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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 <unistd.h>
00034 #include "internal.h"
00035 #include "network.h"
00036 #include "os_support.h"
00037 #include "url.h"
00038 
00039 #if HAVE_PTHREADS
00040 #include <pthread.h>
00041 #endif
00042 
00043 #include <sys/time.h>
00044 
00045 #ifndef IPV6_ADD_MEMBERSHIP
00046 #define IPV6_ADD_MEMBERSHIP IPV6_JOIN_GROUP
00047 #define IPV6_DROP_MEMBERSHIP IPV6_LEAVE_GROUP
00048 #endif
00049 
00050 typedef struct {
00051     int udp_fd;
00052     int ttl;
00053     int buffer_size;
00054     int is_multicast;
00055     int local_port;
00056     int reuse_socket;
00057     struct sockaddr_storage dest_addr;
00058     int dest_addr_len;
00059     int is_connected;
00060 
00061     /* Circular Buffer variables for use in UDP receive code */
00062     int circular_buffer_size;
00063     AVFifoBuffer *fifo;
00064     int circular_buffer_error;
00065 #if HAVE_PTHREADS
00066     pthread_t circular_buffer_thread;
00067 #endif
00068 } UDPContext;
00069 
00070 #define UDP_TX_BUF_SIZE 32768
00071 #define UDP_MAX_PKT_SIZE 65536
00072 
00073 static int udp_set_multicast_ttl(int sockfd, int mcastTTL,
00074                                  struct sockaddr *addr)
00075 {
00076 #ifdef IP_MULTICAST_TTL
00077     if (addr->sa_family == AF_INET) {
00078         if (setsockopt(sockfd, IPPROTO_IP, IP_MULTICAST_TTL, &mcastTTL, sizeof(mcastTTL)) < 0) {
00079             av_log(NULL, AV_LOG_ERROR, "setsockopt(IP_MULTICAST_TTL): %s\n", strerror(errno));
00080             return -1;
00081         }
00082     }
00083 #endif
00084 #if defined(IPPROTO_IPV6) && defined(IPV6_MULTICAST_HOPS)
00085     if (addr->sa_family == AF_INET6) {
00086         if (setsockopt(sockfd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &mcastTTL, sizeof(mcastTTL)) < 0) {
00087             av_log(NULL, AV_LOG_ERROR, "setsockopt(IPV6_MULTICAST_HOPS): %s\n", strerror(errno));
00088             return -1;
00089         }
00090     }
00091 #endif
00092     return 0;
00093 }
00094 
00095 static int udp_join_multicast_group(int sockfd, struct sockaddr *addr)
00096 {
00097 #ifdef IP_ADD_MEMBERSHIP
00098     if (addr->sa_family == AF_INET) {
00099         struct ip_mreq mreq;
00100 
00101         mreq.imr_multiaddr.s_addr = ((struct sockaddr_in *)addr)->sin_addr.s_addr;
00102         mreq.imr_interface.s_addr= INADDR_ANY;
00103         if (setsockopt(sockfd, IPPROTO_IP, IP_ADD_MEMBERSHIP, (const void *)&mreq, sizeof(mreq)) < 0) {
00104             av_log(NULL, AV_LOG_ERROR, "setsockopt(IP_ADD_MEMBERSHIP): %s\n", strerror(errno));
00105             return -1;
00106         }
00107     }
00108 #endif
00109 #if HAVE_STRUCT_IPV6_MREQ && defined(IPPROTO_IPV6)
00110     if (addr->sa_family == AF_INET6) {
00111         struct ipv6_mreq mreq6;
00112 
00113         memcpy(&mreq6.ipv6mr_multiaddr, &(((struct sockaddr_in6 *)addr)->sin6_addr), sizeof(struct in6_addr));
00114         mreq6.ipv6mr_interface= 0;
00115         if (setsockopt(sockfd, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &mreq6, sizeof(mreq6)) < 0) {
00116             av_log(NULL, AV_LOG_ERROR, "setsockopt(IPV6_ADD_MEMBERSHIP): %s\n", strerror(errno));
00117             return -1;
00118         }
00119     }
00120 #endif
00121     return 0;
00122 }
00123 
00124 static int udp_leave_multicast_group(int sockfd, struct sockaddr *addr)
00125 {
00126 #ifdef IP_DROP_MEMBERSHIP
00127     if (addr->sa_family == AF_INET) {
00128         struct ip_mreq mreq;
00129 
00130         mreq.imr_multiaddr.s_addr = ((struct sockaddr_in *)addr)->sin_addr.s_addr;
