avformat/matroskaenc: write a CRC32 element on Tracks

Implements part of ticket #4347

Tested-by: Dave Rice <dave@dericed.com>
Tested-by: Jerome Martinez <jerome@mediaarea.net>
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: James Almer <jamrial@gmail.com>

1 files changed, 7 insertions, 4 deletions

diff --git a/libavformat/matroskaenc.c b/libavformat/matroskaenc.c
index 5009ebc6fc..b3a3b941b1 100644
--- a/libavformat/matroskaenc.c
+++ b/libavformat/matroskaenc.c
@@ -1242,7 +1242,7 @@ static int mkv_write_track(AVFormatContext *s, MatroskaMuxContext *mkv,
 static int mkv_write_tracks(AVFormatContext *s)
 {
     MatroskaMuxContext *mkv = s->priv_data;
-    AVIOContext *pb = s->pb;
+    AVIOContext *dyn_cp, *pb = s->pb;
     ebml_master tracks;
     int i, ret, default_stream_exists = 0;
 
@@ -1250,17 +1250,20 @@ static int mkv_write_tracks(AVFormatContext *s)
     if (ret < 0)
         return ret;
 
-    tracks = start_ebml_master(pb, MATROSKA_ID_TRACKS, 0);
+    ret = start_ebml_master_crc32(pb, &dyn_cp, &tracks, MATROSKA_ID_TRACKS, 0);
+    if (ret < 0)
+        return ret;
+
     for (i = 0; i < s->nb_streams; i++) {
         AVStream *st = s->streams[i];
         default_stream_exists |= st->disposition & AV_DISPOSITION_DEFAULT;
     }
     for (i = 0; i < s->nb_streams; i++) {
-        ret = mkv_write_track(s, mkv, i, pb, default_stream_exists);
+        ret = mkv_write_track(s, mkv, i, dyn_cp, default_stream_exists);
         if (ret < 0)
             return ret;
     }
-    end_ebml_master(pb, tracks);
+    end_ebml_master_crc32(pb, &dyn_cp, mkv, tracks);
     return 0;
 }