libavformat/udp.c
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00001 /*
00002  * UDP prototype streaming system
00003  * Copyright (c) 2000, 2001, 2002 Fabrice Bellard
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * FFmpeg is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with FFmpeg; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00027 #define _BSD_SOURCE     /* Needed for using struct ip_mreq with recent glibc */
00028 
00029 #include "avformat.h"
00030 #include "avio_internal.h"
00031 #include "libavutil/parseutils.h"
00032 #include "libavutil/fifo.h"
00033 #include "libavutil/intreadwrite.h"
00034 #include "libavutil/avstring.h"
00035 #include <unistd.h>
00036 #include "internal.h"
00037 #include "network.h"
00038 #include "os_support.h"
00039 #include "url.h"
00040 
00041 #if HAVE_PTHREADS
00042 #include <pthread.h>
00043 #endif
00044 
00045 #include <sys/time.h>
00046 
00047 #ifndef IPV6_ADD_MEMBERSHIP
00048 #define IPV6_ADD_MEMBERSHIP IPV6_JOIN_GROUP
00049 #define IPV6_DROP_MEMBERSHIP IPV6_LEAVE_GROUP
00050 #endif
00051 
00052 #define UDP_TX_BUF_SIZE 32768
00053 #define UDP_MAX_PKT_SIZE 65536
00054 
00055 typedef struct {
00056     int udp_fd;
00057     int ttl;
00058     int buffer_size;
00059     int is_multicast;
00060     int local_port;
00061     int reuse_socket;
00062     struct sockaddr_storage dest_addr;
00063     int dest_addr_len;
00064     int is_connected;
00065 
00066     /* Circular Buffer variables for use in UDP receive code */
00067     int circular_buffer_size;
00068     AVFifoBuffer *fifo;
00069     int circular_buffer_error;
00070 #if HAVE_PTHREADS
00071     pthread_t circular_buffer_thread;
00072     pthread_mutex_t mutex;
00073     pthread_cond_t cond;
00074     int thread_started;
00075     volatile int exit_thread;
00076 #endif
00077     uint8_t tmp[UDP_MAX_PKT_SIZE+4];
00078     int remaining_in_dg;
00079 } UDPContext;
00080 
00081 static int udp_set_multicast_ttl(int sockfd, int mcastTTL,
00082                                  struct sockaddr *addr)
00083 {
00084 #ifdef IP_MULTICAST_TTL
00085     if (addr->sa_family == AF_INET) {
00086         if (setsockopt(sockfd, IPPROTO_IP, IP_MULTICAST_TTL, &mcastTTL, sizeof(mcastTTL)) < 0) {
00087             av_log(NULL, AV_LOG_ERROR, "setsockopt(IP_MULTICAST_TTL): %s\n", strerror(errno));
00088             return -1;
00089         }
00090     }
00091 #endif
00092 #if defined(IPPROTO_IPV6) && defined(IPV6_MULTICAST_HOPS)
00093     if (addr->sa_family == AF_INET6) {
00094         if (setsockopt(sockfd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &mcastTTL, sizeof(mcastTTL)) < 0) {
00095             av_log(NULL, AV_LOG_ERROR, "setsockopt(IPV6_MULTICAST_HOPS): %s\n", strerror(errno));
00096             return -1;
00097         }
00098     }
00099 #endif
00100     return 0;
00101 }
00102 
00103 static int udp_join_multicast_group(int sockfd, struct sockaddr *addr)
00104 {
00105 #ifdef IP_ADD_MEMBERSHIP
00106     if (addr->sa_family == AF_INET) {
00107         struct ip_mreq mreq;
00108 
00109         mreq.imr_multiaddr.s_addr = ((struct sockaddr_in *)addr)->sin_addr.s_addr;
00110         mreq.imr_interface.s_addr= INADDR_ANY;
00111         if (setsockopt(sockfd, IPPROTO_IP, IP_ADD_MEMBERSHIP, (const void *)&mreq, sizeof(mreq)) < 0) {
00112             av_log(NULL, AV_LOG_ERROR, "setsockopt(IP_ADD_MEMBERSHIP): %s\n", strerror(errno));
00113             return -1;
00114         }
00115     }
00116 #endif
00117 #if HAVE_STRUCT_IPV6_MREQ && defined(IPPROTO_IPV6)
00118     if (addr->sa_family == AF_INET6) {
00119         struct ipv6_mreq mreq6;
00120 
00121         memcpy(&mreq6.ipv6mr_multiaddr, &(((struct sockaddr_in6 *)addr)->sin6_addr), sizeof(struct in6_addr));
00122         mreq6.ipv6mr_interface= 0;
00123         if (setsockopt(sockfd, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &mreq6, sizeof(mreq6)) < 0) {
