FFmpeg: libavformat/udp.c Source File

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 #define _DARWIN_C_SOURCE /* Needed for using IP_MULTICAST_TTL on OS X */
00029 #include "avformat.h"
00030 #include <unistd.h>
00031 #include "internal.h"
00032 #include "network.h"
00033 #include "os_support.h"
00034 #if HAVE_SYS_SELECT_H
00035 #include <sys/select.h>
00036 #endif
00037 #include <sys/time.h>
00038 
00039 #ifndef IPV6_ADD_MEMBERSHIP
00040 #define IPV6_ADD_MEMBERSHIP IPV6_JOIN_GROUP
00041 #define IPV6_DROP_MEMBERSHIP IPV6_LEAVE_GROUP
00042 #endif
00043 
00044 typedef struct {
00045     int udp_fd;
00046     int ttl;
00047     int buffer_size;
00048     int is_multicast;
00049     int local_port;
00050     int reuse_socket;
00051     struct sockaddr_storage dest_addr;
00052     int dest_addr_len;
00053     int is_connected;
00054 } UDPContext;
00055 
00056 #define UDP_TX_BUF_SIZE 32768
00057 #define UDP_MAX_PKT_SIZE 65536
00058 
00059 static int udp_set_multicast_ttl(int sockfd, int mcastTTL,
00060                                  struct sockaddr *addr)
00061 {
00062 #ifdef IP_MULTICAST_TTL
00063     if (addr->sa_family == AF_INET) {
00064         if (setsockopt(sockfd, IPPROTO_IP, IP_MULTICAST_TTL, &mcastTTL, sizeof(mcastTTL)) < 0) {
00065             av_log(NULL, AV_LOG_ERROR, "setsockopt(IP_MULTICAST_TTL): %s\n", strerror(errno));
00066             return -1;
00067         }
00068     }
00069 #endif
00070 #if defined(IPPROTO_IPV6) && defined(IPV6_MULTICAST_HOPS)
00071     if (addr->sa_family == AF_INET6) {
00072         if (setsockopt(sockfd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &mcastTTL, sizeof(mcastTTL)) < 0) {
00073             av_log(NULL, AV_LOG_ERROR, "setsockopt(IPV6_MULTICAST_HOPS): %s\n", strerror(errno));
00074             return -1;
00075         }
00076     }
00077 #endif
00078     return 0;
00079 }
00080 
00081 static int udp_join_multicast_group(int sockfd, struct sockaddr *addr)
00082 {
00083 #ifdef IP_ADD_MEMBERSHIP
00084     if (addr->sa_family == AF_INET) {
00085         struct ip_mreq mreq;
00086 
00087         mreq.imr_multiaddr.s_addr = ((struct sockaddr_in *)addr)->sin_addr.s_addr;
00088         mreq.imr_interface.s_addr= INADDR_ANY;
00089         if (setsockopt(sockfd, IPPROTO_IP, IP_ADD_MEMBERSHIP, (const void *)&mreq, sizeof(mreq)) < 0) {
00090             av_log(NULL, AV_LOG_ERROR, "setsockopt(IP_ADD_MEMBERSHIP): %s\n", strerror(errno));
00091             return -1;
00092         }
00093     }
00094 #endif
00095 #if HAVE_STRUCT_IPV6_MREQ && defined(IPPROTO_IPV6)
00096     if (addr->sa_family == AF_INET6) {
00097         struct ipv6_mreq mreq6;
00098 
00099         memcpy(&mreq6.ipv6mr_multiaddr, &(((struct sockaddr_in6 *)addr)->sin6_addr), sizeof(struct in6_addr));
00100         mreq6.ipv6mr_interface= 0;
00101         if (setsockopt(sockfd, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &mreq6, sizeof(mreq6)) < 0) {
00102             av_log(NULL, AV_LOG_ERROR, "setsockopt(IPV6_ADD_MEMBERSHIP): %s\n", strerror(errno));
00103             return -1;
00104         }
00105     }
00106 #endif
00107     return 0;
00108 }
00109 
00110 static int udp_leave_multicast_group(int sockfd, struct sockaddr *addr)
00111 {
00112 #ifdef IP_DROP_MEMBERSHIP
00113     if (addr->sa_family == AF_INET) {
