+        }
+
+        details::log_msg log_msg(log_time, loc, name_, lvl, msg);
+        log_it_(log_msg, log_enabled, traceback_enabled);
+    }
+
+    void log(source_loc loc, level::level_enum lvl, string_view_t msg)
+    {
+        bool log_enabled = should_log(lvl);
+        bool traceback_enabled = tracer_.enabled();
+        if (!log_enabled && !traceback_enabled)
+        {
+            return;
+        }
+
+        details::log_msg log_msg(loc, name_, lvl, msg);
+        log_it_(log_msg, log_enabled, traceback_enabled);
+    }
+
+    void log(level::level_enum lvl, string_view_t msg)
+    {
+        log(source_loc{}, lvl, msg);
+    }
+
+    // T cannot be statically converted to string_view or wstring_view
+    template<class T, typename std::enable_if<!std::is_convertible<const T &, spdlog::string_view_t>::value &&
+                                                  !is_convertible_to_wstring_view<const T &>::value,
+                          int>::type = 0>
+    void log(source_loc loc, level::level_enum lvl, const T &msg)
+    {
+        log(loc, lvl, "{}", msg);
+    }
+
+    template<typename T>
+    void trace(const T &msg)
+    {
+        log(level::trace, msg);
+    }
+
+    template<typename T>
+    void debug(const T &msg)
+    {
+        log(level::debug, msg);
+    }
+
+    template<typename T>
+    void info(const T &msg)
+    {
+        log(level::info, msg);
+    }
+
+    template<typename T>
+    void warn(const T &msg)
+    {
+        log(level::warn, msg);
+    }
+
+    template<typename T>
+    void error(const T &msg)
+    {
+        log(level::err, msg);
+    }
+
+    template<typename T>
+    void critical(const T &msg)
+    {
+        log(level::critical, msg);
+    }
+
+#ifdef SPDLOG_WCHAR_TO_UTF8_SUPPORT
+#ifndef _WIN32
+#error SPDLOG_WCHAR_TO_UTF8_SUPPORT only supported on windows
+#else
+
+    template<typename... Args>
+    void log(source_loc loc, level::level_enum lvl, wstring_view_t fmt, const Args &... args)
+    {
+        bool log_enabled = should_log(lvl);
+        bool traceback_enabled = tracer_.enabled();
+        if (!log_enabled && !traceback_enabled)
+        {
+            return;
+        }
+        SPDLOG_TRY
+        {
+            // format to wmemory_buffer and convert to utf8
+            fmt::wmemory_buffer wbuf;
+            fmt::format_to(wbuf, fmt, args...);
+
+            memory_buf_t buf;
+            details::os::wstr_to_utf8buf(wstring_view_t(wbuf.data(), wbuf.size()), buf);
+            details::log_msg log_msg(loc, name_, lvl, string_view_t(buf.data(), buf.size()));
+            log_it_(log_msg, log_enabled, traceback_enabled);
+        }
+        SPDLOG_LOGGER_CATCH()
+    }
+
+    // T can be statically converted to wstring_view
+    template<class T, typename std::enable_if<is_convertible_to_wstring_view<const T &>::value, int>::type = 0>
+    void log(source_loc loc, level::level_enum lvl, const T &msg)
+    {
+        bool log_enabled = should_log(lvl);
+        bool traceback_enabled = tracer_.enabled();
+        if (!log_enabled && !traceback_enabled)
+        {
+            return;
+        }
+
+        SPDLOG_TRY
+        {
+            memory_buf_t buf;
+            details::os::wstr_to_utf8buf(msg, buf);
+            details::log_msg log_msg(loc, name_, lvl, string_view_t(buf.data(), buf.size()));
+            log_it_(log_msg, log_enabled, traceback_enabled);
+        }
+        SPDLOG_LOGGER_CATCH()
+    }
+#endif // _WIN32
+#endif // SPDLOG_WCHAR_TO_UTF8_SUPPORT
+
+    // return true logging is enabled for the given level.
+    bool should_log(level::level_enum msg_level) const
+    {
+        return msg_level >= level_.load(std::memory_order_relaxed);
+    }
+
+    // return true if backtrace logging is enabled.
+    bool should_backtrace() const
+    {
+        return tracer_.enabled();
+    }
+
+    void set_level(level::level_enum log_level);
+
+    level::level_enum level() const;
+
+    const std::string &name() const;
+
+    // set formatting for the sinks in this logger.
+    // each sink will get a separate instance of the formatter object.
+    void set_formatter(std::unique_ptr<formatter> f);
+
+    void set_pattern(std::string pattern, pattern_time_type time_type = pattern_time_type::local);
+
+    // backtrace support.
+    // efficiently store all debug/trace messages in a circular buffer until needed for debugging.
+    void enable_backtrace(size_t n_messages);
+    void disable_backtrace();
+    void dump_backtrace();
+
+    // flush functions
+    void flush();
+    void flush_on(level::level_enum log_level);
+    level::level_enum flush_level() const;
+
+    // sinks
+    const std::vector<sink_ptr> &sinks() const;
+
+    std::vector<sink_ptr> &sinks();
+
+    // error handler
+    void set_error_handler(err_handler);
+
+    // create new logger with same sinks and configuration.
+    virtual std::shared_ptr<logger> clone(std::string logger_name);
+
+protected:
+    std::string name_;
+    std::vector<sink_ptr> sinks_;
+    spdlog::level_t level_{level::info};
+    spdlog::level_t flush_level_{level::off};
+    err_handler custom_err_handler_{nullptr};
+    details::backtracer tracer_;
+
+    // common implementation for after templated public api has been resolved
+    template<typename FormatString, typename... Args>
+    void log_(source_loc loc, level::level_enum lvl, const FormatString &fmt, const Args &... args)
+    {
+        bool log_enabled = should_log(lvl);
+        bool traceback_enabled = tracer_.enabled();
+        if (!log_enabled && !traceback_enabled)
+        {
+            return;
+        }
+        SPDLOG_TRY
+        {
+            memory_buf_t buf;
+            fmt::format_to(buf, fmt, args...);
+            details::log_msg log_msg(loc, name_, lvl, string_view_t(buf.data(), buf.size()));
+            log_it_(log_msg, log_enabled, traceback_enabled);
+        }
+        SPDLOG_LOGGER_CATCH()
+    }
+
+    // log the given message (if the given log level is high enough),
+    // and save backtrace (if backtrace is enabled).
+    void log_it_(const details::log_msg &log_msg, bool log_enabled, bool traceback_enabled);
+    virtual void sink_it_(const details::log_msg &msg);
+    virtual void flush_();
+    void dump_backtrace_();
+    bool should_flush_(const details::log_msg &msg);
+
+    // handle errors during logging.
+    // default handler prints the error to stderr at max rate of 1 message/sec.
+    void err_handler_(const std::string &msg);
+};
+
+void swap(logger &a, logger &b);
+
+} // namespace spdlog
+
+#ifdef SPDLOG_HEADER_ONLY
+#include "logger-inl.h"
+#endif
--- a/src/spdlog/pattern_formatter-inl.h
+++ b/src/spdlog/pattern_formatter-inl.h
--- a/src/spdlog/pattern_formatter.h
+++ b/src/spdlog/pattern_formatter.h
@@ -0,0 +1,126 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include <spdlog/common.h>
+#include <spdlog/details/log_msg.h>
+#include <spdlog/details/os.h>
+#include <spdlog/formatter.h>
+
+#include <chrono>
+#include <ctime>
+#include <memory>
+
+#include <string>
+#include <vector>
+#include <unordered_map>
+
+namespace spdlog {
+namespace details {
+
+// padding information.
+struct padding_info
+{
+    enum pad_side
+    {
+        left,
+        right,
+        center
+    };
+
+    padding_info() = default;
+    padding_info(size_t width, padding_info::pad_side side, bool truncate)
+        : width_(width)
+        , side_(side)
+        , truncate_(truncate)
+        , enabled_(true)
+    {}
+
+    bool enabled() const
+    {
+        return enabled_;
+    }
+    size_t width_ = 0;
+    pad_side side_ = left;
+    bool truncate_ = false;
+    bool enabled_ = false;
+};
+
+class SPDLOG_API flag_formatter
+{
+public:
+    explicit flag_formatter(padding_info padinfo)
+        : padinfo_(padinfo)
+    {}
+    flag_formatter() = default;
+    virtual ~flag_formatter() = default;
+    virtual void format(const details::log_msg &msg, const std::tm &tm_time, memory_buf_t &dest) = 0;
+
+protected:
+    padding_info padinfo_;
+};
+
+} // namespace details
+
+class SPDLOG_API custom_flag_formatter : public details::flag_formatter
+{
+public:
+    virtual std::unique_ptr<custom_flag_formatter> clone() const = 0;
+
+    void set_padding_info(details::padding_info padding)
+    {
+        flag_formatter::padinfo_ = padding;
+    }
+};
+
+class SPDLOG_API pattern_formatter final : public formatter
+{
+public:
+    using custom_flags = std::unordered_map<char, std::unique_ptr<custom_flag_formatter>>;
+
+    explicit pattern_formatter(std::string pattern, pattern_time_type time_type = pattern_time_type::local,
+        std::string eol = spdlog::details::os::default_eol, custom_flags custom_user_flags = custom_flags());
+
+    // use default pattern is not given
+    explicit pattern_formatter(pattern_time_type time_type = pattern_time_type::local, std::string eol = spdlog::details::os::default_eol);
+
+    pattern_formatter(const pattern_formatter &other) = delete;
+    pattern_formatter &operator=(const pattern_formatter &other) = delete;
+
+    std::unique_ptr<formatter> clone() const override;
+    void format(const details::log_msg &msg, memory_buf_t &dest) override;
+
+    template<typename T, typename... Args>
+    pattern_formatter &add_flag(char flag, const Args &... args)
+    {
+        custom_handlers_[flag] = details::make_unique<T>(args...);
+        return *this;
+    }
+    void set_pattern(std::string pattern);
+
+private:
+    std::string pattern_;
+    std::string eol_;
+    pattern_time_type pattern_time_type_;
+    std::tm cached_tm_;
+    std::chrono::seconds last_log_secs_;
+    std::vector<std::unique_ptr<details::flag_formatter>> formatters_;
+    custom_flags custom_handlers_;
+
+    std::tm get_time_(const details::log_msg &msg);
+    template<typename Padder>
+    void handle_flag_(char flag, details::padding_info padding);
+
+    // Extract given pad spec (e.g. %8X)
+    // Advance the given it pass the end of the padding spec found (if any)
+    // Return padding.