00131         mreq.imr_interface.s_addr= INADDR_ANY;
00132         if (setsockopt(sockfd, IPPROTO_IP, IP_DROP_MEMBERSHIP, (const void *)&mreq, sizeof(mreq)) < 0) {
00133             av_log(NULL, AV_LOG_ERROR, "setsockopt(IP_DROP_MEMBERSHIP): %s\n", strerror(errno));
00134             return -1;
00135         }
00136     }
00137 #endif
00138 #if HAVE_STRUCT_IPV6_MREQ && defined(IPPROTO_IPV6)
00139     if (addr->sa_family == AF_INET6) {
00140         struct ipv6_mreq mreq6;
00141 
00142         memcpy(&mreq6.ipv6mr_multiaddr, &(((struct sockaddr_in6 *)addr)->sin6_addr), sizeof(struct in6_addr));
00143         mreq6.ipv6mr_interface= 0;
00144         if (setsockopt(sockfd, IPPROTO_IPV6, IPV6_DROP_MEMBERSHIP, &mreq6, sizeof(mreq6)) < 0) {
00145             av_log(NULL, AV_LOG_ERROR, "setsockopt(IPV6_DROP_MEMBERSHIP): %s\n", strerror(errno));
00146             return -1;
00147         }
00148     }
00149 #endif
00150     return 0;
00151 }
00152 
00153 static struct addrinfo* udp_resolve_host(const char *hostname, int port,
00154                                          int type, int family, int flags)
00155 {
00156     struct addrinfo hints, *res = 0;
00157     int error;
00158     char sport[16];
00159     const char *node = 0, *service = "0";
00160 
00161     if (port > 0) {
00162         snprintf(sport, sizeof(sport), "%d", port);
00163         service = sport;
00164     }
00165     if ((hostname) && (hostname[0] != '\0') && (hostname[0] != '?')) {
00166         node = hostname;
00167     }
00168     memset(&hints, 0, sizeof(hints));
00169     hints.ai_socktype = type;
00170     hints.ai_family   = family;
00171     hints.ai_flags = flags;
00172     if ((error = getaddrinfo(node, service, &hints, &res))) {
00173         res = NULL;
00174         av_log(NULL, AV_LOG_ERROR, "udp_resolve_host: %s\n", gai_strerror(error));
00175     }
00176 
00177     return res;
00178 }
00179 
00180 static int udp_set_url(struct sockaddr_storage *addr,
00181                        const char *hostname, int port)
00182 {
00183     struct addrinfo *res0;
00184     int addr_len;
00185 
00186     res0 = udp_resolve_host(hostname, port, SOCK_DGRAM, AF_UNSPEC, 0);
00187     if (res0 == 0) return AVERROR(EIO);
00188     memcpy(addr, res0->ai_addr, res0->ai_addrlen);
00189     addr_len = res0->ai_addrlen;
00190     freeaddrinfo(res0);
00191 
00192     return addr_len;
00193 }
00194 
00195 static int udp_socket_create(UDPContext *s,
00196                              struct sockaddr_storage *addr, int *addr_len)
00197 {
00198     int udp_fd = -1;
00199     struct addrinfo *res0 = NULL, *res = NULL;
00200     int family = AF_UNSPEC;
00201 
00202     if (((struct sockaddr *) &s->dest_addr)->sa_family)
00203         family = ((struct sockaddr *) &s->dest_addr)->sa_family;
00204     res0 = udp_resolve_host(0, s->local_port, SOCK_DGRAM, family, AI_PASSIVE);
00205     if (res0 == 0)
00206         goto fail;
00207     for (res = res0; res; res=res->ai_next) {
00208         udp_fd = socket(res->ai_family, SOCK_DGRAM, 0);
00209         if (udp_fd > 0) break;
00210         av_log(NULL, AV_LOG_ERROR, "socket: %s\n", strerror(errno));
00211     }
00212 
00213     if (udp_fd < 0)
00214         goto fail;
00215 
00216     memcpy(addr, res->ai_addr, res->ai_addrlen);
00217     *addr_len = res->ai_addrlen;
00218 
00219     freeaddrinfo(res0);
00220 
00221     return udp_fd;
00222 
00223  fail:
00224     if (udp_fd >= 0)
00225         closesocket(udp_fd);
00226     if(res0)
00227         freeaddrinfo(res0);
00228     return -1;