00114         struct ip_mreq mreq;
00115 
00116         mreq.imr_multiaddr.s_addr = ((struct sockaddr_in *)addr)->sin_addr.s_addr;
00117         mreq.imr_interface.s_addr= INADDR_ANY;
00118         if (setsockopt(sockfd, IPPROTO_IP, IP_DROP_MEMBERSHIP, (const void *)&mreq, sizeof(mreq)) < 0) {
00119             av_log(NULL, AV_LOG_ERROR, "setsockopt(IP_DROP_MEMBERSHIP): %s\n", strerror(errno));
00120             return -1;
00121         }
00122     }
00123 #endif
00124 #if HAVE_STRUCT_IPV6_MREQ && defined(IPPROTO_IPV6)
00125     if (addr->sa_family == AF_INET6) {
00126         struct ipv6_mreq mreq6;
00127 
00128         memcpy(&mreq6.ipv6mr_multiaddr, &(((struct sockaddr_in6 *)addr)->sin6_addr), sizeof(struct in6_addr));
00129         mreq6.ipv6mr_interface= 0;
00130         if (setsockopt(sockfd, IPPROTO_IPV6, IPV6_DROP_MEMBERSHIP, &mreq6, sizeof(mreq6)) < 0) {
00131             av_log(NULL, AV_LOG_ERROR, "setsockopt(IPV6_DROP_MEMBERSHIP): %s\n", strerror(errno));
00132             return -1;
00133         }
00134     }
00135 #endif
00136     return 0;
00137 }
00138 
00139 static struct addrinfo* udp_resolve_host(const char *hostname, int port,
00140                                          int type, int family, int flags)
00141 {
00142     struct addrinfo hints, *res = 0;
00143     int error;
00144     char sport[16];
00145     const char *node = 0, *service = "0";
00146 
00147     if (port > 0) {
00148         snprintf(sport, sizeof(sport), "%d", port);
00149         service = sport;
00150     }
00151     if ((hostname) && (hostname[0] != '\0') && (hostname[0] != '?')) {
00152         node = hostname;
00153     }
00154     memset(&hints, 0, sizeof(hints));
00155     hints.ai_socktype = type;
00156     hints.ai_family   = family;
00157     hints.ai_flags = flags;
00158     if ((error = getaddrinfo(node, service, &hints, &res))) {
00159         res = NULL;
00160         av_log(NULL, AV_LOG_ERROR, "udp_resolve_host: %s\n", gai_strerror(error));
00161     }
00162 
00163     return res;
00164 }
00165 
00166 static int udp_set_url(struct sockaddr_storage *addr,
00167                        const char *hostname, int port)
00168 {
00169     struct addrinfo *res0;
00170     int addr_len;
00171 
00172     res0 = udp_resolve_host(hostname, port, SOCK_DGRAM, AF_UNSPEC, 0);
00173     if (res0 == 0) return AVERROR(EIO);
00174     memcpy(addr, res0->ai_addr, res0->ai_addrlen);
00175     addr_len = res0->ai_addrlen;
00176     freeaddrinfo(res0);
00177 
00178     return addr_len;
00179 }
00180 
00181 static int udp_socket_create(UDPContext *s,
00182                              struct sockaddr_storage *addr, int *addr_len)
00183 {
00184     int udp_fd = -1;
00185     struct addrinfo *res0 = NULL, *res = NULL;
00186     int family = AF_UNSPEC;
00187 
00188     if (((struct sockaddr *) &s->dest_addr)->sa_family)
00189         family = ((struct sockaddr *) &s->dest_addr)->sa_family;
00190     res0 = udp_resolve_host(0, s->local_port, SOCK_DGRAM, family, AI_PASSIVE);
00191     if (res0 == 0)
00192         goto fail;
00193     for (res = res0; res; res=res->ai_next) {
00194         udp_fd = socket(res->ai_family, SOCK_DGRAM, 0);
00195         if (udp_fd > 0) break;
00196         av_log(NULL, AV_LOG_ERROR, "socket: %s\n", strerror(errno));
