Example #1
0
static int udp_leave_multicast_group(int sockfd, struct sockaddr *addr,struct sockaddr *local_addr)
{
#ifdef IP_DROP_MEMBERSHIP
    if (addr->sa_family == AF_INET) {
        struct ip_mreq mreq;

        mreq.imr_multiaddr.s_addr = ((struct sockaddr_in *)addr)->sin_addr.s_addr;
        if (local_addr)
            mreq.imr_interface= ((struct sockaddr_in *)local_addr)->sin_addr;
        else
            mreq.imr_interface.s_addr= INADDR_ANY;
        if (setsockopt(sockfd, IPPROTO_IP, IP_DROP_MEMBERSHIP, (const void *)&mreq, sizeof(mreq)) < 0) {
            log_net_error(NULL, AV_LOG_ERROR, "setsockopt(IP_DROP_MEMBERSHIP)");
            return -1;
        }
    }
#endif
#if HAVE_STRUCT_IPV6_MREQ && defined(IPPROTO_IPV6)
    if (addr->sa_family == AF_INET6) {
        struct ipv6_mreq mreq6;

        memcpy(&mreq6.ipv6mr_multiaddr, &(((struct sockaddr_in6 *)addr)->sin6_addr), sizeof(struct in6_addr));
        mreq6.ipv6mr_interface= 0;
        if (setsockopt(sockfd, IPPROTO_IPV6, IPV6_DROP_MEMBERSHIP, &mreq6, sizeof(mreq6)) < 0) {
            log_net_error(NULL, AV_LOG_ERROR, "setsockopt(IPV6_DROP_MEMBERSHIP)");
            return -1;
        }
    }
#endif
    return 0;
}
Example #2
0
/**
 * If no filename is given to av_open_input_file because you want to
 * get the local port first, then you must call this function to set
 * the remote server address.
 *
 * url syntax: udp://host:port[?option=val...]
 * option: 'ttl=n'       : set the ttl value (for multicast only)
 *         'localport=n' : set the local port
 *         'pkt_size=n'  : set max packet size
 *         'reuse=1'     : enable reusing the socket
 *         'overrun_nonfatal=1': survive in case of circular buffer overrun
 *
 * @param h media file context
 * @param uri of the remote server
 * @return zero if no error.
 */
int ff_udp_set_remote_url(URLContext *h, const char *uri)
{
    UDPContext *s = h->priv_data;
    char hostname[256], buf[10];
    int port;
    const char *p;

    av_url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &port, NULL, 0, uri);

    /* set the destination address */
    s->dest_addr_len = udp_set_url(&s->dest_addr, hostname, port);
    if (s->dest_addr_len < 0) {
        return AVERROR(EIO);
    }
    s->is_multicast = ff_is_multicast_address((struct sockaddr*) &s->dest_addr);
    p = strchr(uri, '?');
    if (p) {
        if (av_find_info_tag(buf, sizeof(buf), "connect", p)) {
            int was_connected = s->is_connected;
            s->is_connected = strtol(buf, NULL, 10);
            if (s->is_connected && !was_connected) {
                if (connect(s->udp_fd, (struct sockaddr *) &s->dest_addr,
                            s->dest_addr_len)) {
                    s->is_connected = 0;
                    log_net_error(h, AV_LOG_ERROR, "connect");
                    return AVERROR(EIO);
                }
            }
        }
    }

    return 0;
}
Example #3
0
static int udp_socket_create(int local_port, struct sockaddr_storage *addr,
                             socklen_t *addr_len, const char *localaddr)
{
    int udp_fd = -1;
    struct addrinfo *res0 = NULL, *res = NULL;
    int family = AF_UNSPEC;

    res0 = udp_resolve_host(localaddr[0] ? localaddr : NULL, local_port,
                            SOCK_DGRAM, family, AI_PASSIVE);
    if (res0 == 0)
        goto fail;
    for (res = res0; res; res=res->ai_next) {
        udp_fd = socket(res->ai_family, SOCK_DGRAM, 0);
        if (udp_fd != -1) break;
        log_net_error(NULL, AV_LOG_ERROR, "socket");
    }

