Add option --set-vendor

README.md

@@ -65,6 +65,7 @@ Documentation
       --output-cover FILE           extract and save the cover art, if any
       --set-cover FILE              sets the cover art
       --vendor                      print the vendor string
+      --set-vendor VALUE            set the vendor string
       --raw                         disable encoding conversion
 
 See the man page, `opustags.1`, for extensive documentation.

opustags.1

@@ -125,6 +125,10 @@ the front cover really matters. opustags can currently only handle one front cov
 Print the vendor string from the OpusTags packet and do nothing else. Standard tags operations are
 not supported when specifying this flag.
 .TP
+.B \-\-set-vendor \fIVALUE\fP
+Replace the vendor string by the specified value. This action can be performed alongside tag
+edition.
+.TP
 .B \-\-raw
 OpusTags metadata should always be encoded in UTF-8, as per RFC 7845. However, some files may be
 corrupted or possibly even contain intentional binary data. In that case, --raw lets you edit that

src/cli.cc

@@ -39,6 +39,7 @@ Options:
   --output-cover FILE           extract and save the cover art, if any
   --set-cover FILE              sets the cover art
   --vendor                      print the vendor string
+  --set-vendor VALUE            set the vendor string
   --raw                         disable encoding conversion
 
 See the man page for extensive documentation.
@@ -58,6 +59,7 @@ static struct option getopt_options[] = {
 	{"output-cover", required_argument, 0, 'c'},
 	{"set-cover", required_argument, 0, 'C'},
 	{"vendor", no_argument, 0, 'v'},
+	{"set-vendor", required_argument, 0, 'V'},
 	{"raw", no_argument, 0, 'r'},
 	{NULL, 0, 0, 0}
 };
@@ -71,6 +73,7 @@ ot::options ot::parse_options(int argc, char** argv, FILE* comments_input)
 	std::list<std::string> local_to_delete; // opt.to_delete before UTF-8 conversion.
 	bool set_all = false;
 	std::optional<std::string> set_cover;
+	std::optional<std::string> set_vendor;
 	opt = {};
 	if (argc == 1)
 		throw status {st::bad_arguments, "No arguments specified. Use -h for help."};
@@ -128,6 +131,11 @@ ot::options ot::parse_options(int argc, char** argv, FILE* comments_input)
 		case 'v':
 			opt.print_vendor = true;
 			break;
+		case 'V':
+			if (set_vendor)
+				throw status {st::bad_arguments, "Cannot specify --set-vendor more than once."};
+			set_vendor = optarg;
+			break;
 		case 'r':
 			opt.raw = true;
 			break;
@@ -166,12 +174,16 @@ ot::options ot::parse_options(int argc, char** argv, FILE* comments_input)
 			       std::back_inserter(opt.to_add), cast_to_utf8);
 		std::transform(local_to_delete.begin(), local_to_delete.end(),
 			       std::back_inserter(opt.to_delete), cast_to_utf8);
+		if (set_vendor)
+			opt.set_vendor = cast_to_utf8(*set_vendor);
 	} else {
 		try {
 			std::transform(local_to_add.begin(), local_to_add.end(),
 			               std::back_inserter(opt.to_add), encode_utf8);
 			std::transform(local_to_delete.begin(), local_to_delete.end(),
 			               std::back_inserter(opt.to_delete), encode_utf8);
+			if (set_vendor)
+				opt.set_vendor = encode_utf8(*set_vendor);
 		} catch (const ot::status& rc) {
 			throw status {st::bad_arguments, "Could not encode argument into UTF-8: " + rc.message};
 		}
@@ -365,6 +377,9 @@ void ot::delete_comments(std::list<std::u8string>& comments, const std::u8string
 /** Apply the modifications requested by the user to the opustags packet. */
 static void edit_tags(ot::opus_tags& tags, const ot::options& opt)
 {
+	if (opt.set_vendor)
+		tags.vendor = *opt.set_vendor;
+
 	if (opt.delete_all) {
 		tags.comments.clear();
 	} else for (const std::u8string& name : opt.to_delete) {

src/opustags.h

@@ -522,6 +522,12 @@ struct options {
 	 * Option: --vendor
 	 */
 	bool print_vendor = false;
+	/**
+	 * Replace the vendor string by the one specified by the user.
+	 *
+	 * Option: --set-vendor
+	 */
+	std::optional<std::u8string> set_vendor;
 	/**
 	 * Disable encoding conversions. OpusTags are specified to always be encoded as UTF-8, but
 	 * if for some reason a specific file contains binary tags that someone would like to

t/opustags.t

@@ -4,7 +4,7 @@ use strict;
 use warnings;
 use utf8;
 
-use Test::More tests => 60;
+use Test::More tests => 62;
 use Test::Deep qw(cmp_deeply re);
 
 use Digest::MD5;
@@ -323,3 +323,7 @@ END_OUT
 # Vendor string
 
 is_deeply(opustags(qw(--vendor gobble.opus)), ["Lavf58.12.100\n", '', 0], 'print the vendor string');
+
+is_deeply(opustags(qw(--set-vendor opustags gobble.opus -o out.opus)), ['', '', 0], 'set the vendor string');
+is_deeply(opustags(qw(--vendor out.opus)), ["opustags\n", '', 0], 'the vendor string was updated');
+unlink('out.opus');