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udp.c
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1 /*
2  * UDP prototype streaming system
3  * Copyright (c) 2000, 2001, 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
24  * UDP protocol
25  */
26 
27 #define _BSD_SOURCE /* Needed for using struct ip_mreq with recent glibc */
28 
29 #include "avformat.h"
30 #include "avio_internal.h"
31 #include "libavutil/parseutils.h"
32 #include "libavutil/fifo.h"
33 #include "libavutil/intreadwrite.h"
34 #include "libavutil/avstring.h"
35 #include "libavutil/opt.h"
36 #include "libavutil/log.h"
37 #include "libavutil/time.h"
38 #include "internal.h"
39 #include "network.h"
40 #include "os_support.h"
41 #include "url.h"
42 
43 #if HAVE_PTHREAD_CANCEL
44 #include <pthread.h>
45 #endif
46 
47 #ifndef HAVE_PTHREAD_CANCEL
48 #define HAVE_PTHREAD_CANCEL 0
49 #endif
50 
51 #ifndef IPV6_ADD_MEMBERSHIP
52 #define IPV6_ADD_MEMBERSHIP IPV6_JOIN_GROUP
53 #define IPV6_DROP_MEMBERSHIP IPV6_LEAVE_GROUP
54 #endif
55 
56 #define UDP_TX_BUF_SIZE 32768
57 #define UDP_MAX_PKT_SIZE 65536
58 
59 typedef struct {
60  const AVClass *class;
61  int udp_fd;
62  int ttl;
69  struct sockaddr_storage dest_addr;
72 
73  /* Circular Buffer variables for use in UDP receive code */
77 #if HAVE_PTHREAD_CANCEL
78  pthread_t circular_buffer_thread;
80  pthread_cond_t cond;
81  int thread_started;
82 #endif
85  char *local_addr;
87  int timeout;
88  struct sockaddr_storage local_addr_storage;
89 } UDPContext;
90 
91 #define OFFSET(x) offsetof(UDPContext, x)
92 #define D AV_OPT_FLAG_DECODING_PARAM
93 #define E AV_OPT_FLAG_ENCODING_PARAM
94 static const AVOption options[] = {
95 {"buffer_size", "set packet buffer size in bytes", OFFSET(buffer_size), AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX, D|E },
96 {"localport", "set local port to bind to", OFFSET(local_port), AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX, D|E },
97 {"localaddr", "choose local IP address", OFFSET(local_addr), AV_OPT_TYPE_STRING, {.str = ""}, 0, 0, D|E },
98 {"pkt_size", "set size of UDP packets", OFFSET(packet_size), AV_OPT_TYPE_INT, {.i64 = 1472}, 0, INT_MAX, D|E },
99 {"reuse", "explicitly allow or disallow reusing UDP sockets", OFFSET(reuse_socket), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1, D|E },
100 {"broadcast", "explicitly allow or disallow broadcast destination", OFFSET(is_broadcast), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1, E },
101 {"ttl", "set the time to live value (for multicast only)", OFFSET(ttl), AV_OPT_TYPE_INT, {.i64 = 16}, 0, INT_MAX, E },
102 {"connect", "set if connect() should be called on socket", OFFSET(is_connected), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1, D|E },
103 /* TODO 'sources', 'block' option */
104 {"fifo_size", "set the UDP receiving circular buffer size, expressed as a number of packets with size of 188 bytes", OFFSET(circular_buffer_size), AV_OPT_TYPE_INT, {.i64 = 7*4096}, 0, INT_MAX, D },
105 {"overrun_nonfatal", "survive in case of UDP receiving circular buffer overrun", OFFSET(overrun_nonfatal), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1, D },
106 {"timeout", "set raise error timeout (only in read mode)", OFFSET(timeout), AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX, D },
107 {NULL}
108 };
109 
110 static const AVClass udp_context_class = {
111  .class_name = "udp",
112  .item_name = av_default_item_name,
113  .option = options,
114  .version = LIBAVUTIL_VERSION_INT,
