[FFmpeg-devel] [PATCH 10/16] vmdaudio: simplify buffer pointer and header size handling.

[Kostya]

On Wed, Feb 23, 2011 at 01:11:07PM -0500, Justin Ruggles wrote:
> ---
>  libavcodec/vmdav.c |   19 ++++++++++---------
>  1 files changed, 10 insertions(+), 9 deletions(-)
> 

> diff --git a/libavcodec/vmdav.c b/libavcodec/vmdav.c
> index 0cef203..48739a7 100644
> --- a/libavcodec/vmdav.c
> +++ b/libavcodec/vmdav.c
> @@ -508,9 +508,6 @@ static int vmdaudio_decode_frame(AVCodecContext *avctx,
>      int block_type;
>      unsigned char *output_samples = (unsigned char *)data;
>  
> -    /* point to the start of the encoded data */
> -    const unsigned char *p = buf + 16;
> -
>      if (buf_size < 16) {
>          av_log(avctx, AV_LOG_WARNING, "skipping small junk packet\n");
>          *data_size = 0;
> @@ -522,29 +519,33 @@ static int vmdaudio_decode_frame(AVCodecContext *avctx,
>          av_log(avctx, AV_LOG_ERROR, "unknown block type: %d\n", block_type);
>          return AVERROR(EINVAL);
>      }
> +    buf      += 16;
> +    buf_size -= 16;
>  
>      if (block_type == BLOCK_TYPE_AUDIO) {
>          /* the chunk contains audio */
> -        *data_size = vmdaudio_loadsound(s, output_samples, p, 0, buf_size - 16);
> +        *data_size = vmdaudio_loadsound(s, output_samples, buf, 0, buf_size);
>      } else if (block_type == BLOCK_TYPE_INITIAL) {
>          /* initial chunk, may contain audio and silence */
> -        uint32_t flags = AV_RB32(p);
> +        uint32_t flags = AV_RB32(buf);
>          int raw_block_size = s->block_align *
>                               (av_get_bits_per_sample_fmt(avctx->sample_fmt) / 8);
>          int silent_chunks = av_popcount(flags);
> -        if(*data_size < (s->block_align*silent_chunks + buf_size - 20) * 2)
> +        buf      += 4;
> +        buf_size -= 4;
> +        if(*data_size < (s->block_align*silent_chunks + buf_size) * 2)
>              return -1;
>          *data_size = 0;
>          memset(output_samples, 0, raw_block_size * silent_chunks);
>          output_samples += raw_block_size * silent_chunks;
>          *data_size = raw_block_size * silent_chunks;
> -        *data_size += vmdaudio_loadsound(s, output_samples, p + 4, 0, buf_size - 20);
> +        *data_size += vmdaudio_loadsound(s, output_samples, buf, 0, buf_size);
>      } else if (block_type == BLOCK_TYPE_SILENCE) {
>          /* silent chunk */
> -        *data_size = vmdaudio_loadsound(s, output_samples, p, 1, s->block_align);
> +        *data_size = vmdaudio_loadsound(s, output_samples, buf, 1, s->block_align);
>      }
>  
> -    return buf_size;
> +    return avpkt->size;
>  }
>  
>  

looks ok