• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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 _DEFAULT_SOURCE
28 #define _BSD_SOURCE     /* Needed for using struct ip_mreq with recent glibc */
29 
30 #include "avformat.h"
31 #include "avio_internal.h"
32 #include "libavutil/avassert.h"
33 #include "libavutil/parseutils.h"
34 #include "libavutil/fifo.h"
35 #include "libavutil/intreadwrite.h"
36 #include "libavutil/avstring.h"
37 #include "libavutil/opt.h"
38 #include "libavutil/log.h"
39 #include "libavutil/time.h"
40 #include "internal.h"
41 #include "network.h"
42 #include "os_support.h"
43 #include "url.h"
44 #include "ip.h"
45 
46 #ifdef __APPLE__
47 #include "TargetConditionals.h"
48 #endif
49 
50 #if HAVE_UDPLITE_H
51 #include "udplite.h"
52 #else
53 /* On many Linux systems, udplite.h is missing but the kernel supports UDP-Lite.
54  * So, we provide a fallback here.
55  */
56 #define UDPLITE_SEND_CSCOV                               10
57 #define UDPLITE_RECV_CSCOV                               11
58 #endif
59 
60 #ifndef IPPROTO_UDPLITE
61 #define IPPROTO_UDPLITE                                  136
62 #endif
63 
64 #if HAVE_W32THREADS
65 #undef HAVE_PTHREAD_CANCEL
66 #define HAVE_PTHREAD_CANCEL 1
67 #endif
68 
69 #if HAVE_PTHREAD_CANCEL
70 #include "libavutil/thread.h"
71 #endif
72 
73 #ifndef IPV6_ADD_MEMBERSHIP
74 #define IPV6_ADD_MEMBERSHIP IPV6_JOIN_GROUP
75 #define IPV6_DROP_MEMBERSHIP IPV6_LEAVE_GROUP
76 #endif
77 
78 #define UDP_TX_BUF_SIZE 32768
79 #define UDP_RX_BUF_SIZE 393216
80 #define UDP_MAX_PKT_SIZE 65536
81 #define UDP_HEADER_SIZE 8
82 
83 typedef struct UDPContext {
84     const AVClass *class;
85     int udp_fd;
86     int ttl;
87     int udplite_coverage;
88     int buffer_size;
89     int pkt_size;
90     int is_multicast;
91     int is_broadcast;
92     int local_port;
93     int reuse_socket;
94     int overrun_nonfatal;
95     struct sockaddr_storage dest_addr;
96     int dest_addr_len;
97     int is_connected;
98 
99     /* Circular Buffer variables for use in UDP receive code */
100     int circular_buffer_size;
101     AVFifo *fifo;
102     int circular_buffer_error;
103     int64_t bitrate; /* number of bits to send per second */
104     int64_t burst_bits;
105     int close_req;
106 #if HAVE_PTHREAD_CANCEL
107     pthread_t circular_buffer_thread;
108     pthread_mutex_t mutex;
109     pthread_cond_t cond;
110     int thread_started;
111 #endif
112     uint8_t tmp[UDP_MAX_PKT_SIZE+4];
113     int remaining_in_dg;
114     char *localaddr;
115     int timeout;
116     struct sockaddr_storage local_addr_storage;
117     char *sources;
118     char *block;
119     IPSourceFilters filters;
120 } UDPContext;
121 
122 #define OFFSET(x) offsetof(UDPContext, x)
123 #define D AV_OPT_FLAG_DECODING_PARAM
124 #define E AV_OPT_FLAG_ENCODING_PARAM
125 static const AVOption options[] = {
126     { "buffer_size",    "System data size (in bytes)",                     OFFSET(buffer_size),    AV_OPT_TYPE_INT,    { .i64 = -1 },    -1, INT_MAX, .flags = D|E },
127     { "bitrate",        "Bits to send per second",                         OFFSET(bitrate),        AV_OPT_TYPE_INT64,  { .i64 = 0  },     0, INT64_MAX, .flags = E },
128     { "burst_bits",     "Max length of bursts in bits (when using bitrate)", OFFSET(burst_bits),   AV_OPT_TYPE_INT64,  { .i64 = 0  },     0, INT64_MAX, .flags = E },
129     { "localport",      "Local port",                                      OFFSET(local_port),     AV_OPT_TYPE_INT,    { .i64 = -1 },    -1, INT_MAX, D|E },
130     { "local_port",     "Local port",                                      OFFSET(local_port),     AV_OPT_TYPE_INT,    { .i64 = -1 },    -1, INT_MAX, .flags = D|E },
131     { "localaddr",      "Local address",                                   OFFSET(localaddr),      AV_OPT_TYPE_STRING, { .str = NULL },               .flags = D|E },
132     { "udplite_coverage", "choose UDPLite head size which should be validated by checksum", OFFSET(udplite_coverage), AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX, D|E },
133     { "pkt_size",       "Maximum UDP packet size",                         OFFSET(pkt_size),       AV_OPT_TYPE_INT,    { .i64 = 1472 },  -1, INT_MAX, .flags = D|E },
134     { "reuse",          "explicitly allow reusing UDP sockets",            OFFSET(reuse_socket),   AV_OPT_TYPE_BOOL,   { .i64 = -1 },    -1, 1,       D|E },
135     { "reuse_socket",   "explicitly allow reusing UDP sockets",            OFFSET(reuse_socket),   AV_OPT_TYPE_BOOL,   { .i64 = -1 },    -1, 1,       .flags = D|E },
136     { "broadcast", "explicitly allow or disallow broadcast destination",   OFFSET(is_broadcast),   AV_OPT_TYPE_BOOL,   { .i64 = 0  },     0, 1,       E },
137     { "ttl",            "Time to live (multicast only)",                   OFFSET(ttl),            AV_OPT_TYPE_INT,    { .i64 = 16 },     0, 255,     E },
138     { "connect",        "set if connect() should be called on socket",     OFFSET(is_connected),   AV_OPT_TYPE_BOOL,   { .i64 =  0 },     0, 1,       .flags = D|E },
139     { "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 },
140     { "overrun_nonfatal", "survive in case of UDP receiving circular buffer overrun", OFFSET(overrun_nonfatal), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1,    D },
141     { "timeout",        "set raise error timeout, in microseconds (only in read mode)",OFFSET(timeout),         AV_OPT_TYPE_INT,  {.i64 = 0}, 0, INT_MAX, D },
142     { "sources",        "Source list",                                     OFFSET(sources),        AV_OPT_TYPE_STRING, { .str = NULL },               .flags = D|E },
143     { "block",          "Block list",                                      OFFSET(block),          AV_OPT_TYPE_STRING, { .str = NULL },               .flags = D|E },
144     { NULL }
145 };
146 
147 static const AVClass udp_class = {
148     .class_name = "udp",
149     .item_name  = av_default_item_name,
150     .option     = options,
151     .version    = LIBAVUTIL_VERSION_INT,
152 };
153 
154 static const AVClass udplite_context_class = {
155     .class_name     = "udplite",
156     .item_name      = av_default_item_name,
157     .option         = options,
158     .version        = LIBAVUTIL_VERSION_INT,
159 };
160 
udp_set_multicast_ttl(int sockfd,int mcastTTL,struct sockaddr * addr,void * logctx)161 static int udp_set_multicast_ttl(int sockfd, int mcastTTL,
162                                  struct sockaddr *addr,
163                                  void *logctx)
164 {
165     int protocol, cmd;
166 
167     /* There is some confusion in the world whether IP_MULTICAST_TTL
168      * takes a byte or an int as an argument.
