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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 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 "libavutil/avstring.h"
00033 #include <unistd.h>
00034 #include "internal.h"
00035 #include "network.h"
00036 #include "os_support.h"
00037 #include "url.h"
00038 #include <sys/time.h>
00039 
00040 #ifndef IPV6_ADD_MEMBERSHIP
00041 #define IPV6_ADD_MEMBERSHIP IPV6_JOIN_GROUP
00042 #define IPV6_DROP_MEMBERSHIP IPV6_LEAVE_GROUP
00043 #endif
00044 
00045 typedef struct {
00046     int udp_fd;
00047     int ttl;
00048     int buffer_size;
00049     int is_multicast;
00050     int local_port;
00051     int reuse_socket;
00052     struct sockaddr_storage dest_addr;
00053     int dest_addr_len;
00054     int is_connected;
00055 } UDPContext;
00056 
00057 #define UDP_TX_BUF_SIZE 32768
00058 #define UDP_MAX_PKT_SIZE 65536
00059 
00060 static int udp_set_multicast_ttl(int sockfd, int mcastTTL,
00061                                  struct sockaddr *addr)
00062 {
00063 #ifdef IP_MULTICAST_TTL
00064     if (addr->sa_family == AF_INET) {
00065         if (setsockopt(sockfd, IPPROTO_IP, IP_MULTICAST_TTL, &mcastTTL, sizeof(mcastTTL)) < 0) {
00066             av_log(NULL, AV_LOG_ERROR, "setsockopt(IP_MULTICAST_TTL): %s\n", strerror(errno));
00067             return -1;
00068         }
00069     }
00070 #endif
00071 #if defined(IPPROTO_IPV6) && defined(IPV6_MULTICAST_HOPS)
00072     if (addr->sa_family == AF_INET6) {
00073         if (setsockopt(sockfd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &mcastTTL, sizeof(mcastTTL)) < 0) {
00074             av_log(NULL, AV_LOG_ERROR, "setsockopt(IPV6_MULTICAST_HOPS): %s\n", strerror(errno));
00075             return -1;
00076         }
00077     }
00078 #endif
00079     return 0;
00080 }
00081 
00082 static int udp_join_multicast_group(int sockfd, struct sockaddr *addr)
00083 {
00084 #ifdef IP_ADD_MEMBERSHIP
00085     if (addr->sa_family == AF_INET) {
00086         struct ip_mreq mreq;
00087 
00088         mreq.imr_multiaddr.s_addr = ((struct sockaddr_in *)addr)->sin_addr.s_addr;
00089         mreq.imr_interface.s_addr= INADDR_ANY;
00090         if (setsockopt(sockfd, IPPROTO_IP, IP_ADD_MEMBERSHIP, (const void *)&mreq, sizeof(mreq)) < 0) {
00091             av_log(NULL, AV_LOG_ERROR, "setsockopt(IP_ADD_MEMBERSHIP): %s\n", strerror(errno));
00092             return -1;
00093         }
00094     }
00095 #endif
00096 #if HAVE_STRUCT_IPV6_MREQ && defined(IPPROTO_IPV6)
00097     if (addr->sa_family == AF_INET6) {
00098         struct ipv6_mreq mreq6;
00099 
00100         memcpy(&mreq6.ipv6mr_multiaddr, &(((struct sockaddr_in6 *)addr)->sin6_addr), sizeof(struct in6_addr));
00101         mreq6.ipv6mr_interface= 0;
00102         if (setsockopt(sockfd, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &mreq6, sizeof(mreq6)) < 0) {
00103             av_log(NULL, AV_LOG_ERROR, "setsockopt(IPV6_ADD_MEMBERSHIP): %s\n", strerror(errno));
00104             return -1;
00105         }
00106     }
00107 #endif
00108     return 0;
00109 }
00110 
00111 static int udp_leave_multicast_group(int sockfd, struct sockaddr *addr)
00112 {
00113 #ifdef IP_DROP_MEMBERSHIP
00114     if (addr->sa_family == AF_INET) {
00115         struct ip_mreq mreq;
00116 
