/*
* RTP network protocol
* Copyright (c) 2002 Fabrice Bellard
*
* This file is part of FFmpeg.
*
* FFmpeg 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 2.1 of the License, or (at your option) any later version.
*
* FFmpeg 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 FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* RTP protocol
*/
#include "libavutil/parseutils.h"
#include "libavutil/avstring.h"
#include "avformat.h"
#include "avio_internal.h"
#include "rtpdec.h"
#include "url.h"
#include <stdarg.h>
#include "internal.h"
#include "network.h"
#include "os_support.h"
#include <fcntl.h>
#if HAVE_POLL_H
#include <sys/poll.h>
#endif
typedef struct RTPContext {
URLContext *rtp_hd, *rtcp_hd;
int rtp_fd, rtcp_fd;
} RTPContext;
/**
* 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.
*
* @param h media file context
* @param uri of the remote server
* @return zero if no error.
*/
int ff_rtp_set_remote_url(URLContext *h, const char *uri)
{
RTPContext *s = h->priv_data;
char hostname[256];
int port;
char buf[1024];
char path[1024];
av_url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &port,
path, sizeof(path), uri);
ff_url_join(buf, sizeof(buf), "udp", NULL, hostname, port, "%s", path);
ff_udp_set_remote_url(s->rtp_hd, buf);
ff_url_join(buf, sizeof(buf), "udp", NULL, hostname, port + 1, "%s", path);
ff_udp_set_remote_url(s->rtcp_hd, buf);
return 0;
}
/**
* add option to url of the form:
* "http://host:port/path?option1=val1&option2=val2...
*/
static av_printf_format(3, 4) void url_add_option(char *buf, int buf_size, const char *fmt, ...)
{
char buf1[1024];
va_list ap;
va_start(ap, fmt);
if (strchr(buf, '?'))
av_strlcat(buf, "&", buf_size);
else
av_strlcat(buf, "?", buf_size);
vsnprintf(buf1, sizeof(buf1), fmt, ap);
av_strlcat(buf, buf1, buf_size);
va_end(ap);
}
static void build_udp_url(char *buf, int buf_size,
const char *hostname, int port,
int local_port, int ttl,
int max_packet_size, int connect)
{
ff_url_join(buf, buf_size, "udp", NULL, hostname, port, NULL);
if (local_port >= 0)
url_add_option(buf, buf_size, "localport=%d", local_port);
if (ttl >= 0)
url_add_option(buf, buf_size, "ttl=%d", ttl);
if (max_packet_size >=0)
url_add_option(buf, buf_size, "pkt_size=%d", max_packet_size);
if (connect)
url_add_option(buf, buf_size, "connect=1");
url_add_option(buf, buf_size, "fifo_size=0");
}
/**
* url syntax: rtp://host:port[?option=val...]
* option: 'ttl=n' : set the ttl value (for multicast only)
* 'rtcpport=n' : set the remote rtcp port to n
* 'localrtpport=n' : set the local rtp port to n
* 'localrtcpport=n' : set the local rtcp port to n
* 'pkt_size=n' : set max packet size
* 'connect=0/1' : do a connect() on the UDP socket
* deprecated option:
* 'localport=n' : set the local port to n
*
* if rtcpport isn't set the rtcp port will be the rtp port + 1
* if local rtp port isn't set any available port will be used for the local
* rtp and rtcp ports
* if the local rtcp port is not set it will be the local rtp port + 1
*/
static int rtp_open(URLContext *h, const char *uri, int flags)
{
RTPContext *s = h->priv_data;
int rtp_port, rtcp_port,
ttl, connect,
local_rtp_port, local_rtcp_port, max_packet_size;
char hostname[256];
char buf[1024];
char path[1024];
const char *p;
av_url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &rtp_port,
path, sizeof(path), uri);
/* extract parameters */
ttl = -1;
rtcp_port = rtp_port+1;
local_rtp_port = -1;
local_rtcp_port = -1;
max_packet_size = -1;
connect = 0;
p = strchr(uri, '?');
if (p) {
if (av_find_info_tag(buf, sizeof(buf), "ttl", p)) {
ttl = strtol(buf, NULL, 10);
}
if (av_find_info_tag(buf, sizeof(buf), "rtcpport", p)) {
rtcp_port = strtol(buf, NULL, 10);
}
if (av_find_info_tag(buf, sizeof(buf), "localport", p)) {
local_rtp_port = strtol(buf, NULL, 10);
}
if (av_find_info_tag(buf, sizeof(buf), "localrtpport", p)) {