169      * BSD seems to indicate byte so we are going with that and use
170      * int and fall back to byte to be safe */
171     switch (addr->sa_family) {
172 #ifdef IP_MULTICAST_TTL
173         case AF_INET:
174             protocol = IPPROTO_IP;
175             cmd      = IP_MULTICAST_TTL;
176             break;
177 #endif
178 #ifdef IPV6_MULTICAST_HOPS
179         case AF_INET6:
180             protocol = IPPROTO_IPV6;
181             cmd      = IPV6_MULTICAST_HOPS;
182             break;
183 #endif
184         default:
185             return 0;
186     }
187 
188     if (setsockopt(sockfd, protocol, cmd, &mcastTTL, sizeof(mcastTTL)) < 0) {
189         /* BSD compatibility */
190         unsigned char ttl = (unsigned char) mcastTTL;
191 
192         ff_log_net_error(logctx, AV_LOG_DEBUG, "setsockopt(IPV4/IPV6 MULTICAST TTL)");
193         if (setsockopt(sockfd, protocol, cmd, &ttl, sizeof(ttl)) < 0) {
194             ff_log_net_error(logctx, AV_LOG_ERROR, "setsockopt(IPV4/IPV6 MULTICAST TTL)");
195             return ff_neterrno();
196         }
197     }
198 
199     return 0;
200 }
201 
udp_join_multicast_group(int sockfd,struct sockaddr * addr,struct sockaddr * local_addr,void * logctx)202 static int udp_join_multicast_group(int sockfd, struct sockaddr *addr,
203                                     struct sockaddr *local_addr, void *logctx)
204 {
205 #ifdef IP_ADD_MEMBERSHIP
206     if (addr->sa_family == AF_INET) {
207         struct ip_mreq mreq;
208 
209         mreq.imr_multiaddr.s_addr = ((struct sockaddr_in *)addr)->sin_addr.s_addr;
210         if (local_addr)
211             mreq.imr_interface= ((struct sockaddr_in *)local_addr)->sin_addr;
212         else
213             mreq.imr_interface.s_addr = INADDR_ANY;
214         if (setsockopt(sockfd, IPPROTO_IP, IP_ADD_MEMBERSHIP, (const void *)&mreq, sizeof(mreq)) < 0) {
215             ff_log_net_error(logctx, AV_LOG_ERROR, "setsockopt(IP_ADD_MEMBERSHIP)");
216             return ff_neterrno();
217         }
218     }
219 #endif
220 #if HAVE_STRUCT_IPV6_MREQ && defined(IPPROTO_IPV6)
221     if (addr->sa_family == AF_INET6) {
222         struct ipv6_mreq mreq6;
223 
224         memcpy(&mreq6.ipv6mr_multiaddr, &(((struct sockaddr_in6 *)addr)->sin6_addr), sizeof(struct in6_addr));
225         //TODO: Interface index should be looked up from local_addr
226         mreq6.ipv6mr_interface = 0;
227         if (setsockopt(sockfd, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &mreq6, sizeof(mreq6)) < 0) {
228             ff_log_net_error(logctx, AV_LOG_ERROR, "setsockopt(IPV6_ADD_MEMBERSHIP)");
229             return ff_neterrno();
230         }
231     }
232 #endif
233     return 0;
234 }
235 
udp_leave_multicast_group(int sockfd,struct sockaddr * addr,struct sockaddr * local_addr,void * logctx)236 static int udp_leave_multicast_group(int sockfd, struct sockaddr *addr,
237                                      struct sockaddr *local_addr, void *logctx)
238 {
239 #ifdef IP_DROP_MEMBERSHIP
240     if (addr->sa_family == AF_INET) {
241         struct ip_mreq mreq;
242 
243         mreq.imr_multiaddr.s_addr = ((struct sockaddr_in *)addr)->sin_addr.s_addr;
244         if (local_addr)
245             mreq.imr_interface = ((struct sockaddr_in *)local_addr)->sin_addr;
246         else
247             mreq.imr_interface.s_addr = INADDR_ANY;
248         if (setsockopt(sockfd, IPPROTO_IP, IP_DROP_MEMBERSHIP, (const void *)&mreq, sizeof(mreq)) < 0) {
249             ff_log_net_error(logctx, AV_LOG_ERROR, "setsockopt(IP_DROP_MEMBERSHIP)");
250             return -1;
251         }
252     }
253 #endif
254 #if HAVE_STRUCT_IPV6_MREQ && defined(IPPROTO_IPV6)
255     if (addr->sa_family == AF_INET6) {
256         struct ipv6_mreq mreq6;
257 
258         memcpy(&mreq6.ipv6mr_multiaddr, &(((struct sockaddr_in6 *)addr)->sin6_addr), sizeof(struct in6_addr));
259         //TODO: Interface index should be looked up from local_addr
260         mreq6.ipv6mr_interface = 0;
261         if (setsockopt(sockfd, IPPROTO_IPV6, IPV6_DROP_MEMBERSHIP, &mreq6, sizeof(mreq6)) < 0) {
262             ff_log_net_error(logctx, AV_LOG_ERROR, "setsockopt(IPV6_DROP_MEMBERSHIP)");
263             return -1;
264         }
265     }
266 #endif
267     return 0;
268 }
269 
udp_set_multicast_sources(URLContext * h,int sockfd,struct sockaddr * addr,int addr_len,struct sockaddr_storage * local_addr,struct sockaddr_storage * sources,int nb_sources,int include)270 static int udp_set_multicast_sources(URLContext *h,
271                                      int sockfd, struct sockaddr *addr,
272                                      int addr_len, struct sockaddr_storage *local_addr,
273                                      struct sockaddr_storage *sources,
274                                      int nb_sources, int include)
275 {
276     int i;
277     if (addr->sa_family != AF_INET) {
278 #if HAVE_STRUCT_GROUP_SOURCE_REQ && defined(MCAST_BLOCK_SOURCE)
279         /* For IPv4 prefer the old approach, as that alone works reliably on
280          * Windows and it also supports supplying the interface based on its
281          * address. */
282         int i;
283         for (i = 0; i < nb_sources; i++) {