00229 }
00230 
00231 static int udp_port(struct sockaddr_storage *addr, int addr_len)
00232 {
00233     char sbuf[sizeof(int)*3+1];
00234 
00235     if (getnameinfo((struct sockaddr *)addr, addr_len, NULL, 0,  sbuf, sizeof(sbuf), NI_NUMERICSERV) != 0) {
00236         av_log(NULL, AV_LOG_ERROR, "getnameinfo: %s\n", strerror(errno));
00237         return -1;
00238     }
00239 
00240     return strtol(sbuf, NULL, 10);
00241 }
00242 
00243 
00259 int ff_udp_set_remote_url(URLContext *h, const char *uri)
00260 {
00261     UDPContext *s = h->priv_data;
00262     char hostname[256], buf[10];
00263     int port;
00264     const char *p;
00265 
00266     av_url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &port, NULL, 0, uri);
00267 
00268     /* set the destination address */
00269     s->dest_addr_len = udp_set_url(&s->dest_addr, hostname, port);
00270     if (s->dest_addr_len < 0) {
00271         return AVERROR(EIO);
00272     }
00273     s->is_multicast = ff_is_multicast_address((struct sockaddr*) &s->dest_addr);
00274     p = strchr(uri, '?');
00275     if (p) {
00276         if (av_find_info_tag(buf, sizeof(buf), "connect", p)) {
00277             int was_connected = s->is_connected;
00278             s->is_connected = strtol(buf, NULL, 10);
00279             if (s->is_connected && !was_connected) {
00280                 if (connect(s->udp_fd, (struct sockaddr *) &s->dest_addr,
00281                             s->dest_addr_len)) {
00282                     s->is_connected = 0;
00283                     av_log(NULL, AV_LOG_ERROR, "connect: %s\n", strerror(errno));
00284                     return AVERROR(EIO);
00285                 }
00286             }
00287         }
00288     }
00289 
00290     return 0;
00291 }
00292 
00298 int ff_udp_get_local_port(URLContext *h)
00299 {
00300     UDPContext *s = h->priv_data;
00301     return s->local_port;
00302 }
00303 
00309 #if !FF_API_UDP_GET_FILE
00310 static
00311 #endif
00312 int udp_get_file_handle(URLContext *h)
00313 {
00314     UDPContext *s = h->priv_data;
00315     return s->udp_fd;
00316 }
00317 
00318 static void *circular_buffer_task( void *_URLContext)
00319 {
00320     URLContext *h = _URLContext;
00321     UDPContext *s = h->priv_data;
00322     fd_set rfds;
00323     struct timeval tv;
00324 
00325     for(;;) {
00326         int left;
00327         int ret;
00328         int len;
00329 
00330         if (url_interrupt_cb()) {
00331             s->circular_buffer_error = EINTR;
00332             return NULL;
00333         }
00334 
00335         FD_ZERO(&rfds);
00336         FD_SET(s->udp_fd, &rfds);
00337         tv.tv_sec = 1;
00338         tv.tv_usec = 0;
00339         ret = select(s->udp_fd + 1, &rfds, NULL, NULL, &tv);
00340         if (ret < 0) {
00341             if (ff_neterrno() == AVERROR(EINTR))
00342                 continue;
00343             s->circular_buffer_error = EIO;
00344             return NULL;
00345         }
00346 
00347         if (!(ret > 0 && FD_ISSET(s->udp_fd, &rfds)))
00348             continue;
00349 
00350         /* How much do we have left to the end of the buffer */
00351         /* Whats the minimum we can read so that we dont comletely fill the buffer */
00352         left = av_fifo_space(s->fifo);
00353         left = FFMIN(left, s->fifo->end - s->fifo->wptr);
00354 
00355         /* No Space left, error, what do we do now */
00356         if( !left) {
00357             av_log(h, AV_LOG_ERROR, "circular_buffer: OVERRUN\n");
00358             s->circular_buffer_error = EIO;
00359             return NULL;
