[FFmpeg-devel] [PATCH 1/1] libavformat/rtsp.c: Reply to GET_PARAMETER requests

[Martin Storsjö]

On Fri, 25 Jun 2021, Hayden Myers wrote:

> Some encoders send GET_PARAMETER requests as a keep-alive mechanism.
> If the client doesn't reply with an OK message, the encoder will close
> the session.  This was encountered with the impath i5110 encoder, when
> the RTSP Keep-Alive checkbox is enabled under streaming settings.
> Alternatively one may set the X-No-Keepalive: 1 header, but this is more
> of a workaround.  It's better practice to respond to an encoder's
> keep-alive request, than disable the mechanism which may be manufacturer
> specific.
>
> Signed-off-by: Hayden Myers <hmyers at skylinenet.net>
> ---
>  libavformat/rtsp.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/libavformat/rtsp.c b/libavformat/rtsp.c
> index 9f509a229f..dc660368f0 100644
> --- a/libavformat/rtsp.c
> +++ b/libavformat/rtsp.c
> @@ -1259,7 +1259,9 @@ start:
>          char base64buf[AV_BASE64_SIZE(sizeof(buf))];
>          const char* ptr = buf;
>
> -        if (!strcmp(reply->reason, "OPTIONS")) {
> +        if (!strcmp(reply->reason, "OPTIONS") ||
> +            !strcmp(reply->reason, "GET_PARAMETER")) {
> +
>              snprintf(buf, sizeof(buf), "RTSP/1.0 200 OK\r\n");
>              if (reply->seq)
>                  av_strlcatf(buf, sizeof(buf), "CSeq: %d\r\n", reply->seq);
> --

LGTM, this sounds and seems reasonable to me (although untested in 
practice).

// Martin