After this change we always parse the full specifier even if we know the result in the middle of the parsing. Sligtly slower, but this is needed to consistently reject incorrect specifiers in both matching and non-matching cases.
Signed-off-by: Marton Balint <c...@passwd.hu> --- libavformat/utils.c | 26 +++++++++++++++----------- 1 file changed, 15 insertions(+), 11 deletions(-) diff --git a/libavformat/utils.c b/libavformat/utils.c index 39290a647d..81f72bbf83 100644 --- a/libavformat/utils.c +++ b/libavformat/utils.c @@ -5109,11 +5109,12 @@ AVRational av_guess_frame_rate(AVFormatContext *format, AVStream *st, AVFrame *f static int match_stream_specifier(AVFormatContext *s, AVStream *st, const char *spec, const char **indexptr) { + int match = 1; /* Stores if the specifier matches so far. */ while (*spec) { if (*spec <= '9' && *spec >= '0') { /* opt:index */ if (indexptr) *indexptr = spec; - return 1; + return match; } else if (*spec == 'v' || *spec == 'a' || *spec == 's' || *spec == 'd' || *spec == 't' || *spec == 'V') { /* opt:[vasdtV] */ enum AVMediaType type; @@ -5135,14 +5136,14 @@ static int match_stream_specifier(AVFormatContext *s, AVStream *st, FF_DISABLE_DEPRECATION_WARNINGS if (type != st->codecpar->codec_type && (st->codecpar->codec_type != AVMEDIA_TYPE_UNKNOWN || st->codec->codec_type != type)) - return 0; + match = 0; FF_ENABLE_DEPRECATION_WARNINGS #else if (type != st->codecpar->codec_type) - return 0; + match = 0; #endif if (nopic && (st->disposition & AV_DISPOSITION_ATTACHED_PIC)) - return 0; + match = 0; } else if (*spec == 'p' && *(spec + 1) == ':') { int prog_id, i, j; int found = 0; @@ -5153,6 +5154,7 @@ FF_ENABLE_DEPRECATION_WARNINGS if (spec == endptr || (*endptr && *endptr++ != ':')) return AVERROR(EINVAL); spec = endptr; + if (match) { for (i = 0; i < s->nb_programs; i++) { if (s->programs[i]->id != prog_id) continue; @@ -5165,8 +5167,9 @@ FF_ENABLE_DEPRECATION_WARNINGS } } } + } if (!found) - return 0; + match = 0; } else if (*spec == '#' || (*spec == 'i' && *(spec + 1) == ':')) { int stream_id; @@ -5175,12 +5178,13 @@ FF_ENABLE_DEPRECATION_WARNINGS stream_id = strtol(spec, &endptr, 0); if (spec == endptr || *endptr) /* Disallow empty id and make sure we are at the end. */ return AVERROR(EINVAL); - return stream_id == st->id; + return match && (stream_id == st->id); } else if (*spec == 'm' && *(spec + 1) == ':') { AVDictionaryEntry *tag; char *key, *val; int ret; + if (match) { spec += 2; val = strchr(spec, ':'); @@ -5198,7 +5202,8 @@ FF_ENABLE_DEPRECATION_WARNINGS ret = 0; av_freep(&key); - return ret; + } + return match && ret; } else if (*spec == 'u' && *(spec + 1) == '\0') { AVCodecParameters *par = st->codecpar; #if FF_API_LAVF_AVCTX @@ -5240,17 +5245,16 @@ FF_ENABLE_DEPRECATION_WARNINGS break; } #if FF_API_LAVF_AVCTX - return (par->codec_id != AV_CODEC_ID_NONE || codec->codec_id != AV_CODEC_ID_NONE) && val != 0; + return match && ((par->codec_id != AV_CODEC_ID_NONE || codec->codec_id != AV_CODEC_ID_NONE) && val != 0); #else - return par->codec_id != AV_CODEC_ID_NONE && val != 0; + return match && (par->codec_id != AV_CODEC_ID_NONE && val != 0); #endif } else { return AVERROR(EINVAL); } } - /* empty specifier, matches everything */ - return 1; + return match; } -- 2.16.4 _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel