[FFmpeg-devel] [PATCH] rtp: Fix play multiple multicast streams with the same port

[Zhao Zhili]

I made a mistake that rtp and rtcp cannot be the same port. A new patch is
appended.

From: Zhao Zhili <wantlamy at gmail.com>
Date: Thu, 7 Jan 2016 18:55:50 +0800
Subject: [PATCH] rtp: Fix play multiple multicast streams with the same port

We cannot play multiple multicast streams with the same port at the
same time. This is because both rtp and rtcp port are opened in
read-write mode, so they will not bind to the multicast address. Try
to make rtp port as read-only by default to solve this bug.

Signed-off-by: Zhao Zhili <wantlamy at gmail.com>
---
 libavformat/rtpproto.c | 6 ++++--
 libavformat/rtsp.c     | 2 +-
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/libavformat/rtpproto.c b/libavformat/rtpproto.c
index e0aa23e..04a40ea 100644
--- a/libavformat/rtpproto.c
+++ b/libavformat/rtpproto.c
@@ -323,6 +323,7 @@ static int rtp_open(URLContext *h, const char *uri, int
flags)
     char path[1024];
     const char *p;
     int i, max_retry_count = 3;
+    int rtcpflags;

     av_url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &rtp_port,
                  path, sizeof(path), uri);
@@ -387,12 +388,13 @@ static int rtp_open(URLContext *h, const char *uri,
int flags)
             s->local_rtpport = -1;
             continue;
         }
+        rtcpflags = flags | AVIO_FLAG_WRITE;
         if (s->local_rtcpport < 0) {
             s->local_rtcpport = s->local_rtpport + 1;
             build_udp_url(s, buf, sizeof(buf),
                           hostname, s->rtcp_port, s->local_rtcpport,
                           sources, block);
-            if (ffurl_open(&s->rtcp_hd, buf, flags,
&h->interrupt_callback, NULL) < 0) {
+            if (ffurl_open(&s->rtcp_hd, buf, rtcpflags,
&h->interrupt_callback, NULL) < 0) {
                 s->local_rtpport = s->local_rtcpport = -1;
                 continue;
             }
@@ -401,7 +403,7 @@ static int rtp_open(URLContext *h, const char *uri, int
flags)
         build_udp_url(s, buf, sizeof(buf),
                       hostname, s->rtcp_port, s->local_rtcpport,
                       sources, block);
-        if (ffurl_open(&s->rtcp_hd, buf, flags, &h->interrupt_callback,
NULL) < 0)
+        if (ffurl_open(&s->rtcp_hd, buf, rtcpflags,
&h->interrupt_callback, NULL) < 0)
             goto fail;
         break;
     }
diff --git a/libavformat/rtsp.c b/libavformat/rtsp.c
index 39539e9..8cae376 100644
--- a/libavformat/rtsp.c
+++ b/libavformat/rtsp.c
@@ -2316,7 +2316,7 @@ static int sdp_read_header(AVFormatContext *s)
             append_source_addrs(url, sizeof(url), "block",
                                 rtsp_st->nb_exclude_source_addrs,
                                 rtsp_st->exclude_source_addrs);
-            err = ffurl_open(&rtsp_st->rtp_handle, url,
AVIO_FLAG_READ_WRITE,
+            err = ffurl_open(&rtsp_st->rtp_handle, url, AVIO_FLAG_READ,
                            &s->interrupt_callback, &opts);

             av_dict_free(&opts);
-- 
1.9.1