00360         }
00361 
00362         len = recv(s->udp_fd, s->fifo->wptr, left, 0);
00363         if (len < 0) {
00364             if (ff_neterrno() != AVERROR(EAGAIN) && ff_neterrno() != AVERROR(EINTR)) {
00365                 s->circular_buffer_error = EIO;
00366                 return NULL;
00367             }
00368         }
00369         s->fifo->wptr += len;
00370         if (s->fifo->wptr >= s->fifo->end)
00371             s->fifo->wptr = s->fifo->buffer;
00372         s->fifo->wndx += len;
00373     }
00374 
00375     return NULL;
00376 }
00377 
00378 /* put it in UDP context */
00379 /* return non zero if error */
00380 static int udp_open(URLContext *h, const char *uri, int flags)
00381 {
00382     char hostname[1024];
00383     int port, udp_fd = -1, tmp, bind_ret = -1;
00384     UDPContext *s = NULL;
00385     int is_output;
00386     const char *p;
00387     char buf[256];
00388     struct sockaddr_storage my_addr;
00389     int len;
00390     int reuse_specified = 0;
00391 
00392     h->is_streamed = 1;
00393     h->max_packet_size = 1472;
00394 
00395     is_output = (flags & AVIO_WRONLY);
00396 
00397     s = av_mallocz(sizeof(UDPContext));
00398     if (!s)
00399         return AVERROR(ENOMEM);
00400 
00401     h->priv_data = s;
00402     s->ttl = 16;
00403     s->buffer_size = is_output ? UDP_TX_BUF_SIZE : UDP_MAX_PKT_SIZE;
00404 
00405     s->circular_buffer_size = 7*188*4096;
00406 
00407     p = strchr(uri, '?');
00408     if (p) {
00409         if (av_find_info_tag(buf, sizeof(buf), "reuse", p)) {
00410             char *endptr=NULL;
00411             s->reuse_socket = strtol(buf, &endptr, 10);
00412             /* assume if no digits were found it is a request to enable it */
00413             if (buf == endptr)
00414                 s->reuse_socket = 1;
00415             reuse_specified = 1;
00416         }
00417         if (av_find_info_tag(buf, sizeof(buf), "ttl", p)) {
00418             s->ttl = strtol(buf, NULL, 10);
00419         }
00420         if (av_find_info_tag(buf, sizeof(buf), "localport", p)) {
00421             s->local_port = strtol(buf, NULL, 10);
00422         }
00423         if (av_find_info_tag(buf, sizeof(buf), "pkt_size", p)) {
00424             h->max_packet_size = strtol(buf, NULL, 10);
00425         }
00426         if (av_find_info_tag(buf, sizeof(buf), "buffer_size", p)) {
00427             s->buffer_size = strtol(buf, NULL, 10);
00428         }
00429         if (av_find_info_tag(buf, sizeof(buf), "connect", p)) {
00430             s->is_connected = strtol(buf, NULL, 10);
00431         }
00432         if (av_find_info_tag(buf, sizeof(buf), "fifo_size", p)) {
00433             s->circular_buffer_size = strtol(buf, NULL, 10)*188;
00434         }
00435     }
00436 
00437     /* fill the dest addr */
00438     av_url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &port, NULL, 0, uri);
00439 
00440     /* XXX: fix av_url_split */
00441     if (hostname[0] == '\0' || hostname[0] == '?') {
00442         /* only accepts null hostname if input */
00443         if (flags & AVIO_WRONLY)
00444             goto fail;
00445     } else {
00446         if (ff_udp_set_remote_url(h, uri) < 0)
00447             goto fail;
00448     }
00449 
00450     if (s->is_multicast && !(h->flags & AVIO_WRONLY))
00451         s->local_port = port;
00452     udp_fd = udp_socket_create(s, &my_addr, &len);
00453     if (udp_fd < 0)
00454         goto fail;
00455 
00456     /* Follow the requested reuse option, unless it's multicast in which
00457      * case enable reuse unless explicitely disabled.
