[FFmpeg-devel] [PATCH v2 1/7] avformat/matroskadec: support parsing more than one BlockMore element

[Andreas Rheinhardt]

James Almer:
> Signed-off-by: James Almer <jamrial at gmail.com>
> ---
> No changes since v1.
> 
>  libavformat/matroskadec.c | 60 ++++++++++++++++++++++++++-------------
>  1 file changed, 40 insertions(+), 20 deletions(-)
> 
> diff --git a/libavformat/matroskadec.c b/libavformat/matroskadec.c
> index 3a888e3ada..60f9a78fe8 100644
> --- a/libavformat/matroskadec.c
> +++ b/libavformat/matroskadec.c
> @@ -349,13 +349,17 @@ typedef struct MatroskaLevel {
>      uint64_t length;
>  } MatroskaLevel;
>  
> +typedef struct MatroskaBlockMore {
> +    uint64_t additional_id;
> +    EbmlBin  additional;
> +} MatroskaBlockMore;
> +
>  typedef struct MatroskaBlock {
>      uint64_t duration;
>      CountedElement reference;
>      uint64_t non_simple;
>      EbmlBin  bin;
> -    uint64_t additional_id;
> -    EbmlBin  additional;
> +    EbmlList blockmore;
>      int64_t  discard_padding;
>  } MatroskaBlock;
>  
> @@ -759,13 +763,13 @@ static EbmlSyntax matroska_segments[] = {
>  };
>  
>  static EbmlSyntax matroska_blockmore[] = {
> -    { MATROSKA_ID_BLOCKADDID,      EBML_UINT, 0, 0, offsetof(MatroskaBlock,additional_id), { .u = 1 } },
> -    { MATROSKA_ID_BLOCKADDITIONAL, EBML_BIN,  0, 0, offsetof(MatroskaBlock,additional) },
> +    { MATROSKA_ID_BLOCKADDID,      EBML_UINT, 0, 0, offsetof(MatroskaBlockMore,additional_id), { .u = 1 } },
> +    { MATROSKA_ID_BLOCKADDITIONAL, EBML_BIN,  0, 0, offsetof(MatroskaBlockMore,additional) },
>      CHILD_OF(matroska_blockadditions)
>  };
>  
>  static EbmlSyntax matroska_blockadditions[] = {
> -    { MATROSKA_ID_BLOCKMORE, EBML_NEST, 0, 0, 0, {.n = matroska_blockmore} },
> +    { MATROSKA_ID_BLOCKMORE, EBML_NEST, 0, sizeof(MatroskaBlockMore), offsetof(MatroskaBlock, blockmore), { .n = matroska_blockmore } },
>      CHILD_OF(matroska_blockgroup)
>  };
>  
> @@ -3610,12 +3614,28 @@ static int matroska_parse_webvtt(MatroskaDemuxContext *matroska,
>      return 0;
>  }
>  
> +static int matroska_parse_block_additional(MatroskaDemuxContext *matroska,
> +                                           AVPacket *pkt,
> +                                           const uint8_t *data, int size, uint64_t id)
> +{
> +    uint8_t *side_data = av_packet_new_side_data(pkt,
> +                                                 AV_PKT_DATA_MATROSKA_BLOCKADDITIONAL,
> +                                                 size + 8);

size + (size_t)8

> +    if (!side_data)
> +        return AVERROR(ENOMEM);
> +
> +    AV_WB64(side_data, id);
> +    memcpy(side_data + 8, data, size);
> +
> +    return 0;
> +}
> +
>  static int matroska_parse_frame(MatroskaDemuxContext *matroska,
>                                  MatroskaTrack *track, AVStream *st,
>                                  AVBufferRef *buf, uint8_t *data, int pkt_size,
>                                  uint64_t timecode, uint64_t lace_duration,
>                                  int64_t pos, int is_keyframe,
> -                                uint8_t *additional, uint64_t additional_id, int additional_size,
> +                                MatroskaBlockMore *blockmore, int nb_blockmore,
>                                  int64_t discard_padding)
>  {
>      uint8_t *pkt_data = data;
> @@ -3647,7 +3667,7 @@ static int matroska_parse_frame(MatroskaDemuxContext *matroska,
>          buf = NULL;
>      }
>  
> -    if (!pkt_size && !additional_size)
> +    if (!pkt_size && !nb_blockmore)
>          goto no_output;
>  
>      if (!buf)
> @@ -3666,16 +3686,18 @@ static int matroska_parse_frame(MatroskaDemuxContext *matroska,
>      pkt->flags        = is_keyframe;
>      pkt->stream_index = st->index;
>  
> -    if (additional_size > 0) {
> -        uint8_t *side_data = av_packet_new_side_data(pkt,
> -                                                     AV_PKT_DATA_MATROSKA_BLOCKADDITIONAL,
> -                                                     additional_size + 8);
> -        if (!side_data) {
> +    for (int i = 0; i < nb_blockmore; i++) {
> +        MatroskaBlockMore *more = &blockmore[i];
> +
> +        if (!more->additional.size)
> +            continue;
> +
> +        res = matroska_parse_block_additional(matroska, pkt, more->additional.data,
> +                                              more->additional.size, more->additional_id);
> +        if (res < 0) {
>              av_packet_unref(pkt);
>              return AVERROR(ENOMEM);

return res;

>          }
> -        AV_WB64(side_data, additional_id);
> -        memcpy(side_data + 8, additional, additional_size);
>      }
>  
>      if (discard_padding) {
> @@ -3721,7 +3743,7 @@ fail:
>  static int matroska_parse_block(MatroskaDemuxContext *matroska, AVBufferRef *buf, uint8_t *data,
>                                  int size, int64_t pos, uint64_t cluster_time,
>                                  uint64_t block_duration, int is_keyframe,
> -                                uint8_t *additional, uint64_t additional_id, int additional_size,
> +                                MatroskaBlockMore *blockmore, int nb_blockmore,
>                                  int64_t cluster_pos, int64_t discard_padding)
>  {
>      uint64_t timecode = AV_NOPTS_VALUE;
> @@ -3856,7 +3878,7 @@ static int matroska_parse_block(MatroskaDemuxContext *matroska, AVBufferRef *buf
>              res = matroska_parse_frame(matroska, track, st, buf, out_data,
>                                         out_size, timecode, lace_duration,
>                                         pos, !n ? is_keyframe : 0,
> -                                       additional, additional_id, additional_size,
> +                                       blockmore, nb_blockmore,
>                                         discard_padding);
>              if (res)
>                  return res;
> @@ -3897,14 +3919,12 @@ static int matroska_parse_cluster(MatroskaDemuxContext *matroska)
>  
>          if (res >= 0 && block->bin.size > 0) {
>              int is_keyframe = block->non_simple ? block->reference.count == 0 : -1;
> -            uint8_t* additional = block->additional.size > 0 ?
> -                                    block->additional.data : NULL;
>  
>              res = matroska_parse_block(matroska, block->bin.buf, block->bin.data,
>                                         block->bin.size, block->bin.pos,
>                                         cluster->timecode, block->duration,
> -                                       is_keyframe, additional, block->additional_id,
> -                                       block->additional.size, cluster->pos,
> +                                       is_keyframe, block->blockmore.elem,
> +                                       block->blockmore.nb_elem, cluster->pos,
>                                         block->discard_padding);
>          }
>