00117         mreq.imr_multiaddr.s_addr = ((struct sockaddr_in *)addr)->sin_addr.s_addr;
00118         mreq.imr_interface.s_addr= INADDR_ANY;
00119         if (setsockopt(sockfd, IPPROTO_IP, IP_DROP_MEMBERSHIP, (const void *)&mreq, sizeof(mreq)) < 0) {
00120             av_log(NULL, AV_LOG_ERROR, "setsockopt(IP_DROP_MEMBERSHIP): %s\n", strerror(errno));
00121             return -1;
00122         }
00123     }
00124 #endif
00125 #if HAVE_STRUCT_IPV6_MREQ && defined(IPPROTO_IPV6)
00126     if (addr->sa_family == AF_INET6) {
00127         struct ipv6_mreq mreq6;
00128 
00129         memcpy(&mreq6.ipv6mr_multiaddr, &(((struct sockaddr_in6 *)addr)->sin6_addr), sizeof(struct in6_addr));
00130         mreq6.ipv6mr_interface= 0;
00131         if (setsockopt(sockfd, IPPROTO_IPV6, IPV6_DROP_MEMBERSHIP, &mreq6, sizeof(mreq6)) < 0) {
00132             av_log(NULL, AV_LOG_ERROR, "setsockopt(IPV6_DROP_MEMBERSHIP): %s\n", strerror(errno));
00133             return -1;
00134         }
00135     }
00136 #endif
00137     return 0;
00138 }
00139 
00140 static struct addrinfo* udp_resolve_host(const char *hostname, int port,
00141                                          int type, int family, int flags)
00142 {
00143     struct addrinfo hints, *res = 0;
00144     int error;
00145     char sport[16];
00146     const char *node = 0, *service = "0";
00147 
00148     if (port > 0) {
00149         snprintf(sport, sizeof(sport), "%d", port);
00150         service = sport;
00151     }
00152     if ((hostname) && (hostname[0] != '\0') && (hostname[0] != '?')) {
00153         node = hostname;
00154     }
00155     memset(&hints, 0, sizeof(hints));
00156     hints.ai_socktype = type;
00157     hints.ai_family   = family;
00158     hints.ai_flags = flags;
00159     if ((error = getaddrinfo(node, service, &hints, &res))) {
00160         res = NULL;
00161         av_log(NULL, AV_LOG_ERROR, "udp_resolve_host: %s\n", gai_strerror(error));
00162     }
00163 
00164     return res;
00165 }
00166 
00167 static int udp_set_url(struct sockaddr_storage *addr,
00168                        const char *hostname, int port)
00169 {
00170     struct addrinfo *res0;
00171     int addr_len;
00172 
00173     res0 = udp_resolve_host(hostname, port, SOCK_DGRAM, AF_UNSPEC, 0);
00174     if (res0 == 0) return AVERROR(EIO);
00175     memcpy(addr, res0->ai_addr, res0->ai_addrlen);
00176     addr_len = res0->ai_addrlen;
00177     freeaddrinfo(res0);
00178 
00179     return addr_len;
00180 }
00181 
00182 static int udp_socket_create(UDPContext *s, struct sockaddr_storage *addr,
00183                              int *addr_len, const char *localaddr)
00184 {
00185     int udp_fd = -1;
00186     struct addrinfo *res0 = NULL, *res = NULL;
00187     int family = AF_UNSPEC;
00188 
00189     if (((struct sockaddr *) &s->dest_addr)->sa_family)
00190         family = ((struct sockaddr *) &s->dest_addr)->sa_family;
00191     res0 = udp_resolve_host(localaddr[0] ? localaddr : NULL, s->local_port,
00192                             SOCK_DGRAM, family, AI_PASSIVE);
00193     if (res0 == 0)
00194         goto fail;
00195     for (res = res0; res; res=res->ai_next) {
00196         udp_fd = socket(res->ai_family, SOCK_DGRAM, 0);
00197         if (udp_fd > 0) break;
00198         av_log(NULL, AV_LOG_ERROR, "socket: %s\n", strerror(errno));
00199     }
00200 
00201     if (udp_fd < 0)