115 };
116 
117 static void log_net_error(void *ctx, int level, const char* prefix)
118 {
119  char errbuf[100];
120  av_strerror(ff_neterrno(), errbuf, sizeof(errbuf));
121  av_log(ctx, level, "%s: %s\n", prefix, errbuf);
122 }
123 
124 static int udp_set_multicast_ttl(int sockfd, int mcastTTL,
125  struct sockaddr *addr)
126 {
127 #ifdef IP_MULTICAST_TTL
128  if (addr->sa_family == AF_INET) {
129  if (setsockopt(sockfd, IPPROTO_IP, IP_MULTICAST_TTL, &mcastTTL, sizeof(mcastTTL)) < 0) {
130  log_net_error(NULL, AV_LOG_ERROR, "setsockopt(IP_MULTICAST_TTL)");
131  return -1;
132  }
133  }
134 #endif
135 #if defined(IPPROTO_IPV6) && defined(IPV6_MULTICAST_HOPS)
136  if (addr->sa_family == AF_INET6) {
137  if (setsockopt(sockfd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &mcastTTL, sizeof(mcastTTL)) < 0) {
138  log_net_error(NULL, AV_LOG_ERROR, "setsockopt(IPV6_MULTICAST_HOPS)");
139  return -1;
140  }
141  }
142 #endif
143  return 0;
144 }
145 
146 static int udp_join_multicast_group(int sockfd, struct sockaddr *addr,struct sockaddr *local_addr)
147 {
148 #ifdef IP_ADD_MEMBERSHIP
149  if (addr->sa_family == AF_INET) {
150  struct ip_mreq mreq;
151 
152  mreq.imr_multiaddr.s_addr = ((struct sockaddr_in *)addr)->sin_addr.s_addr;
153  if (local_addr)
154  mreq.imr_interface= ((struct sockaddr_in *)local_addr)->sin_addr;
155  else
156  mreq.imr_interface.s_addr= INADDR_ANY;
157  if (setsockopt(sockfd, IPPROTO_IP, IP_ADD_MEMBERSHIP, (const void *)&mreq, sizeof(mreq)) < 0) {
158  log_net_error(NULL, AV_LOG_ERROR, "setsockopt(IP_ADD_MEMBERSHIP)");
159  return -1;
160  }
161  }
162 #endif
163 #if HAVE_STRUCT_IPV6_MREQ && defined(IPPROTO_IPV6)
164  if (addr->sa_family == AF_INET6) {
165  struct ipv6_mreq mreq6;
166 
167  memcpy(&mreq6.ipv6mr_multiaddr, &(((struct sockaddr_in6 *)addr)->sin6_addr), sizeof(struct in6_addr));
168  mreq6.ipv6mr_interface= 0;
169  if (setsockopt(sockfd, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &mreq6, sizeof(mreq6)) < 0) {
170  log_net_error(NULL, AV_LOG_ERROR, "setsockopt(IPV6_ADD_MEMBERSHIP)");
171  return -1;
172  }
173  }
174 #endif
175  return 0;
176 }
177 
178 static int udp_leave_multicast_group(int sockfd, struct sockaddr *addr,struct sockaddr *local_addr)
179 {
180 #ifdef IP_DROP_MEMBERSHIP
181  if (addr->sa_family == AF_INET) {
182  struct ip_mreq mreq;
183 
184  mreq.imr_multiaddr.s_addr = ((struct sockaddr_in *)addr)->sin_addr.s_addr;
185  if (local_addr)
186  mreq.imr_interface= ((struct sockaddr_in *)local_addr)->sin_addr;
187  else
188  mreq.imr_interface.s_addr= INADDR_ANY;
189  if (setsockopt(sockfd, IPPROTO_IP, IP_DROP_MEMBERSHIP, (const void *)&mreq, sizeof(mreq)) < 0) {
190  log_net_error(NULL, AV_LOG_ERROR, "setsockopt(IP_DROP_MEMBERSHIP)");
191  return -1;
192  }
193  }
194 #endif
195 #if HAVE_STRUCT_IPV6_MREQ && defined(IPPROTO_IPV6)
196  if (addr->sa_family == AF_INET6) {
197  struct ipv6_mreq mreq6;
198 
199  memcpy(&mreq6.ipv6mr_multiaddr, &(((struct sockaddr_in6 *)addr)->sin6_addr), sizeof(struct in6_addr));
200  mreq6.ipv6mr_interface= 0;
201  if (setsockopt(sockfd, IPPROTO_IPV6, IPV6_DROP_MEMBERSHIP, &mreq6, sizeof(mreq6)) < 0) {
202  log_net_error(NULL, AV_LOG_ERROR, "setsockopt(IPV6_DROP_MEMBERSHIP)");
203  return -1;
204  }
205  }
206 #endif
207  return 0;
208 }
209 
210 static struct addrinfo* udp_resolve_host(const char *hostname, int port,
211  int type, int family, int flags)
212 {
213  struct addrinfo hints = { 0 }, *res = 0;
214  int error;
215  char sport[16];