00124             av_log(NULL, AV_LOG_ERROR, "setsockopt(IPV6_ADD_MEMBERSHIP): %s\n", strerror(errno));
00125             return -1;
00126         }
00127     }
00128 #endif
00129     return 0;
00130 }
00131 
00132 static int udp_leave_multicast_group(int sockfd, struct sockaddr *addr)
00133 {
00134 #ifdef IP_DROP_MEMBERSHIP
00135     if (addr->sa_family == AF_INET) {
00136         struct ip_mreq mreq;
00137 
00138         mreq.imr_multiaddr.s_addr = ((struct sockaddr_in *)addr)->sin_addr.s_addr;
00139         mreq.imr_interface.s_addr= INADDR_ANY;
00140         if (setsockopt(sockfd, IPPROTO_IP, IP_DROP_MEMBERSHIP, (const void *)&mreq, sizeof(mreq)) < 0) {
00141             av_log(NULL, AV_LOG_ERROR, "setsockopt(IP_DROP_MEMBERSHIP): %s\n", strerror(errno));
00142             return -1;
00143         }
00144     }
00145 #endif
00146 #if HAVE_STRUCT_IPV6_MREQ && defined(IPPROTO_IPV6)
00147     if (addr->sa_family == AF_INET6) {
00148         struct ipv6_mreq mreq6;
00149 
00150         memcpy(&mreq6.ipv6mr_multiaddr, &(((struct sockaddr_in6 *)addr)->sin6_addr), sizeof(struct in6_addr));
00151         mreq6.ipv6mr_interface= 0;
00152         if (setsockopt(sockfd, IPPROTO_IPV6, IPV6_DROP_MEMBERSHIP, &mreq6, sizeof(mreq6)) < 0) {
00153             av_log(NULL, AV_LOG_ERROR, "setsockopt(IPV6_DROP_MEMBERSHIP): %s\n", strerror(errno));
00154             return -1;
00155         }
00156     }
00157 #endif
00158     return 0;
00159 }
00160 
00161 static struct addrinfo* udp_resolve_host(const char *hostname, int port,
00162                                          int type, int family, int flags)
00163 {
00164     struct addrinfo hints, *res = 0;
00165     int error;
00166     char sport[16];
00167     const char *node = 0, *service = "0";
00168 
00169     if (port > 0) {
00170         snprintf(sport, sizeof(sport), "%d", port);
00171         service = sport;
00172     }
00173     if ((hostname) && (hostname[0] != '\0') && (hostname[0] != '?')) {
00174         node = hostname;
00175     }
00176     memset(&hints, 0, sizeof(hints));
00177     hints.ai_socktype = type;
00178     hints.ai_family   = family;
00179     hints.ai_flags = flags;
00180     if ((error = getaddrinfo(node, service, &hints, &res))) {
00181         res = NULL;
00182         av_log(NULL, AV_LOG_ERROR, "udp_resolve_host: %s\n", gai_strerror(error));
00183     }
00184 
00185     return res;
00186 }
00187 
00188 static int udp_set_url(struct sockaddr_storage *addr,
00189                        const char *hostname, int port)
00190 {
00191     struct addrinfo *res0;
00192     int addr_len;
00193 
00194     res0 = udp_resolve_host(hostname, port, SOCK_DGRAM, AF_UNSPEC, 0);
00195     if (res0 == 0) return AVERROR(EIO);
00196     memcpy(addr, res0->ai_addr, res0->ai_addrlen);
00197     addr_len = res0->ai_addrlen;
00198     freeaddrinfo(res0);
00199 
00200     return addr_len;
00201 }
00202 
00203 static int udp_socket_create(UDPContext *s, struct sockaddr_storage *addr,
00204                              int *addr_len, const char *localaddr)
00205 {
00206     int udp_fd = -1;
00207     struct addrinfo *res0 = NULL, *res = NULL;
00208     int family = AF_UNSPEC;
00209 
00210     if (((struct sockaddr *) &s->dest_addr)->sa_family)
00211         family = ((struct sockaddr *) &s->dest_addr)->sa_family;
00212     res0 = udp_resolve_host(localaddr[0] ? localaddr : NULL, s->local_port,
00213                             SOCK_DGRAM, family, AI_PASSIVE);
00214     if (res0 == 0)
00215         goto fail;
00216     for (res = res0; res; res=res->ai_next) {
00217         udp_fd = socket(res->ai_family, SOCK_DGRAM, 0);
00218         if (udp_fd > 0) break;
00219         av_log(NULL, AV_LOG_ERROR, "socket: %s\n", strerror(errno));
00220     }
00221 
00222     if (udp_fd < 0)
00223         goto fail;
00224 
00225     memcpy(addr, res->ai_addr, res->ai_addrlen);
