libavformat/rtpproto.c

   1 /*
   2  * RTP network protocol
   3  * Copyright (c) 2002 Fabrice Bellard
   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 /**
  23  * @file libavformat/rtpproto.c
  24  * RTP protocol
  25  */
  26
  27 #include "libavutil/avstring.h"
  28 #include "avformat.h"
  29 #include "rtpdec.h"
  30
  31 #include <unistd.h>
  32 #include <stdarg.h>
  33 #include "internal.h"
  34 #include "network.h"
  35 #include "os_support.h"
  36 #include <fcntl.h>
  37 #if HAVE_SYS_SELECT_H
  38 #include <sys/select.h>
  39 #endif
  40 #include <sys/time.h>
  41
  42 #define RTP_TX_BUF_SIZE  (64 * 1024)
  43 #define RTP_RX_BUF_SIZE  (128 * 1024)
  44
  45 typedef struct RTPContext {
  46     URLContext *rtp_hd, *rtcp_hd;
  47     int rtp_fd, rtcp_fd;
  48 } RTPContext;
  49
  50 /**
  51  * If no filename is given to av_open_input_file because you want to
  52  * get the local port first, then you must call this function to set
  53  * the remote server address.
  54  *
  55  * @param s1 media file context
  56  * @param uri of the remote server
  57  * @return zero if no error.
  58  */
  59
  60 int rtp_set_remote_url(URLContext *h, const char *uri)
  61 {
  62     RTPContext *s = h->priv_data;
  63     char hostname[256];
  64     int port;
  65
  66     char buf[1024];
  67     char path[1024];
  68
  69     ff_url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &port,
  70                  path, sizeof(path), uri);
  71
  72     ff_url_join(buf, sizeof(buf), "udp", NULL, hostname, port, "%s", path);
  73     udp_set_remote_url(s->rtp_hd, buf);
  74
  75     ff_url_join(buf, sizeof(buf), "udp", NULL, hostname, port + 1, "%s", path);
  76     udp_set_remote_url(s->rtcp_hd, buf);
  77     return 0;
  78 }
  79
  80
  81 /**
  82  * add option to url of the form:
  83  * "http://host:port/path?option1=val1&option2=val2...
  84  */
  85
  86 static void url_add_option(char *buf, int buf_size, const char *fmt, ...)
  87 {
  88     char buf1[1024];
  89     va_list ap;
  90
  91     va_start(ap, fmt);
  92     if (strchr(buf, '?'))
  93         av_strlcat(buf, "&", buf_size);
  94     else
  95         av_strlcat(buf, "?", buf_size);
  96     vsnprintf(buf1, sizeof(buf1), fmt, ap);
  97     av_strlcat(buf, buf1, buf_size);
  98     va_end(ap);
  99 }
 100
 101 static void build_udp_url(char *buf, int buf_size,
 102                           const char *hostname, int port,
 103                           int local_port, int ttl,
 104                           int max_packet_size)
 105 {
 106     ff_url_join(buf, buf_size, "udp", NULL, hostname, port, NULL);
 107     if (local_port >= 0)
 108         url_add_option(buf, buf_size, "localport=%d", local_port);
 109     if (ttl >= 0)
 110         url_add_option(buf, buf_size, "ttl=%d", ttl);
 111     if (max_packet_size >=0)
 112         url_add_option(buf, buf_size, "pkt_size=%d", max_packet_size);
 113 }
 114
 115 /**
 116  * url syntax: rtp://host:port[?option=val...]
 117  * option: 'ttl=n'       : set the ttl value (for multicast only)
 118  *         'localport=n' : set the local port to n
 119  *         'pkt_size=n'  : set max packet size
 120  *
 121  */
 122
 123 static int rtp_open(URLContext *h, const char *uri, int flags)
 124 {
 125     RTPContext *s;
 126     int port, is_output, ttl, local_port, max_packet_size;
 127     char hostname[256];
 128     char buf[1024];
 129     char path[1024];
 130     const char *p;
 131
 132     is_output = (flags & URL_WRONLY);
 133
 134     s = av_mallocz(sizeof(RTPContext));
 135     if (!s)
 136         return AVERROR(ENOMEM);
 137     h->priv_data = s;
 138
 139     ff_url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &port,
 140                  path, sizeof(path), uri);
 141     /* extract parameters */
 142     ttl = -1;
 143     local_port = -1;
 144     max_packet_size = -1;
 145
 146     p = strchr(uri, '?');
 147     if (p) {
 148         if (find_info_tag(buf, sizeof(buf), "ttl", p)) {
 149             ttl = strtol(buf, NULL, 10);
 150         }
 151         if (find_info_tag(buf, sizeof(buf), "localport", p)) {
 152             local_port = strtol(buf, NULL, 10);
 153         }
 154         if (find_info_tag(buf, sizeof(buf), "pkt_size", p)) {
 155             max_packet_size = strtol(buf, NULL, 10);
 156         }
 157     }
 158
 159     build_udp_url(buf, sizeof(buf),
 160                   hostname, port, local_port, ttl, max_packet_size);
 161     if (url_open(&s->rtp_hd, buf, flags) < 0)
 162         goto fail;
 163     local_port = udp_get_local_port(s->rtp_hd);
 164     /* XXX: need to open another connection if the port is not even */
 165
 166     /* well, should suppress localport in path */
 167
 168     build_udp_url(buf, sizeof(buf),
 169                   hostname, port + 1, local_port + 1, ttl, max_packet_size);
 170     if (url_open(&s->rtcp_hd, buf, flags) < 0)
 171         goto fail;
 172
 173     /* just to ease handle access. XXX: need to suppress direct handle
 174        access */