216  const char *node = 0, *service = "0";
217 
218  if (port > 0) {
219  snprintf(sport, sizeof(sport), "%d", port);
220  service = sport;
221  }
222  if ((hostname) && (hostname[0] != '\0') && (hostname[0] != '?')) {
223  node = hostname;
224  }
225  hints.ai_socktype = type;
226  hints.ai_family = family;
227  hints.ai_flags = flags;
228  if ((error = getaddrinfo(node, service, &hints, &res))) {
229  res = NULL;
230  av_log(NULL, AV_LOG_ERROR, "udp_resolve_host: %s\n", gai_strerror(error));
231  }
232 
233  return res;
234 }
235 
236 static int udp_set_multicast_sources(int sockfd, struct sockaddr *addr,
237  int addr_len, char **sources,
238  int nb_sources, int include)
239 {
240 #if HAVE_STRUCT_GROUP_SOURCE_REQ && defined(MCAST_BLOCK_SOURCE) && !defined(_WIN32)
241  /* These ones are available in the microsoft SDK, but don't seem to work
242  * as on linux, so just prefer the v4-only approach there for now. */
243  int i;
244  for (i = 0; i < nb_sources; i++) {
245  struct group_source_req mreqs;
246  int level = addr->sa_family == AF_INET ? IPPROTO_IP : IPPROTO_IPV6;
247  struct addrinfo *sourceaddr = udp_resolve_host(sources[i], 0,
248  SOCK_DGRAM, AF_UNSPEC,
249  0);
250  if (!sourceaddr)
251  return AVERROR(ENOENT);
252 
253  mreqs.gsr_interface = 0;
254  memcpy(&mreqs.gsr_group, addr, addr_len);
255  memcpy(&mreqs.gsr_source, sourceaddr->ai_addr, sourceaddr->ai_addrlen);
256  freeaddrinfo(sourceaddr);
257 
258  if (setsockopt(sockfd, level,
259  include ? MCAST_JOIN_SOURCE_GROUP : MCAST_BLOCK_SOURCE,
260  (const void *)&mreqs, sizeof(mreqs)) < 0) {
261  if (include)
262  log_net_error(NULL, AV_LOG_ERROR, "setsockopt(MCAST_JOIN_SOURCE_GROUP)");
263  else
264  log_net_error(NULL, AV_LOG_ERROR, "setsockopt(MCAST_BLOCK_SOURCE)");
265  return ff_neterrno();
266  }
267  }
268 #elif HAVE_STRUCT_IP_MREQ_SOURCE && defined(IP_BLOCK_SOURCE)
269  int i;
270  if (addr->sa_family != AF_INET) {
271  av_log(NULL, AV_LOG_ERROR,
272  "Setting multicast sources only supported for IPv4\n");
273  return AVERROR(EINVAL);
274  }
275  for (i = 0; i < nb_sources; i++) {
276  struct ip_mreq_source mreqs;
277  struct addrinfo *sourceaddr = udp_resolve_host(sources[i], 0,
278  SOCK_DGRAM, AF_UNSPEC,
279  0);
280  if (!sourceaddr)
281  return AVERROR(ENOENT);
282  if (sourceaddr->ai_addr->sa_family != AF_INET) {
283  freeaddrinfo(sourceaddr);
284  av_log(NULL, AV_LOG_ERROR, "%s is of incorrect protocol family\n",
285  sources[i]);
286  return AVERROR(EINVAL);
287  }
288 
289  mreqs.imr_multiaddr.s_addr = ((struct sockaddr_in *)addr)->sin_addr.s_addr;
290  mreqs.imr_interface.s_addr = INADDR_ANY;
291  mreqs.imr_sourceaddr.s_addr = ((struct sockaddr_in *)sourceaddr->ai_addr)->sin_addr.s_addr;
292  freeaddrinfo(sourceaddr);
293 
294  if (setsockopt(sockfd, IPPROTO_IP,
295  include ? IP_ADD_SOURCE_MEMBERSHIP : IP_BLOCK_SOURCE,
296  (const void *)&mreqs, sizeof(mreqs)) < 0) {
297  if (include)
298  log_net_error(NULL, AV_LOG_ERROR, "setsockopt(IP_ADD_SOURCE_MEMBERSHIP)");
299  else
300  log_net_error(NULL, AV_LOG_ERROR, "setsockopt(IP_BLOCK_SOURCE)");
301  return ff_neterrno();
302  }
303  }
304 #else
305  return AVERROR(ENOSYS);
306 #endif
307  return 0;
308 }
309 static int udp_set_url(struct sockaddr_storage *addr,
310  const char *hostname, int port)
311 {
312  struct addrinfo *res0;
313  int addr_len;
314 
315  res0 = udp_resolve_host(hostname, port, SOCK_DGRAM, AF_UNSPEC, 0);
316  if (!res0) return AVERROR(EIO);
317  memcpy(addr, res0->ai_addr, res0->ai_addrlen);