284             struct group_source_req mreqs;
285             int level = addr->sa_family == AF_INET ? IPPROTO_IP : IPPROTO_IPV6;
286 
287             //TODO: Interface index should be looked up from local_addr
288             mreqs.gsr_interface = 0;
289             memcpy(&mreqs.gsr_group, addr, addr_len);
290             memcpy(&mreqs.gsr_source, &sources[i], sizeof(*sources));
291 
292             if (setsockopt(sockfd, level,
293                            include ? MCAST_JOIN_SOURCE_GROUP : MCAST_BLOCK_SOURCE,
294                            (const void *)&mreqs, sizeof(mreqs)) < 0) {
295                 if (include)
296                     ff_log_net_error(h, AV_LOG_ERROR, "setsockopt(MCAST_JOIN_SOURCE_GROUP)");
297                 else
298                     ff_log_net_error(h, AV_LOG_ERROR, "setsockopt(MCAST_BLOCK_SOURCE)");
299                 return ff_neterrno();
300             }
301         }
302         return 0;
303 #else
304         av_log(h, AV_LOG_ERROR,
305                "Setting multicast sources only supported for IPv4\n");
306         return AVERROR(EINVAL);
307 #endif
308     }
309 #if HAVE_STRUCT_IP_MREQ_SOURCE && defined(IP_BLOCK_SOURCE)
310     for (i = 0; i < nb_sources; i++) {
311         struct ip_mreq_source mreqs;
312         if (sources[i].ss_family != AF_INET) {
313             av_log(h, AV_LOG_ERROR, "Source/block address %d is of incorrect protocol family\n", i + 1);
314             return AVERROR(EINVAL);
315         }
316 
317         mreqs.imr_multiaddr.s_addr = ((struct sockaddr_in *)addr)->sin_addr.s_addr;
318         if (local_addr)
319             mreqs.imr_interface = ((struct sockaddr_in *)local_addr)->sin_addr;
320         else
321             mreqs.imr_interface.s_addr = INADDR_ANY;
322         mreqs.imr_sourceaddr.s_addr = ((struct sockaddr_in *)&sources[i])->sin_addr.s_addr;
323 
324         if (setsockopt(sockfd, IPPROTO_IP,
325                        include ? IP_ADD_SOURCE_MEMBERSHIP : IP_BLOCK_SOURCE,
326                        (const void *)&mreqs, sizeof(mreqs)) < 0) {
327             if (include)
328                 ff_log_net_error(h, AV_LOG_ERROR, "setsockopt(IP_ADD_SOURCE_MEMBERSHIP)");
329             else
330                 ff_log_net_error(h, AV_LOG_ERROR, "setsockopt(IP_BLOCK_SOURCE)");
331             return ff_neterrno();
332         }
333     }
334 #else
335     return AVERROR(ENOSYS);
336 #endif
337     return 0;
338 }
udp_set_url(URLContext * h,struct sockaddr_storage * addr,const char * hostname,int port)339 static int udp_set_url(URLContext *h,
340                        struct sockaddr_storage *addr,
341                        const char *hostname, int port)
342 {
343     struct addrinfo *res0;
344     int addr_len;
345 
346     res0 = ff_ip_resolve_host(h, hostname, port, SOCK_DGRAM, AF_UNSPEC, 0);
347     if (!res0) return AVERROR(EIO);
348     memcpy(addr, res0->ai_addr, res0->ai_addrlen);
349     addr_len = res0->ai_addrlen;
350     freeaddrinfo(res0);
351 
352     return addr_len;
353 }
354 
udp_socket_create(URLContext * h,struct sockaddr_storage * addr,socklen_t * addr_len,const char * localaddr)355 static int udp_socket_create(URLContext *h, struct sockaddr_storage *addr,
356                              socklen_t *addr_len, const char *localaddr)
357 {
358     UDPContext *s = h->priv_data;
359     int udp_fd = -1;
360     struct addrinfo *res0, *res;
361     int family = AF_UNSPEC;
362 
363     if (((struct sockaddr *) &s->dest_addr)->sa_family)
364         family = ((struct sockaddr *) &s->dest_addr)->sa_family;
365     res0 = ff_ip_resolve_host(h, (localaddr && localaddr[0]) ? localaddr : NULL,
366                             s->local_port,
367                             SOCK_DGRAM, family, AI_PASSIVE);
368     if (!res0)
369         goto fail;
370     for (res = res0; res; res=res->ai_next) {
371         if (s->udplite_coverage)
372             udp_fd = ff_socket(res->ai_family, SOCK_DGRAM, IPPROTO_UDPLITE, h);
373         else
374             udp_fd = ff_socket(res->ai_family, SOCK_DGRAM, 0, h);
375         if (udp_fd != -1) break;
376         ff_log_net_error(h, AV_LOG_ERROR, "socket");
377     }
378 
379     if (udp_fd < 0)
380         goto fail;
381 
382     memcpy(addr, res->ai_addr, res->ai_addrlen);
383     *addr_len = res->ai_addrlen;
384 
385     freeaddrinfo(res0);
386 
387     return udp_fd;
388 
389  fail:
390     if (udp_fd >= 0)
391         closesocket(udp_fd);
392     if(res0)
393         freeaddrinfo(res0);
394     return -1;
395 }
396 
udp_port(struct sockaddr_storage * addr,int addr_len)397 static int udp_port(struct sockaddr_storage *addr, int addr_len)
398 {
399     char sbuf[sizeof(int)*3+1];
400     int error;
401 
402     if ((error = getnameinfo((struct sockaddr *)addr, addr_len, NULL, 0,  sbuf, sizeof(sbuf), NI_NUMERICSERV)) != 0) {
403         av_log(NULL, AV_LOG_ERROR, "getnameinfo: %s\n", gai_strerror(error));
404         return -1;
405     }
406 
407     return strtol(sbuf, NULL, 10);
408 }
409 
410 
411 /**
412  * If no filename is given to av_open_input_file because you want to
413  * get the local port first, then you must call this function to set
414  * the remote server address.