+    static details::padding_info handle_padspec_(std::string::const_iterator &it, std::string::const_iterator end);
+
+    void compile_pattern_(const std::string &pattern);
+};
+} // namespace spdlog
+
+#ifdef SPDLOG_HEADER_ONLY
+#include "pattern_formatter-inl.h"
+#endif
--- a/src/spdlog/sinks/android_sink.h
+++ b/src/spdlog/sinks/android_sink.h
@@ -0,0 +1,119 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#ifdef __ANDROID__
+
+#include <spdlog/details/fmt_helper.h>
+#include <spdlog/details/null_mutex.h>
+#include <spdlog/details/os.h>
+#include <spdlog/sinks/base_sink.h>
+#include <spdlog/details/synchronous_factory.h>
+
+#include <android/log.h>
+#include <chrono>
+#include <mutex>
+#include <string>
+#include <thread>
+
+#if !defined(SPDLOG_ANDROID_RETRIES)
+#define SPDLOG_ANDROID_RETRIES 2
+#endif
+
+namespace spdlog {
+namespace sinks {
+
+/*
+ * Android sink (logging using __android_log_write)
+ */
+template<typename Mutex>
+class android_sink final : public base_sink<Mutex>
+{
+public:
+    explicit android_sink(std::string tag = "spdlog", bool use_raw_msg = false)
+        : tag_(std::move(tag))
+        , use_raw_msg_(use_raw_msg)
+    {}
+
+protected:
+    void sink_it_(const details::log_msg &msg) override
+    {
+        const android_LogPriority priority = convert_to_android_(msg.level);
+        memory_buf_t formatted;
+        if (use_raw_msg_)
+        {
+            details::fmt_helper::append_string_view(msg.payload, formatted);
+        }
+        else
+        {
+            base_sink<Mutex>::formatter_->format(msg, formatted);
+        }
+        formatted.push_back('\0');
+        const char *msg_output = formatted.data();
+
+        // See system/core/liblog/logger_write.c for explanation of return value
+        int ret = __android_log_write(priority, tag_.c_str(), msg_output);
+        int retry_count = 0;
+        while ((ret == -11 /*EAGAIN*/) && (retry_count < SPDLOG_ANDROID_RETRIES))
+        {
+            details::os::sleep_for_millis(5);
+            ret = __android_log_write(priority, tag_.c_str(), msg_output);
+            retry_count++;
+        }
+
+        if (ret < 0)
+        {
+            throw_spdlog_ex("__android_log_write() failed", ret);
+        }
+    }
+
+    void flush_() override {}
+
+private:
+    static android_LogPriority convert_to_android_(spdlog::level::level_enum level)
+    {
+        switch (level)
+        {
+        case spdlog::level::trace:
+            return ANDROID_LOG_VERBOSE;
+        case spdlog::level::debug:
+            return ANDROID_LOG_DEBUG;
+        case spdlog::level::info:
+            return ANDROID_LOG_INFO;
+        case spdlog::level::warn:
+            return ANDROID_LOG_WARN;
+        case spdlog::level::err:
+            return ANDROID_LOG_ERROR;
+        case spdlog::level::critical:
+            return ANDROID_LOG_FATAL;
+        default:
+            return ANDROID_LOG_DEFAULT;
+        }
+    }
+
+    std::string tag_;
+    bool use_raw_msg_;
+};
+
+using android_sink_mt = android_sink<std::mutex>;
+using android_sink_st = android_sink<details::null_mutex>;
+} // namespace sinks
+
+// Create and register android syslog logger
+
+template<typename Factory = spdlog::synchronous_factory>
+inline std::shared_ptr<logger> android_logger_mt(const std::string &logger_name, const std::string &tag = "spdlog")
+{
+    return Factory::template create<sinks::android_sink_mt>(logger_name, tag);
+}
+
+template<typename Factory = spdlog::synchronous_factory>
+inline std::shared_ptr<logger> android_logger_st(const std::string &logger_name, const std::string &tag = "spdlog")
+{
+    return Factory::template create<sinks::android_sink_st>(logger_name, tag);
+}
+
+} // namespace spdlog
+
+#endif // __ANDROID__
--- a/src/spdlog/sinks/ansicolor_sink-inl.h
+++ b/src/spdlog/sinks/ansicolor_sink-inl.h
@@ -0,0 +1,143 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#ifndef SPDLOG_HEADER_ONLY
+#include <spdlog/sinks/ansicolor_sink.h>
+#endif
+
+#include <spdlog/pattern_formatter.h>
+#include <spdlog/details/os.h>
+
+namespace spdlog {
+namespace sinks {
+
+template<typename ConsoleMutex>
+SPDLOG_INLINE ansicolor_sink<ConsoleMutex>::ansicolor_sink(FILE *target_file, color_mode mode)
+    : target_file_(target_file)
+    , mutex_(ConsoleMutex::mutex())
+    , formatter_(details::make_unique<spdlog::pattern_formatter>())
+
+{
+    set_color_mode(mode);
+    colors_[level::trace] = to_string_(white);
+    colors_[level::debug] = to_string_(cyan);
+    colors_[level::info] = to_string_(green);
+    colors_[level::warn] = to_string_(yellow_bold);
+    colors_[level::err] = to_string_(red_bold);
+    colors_[level::critical] = to_string_(bold_on_red);
+    colors_[level::off] = to_string_(reset);
+}
+
+template<typename ConsoleMutex>
+SPDLOG_INLINE void ansicolor_sink<ConsoleMutex>::set_color(level::level_enum color_level, string_view_t color)
+{
+    std::lock_guard<mutex_t> lock(mutex_);
+    colors_[color_level] = to_string_(color);
+}
+
+template<typename ConsoleMutex>
+SPDLOG_INLINE void ansicolor_sink<ConsoleMutex>::log(const details::log_msg &msg)
+{
+    // Wrap the originally formatted message in color codes.
+    // If color is not supported in the terminal, log as is instead.
+    std::lock_guard<mutex_t> lock(mutex_);
+    msg.color_range_start = 0;
+    msg.color_range_end = 0;
+    memory_buf_t formatted;
+    formatter_->format(msg, formatted);
+    if (should_do_colors_ && msg.color_range_end > msg.color_range_start)
+    {
+        // before color range
+        print_range_(formatted, 0, msg.color_range_start);
+        // in color range
+        print_ccode_(colors_[msg.level]);
+        print_range_(formatted, msg.color_range_start, msg.color_range_end);
+        print_ccode_(reset);
+        // after color range
+        print_range_(formatted, msg.color_range_end, formatted.size());
+    }
+    else // no color
+    {
+        print_range_(formatted, 0, formatted.size());
+    }
+    fflush(target_file_);
+}
+
+template<typename ConsoleMutex>
+SPDLOG_INLINE void ansicolor_sink<ConsoleMutex>::flush()
+{
+    std::lock_guard<mutex_t> lock(mutex_);
+    fflush(target_file_);
+}
+
+template<typename ConsoleMutex>
+SPDLOG_INLINE void ansicolor_sink<ConsoleMutex>::set_pattern(const std::string &pattern)
+{
+    std::lock_guard<mutex_t> lock(mutex_);
+    formatter_ = std::unique_ptr<spdlog::formatter>(new pattern_formatter(pattern));
+}
+
+template<typename ConsoleMutex>
+SPDLOG_INLINE void ansicolor_sink<ConsoleMutex>::set_formatter(std::unique_ptr<spdlog::formatter> sink_formatter)
+{
+    std::lock_guard<mutex_t> lock(mutex_);
+    formatter_ = std::move(sink_formatter);
+}
+
+template<typename ConsoleMutex>
+SPDLOG_INLINE bool ansicolor_sink<ConsoleMutex>::should_color()
+{
+    return should_do_colors_;
+}
+
+template<typename ConsoleMutex>
+SPDLOG_INLINE void ansicolor_sink<ConsoleMutex>::set_color_mode(color_mode mode)
+{
+    switch (mode)
+    {
+    case color_mode::always:
+        should_do_colors_ = true;
+        return;
+    case color_mode::automatic:
+        should_do_colors_ = details::os::in_terminal(target_file_) && details::os::is_color_terminal();
+        return;
+    case color_mode::never:
+        should_do_colors_ = false;
+        return;
+    }
+}
+
+template<typename ConsoleMutex>
+SPDLOG_INLINE void ansicolor_sink<ConsoleMutex>::print_ccode_(const string_view_t &color_code)
+{
+    fwrite(color_code.data(), sizeof(char), color_code.size(), target_file_);
+}
+
+template<typename ConsoleMutex>
+SPDLOG_INLINE void ansicolor_sink<ConsoleMutex>::print_range_(const memory_buf_t &formatted, size_t start, size_t end)
+{
+    fwrite(formatted.data() + start, sizeof(char), end - start, target_file_);
+}
+
+template<typename ConsoleMutex>
+SPDLOG_INLINE std::string ansicolor_sink<ConsoleMutex>::to_string_(const string_view_t &sv)
+{
+    return std::string(sv.data(), sv.size());
+}
+
+// ansicolor_stdout_sink
+template<typename ConsoleMutex>
+SPDLOG_INLINE ansicolor_stdout_sink<ConsoleMutex>::ansicolor_stdout_sink(color_mode mode)
+    : ansicolor_sink<ConsoleMutex>(stdout, mode)
+{}
+
+// ansicolor_stderr_sink
+template<typename ConsoleMutex>
+SPDLOG_INLINE ansicolor_stderr_sink<ConsoleMutex>::ansicolor_stderr_sink(color_mode mode)
+    : ansicolor_sink<ConsoleMutex>(stderr, mode)
+{}
+
+} // namespace sinks
+} // namespace spdlog
--- a/src/spdlog/sinks/ansicolor_sink.h
+++ b/src/spdlog/sinks/ansicolor_sink.h
@@ -0,0 +1,118 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include <spdlog/details/console_globals.h>
+#include <spdlog/details/null_mutex.h>
+#include <spdlog/sinks/sink.h>
+#include <memory>
+#include <mutex>
+#include <string>
+#include <array>
+
+namespace spdlog {
+namespace sinks {
+
+/**
+ * This sink prefixes the output with an ANSI escape sequence color code
+ * depending on the severity
+ * of the message.
+ * If no color terminal detected, omit the escape codes.
+ */
+
+template<typename ConsoleMutex>
+class ansicolor_sink : public sink
+{
+public:
+    using mutex_t = typename ConsoleMutex::mutex_t;
+    ansicolor_sink(FILE *target_file, color_mode mode);
+    ~ansicolor_sink() override = default;
+
+    ansicolor_sink(const ansicolor_sink &other) = delete;
+    ansicolor_sink(ansicolor_sink &&other) = delete;
+
+    ansicolor_sink &operator=(const ansicolor_sink &other) = delete;
+    ansicolor_sink &operator=(ansicolor_sink &&other) = delete;
+
+    void set_color(level::level_enum color_level, string_view_t color);
+    void set_color_mode(color_mode mode);
+    bool should_color();
+
+    void log(const details::log_msg &msg) override;
+    void flush() override;
+    void set_pattern(const std::string &pattern) final;
+    void set_formatter(std::unique_ptr<spdlog::formatter> sink_formatter) override;
+
+    // Formatting codes
+    const string_view_t reset = "\033[m";
+    const string_view_t bold = "\033[1m";
+    const string_view_t dark = "\033[2m";
+    const string_view_t underline = "\033[4m";
+    const string_view_t blink = "\033[5m";
+    const string_view_t reverse = "\033[7m";
+    const string_view_t concealed = "\033[8m";
+    const string_view_t clear_line = "\033[K";
+
+    // Foreground colors
+    const string_view_t black = "\033[30m";
+    const string_view_t red = "\033[31m";
+    const string_view_t green = "\033[32m";
+    const string_view_t yellow = "\033[33m";
+    const string_view_t blue = "\033[34m";
+    const string_view_t magenta = "\033[35m";
+    const string_view_t cyan = "\033[36m";
+    const string_view_t white = "\033[37m";
+
+    /// Background colors
+    const string_view_t on_black = "\033[40m";
+    const string_view_t on_red = "\033[41m";
+    const string_view_t on_green = "\033[42m";
+    const string_view_t on_yellow = "\033[43m";
+    const string_view_t on_blue = "\033[44m";
+    const string_view_t on_magenta = "\033[45m";
+    const string_view_t on_cyan = "\033[46m";
+    const string_view_t on_white = "\033[47m";
+
+    /// Bold colors
+    const string_view_t yellow_bold = "\033[33m\033[1m";
+    const string_view_t red_bold = "\033[31m\033[1m";
+    const string_view_t bold_on_red = "\033[1m\033[41m";
+
+private:
+    FILE *target_file_;
+    mutex_t &mutex_;
+    bool should_do_colors_;
+    std::unique_ptr<spdlog::formatter> formatter_;
+    std::array<std::string, level::n_levels> colors_;
+    void print_ccode_(const string_view_t &color_code);
+    void print_range_(const memory_buf_t &formatted, size_t start, size_t end);
+    static std::string to_string_(const string_view_t &sv);
+};
+
+template<typename ConsoleMutex>
+class ansicolor_stdout_sink : public ansicolor_sink<ConsoleMutex>
+{
+public:
+    explicit ansicolor_stdout_sink(color_mode mode = color_mode::automatic);
+};
+
+template<typename ConsoleMutex>
+class ansicolor_stderr_sink : public ansicolor_sink<ConsoleMutex>
+{
+public:
+    explicit ansicolor_stderr_sink(color_mode mode = color_mode::automatic);
+};
+
+using ansicolor_stdout_sink_mt = ansicolor_stdout_sink<details::console_mutex>;
+using ansicolor_stdout_sink_st = ansicolor_stdout_sink<details::console_nullmutex>;
+
+using ansicolor_stderr_sink_mt = ansicolor_stderr_sink<details::console_mutex>;
+using ansicolor_stderr_sink_st = ansicolor_stderr_sink<details::console_nullmutex>;
+
+} // namespace sinks
+} // namespace spdlog
+
+#ifdef SPDLOG_HEADER_ONLY
+#include "ansicolor_sink-inl.h"
+#endif
--- a/src/spdlog/sinks/base_sink-inl.h
+++ b/src/spdlog/sinks/base_sink-inl.h
@@ -0,0 +1,63 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#ifndef SPDLOG_HEADER_ONLY
+#include <spdlog/sinks/base_sink.h>
+#endif
+
+#include <spdlog/common.h>
+#include <spdlog/pattern_formatter.h>
+
+#include <memory>
+
+template<typename Mutex>
+SPDLOG_INLINE spdlog::sinks::base_sink<Mutex>::base_sink()
+    : formatter_{details::make_unique<spdlog::pattern_formatter>()}
+{}
+
+template<typename Mutex>
+SPDLOG_INLINE spdlog::sinks::base_sink<Mutex>::base_sink(std::unique_ptr<spdlog::formatter> formatter)
+    : formatter_{std::move(formatter)}
+{}
+
+template<typename Mutex>
+void SPDLOG_INLINE spdlog::sinks::base_sink<Mutex>::log(const details::log_msg &msg)
+{
+    std::lock_guard<Mutex> lock(mutex_);
+    sink_it_(msg);
+}
+
+template<typename Mutex>
+void SPDLOG_INLINE spdlog::sinks::base_sink<Mutex>::flush()
+{
+    std::lock_guard<Mutex> lock(mutex_);
+    flush_();
+}
+
+template<typename Mutex>
+void SPDLOG_INLINE spdlog::sinks::base_sink<Mutex>::set_pattern(const std::string &pattern)
+{
+    std::lock_guard<Mutex> lock(mutex_);
+    set_pattern_(pattern);
+}
+
+template<typename Mutex>
+void SPDLOG_INLINE spdlog::sinks::base_sink<Mutex>::set_formatter(std::unique_ptr<spdlog::formatter> sink_formatter)
+{
+    std::lock_guard<Mutex> lock(mutex_);
+    set_formatter_(std::move(sink_formatter));
+}
+
+template<typename Mutex>
+void SPDLOG_INLINE spdlog::sinks::base_sink<Mutex>::set_pattern_(const std::string &pattern)
+{
+    set_formatter_(details::make_unique<spdlog::pattern_formatter>(pattern));
+}
+
+template<typename Mutex>
+void SPDLOG_INLINE spdlog::sinks::base_sink<Mutex>::set_formatter_(std::unique_ptr<spdlog::formatter> sink_formatter)
+{
+    formatter_ = std::move(sink_formatter);
+}
--- a/src/spdlog/sinks/base_sink.h
+++ b/src/spdlog/sinks/base_sink.h
@@ -0,0 +1,52 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+//
+// base sink templated over a mutex (either dummy or real)
+// concrete implementation should override the sink_it_() and flush_()  methods.