318  addr_len = res0->ai_addrlen;
319  freeaddrinfo(res0);
320 
321  return addr_len;
322 }
323 
324 static int udp_socket_create(UDPContext *s, struct sockaddr_storage *addr,
325  socklen_t *addr_len, const char *localaddr)
326 {
327  int udp_fd = -1;
328  struct addrinfo *res0, *res;
329  int family = AF_UNSPEC;
330 
331  if (((struct sockaddr *) &s->dest_addr)->sa_family)
332  family = ((struct sockaddr *) &s->dest_addr)->sa_family;
333  res0 = udp_resolve_host(localaddr[0] ? localaddr : NULL, s->local_port,
334  SOCK_DGRAM, family, AI_PASSIVE);
335  if (!res0)
336  goto fail;
337  for (res = res0; res; res=res->ai_next) {
338  udp_fd = ff_socket(res->ai_family, SOCK_DGRAM, 0);
339  if (udp_fd != -1) break;
340  log_net_error(NULL, AV_LOG_ERROR, "socket");
341  }
342 
343  if (udp_fd < 0)
344  goto fail;
345 
346  memcpy(addr, res->ai_addr, res->ai_addrlen);
347  *addr_len = res->ai_addrlen;
348 
349  freeaddrinfo(res0);
350 
351  return udp_fd;
352 
353  fail:
354  if (udp_fd >= 0)
355  closesocket(udp_fd);
356  if(res0)
357  freeaddrinfo(res0);
358  return -1;
359 }
360 
361 static int udp_port(struct sockaddr_storage *addr, int addr_len)
362 {
363  char sbuf[sizeof(int)*3+1];
364  int error;
365 
366  if ((error = getnameinfo((struct sockaddr *)addr, addr_len, NULL, 0, sbuf, sizeof(sbuf), NI_NUMERICSERV)) != 0) {
367  av_log(NULL, AV_LOG_ERROR, "getnameinfo: %s\n", gai_strerror(error));
368  return -1;
369  }
370 
371  return strtol(sbuf, NULL, 10);
372 }
373 
374 
375 /**
376  * If no filename is given to av_open_input_file because you want to
377  * get the local port first, then you must call this function to set
378  * the remote server address.
379  *
380  * url syntax: udp://host:port[?option=val...]
381  * option: 'ttl=n' : set the ttl value (for multicast only)
382  * 'localport=n' : set the local port
383  * 'pkt_size=n' : set max packet size
384  * 'reuse=1' : enable reusing the socket
385  * 'overrun_nonfatal=1': survive in case of circular buffer overrun
386  *
387  * @param h media file context
388  * @param uri of the remote server
389  * @return zero if no error.
390  */
391 int ff_udp_set_remote_url(URLContext *h, const char *uri)
392 {
393  UDPContext *s = h->priv_data;
394  char hostname[256], buf[10];
395  int port;
396  const char *p;
397 
398  av_url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &port, NULL, 0, uri);
399 
400  /* set the destination address */
401  s->dest_addr_len = udp_set_url(&s->dest_addr, hostname, port);
402  if (s->dest_addr_len < 0) {
403  return AVERROR(EIO);
404  }
405  s->is_multicast = ff_is_multicast_address((struct sockaddr*) &s->dest_addr);
406  p = strchr(uri, '?');
407  if (p) {
408  if (av_find_info_tag(buf, sizeof(buf), "connect", p)) {
409  int was_connected = s->is_connected;
410  s->is_connected = strtol(buf, NULL, 10);
411  if (s->is_connected && !was_connected) {
412  if (connect(s->udp_fd, (struct sockaddr *) &s->dest_addr,
413  s->dest_addr_len)) {
414  s->is_connected = 0;
415  log_net_error(h, AV_LOG_ERROR, "connect");
416  return AVERROR(EIO);
417  }
418  }
419  }
420  }
421 
422  return 0;
423 }
424 
425 /**
426  * Return the local port used by the UDP connection
427  * @param h media file context
428  * @return the local port number
429  */
431 {
432  UDPContext *s = h->priv_data;
433  return s->local_port;
434 }
435 
436 /**
437  * Return the udp file handle for select() usage to wait for several RTP
438  * streams at the same time.
