New hashing algorithm

This commit is contained in:
ProfessionalUwU 2023-06-29 19:53:00 +02:00
parent f9cdac5f92
commit f65108425c
Signed by: ProfessionalUwU
GPG Key ID: 9F28CB1645C4BFB5
2 changed files with 39 additions and 5 deletions

View File

@ -18,6 +18,7 @@
<ItemGroup>
<PackageReference Include="Microsoft.Data.Sqlite" Version="7.0.8" />
<PackageReference Include="MurmurHash.Net" Version="0.0.2" />
<PackageReference Include="Serilog" Version="3.0.1" />
<PackageReference Include="Serilog.Sinks.Console" Version="4.1.0" />
<PackageReference Include="Serilog.Sinks.File" Version="5.0.0" />

View File

@ -4,6 +4,7 @@ using System.Security.Cryptography;
using Microsoft.Data.Sqlite;
using Serilog;
using Serilog.Events;
using MurmurHash.Net;
namespace Chksum.Utils;
public class ChksumUtils {
@ -107,6 +108,38 @@ public class ChksumUtils {
return new Dictionary<string, string>(checksums);
}
private Dictionary<string, uint> CalculateChecksumsWithMurmur(string[] filenames) {
ConcurrentDictionary<string, uint> checksums = new ConcurrentDictionary<string, uint>();
Parallel.ForEach(filenames, (filename, state) => {
using (var stream = File.OpenRead(filename)) {
var hash = CalculateMurmurHash32(stream);
lock (checksums) {
checksums.TryAdd(filename, hash);
}
}
});
logger.Debug("All files were checksummed");
return new Dictionary<string, uint>(checksums);
}
private uint CalculateMurmurHash32(Stream stream) {
const int bufferSize = 4096; // Adjust the buffer size as needed
const uint seed = 123456U; // Adjust the seed value as needed
var buffer = new byte[bufferSize];
uint hash = seed;
int bytesRead;
while ((bytesRead = stream.Read(buffer, 0, bufferSize)) > 0) {
hash = MurmurHash3.Hash32(buffer, seed: 123456U);
}
return hash;
}
public void doTheThing() {
using (var connection = new SqliteConnection("Data Source=" + DatabaseRoot + "chksum.db;Mode=ReadWrite")) {
if (getTotalFileCount() < 1) {
@ -114,13 +147,13 @@ public class ChksumUtils {
return;
}
connection.Open();
Dictionary<string, string> fileHashes = CalculateChecksums(indexFiles());
Dictionary<string, uint> fileHashes = CalculateChecksumsWithMurmur(indexFiles());
foreach (var file in fileHashes) {
string absolutePathToFile = file.Key;
string fileName = Path.GetFileName(absolutePathToFile);
string pathToFile = Path.GetRelativePath(DatabaseRoot, absolutePathToFile);
string fileHash = file.Value;
var fileHash = file.Value;
if (checkIfFileMovedAndUpdatePathToFile(fileHash, fileName, pathToFile) == false && checkIfFileAlreadyExistsInDatabase(fileHash, fileName) == false) {
var command = connection.CreateCommand();
@ -140,7 +173,7 @@ public class ChksumUtils {
}
}
private bool checkIfFileAlreadyExistsInDatabase(string fileHash, string pathToFile) {
private bool checkIfFileAlreadyExistsInDatabase(uint fileHash, string pathToFile) {
string filehash = string.Empty;
string pathtofile = string.Empty;
bool doesExist = false;
@ -164,14 +197,14 @@ public class ChksumUtils {
logger.Verbose("{pathToFile} with the hash {fileHash} was successfully loaded", pathToFile, fileHash);
}
if (fileHash == filehash) {
if (fileHash.ToString() == filehash) {
logger.Verbose("File with filehash {filehash} already exists in the database", filehash);
doesExist = true;
}
return doesExist;
}
private bool checkIfFileMovedAndUpdatePathToFile(string fileHash, string fileName, string pathToFile) {
private bool checkIfFileMovedAndUpdatePathToFile(uint fileHash, string fileName, string pathToFile) {
string pathtofile = string.Empty;
bool wasMoved = false;