    if (udp_fd < 0)
        goto fail;

    memcpy(addr, res->ai_addr, res->ai_addrlen);
    *addr_len = res->ai_addrlen;

    freeaddrinfo(res0);

    return udp_fd;

 fail:
    if (udp_fd >= 0)
        closesocket(udp_fd);
    if(res0)
        freeaddrinfo(res0);
    return -1;
}
Example #4
0
static int udp_set_multicast_ttl(int sockfd, int mcastTTL,
                                 struct sockaddr *addr)
{
#ifdef IP_MULTICAST_TTL
    if (addr->sa_family == AF_INET) {
        if (setsockopt(sockfd, IPPROTO_IP, IP_MULTICAST_TTL, &mcastTTL, sizeof(mcastTTL)) < 0) {
            log_net_error(NULL, AV_LOG_ERROR, "setsockopt(IP_MULTICAST_TTL)");
            return -1;
        }
    }
#endif
#if defined(IPPROTO_IPV6) && defined(IPV6_MULTICAST_HOPS)
    if (addr->sa_family == AF_INET6) {
        if (setsockopt(sockfd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &mcastTTL, sizeof(mcastTTL)) < 0) {
            log_net_error(NULL, AV_LOG_ERROR, "setsockopt(IPV6_MULTICAST_HOPS)");
            return -1;
        }
    }
#endif
    return 0;
}
Example #5
0
static int udp_socket_create(URLContext *h, struct sockaddr_storage *addr,
                             socklen_t *addr_len, const char *localaddr)
{
    UDPContext *s = h->priv_data;
    int udp_fd = -1;
    struct addrinfo *res0, *res;
    int family = AF_UNSPEC;

    if (((struct sockaddr *) &s->dest_addr)->sa_family)
        family = ((struct sockaddr *) &s->dest_addr)->sa_family;
    res0 = udp_resolve_host(h, (localaddr && localaddr[0]) ? localaddr : NULL,
                            s->local_port,
                            SOCK_DGRAM, family, AI_PASSIVE);
    if (!res0)
        goto fail;
    for (res = res0; res; res=res->ai_next) {
        if (s->udplite_coverage)
            udp_fd = ff_socket(res->ai_family, SOCK_DGRAM, IPPROTO_UDPLITE);
        else
            udp_fd = ff_socket(res->ai_family, SOCK_DGRAM, 0);
        if (udp_fd != -1) break;
        log_net_error(NULL, AV_LOG_ERROR, "socket");
    }

    if (udp_fd < 0)
        goto fail;

    memcpy(addr, res->ai_addr, res->ai_addrlen);
    *addr_len = res->ai_addrlen;

    freeaddrinfo(res0);

    return udp_fd;

 fail:
    if (udp_fd >= 0)
        closesocket(udp_fd);
    if(res0)
        freeaddrinfo(res0);
    return -1;
}
Example #6
0
/* return non zero if error */
static int udp_open(URLContext *h, const char *uri, int flags)
{
    char hostname[1024], localaddr[1024] = "";
    int port, udp_fd = -1, tmp, bind_ret = -1, dscp = -1;
    UDPContext *s = h->priv_data;
    int is_output;
    const char *p;
    char buf[256];
    struct sockaddr_storage my_addr;
    socklen_t len;
    int i, num_include_sources = 0, num_exclude_sources = 0;
    char *include_sources[32], *exclude_sources[32];

    h->is_streamed = 1;

    is_output = !(flags & AVIO_FLAG_READ);
    if (s->buffer_size < 0)
        s->buffer_size = is_output ? UDP_TX_BUF_SIZE : UDP_MAX_PKT_SIZE;