 175     s->rtp_fd = url_get_file_handle(s->rtp_hd);
 176     s->rtcp_fd = url_get_file_handle(s->rtcp_hd);
 177
 178     h->max_packet_size = url_get_max_packet_size(s->rtp_hd);
 179     h->is_streamed = 1;
 180     return 0;
 181
 182  fail:
 183     if (s->rtp_hd)
 184         url_close(s->rtp_hd);
 185     if (s->rtcp_hd)
 186         url_close(s->rtcp_hd);
 187     av_free(s);
 188     return AVERROR(EIO);
 189 }
 190
 191 static int rtp_read(URLContext *h, uint8_t *buf, int size)
 192 {
 193     RTPContext *s = h->priv_data;
 194     struct sockaddr_in from;
 195     socklen_t from_len;
 196     int len, fd_max, n;
 197     fd_set rfds;
 198     struct timeval tv;
 199 #if 0
 200     for(;;) {
 201         from_len = sizeof(from);
 202         len = recvfrom (s->rtp_fd, buf, size, 0,
 203                         (struct sockaddr *)&from, &from_len);
 204         if (len < 0) {
 205             if (ff_neterrno() == FF_NETERROR(EAGAIN) ||
 206                 ff_neterrno() == FF_NETERROR(EINTR))
 207                 continue;
 208             return AVERROR(EIO);
 209         }
 210         break;
 211     }
 212 #else
 213     for(;;) {
 214         if (url_interrupt_cb())
 215             return AVERROR(EINTR);
 216         /* build fdset to listen to RTP and RTCP packets */
 217         FD_ZERO(&rfds);
 218         fd_max = s->rtp_fd;
 219         FD_SET(s->rtp_fd, &rfds);
 220         if (s->rtcp_fd > fd_max)
 221             fd_max = s->rtcp_fd;
 222         FD_SET(s->rtcp_fd, &rfds);
 223         tv.tv_sec = 0;
 224         tv.tv_usec = 100 * 1000;
 225         n = select(fd_max + 1, &rfds, NULL, NULL, &tv);
 226         if (n > 0) {
 227             /* first try RTCP */
 228             if (FD_ISSET(s->rtcp_fd, &rfds)) {
 229                 from_len = sizeof(from);
 230                 len = recvfrom (s->rtcp_fd, buf, size, 0,
 231                                 (struct sockaddr *)&from, &from_len);
 232                 if (len < 0) {
 233                     if (ff_neterrno() == FF_NETERROR(EAGAIN) ||
 234                         ff_neterrno() == FF_NETERROR(EINTR))
 235                         continue;
 236                     return AVERROR(EIO);
 237                 }
 238                 break;
 239             }
 240             /* then RTP */
 241             if (FD_ISSET(s->rtp_fd, &rfds)) {
 242                 from_len = sizeof(from);
 243                 len = recvfrom (s->rtp_fd, buf, size, 0,
 244                                 (struct sockaddr *)&from, &from_len);
 245                 if (len < 0) {
 246                     if (ff_neterrno() == FF_NETERROR(EAGAIN) ||
 247                         ff_neterrno() == FF_NETERROR(EINTR))
 248                         continue;
 249                     return AVERROR(EIO);
 250                 }
 251                 break;
 252             }
 253         } else if (n < 0) {
 254             if (ff_neterrno() == FF_NETERROR(EINTR))
 255                 continue;
 256             return AVERROR(EIO);
 257         }
 258     }
 259 #endif
 260     return len;
 261 }
 262
 263 static int rtp_write(URLContext *h, uint8_t *buf, int size)
 264 {
 265     RTPContext *s = h->priv_data;
 266     int ret;
 267     URLContext *hd;
 268
 269     if (buf[1] >= 200 && buf[1] <= 204) {
 270         /* RTCP payload type */
 271         hd = s->rtcp_hd;
 272     } else {
 273         /* RTP payload type */
 274         hd = s->rtp_hd;
 275     }
 276
 277     ret = url_write(hd, buf, size);
 278 #if 0
 279     {
 280         struct timespec ts;
 281         ts.tv_sec = 0;
 282         ts.tv_nsec = 10 * 1000000;
 283         nanosleep(&ts, NULL);
 284     }
 285 #endif
 286     return ret;
 287 }
 288
 289 static int rtp_close(URLContext *h)
 290 {
 291     RTPContext *s = h->priv_data;
 292
 293     url_close(s->rtp_hd);
 294     url_close(s->rtcp_hd);
 295     av_free(s);
 296     return 0;
 297 }
 298
 299 /**
 300  * Return the local port used by the RTP connection
 301  * @param s1 media file context
 302  * @return the local port number
 303  */
 304
 305 int rtp_get_local_port(URLContext *h)
 306 {
 307     RTPContext *s = h->priv_data;
 308     return udp_get_local_port(s->rtp_hd);
 309 }
 310
 311 #if (LIBAVFORMAT_VERSION_MAJOR <= 52)
 312 /**
 313  * Return the rtp and rtcp file handles for select() usage to wait for
 314  * several RTP streams at the same time.
 315  * @param h media file context
 316  */
 317
 318 void rtp_get_file_handles(URLContext *h, int *prtp_fd, int *prtcp_fd)
 319 {
 320     RTPContext *s = h->priv_data;
 321
 322     *prtp_fd = s->rtp_fd;
 323     *prtcp_fd = s->rtcp_fd;
 324 }
 325 #endif
 326
 327 static int rtp_get_file_handle(URLContext *h)
 328 {
 329     RTPContext *s = h->priv_data;
 330     return s->rtp_fd;
 331 }
 332
 333 URLProtocol rtp_protocol = {
 334     "rtp",
 335     rtp_open,
 336     rtp_read,
 337     rtp_write,
 338     NULL, /* seek */
 339     rtp_close,
 340     .url_get_file_handle = rtp_get_file_handle,
 341 };