ffmpeg/libavformat/udp.c

683 lines
23 KiB
C

/*
* UDP prototype streaming system
* Copyright (c) 2000, 2001, 2002 Fabrice Bellard
*
* This file is part of Libav.
*
* Libav 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.
*
* Libav 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* UDP protocol
*/
#define _BSD_SOURCE /* Needed for using struct ip_mreq with recent glibc */
#include "avformat.h"
#include "avio_internal.h"
#include "libavutil/parseutils.h"
#include "libavutil/avstring.h"
#include "libavutil/opt.h"
#include "internal.h"
#include "network.h"
#include "os_support.h"
#include "url.h"
#ifndef IPV6_ADD_MEMBERSHIP
#define IPV6_ADD_MEMBERSHIP IPV6_JOIN_GROUP
#define IPV6_DROP_MEMBERSHIP IPV6_LEAVE_GROUP
#endif
typedef struct UDPContext {
const AVClass *class;
int udp_fd;
int ttl;
int buffer_size;
int pkt_size;
int is_multicast;
int local_port;
int reuse_socket;
struct sockaddr_storage dest_addr;
int dest_addr_len;
int is_connected;
char *localaddr;
char *sources;
char *block;
} UDPContext;
#define UDP_TX_BUF_SIZE 32768
#define UDP_MAX_PKT_SIZE 65536
#define OFFSET(x) offsetof(UDPContext, x)
#define D AV_OPT_FLAG_DECODING_PARAM
#define E AV_OPT_FLAG_ENCODING_PARAM
static const AVOption options[] = {
{ "ttl", "Time to live (in milliseconds, multicast only)", OFFSET(ttl), AV_OPT_TYPE_INT, { .i64 = 16 }, 0, INT_MAX, .flags = D|E },
{ "buffer_size", "System data size (in bytes)", OFFSET(buffer_size), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, INT_MAX, .flags = D|E },
{ "local_port", "Local port", OFFSET(local_port), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, INT_MAX, .flags = D|E },
{ "reuse_socket", "Reuse socket", OFFSET(reuse_socket), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, 1, .flags = D|E },
{ "connect", "Connect socket", OFFSET(is_connected), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, .flags = D|E },
{ "pkt_size", "Maximum packet size", OFFSET(pkt_size), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, INT_MAX, .flags = D|E },
{ "localaddr", "Local address", OFFSET(localaddr), AV_OPT_TYPE_STRING, { .str = NULL }, .flags = D|E },
{ "sources", "Source list", OFFSET(sources), AV_OPT_TYPE_STRING, { .str = NULL }, .flags = D|E },
{ "block", "Block list", OFFSET(block), AV_OPT_TYPE_STRING, { .str = NULL }, .flags = D|E },
{ NULL }
};
static const AVClass udp_class = {
.class_name = "udp",
.item_name = av_default_item_name,
.option = options,
.version = LIBAVUTIL_VERSION_INT,
};
static void log_net_error(void *ctx, int level, const char* prefix)
{
char errbuf[100];
av_strerror(ff_neterrno(), errbuf, sizeof(errbuf));
av_log(ctx, level, "%s: %s\n", prefix, errbuf);
}
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;
}
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) {
log_net_error(NULL, AV_LOG_ERROR, "setsockopt(IP_ADD_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_ADD_MEMBERSHIP, &mreq6, sizeof(mreq6)) < 0) {
log_net_error(NULL, AV_LOG_ERROR, "setsockopt(IPV6_ADD_MEMBERSHIP)");
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) {
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;
}
static struct addrinfo* udp_resolve_host(const char *hostname, int port,
int type, int family, int flags)
{
struct addrinfo hints = { 0 }, *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;
}
hints.ai_socktype = type;
hints.ai_family = family;
hints.ai_flags = flags;
if ((error = getaddrinfo(node, service, &hints, &res))) {
res = NULL;
av_log(NULL, AV_LOG_ERROR, "udp_resolve_host: %s\n", gai_strerror(error));
}
return res;
}
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;
}
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 udp_socket_create(UDPContext *s, 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;
if (((struct sockaddr *) &s->dest_addr)->sa_family)
family = ((struct sockaddr *) &s->dest_addr)->sa_family;
res0 = udp_resolve_host((localaddr && localaddr[0]) ? localaddr : NULL, s->local_port,
SOCK_DGRAM, family, AI_PASSIVE);
if (res0 == 0)
goto fail;
for (res = res0; res; res=res->ai_next) {
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;
}
static int udp_port(struct sockaddr_storage *addr, int addr_len)
{
char sbuf[sizeof(int)*3+1];
int error;
if ((error = getnameinfo((struct sockaddr *)addr, addr_len, NULL, 0, sbuf, sizeof(sbuf), NI_NUMERICSERV)) != 0) {
av_log(NULL, AV_LOG_ERROR, "getnameinfo: %s\n", gai_strerror(error));
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 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;
}
/**
* Return the local port used by the UDP connection
* @param h media file context
* @return the local port number
*/
int ff_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
*/
static int udp_get_file_handle(URLContext *h)
{
UDPContext *s = h->priv_data;
return s->udp_fd;
}
static int parse_source_list(char *buf, char **sources, int *num_sources,
int max_sources)
{
char *source_start;
source_start = buf;
while (1) {
char *next = strchr(source_start, ',');
if (next)
*next = '\0';
sources[*num_sources] = av_strdup(source_start);
if (!sources[*num_sources])
return AVERROR(ENOMEM);
source_start = next + 1;
(*num_sources)++;
if (*num_sources >= max_sources || !next)
break;
}
return 0;
}
/* put it in UDP context */
/* 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 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);
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)
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), "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;
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;
/* 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 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);
}
static int udp_read(URLContext *h, uint8_t *buf, int size)
{
UDPContext *s = h->priv_data;
int ret;
if (!(h->flags & AVIO_FLAG_NONBLOCK)) {
ret = ff_network_wait_fd(s->udp_fd, 0);
if (ret < 0)
return ret;
}
ret = recv(s->udp_fd, buf, size, 0);
return ret < 0 ? ff_neterrno() : ret;
}
static int udp_write(URLContext *h, const uint8_t *buf, int size)
{
UDPContext *s = h->priv_data;
int ret;
if (!(h->flags & AVIO_FLAG_NONBLOCK)) {
ret = ff_network_wait_fd(s->udp_fd, 1);
if (ret < 0)
return ret;
}
if (!s->is_connected) {
ret = sendto (s->udp_fd, buf, size, 0,
(struct sockaddr *) &s->dest_addr,
s->dest_addr_len);
} else
ret = send(s->udp_fd, buf, size, 0);
return ret < 0 ? ff_neterrno() : ret;
}
static int udp_close(URLContext *h)
{
UDPContext *s = h->priv_data;
if (s->is_multicast && (h->flags & AVIO_FLAG_READ))
udp_leave_multicast_group(s->udp_fd, (struct sockaddr *)&s->dest_addr);
closesocket(s->udp_fd);
return 0;
}
URLProtocol ff_udp_protocol = {
.name = "udp",
.url_open = udp_open,
.url_read = udp_read,
.url_write = udp_write,
.url_close = udp_close,
.url_get_file_handle = udp_get_file_handle,
.priv_data_size = sizeof(UDPContext),
.flags = URL_PROTOCOL_FLAG_NETWORK,
.priv_data_class = &udp_class,
};