+// locking is taken care of in this class - no locking needed by the
+// implementers..
+//
+
+#include <spdlog/common.h>
+#include <spdlog/details/log_msg.h>
+#include <spdlog/sinks/sink.h>
+
+namespace spdlog {
+namespace sinks {
+template<typename Mutex>
+class base_sink : public sink
+{
+public:
+    base_sink();
+    explicit base_sink(std::unique_ptr<spdlog::formatter> formatter);
+    ~base_sink() override = default;
+
+    base_sink(const base_sink &) = delete;
+    base_sink(base_sink &&) = delete;
+
+    base_sink &operator=(const base_sink &) = delete;
+    base_sink &operator=(base_sink &&) = delete;
+
+    void log(const details::log_msg &msg) final;
+    void flush() final;
+    void set_pattern(const std::string &pattern) final;
+    void set_formatter(std::unique_ptr<spdlog::formatter> sink_formatter) final;
+
+protected:
+    // sink formatter
+    std::unique_ptr<spdlog::formatter> formatter_;
+    Mutex mutex_;
+
+    virtual void sink_it_(const details::log_msg &msg) = 0;
+    virtual void flush_() = 0;
+    virtual void set_pattern_(const std::string &pattern);
+    virtual void set_formatter_(std::unique_ptr<spdlog::formatter> sink_formatter);
+};
+} // namespace sinks
+} // namespace spdlog
+
+#ifdef SPDLOG_HEADER_ONLY
+#include "base_sink-inl.h"
+#endif
--- a/src/spdlog/sinks/basic_file_sink-inl.h
+++ b/src/spdlog/sinks/basic_file_sink-inl.h
@@ -0,0 +1,43 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#ifndef SPDLOG_HEADER_ONLY
+#include <spdlog/sinks/basic_file_sink.h>
+#endif
+
+#include <spdlog/common.h>
+#include <spdlog/details/os.h>
+
+namespace spdlog {
+namespace sinks {
+
+template<typename Mutex>
+SPDLOG_INLINE basic_file_sink<Mutex>::basic_file_sink(const filename_t &filename, bool truncate)
+{
+    file_helper_.open(filename, truncate);
+}
+
+template<typename Mutex>
+SPDLOG_INLINE const filename_t &basic_file_sink<Mutex>::filename() const
+{
+    return file_helper_.filename();
+}
+
+template<typename Mutex>
+SPDLOG_INLINE void basic_file_sink<Mutex>::sink_it_(const details::log_msg &msg)
+{
+    memory_buf_t formatted;
+    base_sink<Mutex>::formatter_->format(msg, formatted);
+    file_helper_.write(formatted);
+}
+
+template<typename Mutex>
+SPDLOG_INLINE void basic_file_sink<Mutex>::flush_()
+{
+    file_helper_.flush();
+}
+
+} // namespace sinks
+} // namespace spdlog
--- a/src/spdlog/sinks/basic_file_sink.h
+++ b/src/spdlog/sinks/basic_file_sink.h
@@ -0,0 +1,58 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include <spdlog/details/file_helper.h>
+#include <spdlog/details/null_mutex.h>
+#include <spdlog/sinks/base_sink.h>
+#include <spdlog/details/synchronous_factory.h>
+
+#include <mutex>
+#include <string>
+
+namespace spdlog {
+namespace sinks {
+/*
+ * Trivial file sink with single file as target
+ */
+template<typename Mutex>
+class basic_file_sink final : public base_sink<Mutex>
+{
+public:
+    explicit basic_file_sink(const filename_t &filename, bool truncate = false);
+    const filename_t &filename() const;
+
+protected:
+    void sink_it_(const details::log_msg &msg) override;
+    void flush_() override;
+
+private:
+    details::file_helper file_helper_;
+};
+
+using basic_file_sink_mt = basic_file_sink<std::mutex>;
+using basic_file_sink_st = basic_file_sink<details::null_mutex>;
+
+} // namespace sinks
+
+//
+// factory functions
+//
+template<typename Factory = spdlog::synchronous_factory>
+inline std::shared_ptr<logger> basic_logger_mt(const std::string &logger_name, const filename_t &filename, bool truncate = false)
+{
+    return Factory::template create<sinks::basic_file_sink_mt>(logger_name, filename, truncate);
+}
+
+template<typename Factory = spdlog::synchronous_factory>
+inline std::shared_ptr<logger> basic_logger_st(const std::string &logger_name, const filename_t &filename, bool truncate = false)
+{
+    return Factory::template create<sinks::basic_file_sink_st>(logger_name, filename, truncate);
+}
+
+} // namespace spdlog
+
+#ifdef SPDLOG_HEADER_ONLY
+#include "basic_file_sink-inl.h"
+#endif
--- a/src/spdlog/sinks/daily_file_sink.h
+++ b/src/spdlog/sinks/daily_file_sink.h
@@ -0,0 +1,204 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include <spdlog/common.h>
+#include <spdlog/details/file_helper.h>
+#include <spdlog/details/null_mutex.h>
+#include <spdlog/fmt/fmt.h>
+#include <spdlog/sinks/base_sink.h>
+#include <spdlog/details/os.h>
+#include <spdlog/details/circular_q.h>
+#include <spdlog/details/synchronous_factory.h>
+
+#include <chrono>
+#include <cstdio>
+#include <ctime>
+#include <mutex>
+#include <string>
+
+namespace spdlog {
+namespace sinks {
+
+/*
+ * Generator of daily log file names in format basename.YYYY-MM-DD.ext
+ */
+struct daily_filename_calculator
+{
+    // Create filename for the form basename.YYYY-MM-DD
+    static filename_t calc_filename(const filename_t &filename, const tm &now_tm)
+    {
+        filename_t basename, ext;
+        std::tie(basename, ext) = details::file_helper::split_by_extension(filename);
+        return fmt::format(
+            SPDLOG_FILENAME_T("{}_{:04d}-{:02d}-{:02d}{}"), basename, now_tm.tm_year + 1900, now_tm.tm_mon + 1, now_tm.tm_mday, ext);
+    }
+};
+
+/*
+ * Rotating file sink based on date.
+ * If truncate != false , the created file will be truncated.
+ * If max_files > 0, retain only the last max_files and delete previous.
+ */
+template<typename Mutex, typename FileNameCalc = daily_filename_calculator>
+class daily_file_sink final : public base_sink<Mutex>
+{
+public:
+    // create daily file sink which rotates on given time
+    daily_file_sink(filename_t base_filename, int rotation_hour, int rotation_minute, bool truncate = false, uint16_t max_files = 0)
+        : base_filename_(std::move(base_filename))
+        , rotation_h_(rotation_hour)
+        , rotation_m_(rotation_minute)
+        , truncate_(truncate)
+        , max_files_(max_files)
+        , filenames_q_()
+    {
+        if (rotation_hour < 0 || rotation_hour > 23 || rotation_minute < 0 || rotation_minute > 59)
+        {
+            throw_spdlog_ex("daily_file_sink: Invalid rotation time in ctor");
+        }
+
+        auto now = log_clock::now();
+        auto filename = FileNameCalc::calc_filename(base_filename_, now_tm(now));
+        file_helper_.open(filename, truncate_);
+        rotation_tp_ = next_rotation_tp_();
+
+        if (max_files_ > 0)
+        {
+            init_filenames_q_();
+        }
+    }
+
+    filename_t filename()
+    {
+        std::lock_guard<Mutex> lock(base_sink<Mutex>::mutex_);
+        return file_helper_.filename();
+    }
+
+protected:
+    void sink_it_(const details::log_msg &msg) override
+    {
+        auto time = msg.time;
+        bool should_rotate = time >= rotation_tp_;
+        if (should_rotate)
+        {
+            auto filename = FileNameCalc::calc_filename(base_filename_, now_tm(time));
+            file_helper_.open(filename, truncate_);
+            rotation_tp_ = next_rotation_tp_();
+        }
+        memory_buf_t formatted;
+        base_sink<Mutex>::formatter_->format(msg, formatted);
+        file_helper_.write(formatted);
+
+        // Do the cleaning only at the end because it might throw on failure.
+        if (should_rotate && max_files_ > 0)
+        {
+            delete_old_();
+        }
+    }
+
+    void flush_() override
+    {
+        file_helper_.flush();
+    }
+
+private:
+    void init_filenames_q_()
+    {
+        using details::os::path_exists;
+
+        filenames_q_ = details::circular_q<filename_t>(static_cast<size_t>(max_files_));
+        std::vector<filename_t> filenames;
+        auto now = log_clock::now();
+        while (filenames.size() < max_files_)
+        {
+            auto filename = FileNameCalc::calc_filename(base_filename_, now_tm(now));
+            if (!path_exists(filename))
+            {
+                break;
+            }
+            filenames.emplace_back(filename);
+            now -= std::chrono::hours(24);
+        }
+        for (auto iter = filenames.rbegin(); iter != filenames.rend(); ++iter)
+        {
+            filenames_q_.push_back(std::move(*iter));
+        }
+    }
+
+    tm now_tm(log_clock::time_point tp)
+    {
+        time_t tnow = log_clock::to_time_t(tp);
+        return spdlog::details::os::localtime(tnow);
+    }
+
+    log_clock::time_point next_rotation_tp_()
+    {
+        auto now = log_clock::now();
+        tm date = now_tm(now);
+        date.tm_hour = rotation_h_;
+        date.tm_min = rotation_m_;
+        date.tm_sec = 0;
+        auto rotation_time = log_clock::from_time_t(std::mktime(&date));
+        if (rotation_time > now)
+        {
+            return rotation_time;
+        }
+        return {rotation_time + std::chrono::hours(24)};
+    }
+
+    // Delete the file N rotations ago.
+    // Throw spdlog_ex on failure to delete the old file.
