[FFmpeg-devel] [PATCH 4/4] avformat/udp: do not use thread cancellation when receiving data

[Marton Balint]

On Fri, 17 Jan 2020, Michael Niedermayer wrote:

> On Thu, Jan 16, 2020 at 01:20:16AM +0100, Marton Balint wrote:
>> It is not supported by every threading implementation, and the only thing we
>> gain with it is an immediate shutdown of receiving packets on close and
>> avoiding the poll call before reading the data.
>>
>> I don't think it is a big issue if it takes 0.1 sec of delay to close an udp
>> stream. Back when this was introduced the delay was 1 sec, which was indeed
>> noticable.
>>
>> And anybody who needs performance sensitive UDP should not use the fifo buffer
>> in the first place, because the kernel can buffer the data much more
>> effectively.

This patch also fixes ticket #5717 by the way.

>>
>> Signed-off-by: Marton Balint <cus at passwd.hu>
>> ---
>>  libavformat/udp.c | 57 +++++++++++++++++++++++++------------------------------
>>  1 file changed, 26 insertions(+), 31 deletions(-)
>
> this breaks build on mingw64
>
> src/libavformat/udp.c: In function ‘udp_read’:
> src/libavformat/udp.c:980:17: error: implicit declaration of function ‘pthread_cond_timedwait’ [-Werror=implicit-function-declaration]
>                 int err = pthread_cond_timedwait(&s->cond, &s->mutex, &tv);
>                 ^
> cc1: some warnings being treated as errors
> make: *** [libavformat/udp.o] Error 1
> make: *** Waiting for unfinished jobs....

With the pthread_cond_timedwait compat patch applied, this should no 
longer be an issue.

Regards,
Marton