00197     }
00198 
00199     if (udp_fd < 0)
00200         goto fail;
00201 
00202     memcpy(addr, res->ai_addr, res->ai_addrlen);
00203     *addr_len = res->ai_addrlen;
00204 
00205     freeaddrinfo(res0);
00206 
00207     return udp_fd;
00208 
00209  fail:
00210     if (udp_fd >= 0)
00211         closesocket(udp_fd);
00212     if(res0)
00213         freeaddrinfo(res0);
00214     return -1;
00215 }
00216 
00217 static int udp_port(struct sockaddr_storage *addr, int addr_len)
00218 {
00219     char sbuf[sizeof(int)*3+1];
00220 
00221     if (getnameinfo((struct sockaddr *)addr, addr_len, NULL, 0,  sbuf, sizeof(sbuf), NI_NUMERICSERV) != 0) {
00222         av_log(NULL, AV_LOG_ERROR, "getnameinfo: %s\n", strerror(errno));
00223         return -1;
00224     }
00225 
00226     return strtol(sbuf, NULL, 10);
00227 }
00228 
00229 
00245 int udp_set_remote_url(URLContext *h, const char *uri)
00246 {
00247     UDPContext *s = h->priv_data;
00248     char hostname[256], buf[10];
00249     int port;
00250     const char *p;
00251 
00252     av_url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &port, NULL, 0, uri);
00253 
00254     /* set the destination address */
00255     s->dest_addr_len = udp_set_url(&s->dest_addr, hostname, port);
00256     if (s->dest_addr_len < 0) {
00257         return AVERROR(EIO);
00258     }
00259     s->is_multicast = ff_is_multicast_address((struct sockaddr*) &s->dest_addr);
00260     p = strchr(uri, '?');
00261     if (p) {
00262         if (find_info_tag(buf, sizeof(buf), "connect", p)) {
00263             int was_connected = s->is_connected;
00264             s->is_connected = strtol(buf, NULL, 10);
00265             if (s->is_connected && !was_connected) {
00266                 if (connect(s->udp_fd, (struct sockaddr *) &s->dest_addr,
00267                             s->dest_addr_len)) {
00268                     s->is_connected = 0;
00269                     av_log(NULL, AV_LOG_ERROR, "connect: %s\n", strerror(errno));
00270                     return AVERROR(EIO);
00271                 }
00272             }
00273         }
00274     }
00275 
00276     return 0;
00277 }
00278 
00284 int udp_get_local_port(URLContext *h)
00285 {
00286     UDPContext *s = h->priv_data;
00287     return s->local_port;
00288 }
00289 
00295 #if !FF_API_UDP_GET_FILE
00296 static
00297 #endif
00298 int udp_get_file_handle(URLContext *h)
00299 {
00300     UDPContext *s = h->priv_data;
00301     return s->udp_fd;
00302 }
00303 
00304 /* put it in UDP context */
00305 /* return non zero if error */
00306 static int udp_open(URLContext *h, const char *uri, int flags)
00307 {
00308     char hostname[1024];
00309     int port, udp_fd = -1, tmp, bind_ret = -1;
00310     UDPContext *s = NULL;
00311     int is_output;
00312     const char *p;
00313     char buf[256];
00314     struct sockaddr_storage my_addr;
00315     int len;
00316 
00317     h->is_streamed = 1;
00318     h->max_packet_size = 1472;
00319 
00320     is_output = (flags & URL_WRONLY);
00321 
00322     s = av_mallocz(sizeof(UDPContext));
00323     if (!s)
00324         return AVERROR(ENOMEM);
00325 
00326     h->priv_data = s;
00327     s->ttl = 16;
00328     s->buffer_size = is_output ? UDP_TX_BUF_SIZE : UDP_MAX_PKT_SIZE;
00329 
00330     p = strchr(uri, '?');