+    void delete_old_()
+    {
+        using details::os::filename_to_str;
+        using details::os::remove_if_exists;
+
+        filename_t current_file = file_helper_.filename();
+        if (filenames_q_.full())
+        {
+            auto old_filename = std::move(filenames_q_.front());
+            filenames_q_.pop_front();
+            bool ok = remove_if_exists(old_filename) == 0;
+            if (!ok)
+            {
+                filenames_q_.push_back(std::move(current_file));
+                throw_spdlog_ex("Failed removing daily file " + filename_to_str(old_filename), errno);
+            }
+        }
+        filenames_q_.push_back(std::move(current_file));
+    }
+
+    filename_t base_filename_;
+    int rotation_h_;
+    int rotation_m_;
+    log_clock::time_point rotation_tp_;
+    details::file_helper file_helper_;
+    bool truncate_;
+    uint16_t max_files_;
+    details::circular_q<filename_t> filenames_q_;
+};
+
+using daily_file_sink_mt = daily_file_sink<std::mutex>;
+using daily_file_sink_st = daily_file_sink<details::null_mutex>;
+
+} // namespace sinks
+
+//
+// factory functions
+//
+template<typename Factory = spdlog::synchronous_factory>
+inline std::shared_ptr<logger> daily_logger_mt(
+    const std::string &logger_name, const filename_t &filename, int hour = 0, int minute = 0, bool truncate = false, uint16_t max_files = 0)
+{
+    return Factory::template create<sinks::daily_file_sink_mt>(logger_name, filename, hour, minute, truncate, max_files);
+}
+
+template<typename Factory = spdlog::synchronous_factory>
+inline std::shared_ptr<logger> daily_logger_st(
+    const std::string &logger_name, const filename_t &filename, int hour = 0, int minute = 0, bool truncate = false, uint16_t max_files = 0)
+{
+    return Factory::template create<sinks::daily_file_sink_st>(logger_name, filename, hour, minute, truncate, max_files);
+}
+} // namespace spdlog
--- a/src/spdlog/sinks/dist_sink.h
+++ b/src/spdlog/sinks/dist_sink.h
@@ -0,0 +1,97 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include "base_sink.h"
+#include <spdlog/details/log_msg.h>
+#include <spdlog/details/null_mutex.h>
+#include <spdlog/pattern_formatter.h>
+
+#include <algorithm>
+#include <memory>
+#include <mutex>
+#include <vector>
+
+// Distribution sink (mux). Stores a vector of sinks which get called when log
+// is called
+
+namespace spdlog {
+namespace sinks {
+
+template<typename Mutex>
+class dist_sink : public base_sink<Mutex>
+{
+public:
+    dist_sink() = default;
+    explicit dist_sink(std::vector<std::shared_ptr<sink>> sinks)
+        : sinks_(sinks)
+    {}
+
+    dist_sink(const dist_sink &) = delete;
+    dist_sink &operator=(const dist_sink &) = delete;
+
+    void add_sink(std::shared_ptr<sink> sink)
+    {
+        std::lock_guard<Mutex> lock(base_sink<Mutex>::mutex_);
+        sinks_.push_back(sink);
+    }
+
+    void remove_sink(std::shared_ptr<sink> sink)
+    {
+        std::lock_guard<Mutex> lock(base_sink<Mutex>::mutex_);
+        sinks_.erase(std::remove(sinks_.begin(), sinks_.end(), sink), sinks_.end());
+    }
+
+    void set_sinks(std::vector<std::shared_ptr<sink>> sinks)
+    {
+        std::lock_guard<Mutex> lock(base_sink<Mutex>::mutex_);
+        sinks_ = std::move(sinks);
+    }
+
+    std::vector<std::shared_ptr<sink>> &sinks()
+    {
+        return sinks_;
+    }
+
+protected:
+    void sink_it_(const details::log_msg &msg) override
+    {
+        for (auto &sink : sinks_)
+        {
+            if (sink->should_log(msg.level))
+            {
+                sink->log(msg);
+            }
+        }
+    }
+
+    void flush_() override
+    {
+        for (auto &sink : sinks_)
+        {
+            sink->flush();
+        }
+    }
+
+    void set_pattern_(const std::string &pattern) override
+    {
+        set_formatter_(details::make_unique<spdlog::pattern_formatter>(pattern));
+    }
+
+    void set_formatter_(std::unique_ptr<spdlog::formatter> sink_formatter) override
+    {
+        base_sink<Mutex>::formatter_ = std::move(sink_formatter);
+        for (auto &sink : sinks_)
+        {
+            sink->set_formatter(base_sink<Mutex>::formatter_->clone());
+        }
+    }
+    std::vector<std::shared_ptr<sink>> sinks_;
+};
+
+using dist_sink_mt = dist_sink<std::mutex>;
+using dist_sink_st = dist_sink<details::null_mutex>;
+
+} // namespace sinks
+} // namespace spdlog
--- a/src/spdlog/sinks/dup_filter_sink.h
+++ b/src/spdlog/sinks/dup_filter_sink.h
@@ -0,0 +1,90 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include "dist_sink.h"
+#include <spdlog/details/null_mutex.h>
+#include <spdlog/details/log_msg.h>
+
+#include <mutex>
+#include <string>
+#include <chrono>
+
+// Duplicate message removal sink.
+// Skip the message if previous one is identical and less than "max_skip_duration" have passed
+//
+// Example:
+//
+//     #include <spdlog/sinks/dup_filter_sink.h>
+//
+//     int main() {
+//         auto dup_filter = std::make_shared<dup_filter_sink_st>(std::chrono::seconds(5));
+//         dup_filter->add_sink(std::make_shared<stdout_color_sink_mt>());
+//         spdlog::logger l("logger", dup_filter);
+//         l.info("Hello");
+//         l.info("Hello");
+//         l.info("Hello");
+//         l.info("Different Hello");
+//     }
+//
+// Will produce:
+//       [2019-06-25 17:50:56.511] [logger] [info] Hello
+//       [2019-06-25 17:50:56.512] [logger] [info] Skipped 3 duplicate messages..
+//       [2019-06-25 17:50:56.512] [logger] [info] Different Hello
+
+namespace spdlog {
+namespace sinks {
+template<typename Mutex>
+class dup_filter_sink : public dist_sink<Mutex>
+{
+public:
+    template<class Rep, class Period>
+    explicit dup_filter_sink(std::chrono::duration<Rep, Period> max_skip_duration)
+        : max_skip_duration_{max_skip_duration}
+    {}
+
+protected:
+    std::chrono::microseconds max_skip_duration_;
+    log_clock::time_point last_msg_time_;
+    std::string last_msg_payload_;
+    size_t skip_counter_ = 0;
+
+    void sink_it_(const details::log_msg &msg) override
+    {
+        bool filtered = filter_(msg);
+        if (!filtered)
+        {
+            skip_counter_ += 1;
+            return;
+        }
+
+        // log the "skipped.." message
+        if (skip_counter_ > 0)
+        {
+            memory_buf_t buf;
+            fmt::format_to(buf, "Skipped {} duplicate messages..", skip_counter_);
+            details::log_msg skipped_msg{msg.logger_name, msg.level, string_view_t{buf.data(), buf.size()}};
+            dist_sink<Mutex>::sink_it_(skipped_msg);
+        }
+
+        // log current message
+        dist_sink<Mutex>::sink_it_(msg);
+        last_msg_time_ = msg.time;
+        skip_counter_ = 0;
+        last_msg_payload_.assign(msg.payload.data(), msg.payload.data() + msg.payload.size());
+    }
+
+    // return whether the log msg should be displayed (true) or skipped (false)
+    bool filter_(const details::log_msg &msg)
+    {
+        auto filter_duration = msg.time - last_msg_time_;
+        return (filter_duration > max_skip_duration_) || (msg.payload != last_msg_payload_);
+    }
+};
+
+using dup_filter_sink_mt = dup_filter_sink<std::mutex>;
+using dup_filter_sink_st = dup_filter_sink<details::null_mutex>;
+
+} // namespace sinks
+} // namespace spdlog
--- a/src/spdlog/sinks/msvc_sink.h
+++ b/src/spdlog/sinks/msvc_sink.h
@@ -0,0 +1,49 @@
+// Copyright(c) 2016 Alexander Dalshov.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#if defined(_WIN32)
+
+#include <spdlog/details/null_mutex.h>
+#include <spdlog/sinks/base_sink.h>
+
+#include <spdlog/details/windows_include.h>
+#include <winbase.h>
+
+#include <mutex>
+#include <string>
+
+namespace spdlog {
+namespace sinks {
+/*
+ * MSVC sink (logging using OutputDebugStringA)
+ */
+template<typename Mutex>
+class msvc_sink : public base_sink<Mutex>
+{
+public:
+    explicit msvc_sink() {}
+
+protected:
+    void sink_it_(const details::log_msg &msg) override
+    {
+
+        memory_buf_t formatted;
+        base_sink<Mutex>::formatter_->format(msg, formatted);
+        OutputDebugStringA(fmt::to_string(formatted).c_str());
+    }
+
+    void flush_() override {}
+};
+
+using msvc_sink_mt = msvc_sink<std::mutex>;
+using msvc_sink_st = msvc_sink<details::null_mutex>;
+
+using windebug_sink_mt = msvc_sink_mt;
+using windebug_sink_st = msvc_sink_st;
+
+} // namespace sinks
+} // namespace spdlog
+
+#endif
--- a/src/spdlog/sinks/null_sink.h
+++ b/src/spdlog/sinks/null_sink.h
@@ -0,0 +1,44 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include <spdlog/details/null_mutex.h>
+#include <spdlog/sinks/base_sink.h>
+#include <spdlog/details/synchronous_factory.h>
+
+#include <mutex>
+
+namespace spdlog {
+namespace sinks {
+
+template<typename Mutex>
+class null_sink : public base_sink<Mutex>
+{
+protected:
+    void sink_it_(const details::log_msg &) override {}
+    void flush_() override {}
+};
+
+using null_sink_mt = null_sink<details::null_mutex>;
+using null_sink_st = null_sink<details::null_mutex>;
+
+} // namespace sinks
+
+template<typename Factory = spdlog::synchronous_factory>
+inline std::shared_ptr<logger> null_logger_mt(const std::string &logger_name)
+{
+    auto null_logger = Factory::template create<sinks::null_sink_mt>(logger_name);
+    null_logger->set_level(level::off);
+    return null_logger;
+}
+
+template<typename Factory = spdlog::synchronous_factory>
+inline std::shared_ptr<logger> null_logger_st(const std::string &logger_name)
+{
+    auto null_logger = Factory::template create<sinks::null_sink_st>(logger_name);
+    null_logger->set_level(level::off);
+    return null_logger;
+}
+
+} // namespace spdlog
--- a/src/spdlog/sinks/ostream_sink.h
+++ b/src/spdlog/sinks/ostream_sink.h
@@ -0,0 +1,50 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include <spdlog/details/null_mutex.h>
+#include <spdlog/sinks/base_sink.h>
+
+#include <mutex>
+#include <ostream>
+
+namespace spdlog {
+namespace sinks {
+template<typename Mutex>
+class ostream_sink final : public base_sink<Mutex>
+{
+public:
+    explicit ostream_sink(std::ostream &os, bool force_flush = false)
+        : ostream_(os)
+        , force_flush_(force_flush)
+    {}
+    ostream_sink(const ostream_sink &) = delete;
+    ostream_sink &operator=(const ostream_sink &) = delete;
+
+protected:
+    void sink_it_(const details::log_msg &msg) override
+    {
+        memory_buf_t formatted;
+        base_sink<Mutex>::formatter_->format(msg, formatted);
+        ostream_.write(formatted.data(), static_cast<std::streamsize>(formatted.size()));
+        if (force_flush_)
+        {
+            ostream_.flush();
+        }
+    }
+
+    void flush_() override
+    {
+        ostream_.flush();
+    }
+
+    std::ostream &ostream_;
+    bool force_flush_;
+};
+
+using ostream_sink_mt = ostream_sink<std::mutex>;
+using ostream_sink_st = ostream_sink<details::null_mutex>;
+
+} // namespace sinks
+} // namespace spdlog
--- a/src/spdlog/sinks/ringbuffer_sink.h
+++ b/src/spdlog/sinks/ringbuffer_sink.h
@@ -0,0 +1,74 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include "spdlog/sinks/base_sink.h"
+#include "spdlog/details/circular_q.h"
+#include "spdlog/details/log_msg_buffer.h"
+#include "spdlog/details/null_mutex.h"
+
+#include <mutex>
+#include <string>
+#include <vector>
+
+namespace spdlog {
+namespace sinks {
+/*
+ * Ring buffer sink
+ */
+template<typename Mutex>
+class ringbuffer_sink final : public base_sink<Mutex>
+{
+public:
+    explicit ringbuffer_sink(size_t n_items)
+        : q_{n_items}
+    {}
+
+    std::vector<details::log_msg_buffer> last_raw(size_t lim = 0)
+    {
+        std::lock_guard<Mutex> lock(base_sink<Mutex>::mutex_);
+        auto items_available = q_.size();
+        auto n_items = lim > 0 ? (std::min)(lim, items_available) : items_available;
+        std::vector<details::log_msg_buffer> ret;
+        ret.reserve(n_items);
+        for (size_t i = (items_available - n_items); i < items_available; i++)
+        {
+            ret.push_back(q_.at(i));
+        }
+        return ret;
+    }
+
+    std::vector<std::string> last_formatted(size_t lim = 0)
+    {
+        std::lock_guard<Mutex> lock(base_sink<Mutex>::mutex_);
+        auto items_available = q_.size();
+        auto n_items = lim > 0 ? (std::min)(lim, items_available) : items_available;
+        std::vector<std::string> ret;
+        ret.reserve(n_items);
+        for (size_t i = (items_available - n_items); i < items_available; i++)
+        {
+            memory_buf_t formatted;
+            base_sink<Mutex>::formatter_->format(q_.at(i), formatted);
+            ret.push_back(fmt::to_string(formatted));
+        }
+        return ret;
+    }
+
+protected:
+    void sink_it_(const details::log_msg &msg) override
+    {
+        q_.push_back(details::log_msg_buffer{msg});
+    }
+    void flush_() override {}
+
+private:
+    details::circular_q<details::log_msg_buffer> q_;
+};
+
+using ringbuffer_sink_mt = ringbuffer_sink<std::mutex>;
+using ringbuffer_sink_st = ringbuffer_sink<details::null_mutex>;
+
+} // namespace sinks
+
+} // namespace spdlog
--- a/src/spdlog/sinks/rotating_file_sink-inl.h
+++ b/src/spdlog/sinks/rotating_file_sink-inl.h
@@ -0,0 +1,131 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#ifndef SPDLOG_HEADER_ONLY
+#include <spdlog/sinks/rotating_file_sink.h>
+#endif
+
+#include <spdlog/common.h>
+
+#include <spdlog/details/file_helper.h>
+#include <spdlog/details/null_mutex.h>
+#include <spdlog/fmt/fmt.h>
+
+#include <cerrno>
+#include <chrono>
+#include <ctime>
+#include <mutex>
+#include <string>
+#include <tuple>
+
+namespace spdlog {
+namespace sinks {
+
+template<typename Mutex>
+SPDLOG_INLINE rotating_file_sink<Mutex>::rotating_file_sink(
+    filename_t base_filename, std::size_t max_size, std::size_t max_files, bool rotate_on_open)
+    : base_filename_(std::move(base_filename))
+    , max_size_(max_size)
+    , max_files_(max_files)
+{
+    file_helper_.open(calc_filename(base_filename_, 0));
+    current_size_ = file_helper_.size(); // expensive. called only once
+    if (rotate_on_open && current_size_ > 0)
+    {
+        rotate_();
+    }
+}
+
+// calc filename according to index and file extension if exists.