    if (s->sources) {
        if (parse_source_list(s->sources, include_sources,
                              &num_include_sources,
                              FF_ARRAY_ELEMS(include_sources)))
            goto fail;
    }

    if (s->block) {
        if (parse_source_list(s->block, exclude_sources, &num_exclude_sources,
                              FF_ARRAY_ELEMS(exclude_sources)))
            goto fail;
    }

    if (s->pkt_size > 0)
        h->max_packet_size = s->pkt_size;

    p = strchr(uri, '?');
    if (p) {
        if (av_find_info_tag(buf, sizeof(buf), "reuse", p)) {
            char *endptr = NULL;
            s->reuse_socket = strtol(buf, &endptr, 10);
            /* assume if no digits were found it is a request to enable it */
            if (buf == endptr)
                s->reuse_socket = 1;
        }
        if (av_find_info_tag(buf, sizeof(buf), "overrun_nonfatal", p)) {
            char *endptr = NULL;
            s->overrun_nonfatal = strtol(buf, &endptr, 10);
            /* assume if no digits were found it is a request to enable it */
            if (buf == endptr)
                s->overrun_nonfatal = 1;
            if (!HAVE_PTHREAD_CANCEL)
                av_log(h, AV_LOG_WARNING,
                       "'overrun_nonfatal' option was set but it is not supported "
                       "on this build (pthread support is required)\n");
        }
        if (av_find_info_tag(buf, sizeof(buf), "ttl", p)) {
            s->ttl = strtol(buf, NULL, 10);
        }
        if (av_find_info_tag(buf, sizeof(buf), "udplite_coverage", p)) {
            s->udplite_coverage = strtol(buf, NULL, 10);
        }
        if (av_find_info_tag(buf, sizeof(buf), "localport", p)) {
            s->local_port = strtol(buf, NULL, 10);
        }
        if (av_find_info_tag(buf, sizeof(buf), "pkt_size", p)) {
            s->pkt_size = strtol(buf, NULL, 10);
        }
        if (av_find_info_tag(buf, sizeof(buf), "buffer_size", p)) {
            s->buffer_size = strtol(buf, NULL, 10);
        }
        if (av_find_info_tag(buf, sizeof(buf), "connect", p)) {
            s->is_connected = strtol(buf, NULL, 10);
        }
        if (av_find_info_tag(buf, sizeof(buf), "dscp", p)) {
            dscp = strtol(buf, NULL, 10);
        }
        if (av_find_info_tag(buf, sizeof(buf), "fifo_size", p)) {
            s->circular_buffer_size = strtol(buf, NULL, 10);
            if (!HAVE_PTHREAD_CANCEL)
                av_log(h, AV_LOG_WARNING,
                       "'circular_buffer_size' option was set but it is not supported "
                       "on this build (pthread support is required)\n");
        }
        if (av_find_info_tag(buf, sizeof(buf), "localaddr", p)) {
            av_strlcpy(localaddr, buf, sizeof(localaddr));
        }
        if (av_find_info_tag(buf, sizeof(buf), "sources", p)) {
            if (parse_source_list(buf, include_sources, &num_include_sources,
                                  FF_ARRAY_ELEMS(include_sources)))
                goto fail;
        }
        if (av_find_info_tag(buf, sizeof(buf), "block", p)) {
            if (parse_source_list(buf, exclude_sources, &num_exclude_sources,
                                  FF_ARRAY_ELEMS(exclude_sources)))
                goto fail;
        }
        if (!is_output && av_find_info_tag(buf, sizeof(buf), "timeout", p))
            s->timeout = strtol(buf, NULL, 10);
        if (is_output && av_find_info_tag(buf, sizeof(buf), "broadcast", p))
            s->is_broadcast = strtol(buf, NULL, 10);
    }
    /* handling needed to support options picking from both AVOption and URL */
    s->circular_buffer_size *= 188;
    if (flags & AVIO_FLAG_WRITE) {
        h->max_packet_size = s->pkt_size;
    } else {
        h->max_packet_size = UDP_MAX_PKT_SIZE;
    }
    h->rw_timeout = s->timeout;

