1/*
2 * RTSP muxer
3 * Copyright (c) 2010 Martin Storsjo
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22#include "avformat.h"
23
24#include <sys/time.h>
25#if HAVE_SYS_SELECT_H
26#include <sys/select.h>
27#endif
28#include "network.h"
29#include "rtsp.h"
30#include <libavutil/intreadwrite.h>
31
32static int rtsp_write_record(AVFormatContext *s)
33{
34    RTSPState *rt = s->priv_data;
35    RTSPMessageHeader reply1, *reply = &reply1;
36    char cmd[1024];
37
38    snprintf(cmd, sizeof(cmd),
39             "Range: npt=%0.3f-\r\n",
40             (double) 0);
41    ff_rtsp_send_cmd(s, "RECORD", rt->control_uri, cmd, reply, NULL);
42    if (reply->status_code != RTSP_STATUS_OK)
43        return -1;
44    rt->state = RTSP_STATE_STREAMING;
45    return 0;
46}
47
48static int rtsp_write_header(AVFormatContext *s)
49{
50    RTSPState *rt = s->priv_data;
51    int ret;
52
53    ret = ff_rtsp_connect(s);
54    if (ret)
55        return ret;
56
57    if (rtsp_write_record(s) < 0) {
58        ff_rtsp_close_streams(s);
59        url_close(rt->rtsp_hd);
60        return AVERROR_INVALIDDATA;
61    }
62    return 0;
63}
64
65static int tcp_write_packet(AVFormatContext *s, RTSPStream *rtsp_st)
66{
67    RTSPState *rt = s->priv_data;
68    AVFormatContext *rtpctx = rtsp_st->transport_priv;
69    uint8_t *buf, *ptr;
70    int size;
71    uint8_t interleave_header[4];
72
73    size = url_close_dyn_buf(rtpctx->pb, &buf);
74    ptr = buf;
75    while (size > 4) {
76        uint32_t packet_len = AV_RB32(ptr);
77        int id;
78        ptr += 4;
79        size -= 4;
80        if (packet_len > size || packet_len < 2)
81            break;
82        if (ptr[1] >= 200 && ptr[1] <= 204)
83            id = rtsp_st->interleaved_max; /* RTCP */
84        else
85            id = rtsp_st->interleaved_min; /* RTP */
86        interleave_header[0] = '$';
87        interleave_header[1] = id;
88        AV_WB16(interleave_header + 2, packet_len);
89        url_write(rt->rtsp_hd, interleave_header, 4);
90        url_write(rt->rtsp_hd, ptr, packet_len);
91        ptr += packet_len;
92        size -= packet_len;
93    }
94    av_free(buf);
95    url_open_dyn_packet_buf(&rtpctx->pb, RTSP_TCP_MAX_PACKET_SIZE);
96    return 0;
97}
98
99static int rtsp_write_packet(AVFormatContext *s, AVPacket *pkt)
100{
101    RTSPState *rt = s->priv_data;
102    RTSPStream *rtsp_st;
103    fd_set rfds;
104    int n, tcp_fd;
105    struct timeval tv;
106    AVFormatContext *rtpctx;
107    AVPacket local_pkt;
108    int ret;
109
110    tcp_fd = url_get_file_handle(rt->rtsp_hd);
111
112    while (1) {
113        FD_ZERO(&rfds);
114        FD_SET(tcp_fd, &rfds);
115        tv.tv_sec = 0;
116        tv.tv_usec = 0;
117        n = select(tcp_fd + 1, &rfds, NULL, NULL, &tv);
118        if (n <= 0)
119            break;
120        if (FD_ISSET(tcp_fd, &rfds)) {
121            RTSPMessageHeader reply;
122
123            /* Don't let ff_rtsp_read_reply handle interleaved packets,
124             * since it would block and wait for an RTSP reply on the socket
125             * (which may not be coming any time soon) if it handles
126             * interleaved packets internally. */
127            ret = ff_rtsp_read_reply(s, &reply, NULL, 1);
128            if (ret < 0)
129                return AVERROR(EPIPE);
130            if (ret == 1)
131                ff_rtsp_skip_packet(s);
132            /* XXX: parse message */
133            if (rt->state != RTSP_STATE_STREAMING)
134                return AVERROR(EPIPE);
135        }
136    }
137
138    if (pkt->stream_index < 0 || pkt->stream_index >= rt->nb_rtsp_streams)
139        return AVERROR_INVALIDDATA;
140    rtsp_st = rt->rtsp_streams[pkt->stream_index];
141    rtpctx = rtsp_st->transport_priv;
142
143    /* Use a local packet for writing to the chained muxer, otherwise
144     * the internal stream_index = 0 becomes visible to the muxer user. */
145    local_pkt = *pkt;
146    local_pkt.stream_index = 0;
147    ret = av_write_frame(rtpctx, &local_pkt);
148    /* av_write_frame does all the RTP packetization. If using TCP as
149     * transport, rtpctx->pb is only a dyn_packet_buf that queues up the
150     * packets, so we need to send them out on the TCP connection separately.
151     */
152    if (!ret && rt->lower_transport == RTSP_LOWER_TRANSPORT_TCP)
153        ret = tcp_write_packet(s, rtsp_st);
154    return ret;
155}
156
157static int rtsp_write_close(AVFormatContext *s)
158{
159    RTSPState *rt = s->priv_data;
160
161    ff_rtsp_send_cmd_async(s, "TEARDOWN", rt->control_uri, NULL);
162
163    ff_rtsp_close_streams(s);
164    url_close(rt->rtsp_hd);
165    ff_network_close();
166    return 0;
167}
168
169AVOutputFormat rtsp_muxer = {
170    "rtsp",
171    NULL_IF_CONFIG_SMALL("RTSP output format"),
172    NULL,
173    NULL,
174    sizeof(RTSPState),
175    CODEC_ID_PCM_MULAW,
176    CODEC_ID_NONE,
177    rtsp_write_header,
178    rtsp_write_packet,
179    rtsp_write_close,
180    .flags = AVFMT_NOFILE | AVFMT_GLOBALHEADER,
181};
182
183