00202         goto fail;
00203 
00204     memcpy(addr, res->ai_addr, res->ai_addrlen);
00205     *addr_len = res->ai_addrlen;
00206 
00207     freeaddrinfo(res0);
00208 
00209     return udp_fd;
00210 
00211  fail:
00212     if (udp_fd >= 0)
00213         closesocket(udp_fd);
00214     if(res0)
00215         freeaddrinfo(res0);
00216     return -1;
00217 }
00218 
00219 static int udp_port(struct sockaddr_storage *addr, int addr_len)
00220 {
00221     char sbuf[sizeof(int)*3+1];
00222 
00223     if (getnameinfo((struct sockaddr *)addr, addr_len, NULL, 0,  sbuf, sizeof(sbuf), NI_NUMERICSERV) != 0) {
00224         av_log(NULL, AV_LOG_ERROR, "getnameinfo: %s\n", strerror(errno));
00225         return -1;
00226     }
00227 
00228     return strtol(sbuf, NULL, 10);
00229 }
00230 
00231 
00247 int ff_udp_set_remote_url(URLContext *h, const char *uri)
00248 {
00249     UDPContext *s = h->priv_data;
00250     char hostname[256], buf[10];
00251     int port;
00252     const char *p;
00253 
00254     av_url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &port, NULL, 0, uri);
00255 
00256     /* set the destination address */
00257     s->dest_addr_len = udp_set_url(&s->dest_addr, hostname, port);
00258     if (s->dest_addr_len < 0) {
00259         return AVERROR(EIO);
00260     }
00261     s->is_multicast = ff_is_multicast_address((struct sockaddr*) &s->dest_addr);
00262     p = strchr(uri, '?');
00263     if (p) {
00264         if (av_find_info_tag(buf, sizeof(buf), "connect", p)) {
00265             int was_connected = s->is_connected;
00266             s->is_connected = strtol(buf, NULL, 10);
00267             if (s->is_connected && !was_connected) {
00268                 if (connect(s->udp_fd, (struct sockaddr *) &s->dest_addr,
00269                             s->dest_addr_len)) {
00270                     s->is_connected = 0;
00271                     av_log(h, AV_LOG_ERROR, "connect: %s\n", strerror(errno));
00272                     return AVERROR(EIO);
00273                 }
00274             }
00275         }
00276     }
00277 
00278     return 0;
00279 }
00280 
00286 int ff_udp_get_local_port(URLContext *h)
00287 {
00288     UDPContext *s = h->priv_data;
00289     return s->local_port;
00290 }
00291 
00297 static int udp_get_file_handle(URLContext *h)
00298 {
00299     UDPContext *s = h->priv_data;
00300     return s->udp_fd;
00301 }
00302 
00303 /* put it in UDP context */
00304 /* return non zero if error */
00305 static int udp_open(URLContext *h, const char *uri, int flags)
00306 {
00307     char hostname[1024], localaddr[1024] = "";
00308     int port, udp_fd = -1, tmp, bind_ret = -1;
00309     UDPContext *s = h->priv_data;
00310     int is_output;
00311     const char *p;
00312     char buf[256];
00313     struct sockaddr_storage my_addr;
00314     int len;
00315     int reuse_specified = 0;
00316 
00317     h->is_streamed = 1;
00318     h->max_packet_size = 1472;
00319 
00320     is_output = !(flags & AVIO_FLAG_READ);
00321 
00322     s->ttl = 16;
00323     s->buffer_size = is_output ? UDP_TX_BUF_SIZE : UDP_MAX_PKT_SIZE;
00324 
00325     p = strchr(uri, '?');
00326     if (p) {
00327         if (av_find_info_tag(buf, sizeof(buf), "reuse", p)) {
00328             char *endptr = NULL;
00329             s->reuse_socket = strtol(buf, &endptr, 10);