    /* fill the dest addr */
    av_url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &port, NULL, 0, uri);

    /* XXX: fix av_url_split */
    if (hostname[0] == '\0' || hostname[0] == '?') {
        /* only accepts null hostname if input */
        if (!(flags & AVIO_FLAG_READ))
            goto fail;
    } else {
        if (ff_udp_set_remote_url(h, uri) < 0)
            goto fail;
    }

    if ((s->is_multicast || s->local_port <= 0) && (h->flags & AVIO_FLAG_READ))
        s->local_port = port;

    if (localaddr[0])
        udp_fd = udp_socket_create(s, &my_addr, &len, localaddr);
    else
        udp_fd = udp_socket_create(s, &my_addr, &len, s->localaddr);
    if (udp_fd < 0)
        goto fail;

    s->local_addr_storage=my_addr; //store for future multicast join

    /* Follow the requested reuse option, unless it's multicast in which
     * case enable reuse unless explicitly disabled.
     */
    if (s->reuse_socket > 0 || (s->is_multicast && s->reuse_socket < 0)) {
        s->reuse_socket = 1;
        if (setsockopt (udp_fd, SOL_SOCKET, SO_REUSEADDR, &(s->reuse_socket), sizeof(s->reuse_socket)) != 0)
            goto fail;
    }

    if (s->is_broadcast) {
#ifdef SO_BROADCAST
        if (setsockopt (udp_fd, SOL_SOCKET, SO_BROADCAST, &(s->is_broadcast), sizeof(s->is_broadcast)) != 0)
#endif
           goto fail;
    }

    /* Set the checksum coverage for UDP-Lite (RFC 3828) for sending and receiving.
     * The receiver coverage has to be less than or equal to the sender coverage.
     * Otherwise, the receiver will drop all packets.
     */
    if (s->udplite_coverage) {
        if (setsockopt (udp_fd, IPPROTO_UDPLITE, UDPLITE_SEND_CSCOV, &(s->udplite_coverage), sizeof(s->udplite_coverage)) != 0)
            av_log(h, AV_LOG_WARNING, "socket option UDPLITE_SEND_CSCOV not available");

        if (setsockopt (udp_fd, IPPROTO_UDPLITE, UDPLITE_RECV_CSCOV, &(s->udplite_coverage), sizeof(s->udplite_coverage)) != 0)
            av_log(h, AV_LOG_WARNING, "socket option UDPLITE_RECV_CSCOV not available");
    }

    if (dscp >= 0) {
        dscp <<= 2;
        if (setsockopt (udp_fd, IPPROTO_IP, IP_TOS, &dscp, sizeof(dscp)) != 0)
            goto fail;
    }

    /* If multicast, try binding the multicast address first, to avoid
     * receiving UDP packets from other sources aimed at the same UDP
     * port. This fails on windows. This makes sending to the same address
     * using sendto() fail, so only do it if we're opened in read-only mode. */
    if (s->is_multicast && !(h->flags & AVIO_FLAG_WRITE)) {
        bind_ret = bind(udp_fd,(struct sockaddr *)&s->dest_addr, len);
    }
    /* bind to the local address if not multicast or if the multicast
     * bind failed */
    /* the bind is needed to give a port to the socket now */
    if (bind_ret < 0 && bind(udp_fd,(struct sockaddr *)&my_addr, len) < 0) {
        log_net_error(h, AV_LOG_ERROR, "bind failed");
        goto fail;
    }

    len = sizeof(my_addr);
    getsockname(udp_fd, (struct sockaddr *)&my_addr, &len);
    s->local_port = udp_port(&my_addr, len);