+// e.g. calc_filename("logs/mylog.txt, 3) => "logs/mylog.3.txt".
+template<typename Mutex>
+SPDLOG_INLINE filename_t rotating_file_sink<Mutex>::calc_filename(const filename_t &filename, std::size_t index)
+{
+    if (index == 0u)
+    {
+        return filename;
+    }
+
+    filename_t basename, ext;
+    std::tie(basename, ext) = details::file_helper::split_by_extension(filename);
+    return fmt::format(SPDLOG_FILENAME_T("{}.{}{}"), basename, index, ext);
+}
+
+template<typename Mutex>
+SPDLOG_INLINE filename_t rotating_file_sink<Mutex>::filename()
+{
+    std::lock_guard<Mutex> lock(base_sink<Mutex>::mutex_);
+    return file_helper_.filename();
+}
+
+template<typename Mutex>
+SPDLOG_INLINE void rotating_file_sink<Mutex>::sink_it_(const details::log_msg &msg)
+{
+    memory_buf_t formatted;
+    base_sink<Mutex>::formatter_->format(msg, formatted);
+    current_size_ += formatted.size();
+    if (current_size_ > max_size_)
+    {
+        rotate_();
+        current_size_ = formatted.size();
+    }
+    file_helper_.write(formatted);
+}
+
+template<typename Mutex>
+SPDLOG_INLINE void rotating_file_sink<Mutex>::flush_()
+{
+    file_helper_.flush();
+}
+
+// Rotate files:
+// log.txt -> log.1.txt
+// log.1.txt -> log.2.txt
+// log.2.txt -> log.3.txt
+// log.3.txt -> delete
+template<typename Mutex>
+SPDLOG_INLINE void rotating_file_sink<Mutex>::rotate_()
+{
+    using details::os::filename_to_str;
+    using details::os::path_exists;
+    file_helper_.close();
+    for (auto i = max_files_; i > 0; --i)
+    {
+        filename_t src = calc_filename(base_filename_, i - 1);
+        if (!path_exists(src))
+        {
+            continue;
+        }
+        filename_t target = calc_filename(base_filename_, i);
+
+        if (!rename_file_(src, target))
+        {
+            // if failed try again after a small delay.
+            // this is a workaround to a windows issue, where very high rotation
+            // rates can cause the rename to fail with permission denied (because of antivirus?).
+            details::os::sleep_for_millis(100);
+            if (!rename_file_(src, target))
+            {
+                file_helper_.reopen(true); // truncate the log file anyway to prevent it to grow beyond its limit!
+                current_size_ = 0;
+                throw_spdlog_ex("rotating_file_sink: failed renaming " + filename_to_str(src) + " to " + filename_to_str(target), errno);
+            }
+        }
+    }
+    file_helper_.reopen(true);
+}
+
+// delete the target if exists, and rename the src file  to target
+// return true on success, false otherwise.
+template<typename Mutex>
+SPDLOG_INLINE bool rotating_file_sink<Mutex>::rename_file_(const filename_t &src_filename, const filename_t &target_filename)
+{
+    // try to delete the target file in case it already exists.
+    (void)details::os::remove(target_filename);
+    return details::os::rename(src_filename, target_filename) == 0;
+}
+
+} // namespace sinks
+} // namespace spdlog
--- a/src/spdlog/sinks/rotating_file_sink.h
+++ b/src/spdlog/sinks/rotating_file_sink.h
@@ -0,0 +1,78 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include <spdlog/sinks/base_sink.h>
+#include <spdlog/details/file_helper.h>
+#include <spdlog/details/null_mutex.h>
+#include <spdlog/details/synchronous_factory.h>
+
+#include <chrono>
+#include <mutex>
+#include <string>
+
+namespace spdlog {
+namespace sinks {
+
+//
+// Rotating file sink based on size
+//
+template<typename Mutex>
+class rotating_file_sink final : public base_sink<Mutex>
+{
+public:
+    rotating_file_sink(filename_t base_filename, std::size_t max_size, std::size_t max_files, bool rotate_on_open = false);
+    static filename_t calc_filename(const filename_t &filename, std::size_t index);
+    filename_t filename();
+
+protected:
+    void sink_it_(const details::log_msg &msg) override;
+    void flush_() override;
+
+private:
+    // Rotate files:
+    // log.txt -> log.1.txt
+    // log.1.txt -> log.2.txt
+    // log.2.txt -> log.3.txt
+    // log.3.txt -> delete
+    void rotate_();
+
+    // delete the target if exists, and rename the src file  to target
+    // return true on success, false otherwise.
+    bool rename_file_(const filename_t &src_filename, const filename_t &target_filename);
+
+    filename_t base_filename_;
+    std::size_t max_size_;
+    std::size_t max_files_;
+    std::size_t current_size_;
+    details::file_helper file_helper_;
+};
+
+using rotating_file_sink_mt = rotating_file_sink<std::mutex>;
+using rotating_file_sink_st = rotating_file_sink<details::null_mutex>;
+
+} // namespace sinks
+
+//
+// factory functions
+//
+
+template<typename Factory = spdlog::synchronous_factory>
+inline std::shared_ptr<logger> rotating_logger_mt(
+    const std::string &logger_name, const filename_t &filename, size_t max_file_size, size_t max_files, bool rotate_on_open = false)
+{
+    return Factory::template create<sinks::rotating_file_sink_mt>(logger_name, filename, max_file_size, max_files, rotate_on_open);
+}
+
+template<typename Factory = spdlog::synchronous_factory>
+inline std::shared_ptr<logger> rotating_logger_st(
+    const std::string &logger_name, const filename_t &filename, size_t max_file_size, size_t max_files, bool rotate_on_open = false)
+{
+    return Factory::template create<sinks::rotating_file_sink_st>(logger_name, filename, max_file_size, max_files, rotate_on_open);
+}
+} // namespace spdlog
+
+#ifdef SPDLOG_HEADER_ONLY
+#include "rotating_file_sink-inl.h"
+#endif
--- a/src/spdlog/sinks/sink-inl.h
+++ b/src/spdlog/sinks/sink-inl.h
@@ -0,0 +1,25 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#ifndef SPDLOG_HEADER_ONLY
+#include <spdlog/sinks/sink.h>
+#endif
+
+#include <spdlog/common.h>
+
+SPDLOG_INLINE bool spdlog::sinks::sink::should_log(spdlog::level::level_enum msg_level) const
+{
+    return msg_level >= level_.load(std::memory_order_relaxed);
+}
+
+SPDLOG_INLINE void spdlog::sinks::sink::set_level(level::level_enum log_level)
+{
+    level_.store(log_level, std::memory_order_relaxed);
+}
+
+SPDLOG_INLINE spdlog::level::level_enum spdlog::sinks::sink::level() const
+{
+    return static_cast<spdlog::level::level_enum>(level_.load(std::memory_order_relaxed));
+}
--- a/src/spdlog/sinks/sink.h
+++ b/src/spdlog/sinks/sink.h
@@ -0,0 +1,35 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include <spdlog/details/log_msg.h>
+#include <spdlog/formatter.h>
+
+namespace spdlog {
+
+namespace sinks {
+class SPDLOG_API sink
+{
+public:
+    virtual ~sink() = default;
+    virtual void log(const details::log_msg &msg) = 0;
+    virtual void flush() = 0;
+    virtual void set_pattern(const std::string &pattern) = 0;
+    virtual void set_formatter(std::unique_ptr<spdlog::formatter> sink_formatter) = 0;
+
+    void set_level(level::level_enum log_level);
+    level::level_enum level() const;
+    bool should_log(level::level_enum msg_level) const;
+
+protected:
+    // sink log level - default is all
+    level_t level_{level::trace};
+};
+
+} // namespace sinks
+} // namespace spdlog
+
+#ifdef SPDLOG_HEADER_ONLY
+#include "sink-inl.h"
+#endif
--- a/src/spdlog/sinks/stdout_color_sinks-inl.h
+++ b/src/spdlog/sinks/stdout_color_sinks-inl.h
@@ -0,0 +1,38 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#ifndef SPDLOG_HEADER_ONLY
+#include <spdlog/sinks/stdout_color_sinks.h>
+#endif
+
+#include <spdlog/logger.h>
+#include <spdlog/common.h>
+
+namespace spdlog {
+
+template<typename Factory>
+SPDLOG_INLINE std::shared_ptr<logger> stdout_color_mt(const std::string &logger_name, color_mode mode)
+{
+    return Factory::template create<sinks::stdout_color_sink_mt>(logger_name, mode);
+}
+
+template<typename Factory>
+SPDLOG_INLINE std::shared_ptr<logger> stdout_color_st(const std::string &logger_name, color_mode mode)
+{
+    return Factory::template create<sinks::stdout_color_sink_st>(logger_name, mode);
+}
+
+template<typename Factory>
+SPDLOG_INLINE std::shared_ptr<logger> stderr_color_mt(const std::string &logger_name, color_mode mode)
+{
+    return Factory::template create<sinks::stderr_color_sink_mt>(logger_name, mode);
+}
+
+template<typename Factory>
+SPDLOG_INLINE std::shared_ptr<logger> stderr_color_st(const std::string &logger_name, color_mode mode)
+{
+    return Factory::template create<sinks::stderr_color_sink_st>(logger_name, mode);
+}
+} // namespace spdlog
--- a/src/spdlog/sinks/stdout_color_sinks.h
+++ b/src/spdlog/sinks/stdout_color_sinks.h
@@ -0,0 +1,45 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#ifdef _WIN32
+#include <spdlog/sinks/wincolor_sink.h>
+#else
+#include <spdlog/sinks/ansicolor_sink.h>
+#endif
+
+#include <spdlog/details/synchronous_factory.h>
+
+namespace spdlog {
+namespace sinks {
+#ifdef _WIN32
+using stdout_color_sink_mt = wincolor_stdout_sink_mt;
+using stdout_color_sink_st = wincolor_stdout_sink_st;
+using stderr_color_sink_mt = wincolor_stderr_sink_mt;
+using stderr_color_sink_st = wincolor_stderr_sink_st;
+#else
+using stdout_color_sink_mt = ansicolor_stdout_sink_mt;
+using stdout_color_sink_st = ansicolor_stdout_sink_st;
+using stderr_color_sink_mt = ansicolor_stderr_sink_mt;
+using stderr_color_sink_st = ansicolor_stderr_sink_st;
+#endif
+} // namespace sinks
+
+template<typename Factory = spdlog::synchronous_factory>
+std::shared_ptr<logger> stdout_color_mt(const std::string &logger_name, color_mode mode = color_mode::automatic);
+
+template<typename Factory = spdlog::synchronous_factory>
+std::shared_ptr<logger> stdout_color_st(const std::string &logger_name, color_mode mode = color_mode::automatic);
+
+template<typename Factory = spdlog::synchronous_factory>
+std::shared_ptr<logger> stderr_color_mt(const std::string &logger_name, color_mode mode = color_mode::automatic);
+
+template<typename Factory = spdlog::synchronous_factory>
