[FFmpeg-devel] [PATCH] fftools/ffmpeg: Take type limitations of AVFifo API into account

[Andreas Rheinhardt]

Andreas Rheinhardt:
> The types used by the AVFifo API are inconsistent:
> av_fifo_(space|size)() returns an int; av_fifo_alloc() takes an
> unsigned, other parts use size_t. This commit therefore ensures
> that the size of the muxing_queue FIFO never exceeds INT_MAX.
> 
> While just at it, also make sure not to call av_fifo_size()
> unnecessarily often.
> 
> Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>
> ---
>  fftools/ffmpeg.c     | 9 ++++-----
>  fftools/ffmpeg_opt.c | 1 +
>  2 files changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/fftools/ffmpeg.c b/fftools/ffmpeg.c
> index c9a9cdfcd6..662cd7fda3 100644
> --- a/fftools/ffmpeg.c
> +++ b/fftools/ffmpeg.c
> @@ -753,14 +753,13 @@ static void write_packet(OutputFile *of, AVPacket *pkt, OutputStream *ost, int u
>          AVPacket *tmp_pkt;
>          /* the muxer is not initialized yet, buffer the packet */
>          if (!av_fifo_space(ost->muxing_queue)) {
> +            size_t cur_size = av_fifo_size(ost->muxing_queue);
>              unsigned int are_we_over_size =
>                  (ost->muxing_queue_data_size + pkt->size) > ost->muxing_queue_data_threshold;
> -            int new_size = are_we_over_size ?
> -                           FFMIN(2 * av_fifo_size(ost->muxing_queue),
> -                                 ost->max_muxing_queue_size) :
> -                           2 * av_fifo_size(ost->muxing_queue);
> +            size_t limit    = are_we_over_size ? ost->max_muxing_queue_size : INT_MAX;
> +            size_t new_size = FFMIN(2 * cur_size, limit);
>  
> -            if (new_size <= av_fifo_size(ost->muxing_queue)) {
> +            if (new_size <= cur_size) {
>                  av_log(NULL, AV_LOG_ERROR,
>                         "Too many packets buffered for output stream %d:%d.\n",
>                         ost->file_index, ost->st->index);
> diff --git a/fftools/ffmpeg_opt.c b/fftools/ffmpeg_opt.c
> index 6732a29625..de6af0aea9 100644
> --- a/fftools/ffmpeg_opt.c
> +++ b/fftools/ffmpeg_opt.c
> @@ -1637,6 +1637,7 @@ static OutputStream *new_output_stream(OptionsContext *o, AVFormatContext *oc, e
>  
>      ost->max_muxing_queue_size = 128;
>      MATCH_PER_STREAM_OPT(max_muxing_queue_size, i, ost->max_muxing_queue_size, oc, st);
> +    ost->max_muxing_queue_size = FFMIN(ost->max_muxing_queue_size, INT_MAX / sizeof(ost->pkt));
>      ost->max_muxing_queue_size *= sizeof(ost->pkt);
>  
>      ost->muxing_queue_data_size = 0;
> 

Will apply tonight unless there are objections.

- Andreas