    if (s->is_multicast) {
        if (h->flags & AVIO_FLAG_WRITE) {
            /* output */
            if (udp_set_multicast_ttl(udp_fd, s->ttl, (struct sockaddr *)&s->dest_addr) < 0)
                goto fail;
        }
        if (h->flags & AVIO_FLAG_READ) {
            /* input */
            if (num_include_sources && num_exclude_sources) {
                av_log(h, AV_LOG_ERROR, "Simultaneously including and excluding multicast sources is not supported\n");
                goto fail;
            }
            if (num_include_sources) {
                if (udp_set_multicast_sources(udp_fd, (struct sockaddr *)&s->dest_addr, s->dest_addr_len, include_sources, num_include_sources, 1) < 0)
                    goto fail;
            } else {
                if (udp_join_multicast_group(udp_fd, (struct sockaddr *)&s->dest_addr,(struct sockaddr *)&s->local_addr_storage) < 0)
                    goto fail;
            }
            if (num_exclude_sources) {
                if (udp_set_multicast_sources(udp_fd, (struct sockaddr *)&s->dest_addr, s->dest_addr_len, exclude_sources, num_exclude_sources, 0) < 0)
                    goto fail;
            }
        }
    }

    if (is_output) {
        /* limit the tx buf size to limit latency */
        tmp = s->buffer_size;
        if (setsockopt(udp_fd, SOL_SOCKET, SO_SNDBUF, &tmp, sizeof(tmp)) < 0) {
            log_net_error(h, AV_LOG_ERROR, "setsockopt(SO_SNDBUF)");
            goto fail;
        }
    } else {
        /* set udp recv buffer size to the requested value (default 64K) */
        tmp = s->buffer_size;
        if (setsockopt(udp_fd, SOL_SOCKET, SO_RCVBUF, &tmp, sizeof(tmp)) < 0) {
            log_net_error(h, AV_LOG_WARNING, "setsockopt(SO_RECVBUF)");
        }
        len = sizeof(tmp);
        if (getsockopt(udp_fd, SOL_SOCKET, SO_RCVBUF, &tmp, &len) < 0) {
            log_net_error(h, AV_LOG_WARNING, "getsockopt(SO_RCVBUF)");
        } else {
            av_log(h, AV_LOG_DEBUG, "end receive buffer size reported is %d\n", tmp);
            if(tmp < s->buffer_size)
                av_log(h, AV_LOG_WARNING, "attempted to set receive buffer to size %d but it only ended up set as %d", s->buffer_size, tmp);
        }

        /* make the socket non-blocking */
        ff_socket_nonblock(udp_fd, 1);
    }
    if (s->is_connected) {
        if (connect(udp_fd, (struct sockaddr *) &s->dest_addr, s->dest_addr_len)) {
            log_net_error(h, AV_LOG_ERROR, "connect");
            goto fail;
        }
    }

    for (i = 0; i < num_include_sources; i++)
        av_freep(&include_sources[i]);
    for (i = 0; i < num_exclude_sources; i++)
        av_freep(&exclude_sources[i]);

    s->udp_fd = udp_fd;

#if HAVE_PTHREAD_CANCEL
    if (!is_output && s->circular_buffer_size) {
        int ret;

        /* start the task going */
        s->fifo = av_fifo_alloc(s->circular_buffer_size);
        ret = pthread_mutex_init(&s->mutex, NULL);
        if (ret != 0) {
            av_log(h, AV_LOG_ERROR, "pthread_mutex_init failed : %s\n", strerror(ret));
            goto fail;
        }
        ret = pthread_cond_init(&s->cond, NULL);
        if (ret != 0) {
            av_log(h, AV_LOG_ERROR, "pthread_cond_init failed : %s\n", strerror(ret));
            goto cond_fail;
        }
        ret = pthread_create(&s->circular_buffer_thread, NULL, circular_buffer_task, h);
        if (ret != 0) {
            av_log(h, AV_LOG_ERROR, "pthread_create failed : %s\n", strerror(ret));
            goto thread_fail;
        }
        s->thread_started = 1;
    }
#endif

