[FFmpeg-devel] [PATCH] libavformat/id3v2: Read full null seperated list for text info frames

[Lode Willems]

All id3v2.4 text information frames are null separated lists:
https://id3.org/id3v2.4.0-frames

This change reads all values into the metadata dictionary without changing the
outputs of ffmpeg or ffprobe

Relevant ticket: https://trac.ffmpeg.org/ticket/6949

Signed-off-by: Lode Willems <me at lodewillems.com>
---
 libavformat/id3v2.c    | 5 ++++-
 libavformat/metadata.c | 2 +-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/libavformat/id3v2.c b/libavformat/id3v2.c
index 863709abbf..9ef56a52c2 100644
--- a/libavformat/id3v2.c
+++ b/libavformat/id3v2.c
@@ -320,7 +320,7 @@ static void read_ttag(AVFormatContext *s, AVIOContext *pb, int taglen,
                       AVDictionary **metadata, const char *key)
 {
     uint8_t *dst;
-    int encoding, dict_flags = AV_DICT_DONT_OVERWRITE | AV_DICT_DONT_STRDUP_VAL;
+    int encoding, dict_flags = AV_DICT_DONT_OVERWRITE | AV_DICT_DONT_STRDUP_VAL | AV_DICT_MULTIKEY;
     unsigned genre;
 
     if (taglen < 1)
@@ -329,6 +329,8 @@ static void read_ttag(AVFormatContext *s, AVIOContext *pb, int taglen,
     encoding = avio_r8(pb);
     taglen--; /* account for encoding type byte */
 
+    /* Read all null-terminated values */
+    while (taglen > 0) {
     if (decode_str(s, pb, encoding, &dst, &taglen) < 0) {
         av_log(s, AV_LOG_ERROR, "Error reading frame %s, skipped\n", key);
         return;
@@ -353,6 +355,7 @@ static void read_ttag(AVFormatContext *s, AVIOContext *pb, int taglen,
 
     if (dst)
         av_dict_set(metadata, key, dst, dict_flags);
+    }
 }
 
 static void read_uslt(AVFormatContext *s, AVIOContext *pb, int taglen,
diff --git a/libavformat/metadata.c b/libavformat/metadata.c
index b9b6de7972..68382e7937 100644
--- a/libavformat/metadata.c
+++ b/libavformat/metadata.c
@@ -50,7 +50,7 @@ void ff_metadata_conv(AVDictionary **pm, const AVMetadataConv *d_conv,
                     key = dc->native;
                     break;
                 }
-        av_dict_set(&dst, key, mtag->value, 0);
+        av_dict_set(&dst, key, mtag->value, AV_DICT_DONT_OVERWRITE);
     }
     av_dict_free(pm);
     *pm = dst;
-- 
2.31.0