[FFmpeg-devel] [PATCH V2 1/2] lavf/libsrt: add linger parameter to libsrt

[mypopy at gmail.com]

On Mon, Dec 2, 2019 at 12:57 PM Andriy Gelman <andriy.gelman at gmail.com>
wrote:
>
> On Sun, 01. Dec 21:31, Jun Zhao wrote:
> > From: Jun Zhao <barryjzhao at tencent.com>
> >
> > add linger parameter to libsrt, it's setting he number of seconds
> > that the socket waits for unsent data when closing.
>
> minor spelling
>
Will fix
> >
> > Signed-off-by: Jun Zhao <barryjzhao at tencent.com>
> > ---
> >  doc/protocols.texi   |    4 ++++
> >  libavformat/libsrt.c |   13 +++++++++++++
> >  2 files changed, 17 insertions(+), 0 deletions(-)
> >
> > diff --git a/doc/protocols.texi b/doc/protocols.texi
> > index 0e18a49..f34f246 100644
> > --- a/doc/protocols.texi
> > +++ b/doc/protocols.texi
> > @@ -1426,6 +1426,10 @@ the overhead transmission (retransmitted and
control packets).
> >  file: Set options as for non-live transmission. See @option{messageapi}
> >  for further explanations
> >
>
> > + at item linger=@var{seconds}
> > +The number of seconds that the socket waits for unsent data when
closing.
> > +Default is -1.
>
> I'd add infinite in brackets.
Can't get your point, more details?
>
> > +
> >  @end table
> >
> >  For more information see: @url{https://github.com/Haivision/srt}.
> > diff --git a/libavformat/libsrt.c b/libavformat/libsrt.c
> > index 1c34ec5..0a748a1 100644
> > --- a/libavformat/libsrt.c
> > +++ b/libavformat/libsrt.c
> > @@ -84,6 +84,7 @@ typedef struct SRTContext {
> >      char *smoother;
> >      int messageapi;
> >      SRT_TRANSTYPE transtype;
> > +    int linger;
> >  } SRTContext;
> >
> >  #define D AV_OPT_FLAG_DECODING_PARAM
> > @@ -128,6 +129,7 @@ static const AVOption libsrt_options[] = {
> >      { "transtype",      "The transmission type for the socket",
                          OFFSET(transtype),        AV_OPT_TYPE_INT,      {
.i64 = SRTT_INVALID }, SRTT_LIVE, SRTT_INVALID, .flags = D|E, "transtype" },
> >      { "live",           NULL, 0, AV_OPT_TYPE_CONST,  { .i64 =
SRTT_LIVE }, INT_MIN, INT_MAX, .flags = D|E, "transtype" },
> >      { "file",           NULL, 0, AV_OPT_TYPE_CONST,  { .i64 =
SRTT_FILE }, INT_MIN, INT_MAX, .flags = D|E, "transtype" },
> > +    { "linger",         "Number of seconds that the socket waits for
unsent data when closing", OFFSET(linger),           AV_OPT_TYPE_INT,
 { .i64 = -1 }, -1, INT_MAX,   .flags = D|E },
> >      { NULL }
> >  };
> >
>
> Are some other parameters (latency, rcvlatency, connect_timeout) in
milliseconds? (It's not that clear from the docs).
> If yes, it may be good to set linger to milliseconds as well.
>
The SRT docs (https://github.com/Haivision/srt/blob/master/docs/API.md)
used the seconds,  and I think SRT borrow the option from socket SO_LINGER
(http://man7.org/linux/man-pages/man7/socket.7.html), we can keep the
similar semantics with seconds.
> --
> Andriy