    return 0;
#if HAVE_PTHREAD_CANCEL
 thread_fail:
    pthread_cond_destroy(&s->cond);
 cond_fail:
    pthread_mutex_destroy(&s->mutex);
#endif
 fail:
    if (udp_fd >= 0)
        closesocket(udp_fd);
    av_fifo_freep(&s->fifo);
    for (i = 0; i < num_include_sources; i++)
        av_freep(&include_sources[i]);
    for (i = 0; i < num_exclude_sources; i++)
        av_freep(&exclude_sources[i]);
    return AVERROR(EIO);
}
Example #7
0
static int udp_set_multicast_sources(int sockfd, struct sockaddr *addr,
                                     int addr_len, char **sources,
                                     int nb_sources, int include)
{
#if HAVE_STRUCT_GROUP_SOURCE_REQ && defined(MCAST_BLOCK_SOURCE) && !defined(_WIN32)
    /* These ones are available in the microsoft SDK, but don't seem to work
     * as on linux, so just prefer the v4-only approach there for now. */
    int i;
    for (i = 0; i < nb_sources; i++) {
        struct group_source_req mreqs;
        int level = addr->sa_family == AF_INET ? IPPROTO_IP : IPPROTO_IPV6;
        struct addrinfo *sourceaddr = udp_resolve_host(sources[i], 0,
                                                       SOCK_DGRAM, AF_UNSPEC,
                                                       0);
        if (!sourceaddr)
            return AVERROR(ENOENT);

        mreqs.gsr_interface = 0;
        memcpy(&mreqs.gsr_group, addr, addr_len);
        memcpy(&mreqs.gsr_source, sourceaddr->ai_addr, sourceaddr->ai_addrlen);
        freeaddrinfo(sourceaddr);

        if (setsockopt(sockfd, level,
                       include ? MCAST_JOIN_SOURCE_GROUP : MCAST_BLOCK_SOURCE,
                       (const void *)&mreqs, sizeof(mreqs)) < 0) {
            if (include)
                log_net_error(NULL, AV_LOG_ERROR, "setsockopt(MCAST_JOIN_SOURCE_GROUP)");
            else
                log_net_error(NULL, AV_LOG_ERROR, "setsockopt(MCAST_BLOCK_SOURCE)");
            return ff_neterrno();
        }
    }
#elif HAVE_STRUCT_IP_MREQ_SOURCE && defined(IP_BLOCK_SOURCE)
    int i;
    if (addr->sa_family != AF_INET) {
        av_log(NULL, AV_LOG_ERROR,
               "Setting multicast sources only supported for IPv4\n");
        return AVERROR(EINVAL);
    }
    for (i = 0; i < nb_sources; i++) {
        struct ip_mreq_source mreqs;
        struct addrinfo *sourceaddr = udp_resolve_host(sources[i], 0,
                                                       SOCK_DGRAM, AF_UNSPEC,
                                                       0);
        if (!sourceaddr)
            return AVERROR(ENOENT);
        if (sourceaddr->ai_addr->sa_family != AF_INET) {
            freeaddrinfo(sourceaddr);
            av_log(NULL, AV_LOG_ERROR, "%s is of incorrect protocol family\n",
                   sources[i]);
            return AVERROR(EINVAL);
        }

        mreqs.imr_multiaddr.s_addr = ((struct sockaddr_in *)addr)->sin_addr.s_addr;
        mreqs.imr_interface.s_addr = INADDR_ANY;
        mreqs.imr_sourceaddr.s_addr = ((struct sockaddr_in *)sourceaddr->ai_addr)->sin_addr.s_addr;
        freeaddrinfo(sourceaddr);

