dac5273a80788659ed0fc6ac44007f76bd150500
[libav.git] / libav / rtpproto.c
1 /*
2 * RTP network protocol
3 * Copyright (c) 2002 Fabrice Bellard.
4 *
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
9 *
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
14 *
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 */
19 #include "avformat.h"
20
21 #include <unistd.h>
22 #include <stdarg.h>
23 #include <sys/types.h>
24 #include <sys/socket.h>
25 #include <netinet/in.h>
26 #include <arpa/inet.h>
27 #include <netdb.h>
28 #include <fcntl.h>
29
30 #define RTP_TX_BUF_SIZE (64 * 1024)
31 #define RTP_RX_BUF_SIZE (128 * 1024)
32
33 typedef struct RTPContext {
34 URLContext *rtp_hd, *rtcp_hd;
35 int rtp_fd, rtcp_fd;
36 } RTPContext;
37
38 /**
39 * If no filename is given to av_open_input_file because you want to
40 * get the local port first, then you must call this function to set
41 * the remote server address.
42 *
43 * @param s1 media file context
44 * @param uri of the remote server
45 * @return zero if no error.
46 */
47 int rtp_set_remote_url(URLContext *h, const char *uri)
48 {
49 RTPContext *s = h->priv_data;
50 char hostname[256];
51 int port;
52
53 char buf[1024];
54 char path[1024];
55
56 url_split(NULL, 0, hostname, sizeof(hostname), &port,
57 path, sizeof(path), uri);
58
59 snprintf(buf, sizeof(buf), "udp://%s:%d%s", hostname, port, path);
60 udp_set_remote_url(s->rtp_hd, buf);
61
62 snprintf(buf, sizeof(buf), "udp://%s:%d%s", hostname, port + 1, path);
63 udp_set_remote_url(s->rtcp_hd, buf);
64 return 0;
65 }
66
67
68 /* add option to url of the form:
69 "http://host:port/path?option1=val1&option2=val2... */
70 void url_add_option(char *buf, int buf_size, const char *fmt, ...)
71 {
72 char buf1[1024];
73 va_list ap;
74
75 va_start(ap, fmt);
76 if (strchr(buf, '?'))
77 pstrcat(buf, buf_size, "&");
78 else
79 pstrcat(buf, buf_size, "?");
80 vsnprintf(buf1, sizeof(buf1), fmt, ap);
81 pstrcat(buf, buf_size, buf1);
82 va_end(ap);
83 }
84
85 void build_udp_url(char *buf, int buf_size,
86 const char *hostname, int port,
87 int local_port, int multicast, int ttl)
88 {
89 snprintf(buf, buf_size, "udp://%s:%d", hostname, port);
90 if (local_port >= 0)
91 url_add_option(buf, buf_size, "localport=%d", local_port);
92 if (multicast)
93 url_add_option(buf, buf_size, "multicast=1", multicast);
94 if (ttl >= 0)
95 url_add_option(buf, buf_size, "ttl=%d", ttl);
96 }
97
98 /*
99 * url syntax: rtp://host:port[?option=val...]
100 * option: 'multicast=1' : enable multicast
101 * 'ttl=n' : set the ttl value (for multicast only)
102 * 'localport=n' : set the local port to n
103 *
104 */
105 static int rtp_open(URLContext *h, const char *uri, int flags)
106 {
107 RTPContext *s;
108 int port, is_output, is_multicast, ttl, local_port;
109 char hostname[256];
110 char buf[1024];
111 char path[1024];
112 const char *p;
113
114 is_output = (flags & URL_WRONLY);
115
116 s = av_mallocz(sizeof(RTPContext));
117 if (!s)
118 return -ENOMEM;
119 h->priv_data = s;
120
121 url_split(NULL, 0, hostname, sizeof(hostname), &port,
122 path, sizeof(path), uri);
123 /* extract parameters */
124 is_multicast = 0;
125 ttl = -1;
126 local_port = -1;
127 p = strchr(uri, '?');
128 if (p) {
129 is_multicast = find_info_tag(buf, sizeof(buf), "multicast", p);
130 if (find_info_tag(buf, sizeof(buf), "ttl", p)) {
131 ttl = strtol(buf, NULL, 10);
132 }
133 if (find_info_tag(buf, sizeof(buf), "localport", p)) {
134 local_port = strtol(buf, NULL, 10);
135 }
136 }
137
138 build_udp_url(buf, sizeof(buf),
139 hostname, port, local_port, is_multicast, ttl);
140 if (url_open(&s->rtp_hd, buf, flags) < 0)
