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|
/*
* UDP prototype streaming system
* Copyright (c) 2000, 2001, 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 libavformat/udp.c
* UDP protocol
*/
#define _BSD_SOURCE /* Needed for using struct ip_mreq with recent glibc */
#include "avformat.h"
#include <unistd.h>
#include "network.h"
#include "os_support.h"
#if HAVE_SYS_SELECT_H
#include <sys/select.h>
#endif
#include <sys/time.h>
#ifndef IPV6_ADD_MEMBERSHIP
#define IPV6_ADD_MEMBERSHIP IPV6_JOIN_GROUP
#define IPV6_DROP_MEMBERSHIP IPV6_LEAVE_GROUP
#endif
#ifndef IN_MULTICAST
#define IN_MULTICAST(a) ((((uint32_t)(a)) & 0xf0000000) == 0xe0000000)
#endif
#ifndef IN6_IS_ADDR_MULTICAST
#define IN6_IS_ADDR_MULTICAST(a) (((uint8_t *) (a))[0] == 0xff)
#endif
typedef struct {
int udp_fd;
int ttl;
int buffer_size;
int is_multicast;
int local_port;
int reuse_socket;
struct sockaddr_storage dest_addr;
int dest_addr_len;
} UDPContext;
#define UDP_TX_BUF_SIZE 32768
#define UDP_MAX_PKT_SIZE 65536
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) {
av_log(NULL, AV_LOG_ERROR, "setsockopt(IP_MULTICAST_TTL): %s\n", strerror(errno));
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) {
av_log(NULL, AV_LOG_ERROR, "setsockopt(IPV6_MULTICAST_HOPS): %s\n", strerror(errno));
return -1;
}
}
#endif
return 0;
}
static int udp_join_multicast_group(int sockfd, struct sockaddr *addr) {
#ifdef IP_ADD_MEMBERSHIP
if (addr->sa_family == AF_INET) {
struct ip_mreq mreq;
mreq.imr_multiaddr.s_addr = ((struct sockaddr_in *)addr)->sin_addr.s_addr;
mreq.imr_interface.s_addr= INADDR_ANY;
if (setsockopt(sockfd, IPPROTO_IP, IP_ADD_MEMBERSHIP, (const void *)&mreq, sizeof(mreq)) < 0) {
av_log(NULL, AV_LOG_ERROR, "setsockopt(IP_ADD_MEMBERSHIP): %s\n", strerror(errno));
return -1;
}
}
#endif
#if HAVE_STRUCT_IPV6_MREQ
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_ADD_MEMBERSHIP, &mreq6, sizeof(mreq6)) < 0) {
av_log(NULL, AV_LOG_ERROR, "setsockopt(IPV6_ADD_MEMBERSHIP): %s\n", strerror(errno));
return -1;
}
}
#endif
return 0;
}
static int udp_leave_multicast_group(int sockfd, struct sockaddr *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;
mreq.imr_interface.s_addr= INADDR_ANY;
if (setsockopt(sockfd, IPPROTO_IP, IP_DROP_MEMBERSHIP, (const void *)&mreq, sizeof(mreq)) < 0) {
av_log(NULL, AV_LOG_ERROR, "setsockopt(IP_DROP_MEMBERSHIP): %s\n", strerror(errno));
return -1;
}
}
#endif
#if HAVE_STRUCT_IPV6_MREQ
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) {
av_log(NULL, AV_LOG_ERROR, "setsockopt(IPV6_DROP_MEMBERSHIP): %s\n", strerror(errno));
return -1;
}
}
#endif
return 0;
}
static struct addrinfo* udp_resolve_host(const char *hostname, int port, int type, int family, int flags) {
struct addrinfo hints, *res = 0;
int error;
char sport[16];
const char *node = 0, *service = "0";
if (port > 0) {
snprintf(sport, sizeof(sport), "%d", port);
service = sport;
}
if ((hostname) && (hostname[0] != '\0') && (hostname[0] != '?')) {
node = hostname;
}
memset(&hints, 0, sizeof(hints));
hints.ai_socktype = type;
hints.ai_family = family;
hints.ai_flags = flags;
if ((error = getaddrinfo(node, service, &hints, &res))) {
av_log(NULL, AV_LOG_ERROR, "udp_resolve_host: %s\n", gai_strerror(error));
}
return res;
}
static int udp_set_url(struct sockaddr_storage *addr, const char *hostname, int port) {
struct addrinfo *res0;
int addr_len;
res0 = udp_resolve_host(hostname, port, SOCK_DGRAM, AF_UNSPEC, 0);
if (res0 == 0) return AVERROR(EIO);
memcpy(addr, res0->ai_addr, res0->ai_addrlen);
addr_len = res0->ai_addrlen;
freeaddrinfo(res0);
return addr_len;
}
static int is_multicast_address(struct sockaddr_storage *addr)
{
if (addr->ss_family == AF_INET) {
return IN_MULTICAST(ntohl(((struct sockaddr_in *)addr)->sin_addr.s_addr));
}
#if HAVE_STRUCT_SOCKADDR_IN6
if (addr->ss_family == AF_INET6) {
return IN6_IS_ADDR_MULTICAST(&((struct sockaddr_in6 *)addr)->sin6_addr);
}
#endif
return 0;
}
static int udp_socket_create(UDPContext *s, struct sockaddr_storage *addr, int *addr_len)
{
int udp_fd = -1;
struct addrinfo *res0 = NULL, *res = NULL;
int family = AF_UNSPEC;
if (((struct sockaddr *) &s->dest_addr)->sa_family)
family = ((struct sockaddr *) &s->dest_addr)->sa_family;