00331     if (p) {
00332         s->reuse_socket = find_info_tag(buf, sizeof(buf), "reuse", p);
00333         if (find_info_tag(buf, sizeof(buf), "ttl", p)) {
00334             s->ttl = strtol(buf, NULL, 10);
00335         }
00336         if (find_info_tag(buf, sizeof(buf), "localport", p)) {
00337             s->local_port = strtol(buf, NULL, 10);
00338         }
00339         if (find_info_tag(buf, sizeof(buf), "pkt_size", p)) {
00340             h->max_packet_size = strtol(buf, NULL, 10);
00341         }
00342         if (find_info_tag(buf, sizeof(buf), "buffer_size", p)) {
00343             s->buffer_size = strtol(buf, NULL, 10);
00344         }
00345         if (find_info_tag(buf, sizeof(buf), "connect", p)) {
00346             s->is_connected = strtol(buf, NULL, 10);
00347         }
00348     }
00349 
00350     /* fill the dest addr */
00351     av_url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &port, NULL, 0, uri);
00352 
00353     /* XXX: fix av_url_split */
00354     if (hostname[0] == '\0' || hostname[0] == '?') {
00355         /* only accepts null hostname if input */
00356         if (flags & URL_WRONLY)
00357             goto fail;
00358     } else {
00359         if (udp_set_remote_url(h, uri) < 0)
00360             goto fail;
00361     }
00362 
00363     if (s->is_multicast && !(h->flags & URL_WRONLY))
00364         s->local_port = port;
00365     udp_fd = udp_socket_create(s, &my_addr, &len);
00366     if (udp_fd < 0)
00367         goto fail;
00368 
00369     if (s->reuse_socket)
00370         if (setsockopt (udp_fd, SOL_SOCKET, SO_REUSEADDR, &(s->reuse_socket), sizeof(s->reuse_socket)) != 0)
00371             goto fail;
00372 
00373     /* the bind is needed to give a port to the socket now */
00374     /* if multicast, try the multicast address bind first */
00375     if (s->is_multicast && !(h->flags & URL_WRONLY)) {
00376         bind_ret = bind(udp_fd,(struct sockaddr *)&s->dest_addr, len);
00377     }
00378     /* bind to the local address if not multicast or if the multicast
00379      * bind failed */
00380     if (bind_ret < 0 && bind(udp_fd,(struct sockaddr *)&my_addr, len) < 0)
00381         goto fail;
00382 
00383     len = sizeof(my_addr);
00384     getsockname(udp_fd, (struct sockaddr *)&my_addr, &len);
00385     s->local_port = udp_port(&my_addr, len);
00386 
00387     if (s->is_multicast) {
00388         if (h->flags & URL_WRONLY) {
00389             /* output */
00390             if (udp_set_multicast_ttl(udp_fd, s->ttl, (struct sockaddr *)&s->dest_addr) < 0)
00391                 goto fail;
00392         } else {
00393             /* input */
00394             if (udp_join_multicast_group(udp_fd, (struct sockaddr *)&s->dest_addr) < 0)
00395                 goto fail;
00396         }
00397     }
00398 
00399     if (is_output) {
00400         /* limit the tx buf size to limit latency */
00401         tmp = s->buffer_size;
00402         if (setsockopt(udp_fd, SOL_SOCKET, SO_SNDBUF, &tmp, sizeof(tmp)) < 0) {
00403             av_log(NULL, AV_LOG_ERROR, "setsockopt(SO_SNDBUF): %s\n", strerror(errno));
00404             goto fail;
00405         }
00406     } else {
00407         /* set udp recv buffer size to the largest possible udp packet size to
00408          * avoid losing data on OSes that set this too low by default. */
