/* * UDP prototype streaming system * Copyright (c) 2000, 2001, 2002 Fabrice Bellard. * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */#include "avformat.h"#include <unistd.h>#include <sys/types.h>#include <sys/socket.h>#include <netinet/in.h>#ifndef __BEOS__# include <arpa/inet.h>#else# include "barpainet.h"#endif#include <netdb.h>typedef struct {    int udp_fd;    int ttl;    int is_multicast;    int local_port;    struct ip_mreq mreq;    struct sockaddr_in dest_addr;} UDPContext;#define UDP_TX_BUF_SIZE 32768/** * 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: 'multicast=1' : enable multicast  *         'ttl=n'       : set the ttl value (for multicast only) *         'localport=n' : set the local port *         'pkt_size=n'  : set max packet size * * @param s1 media file context * @param uri of the remote server * @return zero if no error. */int udp_set_remote_url(URLContext *h, const char *uri){    UDPContext *s = h->priv_data;    char hostname[256];    int port;        url_split(NULL, 0, hostname, sizeof(hostname), &port, NULL, 0, uri);    /* set the destination address */    if (resolve_host(&s->dest_addr.sin_addr, hostname) < 0)        return -EIO;    s->dest_addr.sin_family = AF_INET;    s->dest_addr.sin_port = htons(port);    return 0;}/** * Return the local port used by the UDP connexion * @param s1 media file context * @return the local port number */int udp_get_local_port(URLContext *h){    UDPContext *s = h->priv_data;    return s->local_port;}/** * Return the udp file handle for select() usage to wait for several RTP * streams at the same time. * @param h media file context */int udp_get_file_handle(URLContext *h){    UDPContext *s = h->priv_data;    return s->udp_fd;}/* put it in UDP context *//* return non zero if error */static int udp_open(URLContext *h, const char *uri, int flags){    struct sockaddr_in my_addr, my_addr1;    char hostname[1024];    int port, udp_fd = -1, tmp;    UDPContext *s = NULL;    int is_output, len;    const char *p;    char buf[256];    h->is_streamed = 1;    h->max_packet_size = 1472;    is_output = (flags & URL_WRONLY);        s = av_malloc(sizeof(UDPContext));    if (!s)        return -ENOMEM;    h->priv_data = s;    s->ttl = 16;    s->is_multicast = 0;    s->local_port = 0;    p = strchr(uri, '?');    if (p) {        s->is_multicast = find_info_tag(buf, sizeof(buf), "multicast", p);        if (find_info_tag(buf, sizeof(buf), "ttl", p)) {            s->ttl = strtol(buf, NULL, 10);        }        if (find_info_tag(buf, sizeof(buf), "localport", p)) {            s->local_port = strtol(buf, NULL, 10);        }        if (find_info_tag(buf, sizeof(buf), "pkt_size", p)) {            h->max_packet_size = strtol(buf, NULL, 10);        }    }    /* fill the dest addr */    url_split(NULL, 0, hostname, sizeof(hostname), &port, NULL, 0, uri);        /* XXX: fix url_split */    if (hostname[0] == '\0' || hostname[0] == '?') {        /* only accepts null hostname if input */        if (s->is_multicast || (flags & URL_WRONLY))            goto fail;    } else {        udp_set_remote_url(h, uri);    }    udp_fd = socket(PF_INET, SOCK_DGRAM, 0);    if (udp_fd < 0)        goto fail;    my_addr.sin_family = AF_INET;    my_addr.sin_addr.s_addr = htonl (INADDR_ANY);    if (s->is_multicast && !(h->flags & URL_WRONLY)) {        /* special case: the bind must be done on the multicast address port */        my_addr.sin_port = s->dest_addr.sin_port;    } else {        my_addr.sin_port = htons(s->local_port);    }    /* the bind is needed to give a port to the socket now */    if (bind(udp_fd,(struct sockaddr *)&my_addr, sizeof(my_addr)) < 0)         goto fail;    len = sizeof(my_addr1);    getsockname(udp_fd, (struct sockaddr *)&my_addr1, &len);    s->local_port = ntohs(my_addr1.sin_port);#ifndef CONFIG_BEOS_NETSERVER    if (s->is_multicast) {        if (h->flags & URL_WRONLY) {            /* output */            if (setsockopt(udp_fd, IPPROTO_IP, IP_MULTICAST_TTL,                            &s->ttl, sizeof(s->ttl)) < 0) {                perror("IP_MULTICAST_TTL");                goto fail;            }        } else {            /* input */            memset(&s->mreq, 0, sizeof(s->mreq));            s->mreq.imr_multiaddr = s->dest_addr.sin_addr;            s->mreq.imr_interface.s_addr = htonl (INADDR_ANY);            if (setsockopt(udp_fd, IPPROTO_IP, IP_ADD_MEMBERSHIP,                            &s->mreq, sizeof(s->mreq)) < 0) {                perror("rtp: IP_ADD_MEMBERSHIP");                goto fail;            }        }    }#endif    if (is_output) {        /* limit the tx buf size to limit latency */        tmp = UDP_TX_BUF_SIZE;        if (setsockopt(udp_fd, SOL_SOCKET, SO_SNDBUF, &tmp, sizeof(tmp)) < 0) {            perror("setsockopt sndbuf");            goto fail;        }    }    s->udp_fd = udp_fd;    return 0; fail:    if (udp_fd >= 0)#ifdef CONFIG_BEOS_NETSERVER        closesocket(udp_fd);#else        close(udp_fd);#endif    av_free(s);    return -EIO;}static int udp_read(URLContext *h, uint8_t *buf, int size){    UDPContext *s = h->priv_data;    struct sockaddr_in from;    int from_len, len;    for(;;) {        from_len = sizeof(from);        len = recvfrom (s->udp_fd, buf, size, 0,                        (struct sockaddr *)&from, &from_len);        if (len < 0) {            if (errno != EAGAIN && errno != EINTR)                return -EIO;        } else {            break;        }    }    return len;}static int udp_write(URLContext *h, uint8_t *buf, int size){    UDPContext *s = h->priv_data;    int ret;    for(;;) {        ret = sendto (s->udp_fd, buf, size, 0,                       (struct sockaddr *) &s->dest_addr,                      sizeof (s->dest_addr));        if (ret < 0) {            if (errno != EINTR && errno != EAGAIN)                return -EIO;        } else {            break;        }    }    return size;}static int udp_close(URLContext *h){    UDPContext *s = h->priv_data;#ifndef CONFIG_BEOS_NETSERVER    if (s->is_multicast && !(h->flags & URL_WRONLY)) {        if (setsockopt(s->udp_fd, IPPROTO_IP, IP_DROP_MEMBERSHIP,                        &s->mreq, sizeof(s->mreq)) < 0) {            perror("IP_DROP_MEMBERSHIP");        }    }    close(s->udp_fd);#else    closesocket(s->udp_fd);#endif    av_free(s);    return 0;}URLProtocol udp_protocol = {    "udp",    udp_open,    udp_read,    udp_write,    NULL, /* seek */    udp_close,};