From b7dc88fc68759ddd79caf291d75e715930362aac Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20Storsj=C3=B6?= <martin@martin.st>
Date: Mon, 22 Mar 2010 15:07:05 +0000
Subject: [PATCH] Add support for TCP as lower transport in the RTSP muxer

Originally committed as revision 22634 to svn://svn.ffmpeg.org/ffmpeg/trunk
---
 libavformat/rtsp.c    | 22 +++++++++++++++++++---
 libavformat/rtspenc.c | 44 ++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 62 insertions(+), 4 deletions(-)

diff --git a/libavformat/rtsp.c b/libavformat/rtsp.c
index 160495b5f8..7e754336b8 100644
--- a/libavformat/rtsp.c
+++ b/libavformat/rtsp.c
@@ -584,7 +584,13 @@ void ff_rtsp_close_streams(AVFormatContext *s)
                 if (s->oformat) {
                     AVFormatContext *rtpctx = rtsp_st->transport_priv;
                     av_write_trailer(rtpctx);
+                    if (rt->lower_transport == RTSP_LOWER_TRANSPORT_TCP) {
+                        uint8_t *ptr;
+                        url_close_dyn_buf(rtpctx->pb, &ptr);
+                        av_free(ptr);
+                    } else {
                     url_fclose(rtpctx->pb);
+                    }
                     av_metadata_free(&rtpctx->streams[0]->metadata);
                     av_metadata_free(&rtpctx->metadata);
                     av_free(rtpctx->streams[0]);
@@ -644,11 +650,20 @@ static void *rtsp_rtp_mux_open(AVFormatContext *s, AVStream *st,
     av_free(rtpctx->streams[0]->codec);
     rtpctx->streams[0]->codec = st->codec;
 
+    if (handle) {
     url_fdopen(&rtpctx->pb, handle);
+    } else
+        url_open_dyn_packet_buf(&rtpctx->pb, RTSP_TCP_MAX_PACKET_SIZE);
     ret = av_write_header(rtpctx);
 
     if (ret) {
+        if (handle) {
         url_fclose(rtpctx->pb);
+        } else {
+            uint8_t *ptr;
+            url_close_dyn_buf(rtpctx->pb, &ptr);
+            av_free(ptr);
+        }
         av_free(rtpctx->streams[0]);
         av_free(rtpctx);
         return NULL;
@@ -1464,11 +1479,12 @@ redirect:
         lower_transport_mask = (1 << RTSP_LOWER_TRANSPORT_NB) - 1;
 
     if (s->oformat) {
-        /* Only UDP output is supported at the moment. */
-        lower_transport_mask &= 1 << RTSP_LOWER_TRANSPORT_UDP;
+        /* Only UDP or TCP - UDP multicast isn't supported. */
+        lower_transport_mask &= (1 << RTSP_LOWER_TRANSPORT_UDP) |
+                                (1 << RTSP_LOWER_TRANSPORT_TCP);
         if (!lower_transport_mask) {
             av_log(s, AV_LOG_ERROR, "Unsupported lower transport method, "
-                                    "only UDP is supported for output.\n");
+                                    "only UDP and TCP are supported for output.\n");
             err = AVERROR(EINVAL);
             goto fail;
         }
diff --git a/libavformat/rtspenc.c b/libavformat/rtspenc.c
index cd5512fae3..5eab8000fd 100644
--- a/libavformat/rtspenc.c
+++ b/libavformat/rtspenc.c
@@ -27,6 +27,7 @@
 #endif
 #include "network.h"
 #include "rtsp.h"
+#include <libavutil/intreadwrite.h>
 
 static int rtsp_write_record(AVFormatContext *s)
 {
@@ -63,6 +64,40 @@ static int rtsp_write_header(AVFormatContext *s)
     return 0;
 }
 
+static int tcp_write_packet(AVFormatContext *s, RTSPStream *rtsp_st)
+{
+    RTSPState *rt = s->priv_data;
+    AVFormatContext *rtpctx = rtsp_st->transport_priv;
+    uint8_t *buf, *ptr;
+    int size;
+    uint8_t interleave_header[4];
+
+    size = url_close_dyn_buf(rtpctx->pb, &buf);
+    ptr = buf;
+    while (size > 4) {
+        uint32_t packet_len = AV_RB32(ptr);
+        int id;
+        ptr += 4;
+        size -= 4;
+        if (packet_len > size || packet_len < 2)
+            break;
+        if (ptr[1] >= 200 && ptr[1] <= 204)
+            id = rtsp_st->interleaved_max; /* RTCP */
+        else
+            id = rtsp_st->interleaved_min; /* RTP */
+        interleave_header[0] = '$';
+        interleave_header[1] = id;
+        AV_WB16(interleave_header + 2, packet_len);
+        url_write(rt->rtsp_hd, interleave_header, 4);
+        url_write(rt->rtsp_hd, ptr, packet_len);
+        ptr += packet_len;
+        size -= packet_len;
+    }
+    av_free(buf);
+    url_open_dyn_packet_buf(&rtpctx->pb, RTSP_TCP_MAX_PACKET_SIZE);
+    return 0;
+}
+
 static int rtsp_write_packet(AVFormatContext *s, AVPacket *pkt)
 {
     RTSPState *rt = s->priv_data;
@@ -111,7 +146,14 @@ static int rtsp_write_packet(AVFormatContext *s, AVPacket *pkt)
      * the internal stream_index = 0 becomes visible to the muxer user. */
     local_pkt = *pkt;
     local_pkt.stream_index = 0;
-    return av_write_frame(rtpctx, &local_pkt);
+    ret = av_write_frame(rtpctx, &local_pkt);
+    /* av_write_frame does all the RTP packetization. If using TCP as
+     * transport, rtpctx->pb is only a dyn_packet_buf that queues up the
+     * packets, so we need to send them out on the TCP connection separately.
+     */
+    if (!ret && rt->lower_transport == RTSP_LOWER_TRANSPORT_TCP)
+        ret = tcp_write_packet(s, rtsp_st);
+    return ret;
 }
 
 static int rtsp_write_close(AVFormatContext *s)