439  * @param h media file context
440  */
442 {
443  UDPContext *s = h->priv_data;
444  return s->udp_fd;
445 }
446 
447 #if HAVE_PTHREAD_CANCEL
448 static void *circular_buffer_task( void *_URLContext)
449 {
450  URLContext *h = _URLContext;
451  UDPContext *s = h->priv_data;
452  int old_cancelstate;
453 
454  pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &old_cancelstate);
455  pthread_mutex_lock(&s->mutex);
456  if (ff_socket_nonblock(s->udp_fd, 0) < 0) {
457  av_log(h, AV_LOG_ERROR, "Failed to set blocking mode");
458  s->circular_buffer_error = AVERROR(EIO);
459  goto end;
460  }
461  while(1) {
462  int len;
463 
464  pthread_mutex_unlock(&s->mutex);
465  /* Blocking operations are always cancellation points;
466  see "General Information" / "Thread Cancelation Overview"
467  in Single Unix. */
468  pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, &old_cancelstate);
469  len = recv(s->udp_fd, s->tmp+4, sizeof(s->tmp)-4, 0);
470  pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &old_cancelstate);
471  pthread_mutex_lock(&s->mutex);
472  if (len < 0) {
473  if (ff_neterrno() != AVERROR(EAGAIN) && ff_neterrno() != AVERROR(EINTR)) {
475  goto end;
476  }
477  continue;
478  }
479  AV_WL32(s->tmp, len);
480 
481  if(av_fifo_space(s->fifo) < len + 4) {
482  /* No Space left */
483  if (s->overrun_nonfatal) {
484  av_log(h, AV_LOG_WARNING, "Circular buffer overrun. "
485  "Surviving due to overrun_nonfatal option\n");
486  continue;
487  } else {
488  av_log(h, AV_LOG_ERROR, "Circular buffer overrun. "
489  "To avoid, increase fifo_size URL option. "
490  "To survive in such case, use overrun_nonfatal option\n");
491  s->circular_buffer_error = AVERROR(EIO);
492  goto end;
493  }
494  }
495  av_fifo_generic_write(s->fifo, s->tmp, len+4, NULL);
496  pthread_cond_signal(&s->cond);
497  }
498 
499 end:
500  pthread_cond_signal(&s->cond);
501  pthread_mutex_unlock(&s->mutex);
502  return NULL;
503 }
504 #endif
505 
506 static int parse_source_list(char *buf, char **sources, int *num_sources,
507  int max_sources)
508 {
509  char *source_start;
510 
511  source_start = buf;
512  while (1) {
513  char *next = strchr(source_start, ',');
514  if (next)
515  *next = '\0';
516  sources[*num_sources] = av_strdup(source_start);
517  if (!sources[*num_sources])
518  return AVERROR(ENOMEM);
519  source_start = next + 1;
520  (*num_sources)++;
521  if (*num_sources >= max_sources || !next)
522  break;
523  }
524  return 0;
525 }
526 
527 /* put it in UDP context */
528 /* return non zero if error */
529 static int udp_open(URLContext *h, const char *uri, int flags)
530 {
531  char hostname[1024], localaddr[1024] = "";
532  int port, udp_fd = -1, tmp, bind_ret = -1;
533  UDPContext *s = h->priv_data;
534  int is_output;
535  const char *p;
536  char buf[256];
537  struct sockaddr_storage my_addr;
538  socklen_t len;
539  int reuse_specified = 0;
540  int i, num_include_sources = 0, num_exclude_sources = 0;
541  char *include_sources[32], *exclude_sources[32];
542 
543  h->is_streamed = 1;
544 
545  is_output = !(flags & AVIO_FLAG_READ);
546  if (!s->buffer_size) /* if not set explicitly */
547  s->buffer_size = is_output ? UDP_TX_BUF_SIZE : UDP_MAX_PKT_SIZE;
548 
549  p = strchr(uri, '?');
550  if (p) {
551  if (av_find_info_tag(buf, sizeof(buf), "reuse", p)) {
552  char *endptr = NULL;
553  s->reuse_socket = strtol(buf, &endptr, 10);
554  /* assume if no digits were found it is a request to enable it */
555  if (buf == endptr)
556  s->reuse_socket = 1;
557  reuse_specified = 1;
558  }
559  if (av_find_info_tag(buf, sizeof(buf), "overrun_nonfatal", p)) {
560  char *endptr = NULL;
561  s->overrun_nonfatal = strtol(buf, &endptr, 10);