        if (setsockopt(sockfd, IPPROTO_IP,
                       include ? IP_ADD_SOURCE_MEMBERSHIP : IP_BLOCK_SOURCE,
                       (const void *)&mreqs, sizeof(mreqs)) < 0) {
            if (include)
                log_net_error(NULL, AV_LOG_ERROR, "setsockopt(IP_ADD_SOURCE_MEMBERSHIP)");
            else
                log_net_error(NULL, AV_LOG_ERROR, "setsockopt(IP_BLOCK_SOURCE)");
            return ff_neterrno();
        }
    }
#else
    return AVERROR(ENOSYS);
#endif
    return 0;
}
Example #8
0
/* return non zero if error */
static int udp_open(URLContext *h, const char *uri, int flags)
{
    char hostname[1024], localaddr[1024] = "";
    int port, udp_fd = -1, tmp, bind_ret = -1;
    UDPContext *s = h->priv_data;
    int is_output;
    const char *p;
    char buf[256];
    struct sockaddr_storage my_addr;
    socklen_t len;
    int reuse_specified = 0;
    int i, num_include_sources = 0, num_exclude_sources = 0;
    char *include_sources[32], *exclude_sources[32];

    h->is_streamed = 1;
    h->max_packet_size = 1472;

    is_output = !(flags & AVIO_FLAG_READ);

    s->ttl = 16;
    s->buffer_size = is_output ? UDP_TX_BUF_SIZE : UDP_MAX_PKT_SIZE;

    p = strchr(uri, '?');
    if (p) {
        if (av_find_info_tag(buf, sizeof(buf), "reuse", p)) {
            char *endptr = NULL;
            s->reuse_socket = strtol(buf, &endptr, 10);
            /* assume if no digits were found it is a request to enable it */
            if (buf == endptr)
                s->reuse_socket = 1;
            reuse_specified = 1;
        }
        if (av_find_info_tag(buf, sizeof(buf), "ttl", p)) {
            s->ttl = strtol(buf, NULL, 10);
        }
        if (av_find_info_tag(buf, sizeof(buf), "localport", p)) {
            s->local_port = strtol(buf, NULL, 10);
        }
        if (av_find_info_tag(buf, sizeof(buf), "pkt_size", p)) {
            h->max_packet_size = strtol(buf, NULL, 10);
        }
        if (av_find_info_tag(buf, sizeof(buf), "buffer_size", p)) {
            s->buffer_size = strtol(buf, NULL, 10);
        }
        if (av_find_info_tag(buf, sizeof(buf), "connect", p)) {
            s->is_connected = strtol(buf, NULL, 10);
        }
        if (av_find_info_tag(buf, sizeof(buf), "localaddr", p)) {
            av_strlcpy(localaddr, buf, sizeof(localaddr));
        }
        if (av_find_info_tag(buf, sizeof(buf), "sources", p)) {
            if (parse_source_list(buf, include_sources, &num_include_sources,
                                  FF_ARRAY_ELEMS(include_sources)))
                goto fail;
        }
        if (av_find_info_tag(buf, sizeof(buf), "block", p)) {
            if (parse_source_list(buf, exclude_sources, &num_exclude_sources,
                                  FF_ARRAY_ELEMS(exclude_sources)))
                goto fail;
        }
    }

    /* fill the dest addr */
    av_url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &port, NULL, 0, uri);

    /* XXX: fix av_url_split */
    if (hostname[0] == '\0' || hostname[0] == '?') {
        /* only accepts null hostname if input */
        if (!(flags & AVIO_FLAG_READ))
            goto fail;
    } else {
        if (ff_udp_set_remote_url(h, uri) < 0)
            goto fail;
    }

    if ((s->is_multicast || !s->local_port) && (h->flags & AVIO_FLAG_READ))
        s->local_port = port;
    udp_fd = udp_socket_create(s, &my_addr, &len, localaddr);
    if (udp_fd < 0)
        goto fail;

    /* Follow the requested reuse option, unless it's multicast in which
     * case enable reuse unless explicitly disabled.
     */
    if (s->reuse_socket || (s->is_multicast && !reuse_specified)) {
        s->reuse_socket = 1;
        if (setsockopt (udp_fd, SOL_SOCKET, SO_REUSEADDR, &(s->reuse_socket), sizeof(s->reuse_socket)) != 0)
            goto fail;
    }