+std::shared_ptr<logger> stderr_color_st(const std::string &logger_name, color_mode mode = color_mode::automatic);
+
+} // namespace spdlog
+
+#ifdef SPDLOG_HEADER_ONLY
+#include "stdout_color_sinks-inl.h"
+#endif
--- a/src/spdlog/sinks/stdout_sinks-inl.h
+++ b/src/spdlog/sinks/stdout_sinks-inl.h
@@ -0,0 +1,94 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#ifndef SPDLOG_HEADER_ONLY
+#include <spdlog/sinks/stdout_sinks.h>
+#endif
+
+#include <spdlog/details/console_globals.h>
+#include <spdlog/pattern_formatter.h>
+#include <memory>
+
+namespace spdlog {
+
+namespace sinks {
+
+template<typename ConsoleMutex>
+SPDLOG_INLINE stdout_sink_base<ConsoleMutex>::stdout_sink_base(FILE *file)
+    : mutex_(ConsoleMutex::mutex())
+    , file_(file)
+    , formatter_(details::make_unique<spdlog::pattern_formatter>())
+{}
+
+template<typename ConsoleMutex>
+SPDLOG_INLINE void stdout_sink_base<ConsoleMutex>::log(const details::log_msg &msg)
+{
+    std::lock_guard<mutex_t> lock(mutex_);
+    memory_buf_t formatted;
+    formatter_->format(msg, formatted);
+    fwrite(formatted.data(), sizeof(char), formatted.size(), file_);
+    fflush(file_); // flush every line to terminal
+}
+
+template<typename ConsoleMutex>
+SPDLOG_INLINE void stdout_sink_base<ConsoleMutex>::flush()
+{
+    std::lock_guard<mutex_t> lock(mutex_);
+    fflush(file_);
+}
+
+template<typename ConsoleMutex>
+SPDLOG_INLINE void stdout_sink_base<ConsoleMutex>::set_pattern(const std::string &pattern)
+{
+    std::lock_guard<mutex_t> lock(mutex_);
+    formatter_ = std::unique_ptr<spdlog::formatter>(new pattern_formatter(pattern));
+}
+
+template<typename ConsoleMutex>
+SPDLOG_INLINE void stdout_sink_base<ConsoleMutex>::set_formatter(std::unique_ptr<spdlog::formatter> sink_formatter)
+{
+    std::lock_guard<mutex_t> lock(mutex_);
+    formatter_ = std::move(sink_formatter);
+}
+
+// stdout sink
+template<typename ConsoleMutex>
+SPDLOG_INLINE stdout_sink<ConsoleMutex>::stdout_sink()
+    : stdout_sink_base<ConsoleMutex>(stdout)
+{}
+
+// stderr sink
+template<typename ConsoleMutex>
+SPDLOG_INLINE stderr_sink<ConsoleMutex>::stderr_sink()
+    : stdout_sink_base<ConsoleMutex>(stderr)
+{}
+
+} // namespace sinks
+
+// factory methods
+template<typename Factory>
+SPDLOG_INLINE std::shared_ptr<logger> stdout_logger_mt(const std::string &logger_name)
+{
+    return Factory::template create<sinks::stdout_sink_mt>(logger_name);
+}
+
+template<typename Factory>
+SPDLOG_INLINE std::shared_ptr<logger> stdout_logger_st(const std::string &logger_name)
+{
+    return Factory::template create<sinks::stdout_sink_st>(logger_name);
+}
+
+template<typename Factory>
+SPDLOG_INLINE std::shared_ptr<logger> stderr_logger_mt(const std::string &logger_name)
+{
+    return Factory::template create<sinks::stderr_sink_mt>(logger_name);
+}
+
+template<typename Factory>
+SPDLOG_INLINE std::shared_ptr<logger> stderr_logger_st(const std::string &logger_name)
+{
+    return Factory::template create<sinks::stderr_sink_st>(logger_name);
+}
+} // namespace spdlog
--- a/src/spdlog/sinks/stdout_sinks.h
+++ b/src/spdlog/sinks/stdout_sinks.h
@@ -0,0 +1,80 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include <spdlog/details/console_globals.h>
+#include <spdlog/details/synchronous_factory.h>
+#include <spdlog/sinks/sink.h>
+#include <cstdio>
+
+namespace spdlog {
+
+namespace sinks {
+
+template<typename ConsoleMutex>
+class stdout_sink_base : public sink
+{
+public:
+    using mutex_t = typename ConsoleMutex::mutex_t;
+    explicit stdout_sink_base(FILE *file);
+    ~stdout_sink_base() override = default;
+
+    stdout_sink_base(const stdout_sink_base &other) = delete;
+    stdout_sink_base(stdout_sink_base &&other) = delete;
+
+    stdout_sink_base &operator=(const stdout_sink_base &other) = delete;
+    stdout_sink_base &operator=(stdout_sink_base &&other) = delete;
+
+    void log(const details::log_msg &msg) override;
+    void flush() override;
+    void set_pattern(const std::string &pattern) override;
+
+    void set_formatter(std::unique_ptr<spdlog::formatter> sink_formatter) override;
+
+protected:
+    mutex_t &mutex_;
+    FILE *file_;
+    std::unique_ptr<spdlog::formatter> formatter_;
+};
+
+template<typename ConsoleMutex>
+class stdout_sink : public stdout_sink_base<ConsoleMutex>
+{
+public:
+    stdout_sink();
+};
+
+template<typename ConsoleMutex>
+class stderr_sink : public stdout_sink_base<ConsoleMutex>
+{
+public:
+    stderr_sink();
+};
+
+using stdout_sink_mt = stdout_sink<details::console_mutex>;
+using stdout_sink_st = stdout_sink<details::console_nullmutex>;
+
+using stderr_sink_mt = stderr_sink<details::console_mutex>;
+using stderr_sink_st = stderr_sink<details::console_nullmutex>;
+
+} // namespace sinks
+
+// factory methods
+template<typename Factory = spdlog::synchronous_factory>
+std::shared_ptr<logger> stdout_logger_mt(const std::string &logger_name);
+
+template<typename Factory = spdlog::synchronous_factory>
+std::shared_ptr<logger> stdout_logger_st(const std::string &logger_name);
+
+template<typename Factory = spdlog::synchronous_factory>
+std::shared_ptr<logger> stderr_logger_mt(const std::string &logger_name);
+
+template<typename Factory = spdlog::synchronous_factory>
+std::shared_ptr<logger> stderr_logger_st(const std::string &logger_name);
+
+} // namespace spdlog
+
+#ifdef SPDLOG_HEADER_ONLY
+#include "stdout_sinks-inl.h"
+#endif
--- a/src/spdlog/sinks/syslog_sink.h
+++ b/src/spdlog/sinks/syslog_sink.h
@@ -0,0 +1,109 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include <spdlog/sinks/base_sink.h>
+#include <spdlog/details/null_mutex.h>
+#include <spdlog/details/synchronous_factory.h>
+
+#include <array>
+#include <string>
+#include <syslog.h>
+
+namespace spdlog {
+namespace sinks {
+/**
+ * Sink that write to syslog using the `syscall()` library call.
+ */
+template<typename Mutex>
+class syslog_sink : public base_sink<Mutex>
+{
+
+public:
+    syslog_sink(std::string ident, int syslog_option, int syslog_facility, bool enable_formatting)
+        : enable_formatting_{enable_formatting}
+        , syslog_levels_{{/* spdlog::level::trace      */ LOG_DEBUG,
+              /* spdlog::level::debug      */ LOG_DEBUG,
+              /* spdlog::level::info       */ LOG_INFO,
+              /* spdlog::level::warn       */ LOG_WARNING,
+              /* spdlog::level::err        */ LOG_ERR,
+              /* spdlog::level::critical   */ LOG_CRIT,
+              /* spdlog::level::off        */ LOG_INFO}}
+        , ident_{std::move(ident)}
+    {
+        // set ident to be program name if empty
+        ::openlog(ident_.empty() ? nullptr : ident_.c_str(), syslog_option, syslog_facility);
+    }
+
+    ~syslog_sink() override
+    {
+        ::closelog();
+    }
+
+    syslog_sink(const syslog_sink &) = delete;
+    syslog_sink &operator=(const syslog_sink &) = delete;
+
+protected:
+    void sink_it_(const details::log_msg &msg) override
+    {
+        string_view_t payload;
+        memory_buf_t formatted;
+        if (enable_formatting_)
+        {
+            base_sink<Mutex>::formatter_->format(msg, formatted);
+            payload = string_view_t(formatted.data(), formatted.size());
+        }
+        else
+        {
+            payload = msg.payload;
+        }
+
+        size_t length = payload.size();
+        // limit to max int
+        if (length > static_cast<size_t>(std::numeric_limits<int>::max()))
+        {
+            length = static_cast<size_t>(std::numeric_limits<int>::max());
+        }
+
+        ::syslog(syslog_prio_from_level(msg), "%.*s", static_cast<int>(length), payload.data());
+    }
+
+    void flush_() override {}
+    bool enable_formatting_ = false;
+
+private:
+    using levels_array = std::array<int, 7>;
+    levels_array syslog_levels_;
+    // must store the ident because the man says openlog might use the pointer as
+    // is and not a string copy
+    const std::string ident_;
+
+    //
+    // Simply maps spdlog's log level to syslog priority level.
+    //
+    int syslog_prio_from_level(const details::log_msg &msg) const
+    {
+        return syslog_levels_.at(static_cast<levels_array::size_type>(msg.level));
+    }
+};
+
+using syslog_sink_mt = syslog_sink<std::mutex>;
+using syslog_sink_st = syslog_sink<details::null_mutex>;
+} // namespace sinks
+
+// Create and register a syslog logger
+template<typename Factory = spdlog::synchronous_factory>
+inline std::shared_ptr<logger> syslog_logger_mt(const std::string &logger_name, const std::string &syslog_ident = "", int syslog_option = 0,
+    int syslog_facility = LOG_USER, bool enable_formatting = false)
+{
+    return Factory::template create<sinks::syslog_sink_mt>(logger_name, syslog_ident, syslog_option, syslog_facility, enable_formatting);
+}
+
+template<typename Factory = spdlog::synchronous_factory>
+inline std::shared_ptr<logger> syslog_logger_st(const std::string &logger_name, const std::string &syslog_ident = "", int syslog_option = 0,
+    int syslog_facility = LOG_USER, bool enable_formatting = false)
+{
+    return Factory::template create<sinks::syslog_sink_st>(logger_name, syslog_ident, syslog_option, syslog_facility, enable_formatting);
+}
+} // namespace spdlog
--- a/src/spdlog/sinks/systemd_sink.h
+++ b/src/spdlog/sinks/systemd_sink.h
@@ -0,0 +1,103 @@
+// Copyright(c) 2019 ZVYAGIN.Alexander@gmail.com
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include <spdlog/sinks/base_sink.h>
+#include <spdlog/details/null_mutex.h>
+#include <spdlog/details/synchronous_factory.h>
+
+#include <array>
+#ifndef SD_JOURNAL_SUPPRESS_LOCATION
+#define SD_JOURNAL_SUPPRESS_LOCATION
+#endif
+#include <systemd/sd-journal.h>
+
+namespace spdlog {
+namespace sinks {
+
+/**
+ * Sink that write to systemd journal using the `sd_journal_send()` library call.
+ *
+ * Locking is not needed, as `sd_journal_send()` itself is thread-safe.