562  /* assume if no digits were found it is a request to enable it */
563  if (buf == endptr)
564  s->overrun_nonfatal = 1;
565  if (!HAVE_PTHREAD_CANCEL)
567  "'overrun_nonfatal' option was set but it is not supported "
568  "on this build (pthread support is required)\n");
569  }
570  if (av_find_info_tag(buf, sizeof(buf), "ttl", p)) {
571  s->ttl = strtol(buf, NULL, 10);
572  }
573  if (av_find_info_tag(buf, sizeof(buf), "localport", p)) {
574  s->local_port = strtol(buf, NULL, 10);
575  }
576  if (av_find_info_tag(buf, sizeof(buf), "pkt_size", p)) {
577  s->packet_size = strtol(buf, NULL, 10);
578  }
579  if (av_find_info_tag(buf, sizeof(buf), "buffer_size", p)) {
580  s->buffer_size = strtol(buf, NULL, 10);
581  }
582  if (av_find_info_tag(buf, sizeof(buf), "connect", p)) {
583  s->is_connected = strtol(buf, NULL, 10);
584  }
585  if (av_find_info_tag(buf, sizeof(buf), "fifo_size", p)) {
586  s->circular_buffer_size = strtol(buf, NULL, 10);
587  if (!HAVE_PTHREAD_CANCEL)
589  "'circular_buffer_size' option was set but it is not supported "
590  "on this build (pthread support is required)\n");
591  }
592  if (av_find_info_tag(buf, sizeof(buf), "localaddr", p)) {
593  av_strlcpy(localaddr, buf, sizeof(localaddr));
594  }
595  if (av_find_info_tag(buf, sizeof(buf), "sources", p)) {
596  if (parse_source_list(buf, include_sources, &num_include_sources,
597  FF_ARRAY_ELEMS(include_sources)))
598  goto fail;
599  }
600  if (av_find_info_tag(buf, sizeof(buf), "block", p)) {
601  if (parse_source_list(buf, exclude_sources, &num_exclude_sources,
602  FF_ARRAY_ELEMS(exclude_sources)))
603  goto fail;
604  }
605  if (!is_output && av_find_info_tag(buf, sizeof(buf), "timeout", p))
606  s->timeout = strtol(buf, NULL, 10);
607  if (is_output && av_find_info_tag(buf, sizeof(buf), "broadcast", p))
608  s->is_broadcast = strtol(buf, NULL, 10);
609  }
610  /* handling needed to support options picking from both AVOption and URL */
611  s->circular_buffer_size *= 188;
612  if (flags & AVIO_FLAG_WRITE) {
614  } else {
616  }
617  h->rw_timeout = s->timeout;
618 
619  /* fill the dest addr */
620  av_url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &port, NULL, 0, uri);
621 
622  /* XXX: fix av_url_split */
623  if (hostname[0] == '\0' || hostname[0] == '?') {
624  /* only accepts null hostname if input */
625  if (!(flags & AVIO_FLAG_READ))
626  goto fail;
627  } else {
628  if (ff_udp_set_remote_url(h, uri) < 0)
629  goto fail;
630  }
631 
632  if ((s->is_multicast || !s->local_port) && (h->flags & AVIO_FLAG_READ))
633  s->local_port = port;
634  udp_fd = udp_socket_create(s, &my_addr, &len, localaddr[0] ? localaddr : s->local_addr);
635  if (udp_fd < 0)
636  goto fail;
637 
638  s->local_addr_storage=my_addr; //store for future multicast join
639 
640  /* Follow the requested reuse option, unless it's multicast in which
641  * case enable reuse unless explicitly disabled.
642  */
643  if (s->reuse_socket || (s->is_multicast && !reuse_specified)) {
644  s->reuse_socket = 1;
645  if (setsockopt (udp_fd, SOL_SOCKET, SO_REUSEADDR, &(s->reuse_socket), sizeof(s->reuse_socket)) != 0)
646  goto fail;
647  }
648 
649  if (s->is_broadcast) {
650 #ifdef SO_BROADCAST
651  if (setsockopt (udp_fd, SOL_SOCKET, SO_BROADCAST, &(s->is_broadcast), sizeof(s->is_broadcast)) != 0)
652 #endif
653  goto fail;
654  }
655 
656  /* If multicast, try binding the multicast address first, to avoid
657  * receiving UDP packets from other sources aimed at the same UDP
658  * port. This fails on windows. This makes sending to the same address
659  * using sendto() fail, so only do it if we're opened in read-only mode. */
660  if (s->is_multicast && !(h->flags & AVIO_FLAG_WRITE)) {
