[FFmpeg-devel] [PATCH 1/1] avformat/tcp: support timeout for getaddrinfo For fixing stucking when resolving addrinfo

[XinZheng Zhang]

On Wed, Jun 1, 2016 at 12:03 PM, XinZheng Zhang <zhangxzheng at gmail.com> wrote:
> On Tue, May 31, 2016 at 9:33 PM, Hendrik Leppkes <h.leppkes at gmail.com> wrote:
>>
>> On Tue, May 31, 2016 at 2:58 PM, Xinzheng Zhang <zhangxzheng at gmail.com> wrote:
>> > ---
>> >  libavformat/tcp.c | 215 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
>> >  1 file changed, 215 insertions(+)
>> >
>>
>> This whole patch looks extremely complicated and long for something
>> hidden behind a tiny option not saying much.
>> Maybe you should start by elaborating in detail what you are trying to
>> fix, how you are fixing it, and why you choose this approach and not
>> any others that may appear simpler.
>>
>
> For some ugly network conditions(Eg.Mobile device in a WiFi network,
> but offline from internet), getaddrinfo() could block tcp_open() for a
> long time,
> neither timeout nor interrupt callback can save us.
>
> There are serveral way to fix this issue
> AFAIK. We can use `getaddrinfo_a` on some linux platform
> http://man7.org/linux/man-pages/man3/getaddrinfo_a.3.html
> But, it doesn't work on other platforms.
>
> Besides, we can put this task into a background thread,
> and detach from it when we want to cancel the task,
> or it is timed out. But unfortunately,
> there are no global thread pool or other background facility
> to host such detached tasks in ffmpeg


Ping.