local_rtp_port = strtol(buf, NULL, 10);
}
if (av_find_info_tag(buf, sizeof(buf), "localrtcpport", p)) {
local_rtcp_port = strtol(buf, NULL, 10);
}
if (av_find_info_tag(buf, sizeof(buf), "pkt_size", p)) {
max_packet_size = strtol(buf, NULL, 10);
}
if (av_find_info_tag(buf, sizeof(buf), "connect", p)) {
connect = strtol(buf, NULL, 10);
}
}
build_udp_url(buf, sizeof(buf),
hostname, rtp_port, local_rtp_port, ttl, max_packet_size,
connect);
if (ffurl_open(&s->rtp_hd, buf, flags, &h->interrupt_callback, NULL) < 0)
goto fail;
if (local_rtp_port>=0 && local_rtcp_port<0)
local_rtcp_port = ff_udp_get_local_port(s->rtp_hd) + 1;
build_udp_url(buf, sizeof(buf),
hostname, rtcp_port, local_rtcp_port, ttl, max_packet_size,
connect);
if (ffurl_open(&s->rtcp_hd, buf, flags, &h->interrupt_callback, NULL) < 0)
goto fail;
/* just to ease handle access. XXX: need to suppress direct handle
access */
s->rtp_fd = ffurl_get_file_handle(s->rtp_hd);
s->rtcp_fd = ffurl_get_file_handle(s->rtcp_hd);
h->max_packet_size = s->rtp_hd->max_packet_size;
h->is_streamed = 1;
return 0;
fail:
if (s->rtp_hd)
ffurl_close(s->rtp_hd);
if (s->rtcp_hd)
ffurl_close(s->rtcp_hd);
return AVERROR(EIO);
}
static int rtp_read(URLContext *h, uint8_t *buf, int size)
{
RTPContext *s = h->priv_data;
struct sockaddr_storage from;
socklen_t from_len;
int len, n;
struct pollfd p[2] = {{s->rtp_fd, POLLIN, 0}, {s->rtcp_fd, POLLIN, 0}};
for(;;) {
if (ff_check_interrupt(&h->interrupt_callback))
return AVERROR_EXIT;
/* build fdset to listen to RTP and RTCP packets */
n = poll(p, 2, 100);
if (n > 0) {
/* first try RTCP */
if (p[1].revents & POLLIN) {
from_len = sizeof(from);
len = recvfrom (s->rtcp_fd, buf, size, 0,
(struct sockaddr *)&from, &from_len);
if (len < 0) {
if (ff_neterrno() == AVERROR(EAGAIN) ||
ff_neterrno() == AVERROR(EINTR))
continue;
return AVERROR(EIO);
}
break;
}
/* then RTP */
if (p[0].revents & POLLIN) {
from_len = sizeof(from);
len = recvfrom (s->rtp_fd, buf, size, 0,
(struct sockaddr *)&from, &from_len);
if (len < 0) {
if (ff_neterrno() == AVERROR(EAGAIN) ||
ff_neterrno() == AVERROR(EINTR))
continue;
return AVERROR(EIO);
}
break;
}
} else if (n < 0) {
if (ff_neterrno() == AVERROR(EINTR))
continue;
return AVERROR(EIO);
}
}
return len;
}
static int rtp_write(URLContext *h, const uint8_t *buf, int size)
{
RTPContext *s = h->priv_data;
int ret;
URLContext *hd;
if (RTP_PT_IS_RTCP(buf[1])) {
/* RTCP payload type */
hd = s->rtcp_hd;
} else {
/* RTP payload type */
hd = s->rtp_hd;
}
ret = ffurl_write(hd, buf, size);
return ret;
}
static int rtp_close(URLContext *h)
{
RTPContext *s = h->priv_data;
ffurl_close(s->rtp_hd);
ffurl_close(s->rtcp_hd);
return 0;
}
/**
* Return the local rtp port used by the RTP connection
* @param h media file context
* @return the local port number
*/
int ff_rtp_get_local_rtp_port(URLContext *h)
{
RTPContext *s = h->priv_data;
return ff_udp_get_local_port(s->rtp_hd);
}
/**
* Return the local rtcp port used by the RTP connection
* @param h media file context
* @return the local port number
*/
int ff_rtp_get_local_rtcp_port(URLContext *h)
{
RTPContext *s = h->priv_data;
return ff_udp_get_local_port(s->rtcp_hd);
}
static int rtp_get_file_handle(URLContext *h)
{
RTPContext *s = h->priv_data;
return s->rtp_fd;
}
static int rtp_get_multi_file_handle(URLContext *h, int **handles,
int *numhandles)
{
RTPContext *s = h->priv_data;
int *hs = *handles = av_malloc(sizeof(**handles) * 2);
if (!hs)
return AVERROR(ENOMEM);
hs[0] = s->rtp_fd;
hs[1] = s->rtcp_fd;
*numhandles = 2;
return 0;
}
URLProtocol ff_rtp_protocol = {
.name = "rtp",
.url_open = rtp_open,
.url_read = rtp_read,
.url_write = rtp_write,
.url_close = rtp_close,
.url_get_file_handle = rtp_get_file_handle,
.url_get_multi_file_handle = rtp_get_multi_file_handle,
.priv_data_size = sizeof(RTPContext),
.flags = URL_PROTOCOL_FLAG_NETWORK,
};