415  *
416  * url syntax: udp://host:port[?option=val...]
417  * option: 'ttl=n'       : set the ttl value (for multicast only)
418  *         'localport=n' : set the local port
419  *         'pkt_size=n'  : set max packet size
420  *         'reuse=1'     : enable reusing the socket
421  *         'overrun_nonfatal=1': survive in case of circular buffer overrun
422  *
423  * @param h media file context
424  * @param uri of the remote server
425  * @return zero if no error.
426  */
ff_udp_set_remote_url(URLContext * h,const char * uri)427 int ff_udp_set_remote_url(URLContext *h, const char *uri)
428 {
429     UDPContext *s = h->priv_data;
430     char hostname[256], buf[10];
431     int port;
432     const char *p;
433 
434     av_url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &port, NULL, 0, uri);
435 
436     /* set the destination address */
437     s->dest_addr_len = udp_set_url(h, &s->dest_addr, hostname, port);
438     if (s->dest_addr_len < 0) {
439         return AVERROR(EIO);
440     }
441     s->is_multicast = ff_is_multicast_address((struct sockaddr*) &s->dest_addr);
442     p = strchr(uri, '?');
443     if (p) {
444         if (av_find_info_tag(buf, sizeof(buf), "connect", p)) {
445             int was_connected = s->is_connected;
446             s->is_connected = strtol(buf, NULL, 10);
447             if (s->is_connected && !was_connected) {
448                 if (connect(s->udp_fd, (struct sockaddr *) &s->dest_addr,
449                             s->dest_addr_len)) {
450                     s->is_connected = 0;
451                     ff_log_net_error(h, AV_LOG_ERROR, "connect");
452                     return AVERROR(EIO);
453                 }
454             }
455         }
456     }
457 
458     return 0;
459 }
460 
461 /**
462  * Return the local port used by the UDP connection
463  * @param h media file context
464  * @return the local port number
465  */
ff_udp_get_local_port(URLContext * h)466 int ff_udp_get_local_port(URLContext *h)
467 {
468     UDPContext *s = h->priv_data;
469     return s->local_port;
470 }
471 
472 /**
473  * Return the udp file handle for select() usage to wait for several RTP
474  * streams at the same time.
475  * @param h media file context
476  */
udp_get_file_handle(URLContext * h)477 static int udp_get_file_handle(URLContext *h)
478 {
479     UDPContext *s = h->priv_data;
480     return s->udp_fd;
481 }
482 
483 #if HAVE_PTHREAD_CANCEL
circular_buffer_task_rx(void * _URLContext)484 static void *circular_buffer_task_rx( void *_URLContext)
485 {
486     URLContext *h = _URLContext;
487     UDPContext *s = h->priv_data;
488     int old_cancelstate;
489 
490     pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &old_cancelstate);
491     pthread_mutex_lock(&s->mutex);
492     if (ff_socket_nonblock(s->udp_fd, 0) < 0) {
493         av_log(h, AV_LOG_ERROR, "Failed to set blocking mode");
494         s->circular_buffer_error = AVERROR(EIO);
495         goto end;
496     }
497     while(1) {
498         int len;
499         struct sockaddr_storage addr;
500         socklen_t addr_len = sizeof(addr);
501 
502         pthread_mutex_unlock(&s->mutex);
503         /* Blocking operations are always cancellation points;
504            see "General Information" / "Thread Cancelation Overview"
505            in Single Unix. */
506         pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, &old_cancelstate);
507         len = recvfrom(s->udp_fd, s->tmp+4, sizeof(s->tmp)-4, 0, (struct sockaddr *)&addr, &addr_len);
508         pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &old_cancelstate);
509         pthread_mutex_lock(&s->mutex);
510         if (len < 0) {
511             if (ff_neterrno() != AVERROR(EAGAIN) && ff_neterrno() != AVERROR(EINTR)) {
512                 s->circular_buffer_error = ff_neterrno();
513                 goto end;
514             }
515             continue;
516         }
517         if (ff_ip_check_source_lists(&addr, &s->filters))
518             continue;
519         AV_WL32(s->tmp, len);
520 
521         if (av_fifo_can_write(s->fifo) < len + 4) {
522             /* No Space left */
523             if (s->overrun_nonfatal) {
524                 av_log(h, AV_LOG_WARNING, "Circular buffer overrun. "
525                         "Surviving due to overrun_nonfatal option\n");
526                 continue;
527             } else {
528                 av_log(h, AV_LOG_ERROR, "Circular buffer overrun. "
529                         "To avoid, increase fifo_size URL option. "
530                         "To survive in such case, use overrun_nonfatal option\n");
531                 s->circular_buffer_error = AVERROR(EIO);
532                 goto end;
533             }
534         }
535         av_fifo_write(s->fifo, s->tmp, len + 4);
536         pthread_cond_signal(&s->cond);
537     }
538 
539 end:
540     pthread_cond_signal(&s->cond);
541     pthread_mutex_unlock(&s->mutex);
542     return NULL;
543 }
544 
circular_buffer_task_tx(void * _URLContext)545 static void *circular_buffer_task_tx( void *_URLContext)
546 {
547     URLContext *h = _URLContext;
548     UDPContext *s = h->priv_data;
549     int64_t target_timestamp = av_gettime_relative();
550     int64_t start_timestamp = av_gettime_relative();
551     int64_t sent_bits = 0;
552     int64_t burst_interval = s->bitrate ? (s->burst_bits * 1000000 / s->bitrate) : 0;
553     int64_t max_delay = s->bitrate ?  ((int64_t)h->max_packet_size * 8 * 1000000 / s->bitrate + 1) : 0;
554 
555     pthread_mutex_lock(&s->mutex);
556 
557     if (ff_socket_nonblock(s->udp_fd, 0) < 0) {
558         av_log(h, AV_LOG_ERROR, "Failed to set blocking mode");
559         s->circular_buffer_error = AVERROR(EIO);
560         goto end;
561     }
562 
563     for(;;) {
564         int len;
565         const uint8_t *p;
566         uint8_t tmp[4];
567         int64_t timestamp;
568 
569         len = av_fifo_can_read(s->fifo);
570 
571         while (len<4) {
572             if (s->close_req)
573                 goto end;
574             pthread_cond_wait(&s->cond, &s->mutex);
575             len = av_fifo_can_read(s->fifo);
576         }
577 
578         av_fifo_read(s->fifo, tmp, 4);
579         len = AV_RL32(tmp);
580 
581         av_assert0(len >= 0);
582         av_assert0(len <= sizeof(s->tmp));
583 
584         av_fifo_read(s->fifo, s->tmp, len);
585 
586         pthread_mutex_unlock(&s->mutex);
587 