00330             /* assume if no digits were found it is a request to enable it */
00331             if (buf == endptr)
00332                 s->reuse_socket = 1;
00333             reuse_specified = 1;
00334         }
00335         if (av_find_info_tag(buf, sizeof(buf), "ttl", p)) {
00336             s->ttl = strtol(buf, NULL, 10);
00337         }
00338         if (av_find_info_tag(buf, sizeof(buf), "localport", p)) {
00339             s->local_port = strtol(buf, NULL, 10);
00340         }
00341         if (av_find_info_tag(buf, sizeof(buf), "pkt_size", p)) {
00342             h->max_packet_size = strtol(buf, NULL, 10);
00343         }
00344         if (av_find_info_tag(buf, sizeof(buf), "buffer_size", p)) {
00345             s->buffer_size = strtol(buf, NULL, 10);
00346         }
00347         if (av_find_info_tag(buf, sizeof(buf), "connect", p)) {
00348             s->is_connected = strtol(buf, NULL, 10);
00349         }
00350         if (av_find_info_tag(buf, sizeof(buf), "localaddr", p)) {
00351             av_strlcpy(localaddr, buf, sizeof(localaddr));
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 || !s->local_port) && (h->flags & AVIO_FLAG_READ))
00369         s->local_port = port;
00370     udp_fd = udp_socket_create(s, &my_addr, &len, localaddr);
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 explicitly 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     return AVERROR(EIO);
00439 }
00440 
00441 static int udp_read(URLContext *h, uint8_t *buf, int size)
00442 {
00443     UDPContext *s = h->priv_data;
00444     int ret;
00445 
00446     if (!(h->flags & AVIO_FLAG_NONBLOCK)) {
00447         ret = ff_network_wait_fd(s->udp_fd, 0);
00448         if (ret < 0)
00449             return ret;
00450     }
00451     ret = recv(s->udp_fd, buf, size, 0);
00452     return ret < 0 ? ff_neterrno() : ret;
00453 }
00454 
00455 static int udp_write(URLContext *h, const uint8_t *buf, int size)
00456 {
00457     UDPContext *s = h->priv_data;
00458     int ret;
00459 
00460     if (!(h->flags & AVIO_FLAG_NONBLOCK)) {
00461         ret = ff_network_wait_fd(s->udp_fd, 1);
00462         if (ret < 0)
00463             return ret;
00464     }
00465 
00466     if (!s->is_connected) {
00467         ret = sendto (s->udp_fd, buf, size, 0,
00468                       (struct sockaddr *) &s->dest_addr,
00469                       s->dest_addr_len);
00470     } else
00471         ret = send(s->udp_fd, buf, size, 0);
00472 
00473     return ret < 0 ? ff_neterrno() : ret;
00474 }
00475 
00476 static int udp_close(URLContext *h)
00477 {
00478     UDPContext *s = h->priv_data;
00479 
00480     if (s->is_multicast && (h->flags & AVIO_FLAG_READ))
00481         udp_leave_multicast_group(s->udp_fd, (struct sockaddr *)&s->dest_addr);
00482     closesocket(s->udp_fd);
00483     return 0;
00484 }
00485 
00486 URLProtocol ff_udp_protocol = {
00487     .name                = "udp",
00488     .url_open            = udp_open,
00489     .url_read            = udp_read,
00490     .url_write           = udp_write,
00491     .url_close           = udp_close,
00492     .url_get_file_handle = udp_get_file_handle,
00493     .priv_data_size      = sizeof(UDPContext),
00494     .flags               = URL_PROTOCOL_FLAG_NETWORK,
00495 };
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