Libav 0.7.1
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 Libav.
00006  *
00007  * Libav 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  * Libav 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 Libav; 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 <unistd.h>
00033 #include "internal.h"
00034 #include "network.h"
00035 #include "os_support.h"
00036 #include "url.h"
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 ff_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 (av_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(h, AV_LOG_ERROR, "connect: %s\n", strerror(errno));
00270                     return AVERROR(EIO);
00271                 }
00272             }
00273         }
00274     }
00275 
00276     return 0;
00277 }
00278 
00284 int ff_udp_get_local_port(URLContext *h)
00285 {
00286     UDPContext *s = h->priv_data;
00287     return s->local_port;
00288 }
00289 
00295 static int udp_get_file_handle(URLContext *h)
00296 {
00297     UDPContext *s = h->priv_data;
00298     return s->udp_fd;
00299 }
00300 
00301 /* put it in UDP context */
00302 /* return non zero if error */
00303 static int udp_open(URLContext *h, const char *uri, int flags)
00304 {
00305     char hostname[1024];
00306     int port, udp_fd = -1, tmp, bind_ret = -1;
00307     UDPContext *s = NULL;
00308     int is_output;
00309     const char *p;
00310     char buf[256];
00311     struct sockaddr_storage my_addr;
00312     int len;
00313     int reuse_specified = 0;
00314 
00315     h->is_streamed = 1;
00316     h->max_packet_size = 1472;
00317 
00318     is_output = !(flags & AVIO_FLAG_READ);
00319 
00320     s = av_mallocz(sizeof(UDPContext));
00321     if (!s)
00322         return AVERROR(ENOMEM);
00323 
00324     h->priv_data = s;
00325     s->ttl = 16;
00326     s->buffer_size = is_output ? UDP_TX_BUF_SIZE : UDP_MAX_PKT_SIZE;
00327 
00328     p = strchr(uri, '?');
00329     if (p) {
00330         if (av_find_info_tag(buf, sizeof(buf), "reuse", p)) {
00331             const char *endptr=NULL;
00332             s->reuse_socket = strtol(buf, &endptr, 10);
00333             /* assume if no digits were found it is a request to enable it */
00334             if (buf == endptr)
00335                 s->reuse_socket = 1;
00336             reuse_specified = 1;
00337         }
00338         if (av_find_info_tag(buf, sizeof(buf), "ttl", p)) {
00339             s->ttl = strtol(buf, NULL, 10);
00340         }
00341         if (av_find_info_tag(buf, sizeof(buf), "localport", p)) {
00342             s->local_port = strtol(buf, NULL, 10);
00343         }
00344         if (av_find_info_tag(buf, sizeof(buf), "pkt_size", p)) {
00345             h->max_packet_size = strtol(buf, NULL, 10);
00346         }
00347         if (av_find_info_tag(buf, sizeof(buf), "buffer_size", p)) {
00348             s->buffer_size = strtol(buf, NULL, 10);
00349         }
00350         if (av_find_info_tag(buf, sizeof(buf), "connect", p)) {
00351             s->is_connected = strtol(buf, NULL, 10);
00352         }
00353     }
00354 
00355     /* fill the dest addr */
00356     av_url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &port, NULL, 0, uri);
00357 
00358     /* XXX: fix av_url_split */
00359     if (hostname[0] == '\0' || hostname[0] == '?') {
00360         /* only accepts null hostname if input */
00361         if (!(flags & AVIO_FLAG_READ))
00362             goto fail;
00363     } else {
00364         if (ff_udp_set_remote_url(h, uri) < 0)
00365             goto fail;
00366     }
00367 
00368     if (s->is_multicast && (h->flags & AVIO_FLAG_READ))
00369         s->local_port = port;
00370     udp_fd = udp_socket_create(s, &my_addr, &len);
00371     if (udp_fd < 0)
00372         goto fail;
00373 
00374     /* Follow the requested reuse option, unless it's multicast in which
00375      * case enable reuse unless explicitely disabled.