+ */
+template<typename Mutex>
+class systemd_sink : public base_sink<Mutex>
+{
+public:
+    //
+    systemd_sink()
+        : syslog_levels_{{/* spdlog::level::trace      */ LOG_DEBUG,
+              /* spdlog::level::debug      */ LOG_DEBUG,
+              /* spdlog::level::info       */ LOG_INFO,
+              /* spdlog::level::warn       */ LOG_WARNING,
+              /* spdlog::level::err        */ LOG_ERR,
+              /* spdlog::level::critical   */ LOG_CRIT,
+              /* spdlog::level::off        */ LOG_INFO}}
+    {}
+
+    ~systemd_sink() override {}
+
+    systemd_sink(const systemd_sink &) = delete;
+    systemd_sink &operator=(const systemd_sink &) = delete;
+
+protected:
+    using levels_array = std::array<int, 7>;
+    levels_array syslog_levels_;
+
+    void sink_it_(const details::log_msg &msg) override
+    {
+        int err;
+
+        size_t length = msg.payload.size();
+        // limit to max int
+        if (length > static_cast<size_t>(std::numeric_limits<int>::max()))
+        {
+            length = static_cast<size_t>(std::numeric_limits<int>::max());
+        }
+
+        // Do not send source location if not available
+        if (msg.source.empty())
+        {
+            // Note: function call inside '()' to avoid macro expansion
+            err = (sd_journal_send)("MESSAGE=%.*s", static_cast<int>(length), msg.payload.data(), "PRIORITY=%d", syslog_level(msg.level),
+                "SYSLOG_IDENTIFIER=%.*s", static_cast<int>(msg.logger_name.size()), msg.logger_name.data(), nullptr);
+        }
+        else
+        {
+            err = (sd_journal_send)("MESSAGE=%.*s", static_cast<int>(length), msg.payload.data(), "PRIORITY=%d", syslog_level(msg.level),
+                "SYSLOG_IDENTIFIER=%.*s", static_cast<int>(msg.logger_name.size()), msg.logger_name.data(), "CODE_FILE=%s",
+                msg.source.filename, "CODE_LINE=%d", msg.source.line, "CODE_FUNC=%s", msg.source.funcname, nullptr);
+        }
+
+        if (err)
+        {
+            throw_spdlog_ex("Failed writing to systemd", errno);
+        }
+    }
+
+    int syslog_level(level::level_enum l)
+    {
+        return syslog_levels_.at(static_cast<levels_array::size_type>(l));
+    }
+
+    void flush_() override {}
+};
+
+using systemd_sink_mt = systemd_sink<std::mutex>;
+using systemd_sink_st = systemd_sink<details::null_mutex>;
+} // namespace sinks
+
+// Create and register a syslog logger
+template<typename Factory = spdlog::synchronous_factory>
+inline std::shared_ptr<logger> systemd_logger_mt(const std::string &logger_name)
+{
+    return Factory::template create<sinks::systemd_sink_mt>(logger_name);
+}
+
+template<typename Factory = spdlog::synchronous_factory>
+inline std::shared_ptr<logger> systemd_logger_st(const std::string &logger_name)
+{
+    return Factory::template create<sinks::systemd_sink_st>(logger_name);
+}
+} // namespace spdlog
--- a/src/spdlog/sinks/tcp_sink.h
+++ b/src/spdlog/sinks/tcp_sink.h
@@ -0,0 +1,81 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include <spdlog/common.h>
+#include <spdlog/sinks/base_sink.h>
+#include <spdlog/details/null_mutex.h>
+#ifdef _WIN32
+#include <spdlog/details/tcp_client-windows.h>
+#else
+#include <spdlog/details/tcp_client.h>
+#endif
+
+#include <mutex>
+#include <string>
+#include <chrono>
+#include <functional>
+
+#pragma once
+
+// Simple tcp client sink
+// Connects to remote address and send the formatted log.
+// Will attempt to reconnect if connection drops.
+// If more complicated behaviour is needed (i.e get responses), you can inherit it and override the sink_it_ method.
+
+namespace spdlog {
+namespace sinks {
+
+struct tcp_sink_config
+{
+    std::string server_host;
+    int server_port;
+    bool lazy_connect = false; // if true connect on first log call instead of on construction
+
+    tcp_sink_config(std::string host, int port)
+        : server_host{std::move(host)}
+        , server_port{port}
+    {}
+};
+
+template<typename Mutex>
+class tcp_sink : public spdlog::sinks::base_sink<Mutex>
+{
+public:
+    // connect to tcp host/port or throw if failed
+    // host can be hostname or ip address
+
+    explicit tcp_sink(tcp_sink_config sink_config)
+        : config_{std::move(sink_config)}
+    {
+        if (!config_.lazy_connect)
+        {
+            this->client_.connect(config_.server_host, config_.server_port);
+        }
+    }
+
+    ~tcp_sink() override = default;
+
+protected:
+    void sink_it_(const spdlog::details::log_msg &msg) override
+    {
+        spdlog::memory_buf_t formatted;
+        spdlog::sinks::base_sink<Mutex>::formatter_->format(msg, formatted);
+        if (!client_.is_connected())
+        {
+            client_.connect(config_.server_host, config_.server_port);
+        }
+        client_.send(formatted.data(), formatted.size());
+    }
+
+    void flush_() override {}
+    tcp_sink_config config_;
+    details::tcp_client client_;
+};
+
+using tcp_sink_mt = tcp_sink<std::mutex>;
+using tcp_sink_st = tcp_sink<spdlog::details::null_mutex>;
+
+} // namespace sinks
+} // namespace spdlog
--- a/src/spdlog/sinks/win_eventlog_sink.h
+++ b/src/spdlog/sinks/win_eventlog_sink.h
@@ -0,0 +1,266 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+// Writing to Windows Event Log requires the registry entries below to be present, with the following modifications:
+// 1. <log_name>    should be replaced with your log name (e.g. your application name)
+// 2. <source_name> should be replaced with the specific source name and the key should be duplicated for
+//                  each source used in the application
+//
+// Since typically modifications of this kind require elevation, it's better to do it as a part of setup procedure.
+// The snippet below uses mscoree.dll as the message file as it exists on most of the Windows systems anyway and
+// happens to contain the needed resource.
+//
+// You can also specify a custom message file if needed.
+// Please refer to Event Log functions descriptions in MSDN for more details on custom message files.
+
+/*---------------------------------------------------------------------------------------
+
+Windows Registry Editor Version 5.00
+
+[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\EventLog\<log_name>]
+
+[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\EventLog\<log_name>\<source_name>]
+"TypesSupported"=dword:00000007
+"EventMessageFile"=hex(2):25,00,73,00,79,00,73,00,74,00,65,00,6d,00,72,00,6f,\
+  00,6f,00,74,00,25,00,5c,00,53,00,79,00,73,00,74,00,65,00,6d,00,33,00,32,00,\
+  5c,00,6d,00,73,00,63,00,6f,00,72,00,65,00,65,00,2e,00,64,00,6c,00,6c,00,00,\
+  00
+
+-----------------------------------------------------------------------------------------*/
+
+#pragma once
+
+#include <spdlog/details/null_mutex.h>
+#include <spdlog/sinks/base_sink.h>
+
+#include <spdlog/details/windows_include.h>
+#include <winbase.h>
+
+#include <mutex>
+#include <string>
+#include <vector>
+
+namespace spdlog {
+namespace sinks {
+
+namespace win_eventlog {
+
+namespace internal {
+
+/** Windows error */
+struct win32_error : public spdlog_ex
+{
+    /** Formats an error report line: "user-message: error-code (system message)" */
+    static std::string format(std::string const &user_message, DWORD error_code = GetLastError())
+    {
+        std::string system_message;
+
+        LPSTR format_message_result{};
+        auto format_message_succeeded =
+            ::FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, nullptr,
+                error_code, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), (LPSTR)&format_message_result, 0, nullptr);
+
+        if (format_message_succeeded && format_message_result)
+        {
+            system_message = fmt::format(" ({})", format_message_result);
+        }
+
+        if (format_message_result)
+        {
+            LocalFree((HLOCAL)format_message_result);
+        }
+
+        return fmt::format("{}: {}{}", user_message, error_code, system_message);
+    }
+
+    explicit win32_error(std::string const &func_name, DWORD error = GetLastError())
+        : spdlog_ex(format(func_name, error))
+    {}
+};
+
+/** Wrapper for security identifiers (SID) on Windows */
+struct sid_t
+{
+    std::vector<char> buffer_;
+
+public:
+    sid_t() {}
+
+    /** creates a wrapped SID copy */
+    static sid_t duplicate_sid(PSID psid)
+    {
+        if (!::IsValidSid(psid))
+        {
+            throw_spdlog_ex("sid_t::sid_t(): invalid SID received");
+        }
+
+        auto const sid_length{::GetLengthSid(psid)};
+
+        sid_t result;
+        result.buffer_.resize(sid_length);
+        if (!::CopySid(sid_length, (PSID)result.as_sid(), psid))
+        {
+            SPDLOG_THROW(win32_error("CopySid"));
+        }
+
+        return result;
+    }
+
+    /** Retrieves pointer to the internal buffer contents as SID* */
+    SID *as_sid() const
+    {
+        return buffer_.empty() ? nullptr : (SID *)buffer_.data();
+    }
+
+    /** Get SID for the current user */
+    static sid_t get_current_user_sid()
+    {
+        /* create and init RAII holder for process token */
+        struct process_token_t
+        {
+            HANDLE token_handle_ = INVALID_HANDLE_VALUE;
+            explicit process_token_t(HANDLE process)
+            {
+                if (!::OpenProcessToken(process, TOKEN_QUERY, &token_handle_))
+                {
+                    SPDLOG_THROW(win32_error("OpenProcessToken"));
+                }
+            }
+
+            ~process_token_t()
+            {
+                ::CloseHandle(token_handle_);
+            }
+
+        } current_process_token(::GetCurrentProcess()); // GetCurrentProcess returns pseudohandle, no leak here!
+
+        // Get the required size, this is expected to fail with ERROR_INSUFFICIENT_BUFFER and return the token size
+        DWORD tusize = 0;
+        if (::GetTokenInformation(current_process_token.token_handle_, TokenUser, NULL, 0, &tusize))
+        {
+            SPDLOG_THROW(win32_error("GetTokenInformation should fail"));
+        }
+
+        // get user token
+        std::vector<unsigned char> buffer(static_cast<size_t>(tusize));
+        if (!::GetTokenInformation(current_process_token.token_handle_, TokenUser, (LPVOID)buffer.data(), tusize, &tusize))
+        {
+            SPDLOG_THROW(win32_error("GetTokenInformation"));
+        }
+
+        // create a wrapper of the SID data as stored in the user token
+        return sid_t::duplicate_sid(((TOKEN_USER *)buffer.data())->User.Sid);
+    }
+};
+
+struct eventlog
+{
+    static WORD get_event_type(details::log_msg const &msg)
+    {
+        switch (msg.level)
+        {
+        case level::trace:
+        case level::debug:
+            return EVENTLOG_SUCCESS;
+
+        case level::info:
+            return EVENTLOG_INFORMATION_TYPE;
+
+        case level::warn:
+            return EVENTLOG_WARNING_TYPE;
+
+        case level::err:
+        case level::critical:
+        case level::off:
+            return EVENTLOG_ERROR_TYPE;
+
+        default:
+            return EVENTLOG_INFORMATION_TYPE;
+        }
+    }
+
+    static WORD get_event_category(details::log_msg const &msg)
+    {
+        return (WORD)msg.level;
+    }
+};
+
+} // namespace internal
+
+/*
+ * Windows Event Log sink
+ */
+template<typename Mutex>
+class win_eventlog_sink : public base_sink<Mutex>
+{
+private:
+    HANDLE hEventLog_{NULL};
+    internal::sid_t current_user_sid_;
+    std::string source_;
+    WORD event_id_;
+
+    HANDLE event_log_handle()
+    {
+        if (!hEventLog_)
+        {
+            hEventLog_ = ::RegisterEventSource(nullptr, source_.c_str());
+            if (!hEventLog_ || hEventLog_ == (HANDLE)ERROR_ACCESS_DENIED)
+            {
+                SPDLOG_THROW(internal::win32_error("RegisterEventSource"));
+            }
+        }
+
+        return hEventLog_;
+    }
+
+protected:
+    void sink_it_(const details::log_msg &msg) override
+    {
+        using namespace internal;
+
+        memory_buf_t formatted;
+        base_sink<Mutex>::formatter_->format(msg, formatted);
+        formatted.push_back('\0');
+        LPCSTR lp_str = static_cast<LPCSTR>(formatted.data());
+
+        auto succeeded = ::ReportEvent(event_log_handle(), eventlog::get_event_type(msg), eventlog::get_event_category(msg), event_id_,
+            current_user_sid_.as_sid(), 1, 0, &lp_str, nullptr);
+
+        if (!succeeded)
+        {
+            SPDLOG_THROW(win32_error("ReportEvent"));
+        }
+    }
+
+    void flush_() override {}
+
+public:
+    win_eventlog_sink(std::string const &source, WORD event_id = 1000 /* according to mscoree.dll */)
+        : source_(source)
+        , event_id_(event_id)
+    {
+        try
+        {
+            current_user_sid_ = internal::sid_t::get_current_user_sid();
+        }
+        catch (...)