00458      */
00459     if (s->reuse_socket || (s->is_multicast && !reuse_specified)) {
00460         s->reuse_socket = 1;
00461         if (setsockopt (udp_fd, SOL_SOCKET, SO_REUSEADDR, &(s->reuse_socket), sizeof(s->reuse_socket)) != 0)
00462             goto fail;
00463     }
00464 
00465     /* the bind is needed to give a port to the socket now */
00466     /* if multicast, try the multicast address bind first */
00467     if (s->is_multicast && !(h->flags & AVIO_WRONLY)) {
00468         bind_ret = bind(udp_fd,(struct sockaddr *)&s->dest_addr, len);
00469     }
00470     /* bind to the local address if not multicast or if the multicast
00471      * bind failed */
00472     if (bind_ret < 0 && bind(udp_fd,(struct sockaddr *)&my_addr, len) < 0)
00473         goto fail;
00474 
00475     len = sizeof(my_addr);
00476     getsockname(udp_fd, (struct sockaddr *)&my_addr, &len);
00477     s->local_port = udp_port(&my_addr, len);
00478 
00479     if (s->is_multicast) {
00480         if (h->flags & AVIO_WRONLY) {
00481             /* output */
00482             if (udp_set_multicast_ttl(udp_fd, s->ttl, (struct sockaddr *)&s->dest_addr) < 0)
00483                 goto fail;
00484         } else {
00485             /* input */
00486             if (udp_join_multicast_group(udp_fd, (struct sockaddr *)&s->dest_addr) < 0)
00487                 goto fail;
00488         }
00489     }
00490 
00491     if (is_output) {
00492         /* limit the tx buf size to limit latency */
00493         tmp = s->buffer_size;
00494         if (setsockopt(udp_fd, SOL_SOCKET, SO_SNDBUF, &tmp, sizeof(tmp)) < 0) {
00495             av_log(NULL, AV_LOG_ERROR, "setsockopt(SO_SNDBUF): %s\n", strerror(errno));
00496             goto fail;
00497         }
00498     } else {
00499         /* set udp recv buffer size to the largest possible udp packet size to
00500          * avoid losing data on OSes that set this too low by default. */
00501         tmp = s->buffer_size;
00502         if (setsockopt(udp_fd, SOL_SOCKET, SO_RCVBUF, &tmp, sizeof(tmp)) < 0) {
00503             av_log(NULL, AV_LOG_WARNING, "setsockopt(SO_RECVBUF): %s\n", strerror(errno));
00504         }
00505         /* make the socket non-blocking */
00506         ff_socket_nonblock(udp_fd, 1);
00507     }
00508     if (s->is_connected) {
00509         if (connect(udp_fd, (struct sockaddr *) &s->dest_addr, s->dest_addr_len)) {
00510             av_log(NULL, AV_LOG_ERROR, "connect: %s\n", strerror(errno));
00511             goto fail;
00512         }
00513     }
00514 
00515     s->udp_fd = udp_fd;
00516 
00517 #if HAVE_PTHREADS
00518     if (!is_output && s->circular_buffer_size) {
00519         /* start the task going */
00520         s->fifo = av_fifo_alloc(s->circular_buffer_size);
00521         if (pthread_create(&s->circular_buffer_thread, NULL, circular_buffer_task, h)) {
00522             av_log(h, AV_LOG_ERROR, "pthread_create failed\n");
00523             goto fail;
