[FFmpeg-devel] [PATCH] avformat/aviobuf: realloc memory in ffio_ensure_seekback()

[Marton Balint]

On Tue, 15 Sep 2020, Andreas Rheinhardt wrote:

> Marton Balint:
>> 
>> 
>> On Tue, 15 Sep 2020, Paul B Mahol wrote:
>> 
>>> This removes big CPU overhead for demuxing chained ogg streams.
>>>
>>> Signed-off-by: Paul B Mahol <onemda at gmail.com>
>>> ---
>>> libavformat/aviobuf.c | 5 ++---
>>> 1 file changed, 2 insertions(+), 3 deletions(-)
>>>
>>> diff --git a/libavformat/aviobuf.c b/libavformat/aviobuf.c
>>> index a77517d712..6d01150f66 100644
>>> --- a/libavformat/aviobuf.c
>>> +++ b/libavformat/aviobuf.c
>>> @@ -1005,12 +1005,11 @@ int ffio_ensure_seekback(AVIOContext *s,
>>> int64_t buf_size)
>>>         return 0;
>>>     av_assert0(!s->write_flag);
>>>
>>> -    buffer = av_malloc(buf_size);
>>> +    buffer = s->buffer;
>>> +    buffer = av_realloc(buffer, buf_size);
>> 
>> It is not guaranteed that buffer is allocated with av_realloc, so you
>> cannot realloc it.
>> 
>
> This isn't true since 21f70940ae106bfffa07e73057cdb4b5e81a767a any more.

Then av_realloc() docs need updating as well.

Regards,
Marton