00376      */
00377     if (s->reuse_socket || (s->is_multicast && !reuse_specified)) {
00378         s->reuse_socket = 1;
00379         if (setsockopt (udp_fd, SOL_SOCKET, SO_REUSEADDR, &(s->reuse_socket), sizeof(s->reuse_socket)) != 0)
00380             goto fail;
00381     }
00382 
00383     /* the bind is needed to give a port to the socket now */
00384     /* if multicast, try the multicast address bind first */
00385     if (s->is_multicast && (h->flags & AVIO_FLAG_READ)) {
00386         bind_ret = bind(udp_fd,(struct sockaddr *)&s->dest_addr, len);
00387     }
00388     /* bind to the local address if not multicast or if the multicast
00389      * bind failed */
00390     if (bind_ret < 0 && bind(udp_fd,(struct sockaddr *)&my_addr, len) < 0)
00391         goto fail;
00392 
00393     len = sizeof(my_addr);
00394     getsockname(udp_fd, (struct sockaddr *)&my_addr, &len);
00395     s->local_port = udp_port(&my_addr, len);
00396 
00397     if (s->is_multicast) {
00398         if (!(h->flags & AVIO_FLAG_READ)) {
00399             /* output */
00400             if (udp_set_multicast_ttl(udp_fd, s->ttl, (struct sockaddr *)&s->dest_addr) < 0)
00401                 goto fail;
00402         } else {
00403             /* input */
00404             if (udp_join_multicast_group(udp_fd, (struct sockaddr *)&s->dest_addr) < 0)
00405                 goto fail;
00406         }
00407     }
00408 
00409     if (is_output) {
00410         /* limit the tx buf size to limit latency */
00411         tmp = s->buffer_size;
00412         if (setsockopt(udp_fd, SOL_SOCKET, SO_SNDBUF, &tmp, sizeof(tmp)) < 0) {
00413             av_log(h, AV_LOG_ERROR, "setsockopt(SO_SNDBUF): %s\n", strerror(errno));
00414             goto fail;
00415         }
00416     } else {
00417         /* set udp recv buffer size to the largest possible udp packet size to
00418          * avoid losing data on OSes that set this too low by default. */
00419         tmp = s->buffer_size;
00420         if (setsockopt(udp_fd, SOL_SOCKET, SO_RCVBUF, &tmp, sizeof(tmp)) < 0) {
00421             av_log(h, AV_LOG_WARNING, "setsockopt(SO_RECVBUF): %s\n", strerror(errno));
00422         }
00423         /* make the socket non-blocking */
00424         ff_socket_nonblock(udp_fd, 1);
00425     }
00426     if (s->is_connected) {
00427         if (connect(udp_fd, (struct sockaddr *) &s->dest_addr, s->dest_addr_len)) {
00428             av_log(h, AV_LOG_ERROR, "connect: %s\n", strerror(errno));
00429             goto fail;
00430         }
00431     }
00432 
00433     s->udp_fd = udp_fd;
00434     return 0;
00435  fail:
00436     if (udp_fd >= 0)
00437         closesocket(udp_fd);
00438     av_free(s);
00439     return AVERROR(EIO);
00440 }
00441 
00442 static int udp_read(URLContext *h, uint8_t *buf, int size)
00443 {
00444     UDPContext *s = h->priv_data;
00445     int ret;
00446 
00447     if (!(h->flags & AVIO_FLAG_NONBLOCK)) {
00448         ret = ff_network_wait_fd(s->udp_fd, 0);
00449         if (ret < 0)
00450             return ret;
00451     }
00452     ret = recv(s->udp_fd, buf, size, 0);
00453     return ret < 0 ? ff_neterrno() : ret;
00454 }
00455 
00456 static int udp_write(URLContext *h, const uint8_t *buf, int size)
00457 {
00458     UDPContext *s = h->priv_data;
00459     int ret;
00460 
00461     if (!(h->flags & AVIO_FLAG_NONBLOCK)) {
00462         ret = ff_network_wait_fd(s->udp_fd, 1);
00463         if (ret < 0)
00464             return ret;
00465     }
00466 
00467     if (!s->is_connected) {
00468         ret = sendto (s->udp_fd, buf, size, 0,
00469                       (struct sockaddr *) &s->dest_addr,
00470                       s->dest_addr_len);
00471     } else
00472         ret = send(s->udp_fd, buf, size, 0);
00473 
00474     return ret < 0 ? ff_neterrno() : ret;
00475 }
00476 
00477 static int udp_close(URLContext *h)
00478 {
00479     UDPContext *s = h->priv_data;
00480 
00481     if (s->is_multicast && (h->flags & AVIO_FLAG_READ))
00482         udp_leave_multicast_group(s->udp_fd, (struct sockaddr *)&s->dest_addr);
00483     closesocket(s->udp_fd);
00484     av_free(s);
00485     return 0;
00486 }
00487 
00488 URLProtocol ff_udp_protocol = {
00489     .name                = "udp",
00490     .url_open            = udp_open,
00491     .url_read            = udp_read,
00492     .url_write           = udp_write,
00493     .url_close           = udp_close,
00494     .url_get_file_handle = udp_get_file_handle,
00495 };