demux_lavf: workaround minor ffmpeg memory leak

The sequence of avcodec_alloc_context3() / avcodec_copy_context() /
avcodec_close() / av_free() leaks some memory. So don't copy the context
and use it directly.

Originally avcodec_copy_context() was used to guarantee that libavformat
can't update the fields of the context during demuxing in order to make
things a little more robust, but it's not strictly needed, and
ffmpeg/ffplay don't do this anyway. Still might make the situation worse
should we move demuxing into a separate thread, though.

2 files changed, 1 insertions, 7 deletions

diff --git a/demux/demux.c b/demux/demux.c
index b027f896de..c379ee4736 100644
--- a/demux/demux.c
+++ b/demux/demux.c
@@ -315,10 +315,6 @@ struct sh_stream *new_sh_stream(demuxer_t *demuxer, enum stream_type type)
 
 static void free_sh_stream(struct sh_stream *sh)
 {
-    if (sh->lav_headers) {
-        avcodec_close(sh->lav_headers);
-        av_free(sh->lav_headers);
-    }
 }
 
 sh_sub_t *new_sh_sub_sid(demuxer_t *demuxer, int id, int sid)
diff --git a/demux/demux_lavf.c b/demux/demux_lavf.c
index 279f7f7b33..5eebffc2f9 100644
--- a/demux/demux_lavf.c
+++ b/demux/demux_lavf.c
@@ -423,9 +423,7 @@ static void handle_stream(demuxer_t *demuxer, int i)
 
     if (sh) {
         sh->codec = mp_codec_from_av_codec_id(codec->codec_id);
-        sh->lav_headers = avcodec_alloc_context3(codec->codec);
-        assert(sh->lav_headers);
-        avcodec_copy_context(sh->lav_headers, codec);
+        sh->lav_headers = codec;
 
         if (st->disposition & AV_DISPOSITION_DEFAULT)
             sh->default_track = 1;