    /* If multicast, try binding the multicast address first, to avoid
     * receiving UDP packets from other sources aimed at the same UDP
     * port. This fails on windows. This makes sending to the same address
     * using sendto() fail, so only do it if we're opened in read-only mode. */
    if (s->is_multicast && !(h->flags & AVIO_FLAG_WRITE)) {
        bind_ret = bind(udp_fd,(struct sockaddr *)&s->dest_addr, len);
    }
    /* bind to the local address if not multicast or if the multicast
     * bind failed */
    /* the bind is needed to give a port to the socket now */
    if (bind_ret < 0 && bind(udp_fd,(struct sockaddr *)&my_addr, len) < 0) {
        log_net_error(h, AV_LOG_ERROR, "bind failed");
        goto fail;
    }

    len = sizeof(my_addr);
    getsockname(udp_fd, (struct sockaddr *)&my_addr, &len);
    s->local_port = udp_port(&my_addr, len);

    if (s->is_multicast) {
        if (h->flags & AVIO_FLAG_WRITE) {
            /* output */
            if (udp_set_multicast_ttl(udp_fd, s->ttl, (struct sockaddr *)&s->dest_addr) < 0)
                goto fail;
        }
        if (h->flags & AVIO_FLAG_READ) {
            /* input */
            if (num_include_sources && num_exclude_sources) {
                av_log(h, AV_LOG_ERROR, "Simultaneously including and excluding multicast sources is not supported\n");
                goto fail;
            }
            if (num_include_sources) {
                if (udp_set_multicast_sources(udp_fd, (struct sockaddr *)&s->dest_addr, s->dest_addr_len, include_sources, num_include_sources, 1) < 0)
                    goto fail;
            } else {
                if (udp_join_multicast_group(udp_fd, (struct sockaddr *)&s->dest_addr) < 0)
                    goto fail;
            }
            if (num_exclude_sources) {
                if (udp_set_multicast_sources(udp_fd, (struct sockaddr *)&s->dest_addr, s->dest_addr_len, exclude_sources, num_exclude_sources, 0) < 0)
                    goto fail;
            }
        }
    }

    if (is_output) {
        /* limit the tx buf size to limit latency */
        tmp = s->buffer_size;
        if (setsockopt(udp_fd, SOL_SOCKET, SO_SNDBUF, &tmp, sizeof(tmp)) < 0) {
            log_net_error(h, AV_LOG_ERROR, "setsockopt(SO_SNDBUF)");
            goto fail;
        }
    } else {
        /* set udp recv buffer size to the largest possible udp packet size to
         * avoid losing data on OSes that set this too low by default. */
        tmp = s->buffer_size;
        if (setsockopt(udp_fd, SOL_SOCKET, SO_RCVBUF, &tmp, sizeof(tmp)) < 0) {
            log_net_error(h, AV_LOG_WARNING, "setsockopt(SO_RECVBUF)");
        }
        /* make the socket non-blocking */
        ff_socket_nonblock(udp_fd, 1);
    }
    if (s->is_connected) {
        if (connect(udp_fd, (struct sockaddr *) &s->dest_addr, s->dest_addr_len)) {
            log_net_error(h, AV_LOG_ERROR, "connect");
            goto fail;
        }
    }

    for (i = 0; i < num_include_sources; i++)
        av_freep(&include_sources[i]);
    for (i = 0; i < num_exclude_sources; i++)
        av_freep(&exclude_sources[i]);

    s->udp_fd = udp_fd;
    return 0;
 fail:
    if (udp_fd >= 0)
        closesocket(udp_fd);
    for (i = 0; i < num_include_sources; i++)
        av_freep(&include_sources[i]);
    for (i = 0; i < num_exclude_sources; i++)
        av_freep(&exclude_sources[i]);
    return AVERROR(EIO);
}