00226     *addr_len = res->ai_addrlen;
00227 
00228     freeaddrinfo(res0);
00229 
00230     return udp_fd;
00231 
00232  fail:
00233     if (udp_fd >= 0)
00234         closesocket(udp_fd);
00235     if(res0)
00236         freeaddrinfo(res0);
00237     return -1;
00238 }
00239 
00240 static int udp_port(struct sockaddr_storage *addr, int addr_len)
00241 {
00242     char sbuf[sizeof(int)*3+1];
00243 
00244     if (getnameinfo((struct sockaddr *)addr, addr_len, NULL, 0,  sbuf, sizeof(sbuf), NI_NUMERICSERV) != 0) {
00245         av_log(NULL, AV_LOG_ERROR, "getnameinfo: %s\n", strerror(errno));
00246         return -1;
00247     }
00248 
00249     return strtol(sbuf, NULL, 10);
00250 }
00251 
00252 
00268 int ff_udp_set_remote_url(URLContext *h, const char *uri)
00269 {
00270     UDPContext *s = h->priv_data;
00271     char hostname[256], buf[10];
00272     int port;
00273     const char *p;
00274 
00275     av_url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &port, NULL, 0, uri);
00276 
00277     /* set the destination address */
00278     s->dest_addr_len = udp_set_url(&s->dest_addr, hostname, port);
00279     if (s->dest_addr_len < 0) {
00280         return AVERROR(EIO);
00281     }
00282     s->is_multicast = ff_is_multicast_address((struct sockaddr*) &s->dest_addr);
00283     p = strchr(uri, '?');
00284     if (p) {
00285         if (av_find_info_tag(buf, sizeof(buf), "connect", p)) {
00286             int was_connected = s->is_connected;
00287             s->is_connected = strtol(buf, NULL, 10);
00288             if (s->is_connected && !was_connected) {
00289                 if (connect(s->udp_fd, (struct sockaddr *) &s->dest_addr,
00290                             s->dest_addr_len)) {
00291                     s->is_connected = 0;
00292                     av_log(h, AV_LOG_ERROR, "connect: %s\n", strerror(errno));
00293                     return AVERROR(EIO);
00294                 }
00295             }
00296         }
00297     }
00298 
00299     return 0;
00300 }
00301 
00307 int ff_udp_get_local_port(URLContext *h)
00308 {
00309     UDPContext *s = h->priv_data;
00310     return s->local_port;
00311 }
00312 
00318 static int udp_get_file_handle(URLContext *h)
00319 {
00320     UDPContext *s = h->priv_data;
00321     return s->udp_fd;
00322 }
00323 
00324 #if HAVE_PTHREADS
00325 static void *circular_buffer_task( void *_URLContext)
00326 {
00327     URLContext *h = _URLContext;
00328     UDPContext *s = h->priv_data;
00329     fd_set rfds;
00330     struct timeval tv;
00331 
00332     while(!s->exit_thread) {
00333         int left;
00334         int ret;
00335         int len;
00336 
00337         if (ff_check_interrupt(&h->interrupt_callback)) {
00338             s->circular_buffer_error = EINTR;
00339             goto end;
00340         }
00341 
00342         FD_ZERO(&rfds);
00343         FD_SET(s->udp_fd, &rfds);
00344         tv.tv_sec = 1;
00345         tv.tv_usec = 0;
00346         ret = select(s->udp_fd + 1, &rfds, NULL, NULL, &tv);
00347         if (ret < 0) {
00348             if (ff_neterrno() == AVERROR(EINTR))
00349                 continue;
00350             s->circular_buffer_error = EIO;
00351             goto end;
00352         }
00353 
00354         if (!(ret > 0 && FD_ISSET(s->udp_fd, &rfds)))
00355             continue;
00356 
00357         /* How much do we have left to the end of the buffer */
00358         /* Whats the minimum we can read so that we dont comletely fill the buffer */
00359         left = av_fifo_space(s->fifo);
00360 
00361         /* No Space left, error, what do we do now */
00362         if(left < UDP_MAX_PKT_SIZE + 4) {
00363             av_log(h, AV_LOG_ERROR, "circular_buffer: OVERRUN\n");
00364             s->circular_buffer_error = EIO;
00365             goto end;
00366         }
00367         left = FFMIN(left, s->fifo->end - s->fifo->wptr);
