[FFmpeg-devel] [PATCH 1/2] mpegts: add all stream languages into metadata

[Ronald S. Bultje]

Hi,

On Thu, Feb 17, 2011 at 10:26 AM, Anssi Hannula <anssi.hannula at iki.fi> wrote:
> This is used at least on some older DVB broadcasts for dual-mono audio
> tracks.
> ---
>
> Here goes the patchset without the channelX/language stuff.
> I also changed the language separator from '+' from ',', but I'm open
> to bikeshedding.
>
> ?libavformat/mpegts.c | ? 18 ++++++++++++------
> ?1 files changed, 12 insertions(+), 6 deletions(-)
>
> diff --git a/libavformat/mpegts.c b/libavformat/mpegts.c
> index abb6f08..c7e4fe3 100644
> --- a/libavformat/mpegts.c
> +++ b/libavformat/mpegts.c
> @@ -890,7 +890,8 @@ int ff_parse_mpeg2_descriptor(AVFormatContext *fc, AVStream *st, int stream_type
> ?{
> ? ? const uint8_t *desc_end;
> ? ? int desc_len, desc_tag;
> - ? ?char language[4];
> + ? ?char language[252];
> + ? ?int i;
>
> ? ? desc_tag = get8(pp, desc_list_end);
> ? ? if (desc_tag < 0)
> @@ -949,16 +950,21 @@ int ff_parse_mpeg2_descriptor(AVFormatContext *fc, AVStream *st, int stream_type
> ? ? ? ? av_metadata_set2(&st->metadata, "language", language, 0);
> ? ? ? ? break;
> ? ? case 0x0a: /* ISO 639 language descriptor */
> - ? ? ? ?language[0] = get8(pp, desc_end);
> - ? ? ? ?language[1] = get8(pp, desc_end);
> - ? ? ? ?language[2] = get8(pp, desc_end);
> - ? ? ? ?language[3] = 0;
> - ? ? ? ?av_metadata_set2(&st->metadata, "language", language, 0);
> + ? ? ? ?for (i = 0; i + 4 <= desc_len; i += 4) {
> + ? ? ? ? ? ?language[i + 0] = get8(pp, desc_end);
> + ? ? ? ? ? ?language[i + 1] = get8(pp, desc_end);
> + ? ? ? ? ? ?language[i + 2] = get8(pp, desc_end);
> + ? ? ? ? ? ?language[i + 3] = ',';
> ? ? ? ? switch (get8(pp, desc_end)) {
> ? ? ? ? ? ? case 0x01: st->disposition |= AV_DISPOSITION_CLEAN_EFFECTS; break;
> ? ? ? ? ? ? case 0x02: st->disposition |= AV_DISPOSITION_HEARING_IMPAIRED; break;
> ? ? ? ? ? ? case 0x03: st->disposition |= AV_DISPOSITION_VISUAL_IMPAIRED; break;
> ? ? ? ? }
> + ? ? ? ?}
> + ? ? ? ?if (i) {
> + ? ? ? ? ? ?language[i - 1] = 0;
> + ? ? ? ? ? ?av_metadata_set2(&st->metadata, "language", language, 0);
> + ? ? ? ?}

if language[] is 252 bytes, can this overflow? There's no checks for i
being under 252.

Ronald