588         if (s->bitrate) {
589             timestamp = av_gettime_relative();
590             if (timestamp < target_timestamp) {
591                 int64_t delay = target_timestamp - timestamp;
592                 if (delay > max_delay) {
593                     delay = max_delay;
594                     start_timestamp = timestamp + delay;
595                     sent_bits = 0;
596                 }
597                 av_usleep(delay);
598             } else {
599                 if (timestamp - burst_interval > target_timestamp) {
600                     start_timestamp = timestamp - burst_interval;
601                     sent_bits = 0;
602                 }
603             }
604             sent_bits += len * 8;
605             target_timestamp = start_timestamp + sent_bits * 1000000 / s->bitrate;
606         }
607 
608         p = s->tmp;
609         while (len) {
610             int ret;
611             av_assert0(len > 0);
612             if (!s->is_connected) {
613                 ret = sendto (s->udp_fd, p, len, 0,
614                             (struct sockaddr *) &s->dest_addr,
615                             s->dest_addr_len);
616             } else
617                 ret = send(s->udp_fd, p, len, 0);
618             if (ret >= 0) {
619                 len -= ret;
620                 p   += ret;
621             } else {
622                 ret = ff_neterrno();
623                 if (ret != AVERROR(EAGAIN) && ret != AVERROR(EINTR)) {
624                     pthread_mutex_lock(&s->mutex);
625                     s->circular_buffer_error = ret;
626                     pthread_mutex_unlock(&s->mutex);
627                     return NULL;
628                 }
629             }
630         }
631 
632         pthread_mutex_lock(&s->mutex);
633     }
634 
635 end:
636     pthread_mutex_unlock(&s->mutex);
637     return NULL;
638 }
639 
640 
641 #endif
642 
643 /* put it in UDP context */
644 /* return non zero if error */
udp_open(URLContext * h,const char * uri,int flags)645 static int udp_open(URLContext *h, const char *uri, int flags)
646 {
647     char hostname[1024];
648     int port, udp_fd = -1, tmp, bind_ret = -1, dscp = -1;
649     UDPContext *s = h->priv_data;
650     int is_output;
651     const char *p;
652     char buf[256];
653     struct sockaddr_storage my_addr;
654     socklen_t len;
655     int ret;
656 
657     h->is_streamed = 1;
658 
659     is_output = !(flags & AVIO_FLAG_READ);
660     if (s->buffer_size < 0)
661         s->buffer_size = is_output ? UDP_TX_BUF_SIZE : UDP_RX_BUF_SIZE;
662 
663     if (s->sources) {
664         if ((ret = ff_ip_parse_sources(h, s->sources, &s->filters)) < 0)
665             goto fail;
666     }
667 
668     if (s->block) {
669         if ((ret = ff_ip_parse_blocks(h, s->block, &s->filters)) < 0)
670             goto fail;
671     }
672 
673     p = strchr(uri, '?');
674     if (p) {
675         if (av_find_info_tag(buf, sizeof(buf), "reuse", p)) {
676             char *endptr = NULL;
677             s->reuse_socket = strtol(buf, &endptr, 10);
678             /* assume if no digits were found it is a request to enable it */
679             if (buf == endptr)
680                 s->reuse_socket = 1;
681         }
682         if (av_find_info_tag(buf, sizeof(buf), "overrun_nonfatal", p)) {
683             char *endptr = NULL;
684             s->overrun_nonfatal = strtol(buf, &endptr, 10);
685             /* assume if no digits were found it is a request to enable it */
686             if (buf == endptr)
687                 s->overrun_nonfatal = 1;
688             if (!HAVE_PTHREAD_CANCEL)
689                 av_log(h, AV_LOG_WARNING,
690                        "'overrun_nonfatal' option was set but it is not supported "
691                        "on this build (pthread support is required)\n");
692         }
693         if (av_find_info_tag(buf, sizeof(buf), "ttl", p)) {
694             s->ttl = strtol(buf, NULL, 10);
695             if (s->ttl < 0 || s->ttl > 255) {
696                 av_log(h, AV_LOG_ERROR, "ttl(%d) should be in range [0,255]\n", s->ttl);
697                 ret = AVERROR(EINVAL);
698                 goto fail;
699             }
700         }
701         if (av_find_info_tag(buf, sizeof(buf), "udplite_coverage", p)) {
702             s->udplite_coverage = strtol(buf, NULL, 10);
703         }
704         if (av_find_info_tag(buf, sizeof(buf), "localport", p)) {
705             s->local_port = strtol(buf, NULL, 10);
706         }
707         if (av_find_info_tag(buf, sizeof(buf), "pkt_size", p)) {
708             s->pkt_size = strtol(buf, NULL, 10);
709         }
710         if (av_find_info_tag(buf, sizeof(buf), "buffer_size", p)) {
711             s->buffer_size = strtol(buf, NULL, 10);
712         }
713         if (av_find_info_tag(buf, sizeof(buf), "connect", p)) {
714             s->is_connected = strtol(buf, NULL, 10);
715         }
716         if (av_find_info_tag(buf, sizeof(buf), "dscp", p)) {
717             dscp = strtol(buf, NULL, 10);
718         }
719         if (av_find_info_tag(buf, sizeof(buf), "fifo_size", p)) {
720             s->circular_buffer_size = strtol(buf, NULL, 10);
721             if (!HAVE_PTHREAD_CANCEL)
722                 av_log(h, AV_LOG_WARNING,
723                        "'circular_buffer_size' option was set but it is not supported "
724                        "on this build (pthread support is required)\n");
725         }
726         if (av_find_info_tag(buf, sizeof(buf), "bitrate", p)) {
727             s->bitrate = strtoll(buf, NULL, 10);
728             if (!HAVE_PTHREAD_CANCEL)
729                 av_log(h, AV_LOG_WARNING,
730                        "'bitrate' option was set but it is not supported "
731                        "on this build (pthread support is required)\n");
732         }
733         if (av_find_info_tag(buf, sizeof(buf), "burst_bits", p)) {
734             s->burst_bits = strtoll(buf, NULL, 10);
735         }
736         if (av_find_info_tag(buf, sizeof(buf), "localaddr", p)) {
737             av_freep(&s->localaddr);
738             s->localaddr = av_strdup(buf);
739         }
740         if (av_find_info_tag(buf, sizeof(buf), "sources", p)) {
741             if ((ret = ff_ip_parse_sources(h, buf, &s->filters)) < 0)
742                 goto fail;
743         }
744         if (av_find_info_tag(buf, sizeof(buf), "block", p)) {
745             if ((ret = ff_ip_parse_blocks(h, buf, &s->filters)) < 0)