00368         len = recv(s->udp_fd, s->tmp+4, sizeof(s->tmp)-4, 0);
00369         if (len < 0) {
00370             if (ff_neterrno() != AVERROR(EAGAIN) && ff_neterrno() != AVERROR(EINTR)) {
00371                 s->circular_buffer_error = EIO;
00372                 goto end;
00373             }
00374             continue;
00375         }
00376         AV_WL32(s->tmp, len);
00377         pthread_mutex_lock(&s->mutex);
00378         av_fifo_generic_write(s->fifo, s->tmp, len+4, NULL);
00379         pthread_cond_signal(&s->cond);
00380         pthread_mutex_unlock(&s->mutex);
00381     }
00382 
00383 end:
00384     pthread_mutex_lock(&s->mutex);
00385     pthread_cond_signal(&s->cond);
00386     pthread_mutex_unlock(&s->mutex);
00387     return NULL;
00388 }
00389 #endif
00390 
00391 /* put it in UDP context */
00392 /* return non zero if error */
00393 static int udp_open(URLContext *h, const char *uri, int flags)
00394 {
00395     char hostname[1024], localaddr[1024] = "";
00396     int port, udp_fd = -1, tmp, bind_ret = -1;
00397     UDPContext *s = h->priv_data;
00398     int is_output;
00399     const char *p;
00400     char buf[256];
00401     struct sockaddr_storage my_addr;
00402     int len;
00403     int reuse_specified = 0;
00404 
00405     h->is_streamed = 1;
00406     h->max_packet_size = 1472;
00407 
00408     is_output = !(flags & AVIO_FLAG_READ);
00409 
00410     s->ttl = 16;
00411     s->buffer_size = is_output ? UDP_TX_BUF_SIZE : UDP_MAX_PKT_SIZE;
00412 
00413     s->circular_buffer_size = 7*188*4096;
00414 
00415     p = strchr(uri, '?');
00416     if (p) {
00417         if (av_find_info_tag(buf, sizeof(buf), "reuse", p)) {
00418             char *endptr = NULL;
00419             s->reuse_socket = strtol(buf, &endptr, 10);
00420             /* assume if no digits were found it is a request to enable it */
00421             if (buf == endptr)
00422                 s->reuse_socket = 1;
00423             reuse_specified = 1;
00424         }
00425         if (av_find_info_tag(buf, sizeof(buf), "ttl", p)) {
00426             s->ttl = strtol(buf, NULL, 10);
00427         }
00428         if (av_find_info_tag(buf, sizeof(buf), "localport", p)) {
00429             s->local_port = strtol(buf, NULL, 10);
00430         }
00431         if (av_find_info_tag(buf, sizeof(buf), "pkt_size", p)) {
00432             h->max_packet_size = strtol(buf, NULL, 10);
00433         }
00434         if (av_find_info_tag(buf, sizeof(buf), "buffer_size", p)) {
00435             s->buffer_size = strtol(buf, NULL, 10);
00436         }
00437         if (av_find_info_tag(buf, sizeof(buf), "connect", p)) {
00438             s->is_connected = strtol(buf, NULL, 10);
00439         }
00440         if (av_find_info_tag(buf, sizeof(buf), "fifo_size", p)) {
00441             s->circular_buffer_size = strtol(buf, NULL, 10)*188;
00442         }
00443         if (av_find_info_tag(buf, sizeof(buf), "localaddr", p)) {
00444             av_strlcpy(localaddr, buf, sizeof(localaddr));
00445         }
00446     }
00447 
00448     /* fill the dest addr */
00449     av_url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &port, NULL, 0, uri);
00450 
00451     /* XXX: fix av_url_split */
00452     if (hostname[0] == '\0' || hostname[0] == '?') {
00453         /* only accepts null hostname if input */
00454         if (!(flags & AVIO_FLAG_READ))
00455             goto fail;
00456     } else {
00457         if (ff_udp_set_remote_url(h, uri) < 0)
00458             goto fail;
00459     }
00460 
00461     if ((s->is_multicast || !s->local_port) && (h->flags & AVIO_FLAG_READ))
00462         s->local_port = port;
00463     udp_fd = udp_socket_create(s, &my_addr, &len, localaddr);
00464     if (udp_fd < 0)
00465         goto fail;
00466 
00467     /* Follow the requested reuse option, unless it's multicast in which
00468      * case enable reuse unless explicitly disabled.