00524         }
00525     }
00526 #endif
00527 
00528     return 0;
00529  fail:
00530     if (udp_fd >= 0)
00531         closesocket(udp_fd);
00532     av_fifo_free(s->fifo);
00533     av_free(s);
00534     return AVERROR(EIO);
00535 }
00536 
00537 static int udp_read(URLContext *h, uint8_t *buf, int size)
00538 {
00539     UDPContext *s = h->priv_data;
00540     int ret;
00541     int avail;
00542     fd_set rfds;
00543     struct timeval tv;
00544 
00545     if (s->fifo) {
00546 
00547         do {
00548             avail = av_fifo_size(s->fifo);
00549             if (avail) { // >=size) {
00550 
00551                 // Maximum amount available
00552                 size = FFMIN( avail, size);
00553                 av_fifo_generic_read(s->fifo, buf, size, NULL);
00554                 return size;
00555             }
00556             else {
00557                 FD_ZERO(&rfds);
00558                 FD_SET(s->udp_fd, &rfds);
00559                 tv.tv_sec = 1;
00560                 tv.tv_usec = 0;
00561                 ret = select(s->udp_fd + 1, &rfds, NULL, NULL, &tv);
00562                 if (ret<0)
00563                     return ret;
00564             }
00565         } while( 1);
00566     }
00567 
00568     if (!(h->flags & AVIO_FLAG_NONBLOCK)) {
00569         ret = ff_network_wait_fd(s->udp_fd, 0);
00570         if (ret < 0)
00571             return ret;
00572     }
00573     ret = recv(s->udp_fd, buf, size, 0);
00574 
00575     return ret < 0 ? ff_neterrno() : ret;
00576 }
00577 
00578 static int udp_write(URLContext *h, const uint8_t *buf, int size)
00579 {
00580     UDPContext *s = h->priv_data;
00581     int ret;
00582 
00583     if (!(h->flags & AVIO_FLAG_NONBLOCK)) {
00584         ret = ff_network_wait_fd(s->udp_fd, 1);
00585         if (ret < 0)
00586             return ret;
00587     }
00588 
00589     if (!s->is_connected) {
00590         ret = sendto (s->udp_fd, buf, size, 0,
00591                       (struct sockaddr *) &s->dest_addr,
00592                       s->dest_addr_len);
00593     } else
00594         ret = send(s->udp_fd, buf, size, 0);
00595 
00596     return ret < 0 ? ff_neterrno() : ret;
00597 }
00598 
00599 static int udp_close(URLContext *h)
00600 {
00601     UDPContext *s = h->priv_data;
00602 
00603     if (s->is_multicast && !(h->flags & AVIO_WRONLY))
00604         udp_leave_multicast_group(s->udp_fd, (struct sockaddr *)&s->dest_addr);
00605     closesocket(s->udp_fd);
00606     av_fifo_free(s->fifo);
00607     av_free(s);
00608     return 0;
00609 }
00610 
00611 URLProtocol ff_udp_protocol = {
00612     .name                = "udp",
00613     .url_open            = udp_open,
00614     .url_read            = udp_read,
00615     .url_write           = udp_write,
00616     .url_close           = udp_close,
00617     .url_get_file_handle = udp_get_file_handle,
00618 };

Generated on Fri Feb 22 2013 07:24:32 for FFmpeg by  doxygen 1.7.1