[FFmpeg-devel] [PATCH 1/2] avformat/oggdec: Factor buffer reallocation out

[Lynne]

May 1, 2020, 14:16 by michael at niedermayer.cc:

> Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
> ---
>  libavformat/oggdec.c | 25 +++++++++++++++++--------
>  1 file changed, 17 insertions(+), 8 deletions(-)
>
> diff --git a/libavformat/oggdec.c b/libavformat/oggdec.c
> index c591bafddd..a9034ea61c 100644
> --- a/libavformat/oggdec.c
> +++ b/libavformat/oggdec.c
> @@ -297,6 +297,20 @@ static int data_packets_seen(const struct ogg *ogg)
>  return 0;
>  }
>  
> +static int buf_realloc(struct ogg_stream *os, int size)
> +{
> +    /* Even if invalid guarantee there's enough memory to read the page */
> +    if (os->bufsize - os->bufpos < size) {
> +        uint8_t *nb = av_realloc(os->buf, 2*os->bufsize + AV_INPUT_BUFFER_PADDING_SIZE);
> +        if (!nb)
> +            return AVERROR(ENOMEM);
> +        os->buf = nb;
> +        os->bufsize *= 2;
> +    }
>

Looking at the code, this is just av_fast_realloc.
You could change it to that, or you could just allocate MAX_PAGE_SIZE at the start and never reallocate. Its only 65k.
Up to you, feel free to commit whatever you choose.