00469      */
00470     if (s->reuse_socket || (s->is_multicast && !reuse_specified)) {
00471         s->reuse_socket = 1;
00472         if (setsockopt (udp_fd, SOL_SOCKET, SO_REUSEADDR, &(s->reuse_socket), sizeof(s->reuse_socket)) != 0)
00473             goto fail;
00474     }
00475 
00476     /* the bind is needed to give a port to the socket now */
00477     /* if multicast, try the multicast address bind first */
00478     if (s->is_multicast && (h->flags & AVIO_FLAG_READ)) {
00479         bind_ret = bind(udp_fd,(struct sockaddr *)&s->dest_addr, len);
00480     }
00481     /* bind to the local address if not multicast or if the multicast
00482      * bind failed */
00483     if (bind_ret < 0 && bind(udp_fd,(struct sockaddr *)&my_addr, len) < 0)
00484         goto fail;
00485 
00486     len = sizeof(my_addr);
00487     getsockname(udp_fd, (struct sockaddr *)&my_addr, &len);
00488     s->local_port = udp_port(&my_addr, len);
00489 
00490     if (s->is_multicast) {
00491         if (!(h->flags & AVIO_FLAG_READ)) {
00492             /* output */
00493             if (udp_set_multicast_ttl(udp_fd, s->ttl, (struct sockaddr *)&s->dest_addr) < 0)
00494                 goto fail;
00495         } else {
00496             /* input */
00497             if (udp_join_multicast_group(udp_fd, (struct sockaddr *)&s->dest_addr) < 0)
00498                 goto fail;
00499         }
00500     }
00501 
00502     if (is_output) {
00503         /* limit the tx buf size to limit latency */
00504         tmp = s->buffer_size;
00505         if (setsockopt(udp_fd, SOL_SOCKET, SO_SNDBUF, &tmp, sizeof(tmp)) < 0) {
00506             av_log(h, AV_LOG_ERROR, "setsockopt(SO_SNDBUF): %s\n", strerror(errno));
00507             goto fail;
00508         }
00509     } else {
00510         /* set udp recv buffer size to the largest possible udp packet size to
00511          * avoid losing data on OSes that set this too low by default. */
00512         tmp = s->buffer_size;
00513         if (setsockopt(udp_fd, SOL_SOCKET, SO_RCVBUF, &tmp, sizeof(tmp)) < 0) {
00514             av_log(h, AV_LOG_WARNING, "setsockopt(SO_RECVBUF): %s\n", strerror(errno));
00515         }
00516         /* make the socket non-blocking */
00517         ff_socket_nonblock(udp_fd, 1);
00518     }
00519     if (s->is_connected) {
00520         if (connect(udp_fd, (struct sockaddr *) &s->dest_addr, s->dest_addr_len)) {
00521             av_log(h, AV_LOG_ERROR, "connect: %s\n", strerror(errno));
00522             goto fail;
00523         }
00524     }
00525 
00526     s->udp_fd = udp_fd;
00527 
00528 #if HAVE_PTHREADS
00529     if (!is_output && s->circular_buffer_size) {
00530         int ret;
00531 
00532         /* start the task going */
00533         s->fifo = av_fifo_alloc(s->circular_buffer_size);
00534         ret = pthread_mutex_init(&s->mutex, NULL);
00535         if (ret != 0) {
00536             av_log(h, AV_LOG_ERROR, "pthread_mutex_init failed : %s\n", strerror(ret));
00537             goto fail;
00538         }
00539         ret = pthread_cond_init(&s->cond, NULL);
00540         if (ret != 0) {
00541             av_log(h, AV_LOG_ERROR, "pthread_cond_init failed : %s\n", strerror(ret));
00542             goto cond_fail;
00543         }
00544         ret = pthread_create(&s->circular_buffer_thread, NULL, circular_buffer_task, h);
00545         if (ret != 0) {
00546             av_log(h, AV_LOG_ERROR, "pthread_create failed : %s\n", strerror(ret));
00547             goto thread_fail;
00548         }
00549         s->thread_started = 1;
00550     }
00551 #endif
00552 
00553     return 0;
00554 #if HAVE_PTHREADS
00555  thread_fail:
00556     pthread_cond_destroy(&s->cond);
00557  cond_fail:
00558     pthread_mutex_destroy(&s->mutex);
00559 #endif