661  bind_ret = bind(udp_fd,(struct sockaddr *)&s->dest_addr, len);
662  }
663  /* bind to the local address if not multicast or if the multicast
664  * bind failed */
665  /* the bind is needed to give a port to the socket now */
666  if (bind_ret < 0 && bind(udp_fd,(struct sockaddr *)&my_addr, len) < 0) {
667  log_net_error(h, AV_LOG_ERROR, "bind failed");
668  goto fail;
669  }
670 
671  len = sizeof(my_addr);
672  getsockname(udp_fd, (struct sockaddr *)&my_addr, &len);
673  s->local_port = udp_port(&my_addr, len);
674 
675  if (s->is_multicast) {
676  if (h->flags & AVIO_FLAG_WRITE) {
677  /* output */
678  if (udp_set_multicast_ttl(udp_fd, s->ttl, (struct sockaddr *)&s->dest_addr) < 0)
679  goto fail;
680  }
681  if (h->flags & AVIO_FLAG_READ) {
682  /* input */
683  if (num_include_sources && num_exclude_sources) {
684  av_log(h, AV_LOG_ERROR, "Simultaneously including and excluding multicast sources is not supported\n");
685  goto fail;
686  }
687  if (num_include_sources) {
688  if (udp_set_multicast_sources(udp_fd, (struct sockaddr *)&s->dest_addr, s->dest_addr_len, include_sources, num_include_sources, 1) < 0)
689  goto fail;
690  } else {
691  if (udp_join_multicast_group(udp_fd, (struct sockaddr *)&s->dest_addr,(struct sockaddr *)&s->local_addr_storage) < 0)
692  goto fail;
693  }
694  if (num_exclude_sources) {
695  if (udp_set_multicast_sources(udp_fd, (struct sockaddr *)&s->dest_addr, s->dest_addr_len, exclude_sources, num_exclude_sources, 0) < 0)
696  goto fail;
697  }
698  }
699  }
700 
701  if (is_output) {
702  /* limit the tx buf size to limit latency */
703  tmp = s->buffer_size;
704  if (setsockopt(udp_fd, SOL_SOCKET, SO_SNDBUF, &tmp, sizeof(tmp)) < 0) {
705  log_net_error(h, AV_LOG_ERROR, "setsockopt(SO_SNDBUF)");
706  goto fail;
707  }
708  } else {
709  /* set udp recv buffer size to the requested value (default 64K) */
710  tmp = s->buffer_size;
711  if (setsockopt(udp_fd, SOL_SOCKET, SO_RCVBUF, &tmp, sizeof(tmp)) < 0) {
712  log_net_error(h, AV_LOG_WARNING, "setsockopt(SO_RECVBUF)");
713  }
714  len = sizeof(tmp);
715  if (getsockopt(udp_fd, SOL_SOCKET, SO_RCVBUF, &tmp, &len) < 0) {
716  log_net_error(h, AV_LOG_WARNING, "getsockopt(SO_RCVBUF)");
717  } else {
718  av_log(h, AV_LOG_DEBUG, "end receive buffer size reported is %d\n", tmp);
719  if(tmp < s->buffer_size)
720  av_log(h, AV_LOG_WARNING, "attempted to set receive buffer to size %d but it only ended up set as %d", s->buffer_size, tmp);
721  }
722 
723  /* make the socket non-blocking */
724  ff_socket_nonblock(udp_fd, 1);
725  }
726  if (s->is_connected) {
727  if (connect(udp_fd, (struct sockaddr *) &s->dest_addr, s->dest_addr_len)) {
728  log_net_error(h, AV_LOG_ERROR, "connect");
729  goto fail;
730  }
731  }
732 
733  for (i = 0; i < num_include_sources; i++)
734  av_freep(&include_sources[i]);
735  for (i = 0; i < num_exclude_sources; i++)
736  av_freep(&exclude_sources[i]);
737 
738  s->udp_fd = udp_fd;
739 
740 #if HAVE_PTHREAD_CANCEL
741  if (!is_output && s->circular_buffer_size) {
742  int ret;
743 
744  /* start the task going */
746  ret = pthread_mutex_init(&s->mutex, NULL);
747  if (ret != 0) {
748  av_log(h, AV_LOG_ERROR, "pthread_mutex_init failed : %s\n", strerror(ret));
749  goto fail;
750  }
751  ret = pthread_cond_init(&s->cond, NULL);
752  if (ret != 0) {
753  av_log(h, AV_LOG_ERROR, "pthread_cond_init failed : %s\n", strerror(ret));
754  goto cond_fail;
755  }
756  ret = pthread_create(&s->circular_buffer_thread, NULL, circular_buffer_task, h);
757  if (ret != 0) {
758  av_log(h, AV_LOG_ERROR, "pthread_create failed : %s\n", strerror(ret));
759  goto thread_fail;
760  }
761  s->thread_started = 1;