00409         tmp = s->buffer_size;
00410         if (setsockopt(udp_fd, SOL_SOCKET, SO_RCVBUF, &tmp, sizeof(tmp)) < 0) {
00411             av_log(NULL, AV_LOG_WARNING, "setsockopt(SO_RECVBUF): %s\n", strerror(errno));
00412         }
00413         /* make the socket non-blocking */
00414         ff_socket_nonblock(udp_fd, 1);
00415     }
00416     if (s->is_connected) {
00417         if (connect(udp_fd, (struct sockaddr *) &s->dest_addr, s->dest_addr_len)) {
00418             av_log(NULL, AV_LOG_ERROR, "connect: %s\n", strerror(errno));
00419             goto fail;
00420         }
00421     }
00422 
00423     s->udp_fd = udp_fd;
00424     return 0;
00425  fail:
00426     if (udp_fd >= 0)
00427         closesocket(udp_fd);
00428     av_free(s);
00429     return AVERROR(EIO);
00430 }
00431 
00432 static int udp_read(URLContext *h, uint8_t *buf, int size)
00433 {
00434     UDPContext *s = h->priv_data;
00435     int len;
00436     fd_set rfds;
00437     int ret;
00438     struct timeval tv;
00439 
00440     for(;;) {
00441         if (url_interrupt_cb())
00442             return AVERROR(EINTR);
00443         FD_ZERO(&rfds);
00444         FD_SET(s->udp_fd, &rfds);
00445         tv.tv_sec = 0;
00446         tv.tv_usec = 100 * 1000;
00447         ret = select(s->udp_fd + 1, &rfds, NULL, NULL, &tv);
00448         if (ret < 0) {
00449             if (ff_neterrno() == FF_NETERROR(EINTR))
00450                 continue;
00451             return AVERROR(EIO);
00452         }
00453         if (!(ret > 0 && FD_ISSET(s->udp_fd, &rfds)))
00454             continue;
00455         len = recv(s->udp_fd, buf, size, 0);
00456         if (len < 0) {
00457             if (ff_neterrno() != FF_NETERROR(EAGAIN) &&
00458                 ff_neterrno() != FF_NETERROR(EINTR))
00459                 return AVERROR(EIO);
00460         } else {
00461             break;
00462         }
00463     }
00464     return len;
00465 }
00466 
00467 static int udp_write(URLContext *h, const uint8_t *buf, int size)
00468 {
00469     UDPContext *s = h->priv_data;
00470     int ret;
00471 
00472     for(;;) {
00473         if (!s->is_connected) {
00474             ret = sendto (s->udp_fd, buf, size, 0,
00475                           (struct sockaddr *) &s->dest_addr,
00476                           s->dest_addr_len);
00477         } else
00478             ret = send(s->udp_fd, buf, size, 0);
00479         if (ret < 0) {
00480             if (ff_neterrno() != FF_NETERROR(EINTR) &&
00481                 ff_neterrno() != FF_NETERROR(EAGAIN))
00482                 return ff_neterrno();
00483         } else {
00484             break;
00485         }
00486     }
00487     return size;
00488 }
00489 
00490 static int udp_close(URLContext *h)
00491 {
00492     UDPContext *s = h->priv_data;
00493 
00494     if (s->is_multicast && !(h->flags & URL_WRONLY))
00495         udp_leave_multicast_group(s->udp_fd, (struct sockaddr *)&s->dest_addr);
00496     closesocket(s->udp_fd);
00497     av_free(s);
00498     return 0;
00499 }
00500 
00501 URLProtocol udp_protocol = {
00502     "udp",
00503     udp_open,
00504     udp_read,
00505     udp_write,
00506     NULL, /* seek */
00507     udp_close,
00508     .url_get_file_handle = udp_get_file_handle,
00509 };