00560  fail:
00561     if (udp_fd >= 0)
00562         closesocket(udp_fd);
00563     av_fifo_free(s->fifo);
00564     return AVERROR(EIO);
00565 }
00566 
00567 static int udp_read(URLContext *h, uint8_t *buf, int size)
00568 {
00569     UDPContext *s = h->priv_data;
00570     int ret;
00571     int avail;
00572 
00573 #if HAVE_PTHREADS
00574     if (s->fifo) {
00575         pthread_mutex_lock(&s->mutex);
00576         do {
00577             avail = av_fifo_size(s->fifo);
00578             if (avail) { // >=size) {
00579                 uint8_t tmp[4];
00580                 pthread_mutex_unlock(&s->mutex);
00581 
00582                 av_fifo_generic_read(s->fifo, tmp, 4, NULL);
00583                 avail= AV_RL32(tmp);
00584                 if(avail > size){
00585                     av_log(h, AV_LOG_WARNING, "Part of datagram lost due to insufficient buffer size\n");
00586                     avail= size;
00587                 }
00588 
00589                 av_fifo_generic_read(s->fifo, buf, avail, NULL);
00590                 av_fifo_drain(s->fifo, AV_RL32(tmp) - avail);
00591                 return avail;
00592             } else if(s->circular_buffer_error){
00593                 pthread_mutex_unlock(&s->mutex);
00594                 return s->circular_buffer_error;
00595             } else if(h->flags & AVIO_FLAG_NONBLOCK) {
00596                 pthread_mutex_unlock(&s->mutex);
00597                 return AVERROR(EAGAIN);
00598             }
00599             else {
00600                 pthread_cond_wait(&s->cond, &s->mutex);
00601             }
00602         } while( 1);
00603     }
00604 #endif
00605 
00606     if (!(h->flags & AVIO_FLAG_NONBLOCK)) {
00607         ret = ff_network_wait_fd(s->udp_fd, 0);
00608         if (ret < 0)
00609             return ret;
00610     }
00611     ret = recv(s->udp_fd, buf, size, 0);
00612 
00613     return ret < 0 ? ff_neterrno() : ret;
00614 }
00615 
00616 static int udp_write(URLContext *h, const uint8_t *buf, int size)
00617 {
00618     UDPContext *s = h->priv_data;
00619     int ret;
00620 
00621     if (!(h->flags & AVIO_FLAG_NONBLOCK)) {
00622         ret = ff_network_wait_fd(s->udp_fd, 1);
00623         if (ret < 0)
00624             return ret;
00625     }
00626 
00627     if (!s->is_connected) {
00628         ret = sendto (s->udp_fd, buf, size, 0,
00629                       (struct sockaddr *) &s->dest_addr,
00630                       s->dest_addr_len);
00631     } else
00632         ret = send(s->udp_fd, buf, size, 0);
00633 
00634     return ret < 0 ? ff_neterrno() : ret;
00635 }
00636 
00637 static int udp_close(URLContext *h)
00638 {
00639     UDPContext *s = h->priv_data;
00640     int ret;
00641 
00642     if (s->is_multicast && (h->flags & AVIO_FLAG_READ))
00643         udp_leave_multicast_group(s->udp_fd, (struct sockaddr *)&s->dest_addr);
00644     closesocket(s->udp_fd);
00645     av_fifo_free(s->fifo);
00646 #if HAVE_PTHREADS
00647     if (s->thread_started) {
00648         s->exit_thread = 1;
00649         ret = pthread_join(s->circular_buffer_thread, NULL);
00650         if (ret != 0)
00651             av_log(h, AV_LOG_ERROR, "pthread_join(): %s\n", strerror(ret));
00652     }
00653 
00654     pthread_mutex_destroy(&s->mutex);
00655     pthread_cond_destroy(&s->cond);
00656 #endif
00657     return 0;
00658 }
00659 
00660 URLProtocol ff_udp_protocol = {
00661     .name                = "udp",
00662     .url_open            = udp_open,
00663     .url_read            = udp_read,
00664     .url_write           = udp_write,
00665     .url_close           = udp_close,
00666     .url_get_file_handle = udp_get_file_handle,
00667     .priv_data_size      = sizeof(UDPContext),
00668     .flags               = URL_PROTOCOL_FLAG_NETWORK,
00669 };