+        {
+            // get_current_user_sid() is unlikely to fail and if it does, we can still proceed without
+            // current_user_sid but in the event log the record will have no user name
+        }
+    }
+
+    ~win_eventlog_sink()
+    {
+        if (hEventLog_)
+            DeregisterEventSource(hEventLog_);
+    }
+};
+
+} // namespace win_eventlog
+
+using win_eventlog_sink_mt = win_eventlog::win_eventlog_sink<std::mutex>;
+using win_eventlog_sink_st = win_eventlog::win_eventlog_sink<details::null_mutex>;
+
+} // namespace sinks
+} // namespace spdlog
--- a/src/spdlog/sinks/wincolor_sink-inl.h
+++ b/src/spdlog/sinks/wincolor_sink-inl.h
@@ -0,0 +1,180 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#ifndef SPDLOG_HEADER_ONLY
+#include <spdlog/sinks/wincolor_sink.h>
+#endif
+
+#include <spdlog/common.h>
+#include <spdlog/pattern_formatter.h>
+
+namespace spdlog {
+namespace sinks {
+
+template<typename ConsoleMutex>
+SPDLOG_INLINE wincolor_sink<ConsoleMutex>::wincolor_sink(HANDLE out_handle, color_mode mode)
+    : out_handle_(out_handle)
+    , mutex_(ConsoleMutex::mutex())
+    , formatter_(details::make_unique<spdlog::pattern_formatter>())
+{
+    // check if out_handle is points to the actual console.
+    // ::GetConsoleMode() should return 0 if it is redirected or not valid console handle.
+    DWORD console_mode;
+    in_console_ = ::GetConsoleMode(out_handle, &console_mode) != 0;
+
+    set_color_mode(mode);
+    colors_[level::trace] = WHITE;
+    colors_[level::debug] = CYAN;
+    colors_[level::info] = GREEN;
+    colors_[level::warn] = YELLOW | BOLD;
+    colors_[level::err] = RED | BOLD;                         // red bold
+    colors_[level::critical] = BACKGROUND_RED | WHITE | BOLD; // white bold on red background
+    colors_[level::off] = 0;
+}
+
+template<typename ConsoleMutex>
+SPDLOG_INLINE wincolor_sink<ConsoleMutex>::~wincolor_sink()
+{
+    this->flush();
+}
+
+// change the color for the given level
+template<typename ConsoleMutex>
+void SPDLOG_INLINE wincolor_sink<ConsoleMutex>::set_color(level::level_enum level, WORD color)
+{
+    std::lock_guard<mutex_t> lock(mutex_);
+    colors_[level] = color;
+}
+
+template<typename ConsoleMutex>
+void SPDLOG_INLINE wincolor_sink<ConsoleMutex>::log(const details::log_msg &msg)
+{
+    std::lock_guard<mutex_t> lock(mutex_);
+    msg.color_range_start = 0;
+    msg.color_range_end = 0;
+    memory_buf_t formatted;
+    formatter_->format(msg, formatted);
+    if (!in_console_)
+    {
+        write_to_file_(formatted);
+        return;
+    }
+    if (should_do_colors_ && msg.color_range_end > msg.color_range_start)
+    {
+        // before color range
+        print_range_(formatted, 0, msg.color_range_start);
+
+        // in color range
+        auto orig_attribs = set_foreground_color_(colors_[msg.level]);
+        print_range_(formatted, msg.color_range_start, msg.color_range_end);
+        // reset to orig colors
+        ::SetConsoleTextAttribute(out_handle_, orig_attribs);
+        print_range_(formatted, msg.color_range_end, formatted.size());
+    }
+    else // print without colors if color range is invalid (or color is disabled)
+    {
+        print_range_(formatted, 0, formatted.size());
+    }
+}
+
+template<typename ConsoleMutex>
+void SPDLOG_INLINE wincolor_sink<ConsoleMutex>::flush()
+{
+    // windows console always flushed?
+}
+
+template<typename ConsoleMutex>
+void SPDLOG_INLINE wincolor_sink<ConsoleMutex>::set_pattern(const std::string &pattern)
+{
+    std::lock_guard<mutex_t> lock(mutex_);
+    formatter_ = std::unique_ptr<spdlog::formatter>(new pattern_formatter(pattern));
+}
+
+template<typename ConsoleMutex>
+void SPDLOG_INLINE wincolor_sink<ConsoleMutex>::set_formatter(std::unique_ptr<spdlog::formatter> sink_formatter)
+{
+    std::lock_guard<mutex_t> lock(mutex_);
+    formatter_ = std::move(sink_formatter);
+}
+
+template<typename ConsoleMutex>
+void SPDLOG_INLINE wincolor_sink<ConsoleMutex>::set_color_mode(color_mode mode)
+{
+    switch (mode)
+    {
+    case color_mode::always:
+    case color_mode::automatic:
+        should_do_colors_ = true;
+        break;
+    case color_mode::never:
+        should_do_colors_ = false;
+        break;
+    default:
+        should_do_colors_ = true;
+    }
+}
+
+// set foreground color and return the orig console attributes (for resetting later)
+template<typename ConsoleMutex>
+WORD SPDLOG_INLINE wincolor_sink<ConsoleMutex>::set_foreground_color_(WORD attribs)
+{
+    CONSOLE_SCREEN_BUFFER_INFO orig_buffer_info;
+    ::GetConsoleScreenBufferInfo(out_handle_, &orig_buffer_info);
+    WORD back_color = orig_buffer_info.wAttributes;
+    // retrieve the current background color
+    back_color &= static_cast<WORD>(~(FOREGROUND_RED | FOREGROUND_GREEN | FOREGROUND_BLUE | FOREGROUND_INTENSITY));
+    // keep the background color unchanged
+    ::SetConsoleTextAttribute(out_handle_, attribs | back_color);
+    return orig_buffer_info.wAttributes; // return orig attribs
+}
+
+// print a range of formatted message to console
+template<typename ConsoleMutex>
+void SPDLOG_INLINE wincolor_sink<ConsoleMutex>::print_range_(const memory_buf_t &formatted, size_t start, size_t end)
+{
+    auto size = static_cast<DWORD>(end - start);
+    ::WriteConsoleA(out_handle_, formatted.data() + start, size, nullptr, nullptr);
+}
+
+template<typename ConsoleMutex>
+void SPDLOG_INLINE wincolor_sink<ConsoleMutex>::write_to_file_(const memory_buf_t &formatted)
+{
+    if (out_handle_ == nullptr) // no console and no file redirect
+    {
+        return;
+    }
+    auto size = static_cast<DWORD>(formatted.size());
+    if (size == 0)
+    {
+        return;
+    }
+
+    DWORD total_written = 0;
+    do
+    {
+        DWORD bytes_written = 0;
+        bool ok = ::WriteFile(out_handle_, formatted.data() + total_written, size - total_written, &bytes_written, nullptr) != 0;
+        if (!ok || bytes_written == 0)
+        {
+            throw_spdlog_ex("wincolor_sink: write_to_file_ failed. GetLastError(): " + std::to_string(::GetLastError()));
+        }
+        total_written += bytes_written;
+    } while (total_written < size);
+}
+
+// wincolor_stdout_sink
+template<typename ConsoleMutex>
+SPDLOG_INLINE wincolor_stdout_sink<ConsoleMutex>::wincolor_stdout_sink(color_mode mode)
+    : wincolor_sink<ConsoleMutex>(::GetStdHandle(STD_OUTPUT_HANDLE), mode)
+{}
+
+// wincolor_stderr_sink
+template<typename ConsoleMutex>
+SPDLOG_INLINE wincolor_stderr_sink<ConsoleMutex>::wincolor_stderr_sink(color_mode mode)
+    : wincolor_sink<ConsoleMutex>(::GetStdHandle(STD_ERROR_HANDLE), mode)
+{}
+
+} // namespace sinks
+} // namespace spdlog
--- a/src/spdlog/sinks/wincolor_sink.h
+++ b/src/spdlog/sinks/wincolor_sink.h
@@ -0,0 +1,94 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include <spdlog/common.h>
+#include <spdlog/details/console_globals.h>
+#include <spdlog/details/null_mutex.h>
+#include <spdlog/sinks/sink.h>
+
+#include <memory>
+#include <mutex>
+#include <string>
+#include <array>
+
+#include <spdlog/details/windows_include.h>
+#include <wincon.h>
+
+namespace spdlog {
+namespace sinks {
+/*
+ * Windows color console sink. Uses WriteConsoleA to write to the console with
+ * colors
+ */
+template<typename ConsoleMutex>
+class wincolor_sink : public sink
+{
+public:
+    const WORD BOLD = FOREGROUND_INTENSITY;
+    const WORD RED = FOREGROUND_RED;
+    const WORD GREEN = FOREGROUND_GREEN;
+    const WORD CYAN = FOREGROUND_GREEN | FOREGROUND_BLUE;
+    const WORD WHITE = FOREGROUND_RED | FOREGROUND_GREEN | FOREGROUND_BLUE;
+    const WORD YELLOW = FOREGROUND_RED | FOREGROUND_GREEN;
+
+    wincolor_sink(HANDLE out_handle, color_mode mode);
+    ~wincolor_sink() override;
+
+    wincolor_sink(const wincolor_sink &other) = delete;
+    wincolor_sink &operator=(const wincolor_sink &other) = delete;
+
+    // change the color for the given level
+    void set_color(level::level_enum level, WORD color);
+    void log(const details::log_msg &msg) final override;
+    void flush() final override;
+    void set_pattern(const std::string &pattern) override final;
+    void set_formatter(std::unique_ptr<spdlog::formatter> sink_formatter) override final;
+    void set_color_mode(color_mode mode);
+
+protected:
+    using mutex_t = typename ConsoleMutex::mutex_t;
+    HANDLE out_handle_;
+    mutex_t &mutex_;
+    bool in_console_;
+    bool should_do_colors_;
+    std::unique_ptr<spdlog::formatter> formatter_;
+    std::array<WORD, level::n_levels> colors_;
+
+    // set foreground color and return the orig console attributes (for resetting later)
+    WORD set_foreground_color_(WORD attribs);
+
+    // print a range of formatted message to console
+    void print_range_(const memory_buf_t &formatted, size_t start, size_t end);
+
+    // in case we are redirected to file (not in console mode)
+    void write_to_file_(const memory_buf_t &formatted);
+};
+
+template<typename ConsoleMutex>
+class wincolor_stdout_sink : public wincolor_sink<ConsoleMutex>
+{
+public:
+    explicit wincolor_stdout_sink(color_mode mode = color_mode::automatic);
+};
+
+template<typename ConsoleMutex>
+class wincolor_stderr_sink : public wincolor_sink<ConsoleMutex>
+{
+public:
+    explicit wincolor_stderr_sink(color_mode mode = color_mode::automatic);
+};
+
+using wincolor_stdout_sink_mt = wincolor_stdout_sink<details::console_mutex>;
+using wincolor_stdout_sink_st = wincolor_stdout_sink<details::console_nullmutex>;
+
+using wincolor_stderr_sink_mt = wincolor_stderr_sink<details::console_mutex>;
+using wincolor_stderr_sink_st = wincolor_stderr_sink<details::console_nullmutex>;
+
+} // namespace sinks
+} // namespace spdlog
+
+#ifdef SPDLOG_HEADER_ONLY
+#include "wincolor_sink-inl.h"
+#endif
--- a/Show More
+++ b/Show More
Author	SHA1	Message	Date
Ryzerth	a9c82ecc81	Band plans alpha	2020-08-05 21:13:53 +02:00
Ryzerth	3aa8ce80db	Adding credits to readme 2	2020-08-05 14:06:31 +02:00
Ryzerth	294337aa63	Adding credits to readme 2	2020-08-05 13:12:30 +02:00
Ryzerth	908abf0743	Adding credits to readme 2	2020-08-05 13:11:42 +02:00
Ryzerth	509e4aa7f7	Adding credits to readme 2	2020-08-05 13:07:12 +02:00
Ryzerth	13fbd6a800	Adding credits to readme 2	2020-08-05 13:04:46 +02:00
Ryzerth	b430f88245	Adding credits to readme	2020-08-05 13:00:32 +02:00
Ryzerth	e24e3cbc2a	more fixes	2020-08-05 12:50:34 +02:00
Ryzerth	08292c279e	Bandplan system on new branch	2020-08-05 11:23:13 +02:00
Ryzerth	10f1b992dd	Bandplan system fix	2020-08-05 11:17:47 +02:00
Ryzerth	022898c61d	Bandplan system	2020-08-04 21:34:56 +02:00
Ryzerth	cd7e5cf1bc	Oops, forgot to push before leaving	2020-08-04 14:19:41 +02:00
Ryzerth	f5d6e609d7	Fixed slow waterfall with low sample rates	2020-07-21 01:58:47 +02:00
Ryzerth	ed49ad6f7f	Fixed humming noise	2020-07-20 20:22:13 +02:00