746                 goto fail;
747         }
748         if (!is_output && av_find_info_tag(buf, sizeof(buf), "timeout", p))
749             s->timeout = strtol(buf, NULL, 10);
750         if (is_output && av_find_info_tag(buf, sizeof(buf), "broadcast", p))
751             s->is_broadcast = strtol(buf, NULL, 10);
752     }
753     /* handling needed to support options picking from both AVOption and URL */
754     s->circular_buffer_size *= 188;
755     if (flags & AVIO_FLAG_WRITE) {
756         h->max_packet_size = s->pkt_size;
757     } else {
758         h->max_packet_size = UDP_MAX_PKT_SIZE;
759     }
760     h->rw_timeout = s->timeout;
761 
762     /* fill the dest addr */
763     av_url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &port, NULL, 0, uri);
764 
765     /* XXX: fix av_url_split */
766     if (hostname[0] == '\0' || hostname[0] == '?') {
767         /* only accepts null hostname if input */
768         if (!(flags & AVIO_FLAG_READ)) {
769             ret = AVERROR(EINVAL);
770             goto fail;
771         }
772     } else {
773         if ((ret = ff_udp_set_remote_url(h, uri)) < 0)
774             goto fail;
775     }
776 
777     if ((s->is_multicast || s->local_port <= 0) && (h->flags & AVIO_FLAG_READ))
778         s->local_port = port;
779 
780     udp_fd = udp_socket_create(h, &my_addr, &len, s->localaddr);
781     if (udp_fd < 0) {
782         ret = AVERROR(EIO);
783         goto fail;
784     }
785 
786     s->local_addr_storage=my_addr; //store for future multicast join
787 
788     /* Follow the requested reuse option, unless it's multicast in which
789      * case enable reuse unless explicitly disabled.
790      */
791     if (s->reuse_socket > 0 || (s->is_multicast && s->reuse_socket < 0)) {
792         s->reuse_socket = 1;
793         if (setsockopt (udp_fd, SOL_SOCKET, SO_REUSEADDR, &(s->reuse_socket), sizeof(s->reuse_socket)) != 0) {
794             ret = ff_neterrno();
795             goto fail;
796         }
797     }
798 
799     if (s->is_broadcast) {
800 #ifdef SO_BROADCAST
801         if (setsockopt (udp_fd, SOL_SOCKET, SO_BROADCAST, &(s->is_broadcast), sizeof(s->is_broadcast)) != 0) {
802             ret = ff_neterrno();
803             goto fail;
804         }
805 #else
806         ret = AVERROR(ENOSYS);
807         goto fail;
808 #endif
809     }
810 
811     /* Set the checksum coverage for UDP-Lite (RFC 3828) for sending and receiving.
812      * The receiver coverage has to be less than or equal to the sender coverage.
813      * Otherwise, the receiver will drop all packets.
814      */
815     if (s->udplite_coverage) {
816         if (setsockopt (udp_fd, IPPROTO_UDPLITE, UDPLITE_SEND_CSCOV, &(s->udplite_coverage), sizeof(s->udplite_coverage)) != 0)
817             av_log(h, AV_LOG_WARNING, "socket option UDPLITE_SEND_CSCOV not available");
818 
819         if (setsockopt (udp_fd, IPPROTO_UDPLITE, UDPLITE_RECV_CSCOV, &(s->udplite_coverage), sizeof(s->udplite_coverage)) != 0)
820             av_log(h, AV_LOG_WARNING, "socket option UDPLITE_RECV_CSCOV not available");
821     }
822 
823     if (dscp >= 0) {
824         dscp <<= 2;
825         if (setsockopt (udp_fd, IPPROTO_IP, IP_TOS, &dscp, sizeof(dscp)) != 0) {
826             ret = ff_neterrno();
827             goto fail;
828         }
829     }
830 
831     /* If multicast, try binding the multicast address first, to avoid
832      * receiving UDP packets from other sources aimed at the same UDP
833      * port. This fails on windows. This makes sending to the same address
834      * using sendto() fail, so only do it if we're opened in read-only mode. */
835     if (s->is_multicast && (h->flags & AVIO_FLAG_READ)) {
836         bind_ret = bind(udp_fd,(struct sockaddr *)&s->dest_addr, len);
837     }
838     /* bind to the local address if not multicast or if the multicast
839      * bind failed */
840     /* the bind is needed to give a port to the socket now */
841     if (bind_ret < 0 && bind(udp_fd,(struct sockaddr *)&my_addr, len) < 0) {
842         ff_log_net_error(h, AV_LOG_ERROR, "bind failed");
843         ret = ff_neterrno();
844         goto fail;
845     }
846 
847     len = sizeof(my_addr);
848     getsockname(udp_fd, (struct sockaddr *)&my_addr, &len);
849     s->local_port = udp_port(&my_addr, len);
850 
851     if (s->is_multicast) {
852         if (h->flags & AVIO_FLAG_WRITE) {
853             /* output */
854             if ((ret = udp_set_multicast_ttl(udp_fd, s->ttl, (struct sockaddr *)&s->dest_addr, h)) < 0)
855                 goto fail;
856         }
857         if (h->flags & AVIO_FLAG_READ) {
858             /* input */
859             if (s->filters.nb_include_addrs) {
860                 if ((ret = udp_set_multicast_sources(h, udp_fd,
861                                               (struct sockaddr *)&s->dest_addr,
862                                               s->dest_addr_len, &s->local_addr_storage,
863                                               s->filters.include_addrs,
864                                               s->filters.nb_include_addrs, 1)) < 0)
865                     goto fail;
866             } else {
867                 if ((ret = udp_join_multicast_group(udp_fd, (struct sockaddr *)&s->dest_addr,
868                                                     (struct sockaddr *)&s->local_addr_storage, h)) < 0)
869                     goto fail;
870             }
871             if (s->filters.nb_exclude_addrs) {
872                 if ((ret = udp_set_multicast_sources(h, udp_fd,
873                                               (struct sockaddr *)&s->dest_addr,
874                                               s->dest_addr_len, &s->local_addr_storage,
875                                               s->filters.exclude_addrs,
876                                               s->filters.nb_exclude_addrs, 0)) < 0)
877                     goto fail;
878             }
879         }
880     }
881 
882     if (is_output) {
883         /* limit the tx buf size to limit latency */
884         tmp = s->buffer_size;
885         if (setsockopt(udp_fd, SOL_SOCKET, SO_SNDBUF, &tmp, sizeof(tmp)) < 0) {
886             ff_log_net_error(h, AV_LOG_ERROR, "setsockopt(SO_SNDBUF)");
887             ret = ff_neterrno();
888             goto fail;
889         }
890     } else {
891         /* set udp recv buffer size to the requested value (default UDP_RX_BUF_SIZE) */