141 goto fail;
142 local_port = udp_get_local_port(s->rtp_hd);
143 /* XXX: need to open another connexion if the port is not even */
144
145 /* well, should suppress localport in path */
146
147 build_udp_url(buf, sizeof(buf),
148 hostname, port + 1, local_port + 1, is_multicast, ttl);
149 if (url_open(&s->rtcp_hd, buf, flags) < 0)
150 goto fail;
151
152 /* just to ease handle access. XXX: need to suppress direct handle
153 access */
154 s->rtp_fd = udp_get_file_handle(s->rtp_hd);
155 s->rtcp_fd = udp_get_file_handle(s->rtcp_hd);
156
157 h->max_packet_size = url_get_max_packet_size(s->rtp_hd);
158 h->is_streamed = 1;
159 return 0;
160
161 fail:
162 if (s->rtp_hd)
163 url_close(s->rtp_hd);
164 if (s->rtcp_hd)
165 url_close(s->rtcp_hd);
166 av_free(s);
167 return -EIO;
168 }
169
170 static int rtp_read(URLContext *h, UINT8 *buf, int size)
171 {
172 RTPContext *s = h->priv_data;
173 struct sockaddr_in from;
174 int from_len, len, fd_max, n;
175 fd_set rfds;
176 #if 0
177 for(;;) {
178 from_len = sizeof(from);
179 len = recvfrom (s->rtp_fd, buf, size, 0,
180 (struct sockaddr *)&from, &from_len);
181 if (len < 0) {
182 if (errno == EAGAIN || errno == EINTR)
183 continue;
184 return -EIO;
185 }
186 break;
187 }
188 #else
189 for(;;) {
190 /* build fdset to listen to RTP and RTCP packets */
191 FD_ZERO(&rfds);
192 fd_max = s->rtp_fd;
193 FD_SET(s->rtp_fd, &rfds);
194 if (s->rtcp_fd > fd_max)
195 fd_max = s->rtcp_fd;
196 FD_SET(s->rtcp_fd, &rfds);
197 n = select(fd_max + 1, &rfds, NULL, NULL, NULL);
198 if (n > 0) {
199 /* first try RTCP */
200 if (FD_ISSET(s->rtcp_fd, &rfds)) {
201 from_len = sizeof(from);
202 len = recvfrom (s->rtcp_fd, buf, size, 0,
203 (struct sockaddr *)&from, &from_len);
204 if (len < 0) {
205 if (errno == EAGAIN || errno == EINTR)
206 continue;
207 return -EIO;
208 }
209 break;
210 }
211 /* then RTP */
212 if (FD_ISSET(s->rtp_fd, &rfds)) {
213 from_len = sizeof(from);
214 len = recvfrom (s->rtp_fd, buf, size, 0,
215 (struct sockaddr *)&from, &from_len);
216 if (len < 0) {
217 if (errno == EAGAIN || errno == EINTR)
218 continue;
219 return -EIO;
220 }
221 break;
222 }
223 }
224 }
225 #endif
226 return len;
227 }
228
229 static int rtp_write(URLContext *h, UINT8 *buf, int size)
230 {
231 RTPContext *s = h->priv_data;
232 int ret;
233 URLContext *hd;
234
235 if (buf[1] >= 200 && buf[1] <= 204) {
236 /* RTCP payload type */
237 hd = s->rtcp_hd;
238 } else {
239 /* RTP payload type */
240 hd = s->rtp_hd;
241 }
242
243 ret = url_write(hd, buf, size);
244 #if 0
245 {
246 struct timespec ts;
247 ts.tv_sec = 0;
248 ts.tv_nsec = 10 * 1000000;
249 nanosleep(&ts, NULL);
250 }
251 #endif
252 return ret;
253 }
254
255 static int rtp_close(URLContext *h)
256 {
257 RTPContext *s = h->priv_data;
258
259 url_close(s->rtp_hd);
260 url_close(s->rtcp_hd);
261 av_free(s);
262 return 0;
263 }
264
265 /**
266 * Return the local port used by the RTP connexion
267 * @param s1 media file context
268 * @return the local port number
269 */
270 int rtp_get_local_port(URLContext *h)
271 {
272 RTPContext *s = h->priv_data;
273 return udp_get_local_port(s->rtp_hd);
274 }
275
276 /**
277 * Return the rtp and rtcp file handles for select() usage to wait for several RTP
278 * streams at the same time.
279 * @param h media file context
280 */
281 void rtp_get_file_handles(URLContext *h, int *prtp_fd, int *prtcp_fd)
282 {
283 RTPContext *s = h->priv_data;
284
285 *prtp_fd = s->rtp_fd;
286 *prtcp_fd = s->rtcp_fd;
287 }
288
289 URLProtocol rtp_protocol = {
290 "rtp",
291 rtp_open,
292 rtp_read,
293 rtp_write,
294 NULL, /* seek */
295 rtp_close,
296 };