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/*
* UDP prototype streaming system
* Copyright (c) 2000 Gerard Lantau.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include "avformat.h"
typedef struct {
int udp_socket;
int max_payload_size; /* in bytes */
} UDPContext;
#define UDP_TX_BUF_SIZE 32768
/* put it in UDP context */
static struct sockaddr_in dest_addr;
/* return non zero if error */
static int udp_open(URLContext *h, const char *uri, int flags)
{
int local_port = 0;
struct sockaddr_in my_addr;
const char *p, *q;
char hostname[1024];
int port, udp_socket, tmp;
struct hostent *hp;
UDPContext *s;
h->is_streamed = 1;
if (!(flags & URL_WRONLY))
return -EIO;
/* fill the dest addr */
p = uri;
if (!strstart(p, "udp:", &p))
return -1;
q = strchr(p, ':');
if (!q)
return -1;
memcpy(hostname, p, q - p);
hostname[q - p] = '\0';
port = strtol(q+1, NULL, 10);
if (port <= 0)
return -1;
dest_addr.sin_family = AF_INET;
dest_addr.sin_port = htons(port);
if ((inet_aton(hostname, &dest_addr.sin_addr)) == 0) {
hp = gethostbyname(hostname);
if (!hp)
return -1;
memcpy ((char *) &dest_addr.sin_addr, hp->h_addr, hp->h_length);
}
udp_socket = socket(PF_INET, SOCK_DGRAM, 0);
if (udp_socket < 0)
return -1;
my_addr.sin_family = AF_INET;
my_addr.sin_port = htons(local_port);
my_addr.sin_addr.s_addr = htonl (INADDR_ANY);
/* the bind is needed to give a port to the socket now */
if (bind(udp_socket,(struct sockaddr *)&my_addr, sizeof(my_addr)) < 0)
goto fail;
/* limit the tx buf size to limit latency */
tmp = UDP_TX_BUF_SIZE;
if (setsockopt(udp_socket, SOL_SOCKET, SO_SNDBUF, &tmp, sizeof(tmp)) < 0) {
perror("setsockopt sndbuf");
goto fail;
}
s = malloc(sizeof(UDPContext));
if (!s)
return -ENOMEM;
h->priv_data = s;
s->udp_socket = udp_socket;
h->packet_size = 1500;
return 0;
fail:
return -EIO;
}
int udp_close(URLContext *h)
{
UDPContext *s = h->priv_data;
close(s->udp_socket);
return 0;
}
int udp_write(URLContext *h, UINT8 *buf, int size)
{
UDPContext *s = h->priv_data;
int ret, len, size1;
/* primitive way to avoid big packets */
size1 = size;
while (size > 0) {
len = size;
if (len > h->packet_size)
len = h->packet_size;
ret = sendto (s->udp_socket, buf, len, 0,
(struct sockaddr *) &dest_addr,
sizeof (dest_addr));
if (ret < 0)
perror("sendto");
buf += len;
size -= len;
}
return size1 - size;
}
URLProtocol udp_protocol = {
"udp",
udp_open,
NULL, /* read */
udp_write,
NULL, /* seek */
udp_close,
};
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