762  }
763 #endif
764 
765  return 0;
766 #if HAVE_PTHREAD_CANCEL
767  thread_fail:
768  pthread_cond_destroy(&s->cond);
769  cond_fail:
770  pthread_mutex_destroy(&s->mutex);
771 #endif
772  fail:
773  if (udp_fd >= 0)
774  closesocket(udp_fd);
775  av_fifo_freep(&s->fifo);
776  for (i = 0; i < num_include_sources; i++)
777  av_freep(&include_sources[i]);
778  for (i = 0; i < num_exclude_sources; i++)
779  av_freep(&exclude_sources[i]);
780  return AVERROR(EIO);
781 }
782 
783 static int udp_read(URLContext *h, uint8_t *buf, int size)
784 {
785  UDPContext *s = h->priv_data;
786  int ret;
787  int avail, nonblock = h->flags & AVIO_FLAG_NONBLOCK;
788 
789 #if HAVE_PTHREAD_CANCEL
790  if (s->fifo) {
791  pthread_mutex_lock(&s->mutex);
792  do {
793  avail = av_fifo_size(s->fifo);
794  if (avail) { // >=size) {
795  uint8_t tmp[4];
796 
797  av_fifo_generic_read(s->fifo, tmp, 4, NULL);
798  avail= AV_RL32(tmp);
799  if(avail > size){
800  av_log(h, AV_LOG_WARNING, "Part of datagram lost due to insufficient buffer size\n");
801  avail= size;
802  }
803 
804  av_fifo_generic_read(s->fifo, buf, avail, NULL);
805  av_fifo_drain(s->fifo, AV_RL32(tmp) - avail);
806  pthread_mutex_unlock(&s->mutex);
807  return avail;
808  } else if(s->circular_buffer_error){
809  int err = s->circular_buffer_error;
810  pthread_mutex_unlock(&s->mutex);
811  return err;
812  } else if(nonblock) {
813  pthread_mutex_unlock(&s->mutex);
814  return AVERROR(EAGAIN);
815  }
816  else {
817  /* FIXME: using the monotonic clock would be better,
818  but it does not exist on all supported platforms. */
819  int64_t t = av_gettime() + 100000;
820  struct timespec tv = { .tv_sec = t / 1000000,
821  .tv_nsec = (t % 1000000) * 1000 };
822  if (pthread_cond_timedwait(&s->cond, &s->mutex, &tv) < 0) {
823  pthread_mutex_unlock(&s->mutex);
824  return AVERROR(errno == ETIMEDOUT ? EAGAIN : errno);
825  }
826  nonblock = 1;
827  }
828  } while( 1);
829  }
830 #endif
831 
832  if (!(h->flags & AVIO_FLAG_NONBLOCK)) {
833  ret = ff_network_wait_fd(s->udp_fd, 0);
834  if (ret < 0)
835  return ret;
836  }
837  ret = recv(s->udp_fd, buf, size, 0);
838 
839  return ret < 0 ? ff_neterrno() : ret;
840 }
841 
842 static int udp_write(URLContext *h, const uint8_t *buf, int size)
843 {
844  UDPContext *s = h->priv_data;
845  int ret;
846 
847  if (!(h->flags & AVIO_FLAG_NONBLOCK)) {
848  ret = ff_network_wait_fd(s->udp_fd, 1);
849  if (ret < 0)
850  return ret;
851  }
852 
853  if (!s->is_connected) {
854  ret = sendto (s->udp_fd, buf, size, 0,
855  (struct sockaddr *) &s->dest_addr,
856  s->dest_addr_len);
857  } else
858  ret = send(s->udp_fd, buf, size, 0);
859 
860  return ret < 0 ? ff_neterrno() : ret;
861 }
862 
863 static int udp_close(URLContext *h)
864 {
865  UDPContext *s = h->priv_data;
866  int ret;
867 
868  if (s->is_multicast && (h->flags & AVIO_FLAG_READ))
869  udp_leave_multicast_group(s->udp_fd, (struct sockaddr *)&s->dest_addr,(struct sockaddr *)&s->local_addr_storage);
870  closesocket(s->udp_fd);
871 #if HAVE_PTHREAD_CANCEL
872  if (s->thread_started) {
873  pthread_cancel(s->circular_buffer_thread);
874  ret = pthread_join(s->circular_buffer_thread, NULL);
875  if (ret != 0)
876  av_log(h, AV_LOG_ERROR, "pthread_join(): %s\n", strerror(ret));
877  pthread_mutex_destroy(&s->mutex);
878  pthread_cond_destroy(&s->cond);
879  }
880 #endif
881  av_fifo_freep(&s->fifo);
882  return 0;
883 }
884 
886  .name = "udp",
887  .url_open = udp_open,
888  .url_read = udp_read,
889  .url_write = udp_write,
890  .url_close = udp_close,
891  .url_get_file_handle = udp_get_file_handle,
892  .priv_data_size = sizeof(UDPContext),
893  .priv_data_class = &udp_context_class,
895 };