892         tmp = s->buffer_size;
893         if (setsockopt(udp_fd, SOL_SOCKET, SO_RCVBUF, &tmp, sizeof(tmp)) < 0) {
894             ff_log_net_error(h, AV_LOG_WARNING, "setsockopt(SO_RECVBUF)");
895         }
896         len = sizeof(tmp);
897         if (getsockopt(udp_fd, SOL_SOCKET, SO_RCVBUF, &tmp, &len) < 0) {
898             ff_log_net_error(h, AV_LOG_WARNING, "getsockopt(SO_RCVBUF)");
899         } else {
900             av_log(h, AV_LOG_DEBUG, "end receive buffer size reported is %d\n", tmp);
901             if(tmp < s->buffer_size)
902                 av_log(h, AV_LOG_WARNING, "attempted to set receive buffer to size %d but it only ended up set as %d\n", s->buffer_size, tmp);
903         }
904 
905         /* make the socket non-blocking */
906         ff_socket_nonblock(udp_fd, 1);
907     }
908     if (s->is_connected) {
909         if (connect(udp_fd, (struct sockaddr *) &s->dest_addr, s->dest_addr_len)) {
910             ff_log_net_error(h, AV_LOG_ERROR, "connect");
911             ret = ff_neterrno();
912             goto fail;
913         }
914     }
915 
916     s->udp_fd = udp_fd;
917 
918 #if HAVE_PTHREAD_CANCEL
919     /*
920       Create thread in case of:
921       1. Input and circular_buffer_size is set
922       2. Output and bitrate and circular_buffer_size is set
923     */
924 
925     if (is_output && s->bitrate && !s->circular_buffer_size) {
926         /* Warn user in case of 'circular_buffer_size' is not set */
927         av_log(h, AV_LOG_WARNING,"'bitrate' option was set but 'circular_buffer_size' is not, but required\n");
928     }
929 
930     if ((!is_output && s->circular_buffer_size) || (is_output && s->bitrate && s->circular_buffer_size)) {
931         /* start the task going */
932         s->fifo = av_fifo_alloc2(s->circular_buffer_size, 1, 0);
933         if (!s->fifo) {
934             ret = AVERROR(ENOMEM);
935             goto fail;
936         }
937         ret = pthread_mutex_init(&s->mutex, NULL);
938         if (ret != 0) {
939             av_log(h, AV_LOG_ERROR, "pthread_mutex_init failed : %s\n", strerror(ret));
940             ret = AVERROR(ret);
941             goto fail;
942         }
943         ret = pthread_cond_init(&s->cond, NULL);
944         if (ret != 0) {
945             av_log(h, AV_LOG_ERROR, "pthread_cond_init failed : %s\n", strerror(ret));
946             ret = AVERROR(ret);
947             goto cond_fail;
948         }
949         ret = pthread_create(&s->circular_buffer_thread, NULL, is_output?circular_buffer_task_tx:circular_buffer_task_rx, h);
950         if (ret != 0) {
951             av_log(h, AV_LOG_ERROR, "pthread_create failed : %s\n", strerror(ret));
952             ret = AVERROR(ret);
953             goto thread_fail;
954         }
955         s->thread_started = 1;
956     }
957 #endif
958 
959     return 0;
960 #if HAVE_PTHREAD_CANCEL
961  thread_fail:
962     pthread_cond_destroy(&s->cond);
963  cond_fail:
964     pthread_mutex_destroy(&s->mutex);
965 #endif
966  fail:
967     if (udp_fd >= 0)
968         closesocket(udp_fd);
969     av_fifo_freep2(&s->fifo);
970     ff_ip_reset_filters(&s->filters);
971     return ret;
972 }
973 
udplite_open(URLContext * h,const char * uri,int flags)974 static int udplite_open(URLContext *h, const char *uri, int flags)
975 {
976     UDPContext *s = h->priv_data;
977 
978     // set default checksum coverage
979     s->udplite_coverage = UDP_HEADER_SIZE;
980 
981     return udp_open(h, uri, flags);
982 }
983 
udp_read(URLContext * h,uint8_t * buf,int size)984 static int udp_read(URLContext *h, uint8_t *buf, int size)
985 {
986     UDPContext *s = h->priv_data;
987     int ret;
988     struct sockaddr_storage addr;
989     socklen_t addr_len = sizeof(addr);
990 #if HAVE_PTHREAD_CANCEL
991     int avail, nonblock = h->flags & AVIO_FLAG_NONBLOCK;
992 
993     if (s->fifo) {
994         pthread_mutex_lock(&s->mutex);
995         do {
996             avail = av_fifo_can_read(s->fifo);
997             if (avail) { // >=size) {
998                 uint8_t tmp[4];
999 
1000                 av_fifo_read(s->fifo, tmp, 4);
1001                 avail = AV_RL32(tmp);
1002                 if(avail > size){
1003                     av_log(h, AV_LOG_WARNING, "Part of datagram lost due to insufficient buffer size\n");
1004                     avail = size;
1005                 }
1006 
1007                 av_fifo_read(s->fifo, buf, avail);
1008                 av_fifo_drain2(s->fifo, AV_RL32(tmp) - avail);
1009                 pthread_mutex_unlock(&s->mutex);
1010                 return avail;
1011             } else if(s->circular_buffer_error){
1012                 int err = s->circular_buffer_error;
1013                 pthread_mutex_unlock(&s->mutex);
1014                 return err;
1015             } else if(nonblock) {
1016                 pthread_mutex_unlock(&s->mutex);
1017                 return AVERROR(EAGAIN);
1018             } else {
1019                 /* FIXME: using the monotonic clock would be better,
1020                    but it does not exist on all supported platforms. */
1021                 int64_t t = av_gettime() + 100000;
1022                 struct timespec tv = { .tv_sec  =  t / 1000000,
1023                                        .tv_nsec = (t % 1000000) * 1000 };
1024                 int err = pthread_cond_timedwait(&s->cond, &s->mutex, &tv);
1025                 if (err) {
1026                     pthread_mutex_unlock(&s->mutex);
1027                     return AVERROR(err == ETIMEDOUT ? EAGAIN : err);
1028                 }
1029                 nonblock = 1;
1030             }
1031         } while(1);
1032     }
1033 #endif
1034 
1035     if (!(h->flags & AVIO_FLAG_NONBLOCK)) {
1036         ret = ff_network_wait_fd(s->udp_fd, 0);
1037         if (ret < 0)
1038             return ret;
1039     }
1040     ret = recvfrom(s->udp_fd, buf, size, 0, (struct sockaddr *)&addr, &addr_len);
1041     if (ret < 0)
1042         return ff_neterrno();
1043     if (ff_ip_check_source_lists(&addr, &s->filters))
1044         return AVERROR(EINTR);
1045     return ret;
1046 }
1047 
udp_write(URLContext * h,const uint8_t * buf,int size)1048 static int udp_write(URLContext *h, const uint8_t *buf, int size)
1049 {
1050     UDPContext *s = h->priv_data;
1051     int ret;
1052 
1053 #if HAVE_PTHREAD_CANCEL
1054     if (s->fifo) {
1055         uint8_t tmp[4];
1056 
1057         pthread_mutex_lock(&s->mutex);