res0 = udp_resolve_host(0, s->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 > 0) break;
av_log(NULL, AV_LOG_ERROR, "socket: %s\n", strerror(errno));
}
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;
}
static int udp_port(struct sockaddr_storage *addr, int addr_len)
{
char sbuf[sizeof(int)*3+1];
if (getnameinfo((struct sockaddr *)addr, addr_len, NULL, 0, sbuf, sizeof(sbuf), NI_NUMERICSERV) != 0) {
av_log(NULL, AV_LOG_ERROR, "getnameinfo: %s\n", strerror(errno));
return -1;
}
return strtol(sbuf, NULL, 10);
}
/**
* 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
*
* @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, 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 = is_multicast_address(&s->dest_addr);
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
*/
#if (LIBAVFORMAT_VERSION_MAJOR >= 53)
static
#endif
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)
{
char hostname[1024];
int port, udp_fd = -1, tmp, bind_ret = -1;
UDPContext *s = NULL;
int is_output;
const char *p;
char buf[256];
struct sockaddr_storage my_addr;
int len;
h->is_streamed = 1;
h->max_packet_size = 1472;
is_output = (flags & URL_WRONLY);
if(!ff_network_init())
return AVERROR(EIO);
s = av_mallocz(sizeof(UDPContext));
if (!s)
return AVERROR(ENOMEM);
h->priv_data = s;
s->ttl = 16;
s->buffer_size = is_output ? UDP_TX_BUF_SIZE : UDP_MAX_PKT_SIZE;
p = strchr(uri, '?');
if (p) {
s->reuse_socket = find_info_tag(buf, sizeof(buf), "reuse", 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);
}
if (find_info_tag(buf, sizeof(buf), "buffer_size", p)) {
s->buffer_size = strtol(buf, NULL, 10);
}
}
/* fill the dest addr */
url_split(NULL, 0, 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 (flags & URL_WRONLY)
goto fail;
} else {
udp_set_remote_url(h, uri);
}
if (s->is_multicast && !(h->flags & URL_WRONLY))
s->local_port = port;
udp_fd = udp_socket_create(s, &my_addr, &len);
if (udp_fd < 0)
goto fail;
if (s->reuse_socket)
if (setsockopt (udp_fd, SOL_SOCKET, SO_REUSEADDR, &(s->reuse_socket), sizeof(s->reuse_socket)) != 0)
goto fail;
/* the bind is needed to give a port to the socket now */
/* if multicast, try the multicast address bind first */
if (s->is_multicast && !(h->flags & URL_WRONLY)) {
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 */
if (bind_ret < 0 && bind(udp_fd,(struct sockaddr *)&my_addr, len) < 0)
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 & URL_WRONLY) {
/* output */
if (udp_set_multicast_ttl(udp_fd, s->ttl, (struct sockaddr *)&s->dest_addr) < 0)
goto fail;
} else {
/* input */
if (udp_join_multicast_group(udp_fd, (struct sockaddr *)&s->dest_addr) < 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) {
av_log(NULL, AV_LOG_ERROR, "setsockopt(SO_SNDBUF): %s\n", strerror(errno));
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) {
av_log(NULL, AV_LOG_WARNING, "setsockopt(SO_RECVBUF): %s\n", strerror(errno));
}
/* make the socket non-blocking */
ff_socket_nonblock(udp_fd, 1);
}
s->udp_fd = udp_fd;
return 0;
fail:
if (udp_fd >= 0)
closesocket(udp_fd);
av_free(s);
return AVERROR(EIO);
}
static int udp_read(URLContext *h, uint8_t *buf, int size)
{
UDPContext *s = h->priv_data;
int len;
fd_set rfds;
int ret;
struct timeval tv;
for(;;) {
if (url_interrupt_cb())
return AVERROR(EINTR);
FD_ZERO(&rfds);
FD_SET(s->udp_fd, &rfds);
tv.tv_sec = 0;
tv.tv_usec = 100 * 1000;
ret = select(s->udp_fd + 1, &rfds, NULL, NULL, &tv);
if (ret < 0)
return AVERROR(EIO);
if (!(ret > 0 && FD_ISSET(s->udp_fd, &rfds)))
continue;
len = recv(s->udp_fd, buf, size, 0);
if (len < 0) {
if (ff_neterrno() != FF_NETERROR(EAGAIN) &&
ff_neterrno() != FF_NETERROR(EINTR))
return AVERROR(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,
s->dest_addr_len);
if (ret < 0) {
if (ff_neterrno() != FF_NETERROR(EINTR) &&
ff_neterrno() != FF_NETERROR(EAGAIN))
return AVERROR(EIO);
} else {
break;
}
}
return size;
}
static int udp_close(URLContext *h)
{
UDPContext *s = h->priv_data;
if (s->is_multicast && !(h->flags & URL_WRONLY))
udp_leave_multicast_group(s->udp_fd, (struct sockaddr *)&s->dest_addr);
closesocket(s->udp_fd);
ff_network_close();
av_free(s);
return 0;
}
URLProtocol udp_protocol = {
"udp",
udp_open,
udp_read,
udp_write,
NULL, /* seek */
udp_close,
.url_get_file_handle = udp_get_file_handle,
};
|