1058 
1059         /*
1060           Return error if last tx failed.
1061           Here we can't know on which packet error was, but it needs to know that error exists.
1062         */
1063         if (s->circular_buffer_error<0) {
1064             int err = s->circular_buffer_error;
1065             pthread_mutex_unlock(&s->mutex);
1066             return err;
1067         }
1068 
1069         if (av_fifo_can_write(s->fifo) < size + 4) {
1070             /* What about a partial packet tx ? */
1071             pthread_mutex_unlock(&s->mutex);
1072             return AVERROR(ENOMEM);
1073         }
1074         AV_WL32(tmp, size);
1075         av_fifo_write(s->fifo, tmp, 4); /* size of packet */
1076         av_fifo_write(s->fifo, buf, size); /* the data */
1077         pthread_cond_signal(&s->cond);
1078         pthread_mutex_unlock(&s->mutex);
1079         return size;
1080     }
1081 #endif
1082     if (!(h->flags & AVIO_FLAG_NONBLOCK)) {
1083         ret = ff_network_wait_fd(s->udp_fd, 1);
1084         if (ret < 0)
1085             return ret;
1086     }
1087 
1088     if (!s->is_connected) {
1089         ret = sendto (s->udp_fd, buf, size, 0,
1090                       (struct sockaddr *) &s->dest_addr,
1091                       s->dest_addr_len);
1092     } else
1093         ret = send(s->udp_fd, buf, size, 0);
1094 
1095     return ret < 0 ? ff_neterrno() : ret;
1096 }
1097 
udp_close(URLContext * h)1098 static int udp_close(URLContext *h)
1099 {
1100     UDPContext *s = h->priv_data;
1101 
1102 #if HAVE_PTHREAD_CANCEL
1103     // Request close once writing is finished
1104     if (s->thread_started && !(h->flags & AVIO_FLAG_READ)) {
1105         pthread_mutex_lock(&s->mutex);
1106         s->close_req = 1;
1107         pthread_cond_signal(&s->cond);
1108         pthread_mutex_unlock(&s->mutex);
1109     }
1110 #endif
1111 
1112     if (s->is_multicast && (h->flags & AVIO_FLAG_READ))
1113         udp_leave_multicast_group(s->udp_fd, (struct sockaddr *)&s->dest_addr,
1114                                   (struct sockaddr *)&s->local_addr_storage, h);
1115 #if HAVE_PTHREAD_CANCEL
1116     if (s->thread_started) {
1117         int ret;
1118         // Cancel only read, as write has been signaled as success to the user
1119         if (h->flags & AVIO_FLAG_READ) {
1120 #ifdef _WIN32
1121             /* recvfrom() is not a cancellation point for win32, so we shutdown
1122              * the socket and abort pending IO, subsequent recvfrom() calls
1123              * will fail with WSAESHUTDOWN causing the thread to exit. */
1124             shutdown(s->udp_fd, SD_RECEIVE);
1125             CancelIoEx((HANDLE)(SOCKET)s->udp_fd, NULL);
1126 #else
1127             pthread_cancel(s->circular_buffer_thread);
1128 #endif
1129         }
1130         ret = pthread_join(s->circular_buffer_thread, NULL);
1131         if (ret != 0)
1132             av_log(h, AV_LOG_ERROR, "pthread_join(): %s\n", strerror(ret));
1133         pthread_mutex_destroy(&s->mutex);
1134         pthread_cond_destroy(&s->cond);
1135     }
1136 #endif
1137     closesocket(s->udp_fd);
1138     av_fifo_freep2(&s->fifo);
1139     ff_ip_reset_filters(&s->filters);
1140     return 0;
1141 }
1142 
1143 const URLProtocol ff_udp_protocol = {
1144     .name                = "udp",
1145     .url_open            = udp_open,
1146     .url_read            = udp_read,
1147     .url_write           = udp_write,
1148     .url_close           = udp_close,
1149     .url_get_file_handle = udp_get_file_handle,
1150     .priv_data_size      = sizeof(UDPContext),
1151     .priv_data_class     = &udp_class,
1152     .flags               = URL_PROTOCOL_FLAG_NETWORK,
1153 };
1154 
1155 const URLProtocol ff_udplite_protocol = {
1156     .name                = "udplite",
1157     .url_open            = udplite_open,
1158     .url_read            = udp_read,
1159     .url_write           = udp_write,
1160     .url_close           = udp_close,
1161     .url_get_file_handle = udp_get_file_handle,
1162     .priv_data_size      = sizeof(UDPContext),
1163     .priv_data_class     = &udplite_context_class,
1164     .flags               = URL_PROTOCOL_FLAG_NETWORK,
1165 };
1166