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ffmpeg/libavformat/udp.c
Nicolas George 463705bd1c udp: fix non-blocking and interrupt handling. 
In non-blocking mode, lowest-level read protocols are
supposed block only for a short amount of time to let
retry_transfer_wrapper() check for interrupts.

Also, checking the interrupt_callback in the receiving thread is
wrong, as interrupt_callback is not guaranteed to be thread-safe
and the job is already done by retry_transfer_wrapper(). The error
code was also incorrect.

Bug reported by Andrey Utkin.
2012-03-17 14:43:37 +01:00

694 lines
22 KiB
C
Raw Blame History

/*
* 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
* 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/fifo.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/avstring.h"
#include <unistd.h>
#include "internal.h"
#include "network.h"
#include "os_support.h"
#include "url.h"
#if HAVE_PTHREADS
#include <pthread.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
#define UDP_TX_BUF_SIZE 32768
#define UDP_MAX_PKT_SIZE 65536
typedef struct {
int udp_fd;
int ttl;
int buffer_size;
int is_multicast;
int local_port;
int reuse_socket;
int overrun_nonfatal;
struct sockaddr_storage dest_addr;
int dest_addr_len;
int is_connected;
/* Circular Buffer variables for use in UDP receive code */
int circular_buffer_size;
AVFifoBuffer *fifo;
int circular_buffer_error;
#if HAVE_PTHREADS
pthread_t circular_buffer_thread;
pthread_mutex_t mutex;
pthread_cond_t cond;
int thread_started;
volatile int exit_thread;
#endif
uint8_t tmp[UDP_MAX_PKT_SIZE+4];
int remaining_in_dg;
} UDPContext;
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 && 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) {
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 && 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) {
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))) {
res = NULL;
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 udp_socket_create(UDPContext *s, struct sockaddr_storage *addr,
int *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[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 = 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
* 'overrun_nonfatal=1': survive in case of circular buffer overrun
*
* @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;
av_log(h, AV_LOG_ERROR, "connect: %s\n", strerror(errno));
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;
}
#if HAVE_PTHREADS
static void *circular_buffer_task( void *_URLContext)
{
URLContext *h = _URLContext;
UDPContext *s = h->priv_data;
fd_set rfds;
struct timeval tv;
while(!s->exit_thread) {
int left;
int ret;
int len;
FD_ZERO(&rfds);
FD_SET(s->udp_fd, &rfds);
tv.tv_sec = 1;
tv.tv_usec = 0;
ret = select(s->udp_fd + 1, &rfds, NULL, NULL, &tv);
if (ret < 0) {
if (ff_neterrno() == AVERROR(EINTR))
continue;
s->circular_buffer_error = AVERROR(EIO);
goto end;
}
if (!(ret > 0 && FD_ISSET(s->udp_fd, &rfds)))
continue;
/* How much do we have left to the end of the buffer */
/* Whats the minimum we can read so that we dont comletely fill the buffer */
left = av_fifo_space(s->fifo);
len = recv(s->udp_fd, s->tmp+4, sizeof(s->tmp)-4, 0);
if (len < 0) {
if (ff_neterrno() != AVERROR(EAGAIN) && ff_neterrno() != AVERROR(EINTR)) {
s->circular_buffer_error = AVERROR(EIO);
goto end;
}
continue;
}
AV_WL32(s->tmp, len);
if(left < len + 4) {
/* No Space left */
if (s->overrun_nonfatal) {
av_log(h, AV_LOG_WARNING, "Circular buffer overrun. "
"Surviving due to overrun_nonfatal option\n");
continue;
} else {
av_log(h, AV_LOG_ERROR, "Circular buffer overrun. "
"To avoid, increase fifo_size URL option. "
"To survive in such case, use overrun_nonfatal option\n");
s->circular_buffer_error = AVERROR(EIO);
goto end;
}
}
pthread_mutex_lock(&s->mutex);
av_fifo_generic_write(s->fifo, s->tmp, len+4, NULL);
pthread_cond_signal(&s->cond);
pthread_mutex_unlock(&s->mutex);
}
end:
pthread_mutex_lock(&s->mutex);
pthread_cond_signal(&s->cond);
pthread_mutex_unlock(&s->mutex);
return NULL;
}
#endif
/* 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;
int len;
int reuse_specified = 0;
h->is_streamed = 1;
h->max_packet_size = 1472;
is_output = !(flags & AVIO_FLAG_READ);
s->ttl = 16;
s->buffer_size = is_output ? UDP_TX_BUF_SIZE : UDP_MAX_PKT_SIZE;
s->circular_buffer_size = 7*188*4096;
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;
reuse_specified = 1;
}
if (av_find_info_tag(buf, sizeof(buf), "overrun_nonfatal", p)) {
char *endptr = NULL;
s->overrun_nonfatal = strtol(buf, &endptr, 10);
/* assume if no digits were found it is a request to enable it */
if (buf == endptr)
s->overrun_nonfatal = 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), "fifo_size", p)) {
s->circular_buffer_size = strtol(buf, NULL, 10)*188;
}
if (av_find_info_tag(buf, sizeof(buf), "localaddr", p)) {
av_strlcpy(localaddr, buf, sizeof(localaddr));
}
}
/* 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;
udp_fd = udp_socket_create(s, &my_addr, &len, 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 || (s->is_multicast && !reuse_specified)) {
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) {
av_log(h, AV_LOG_ERROR, "bind failed: %s\n", strerror(errno));
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 (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(h, 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(h, AV_LOG_WARNING, "setsockopt(SO_RECVBUF): %s\n", strerror(errno));
}
/* 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)) {
av_log(h, AV_LOG_ERROR, "connect: %s\n", strerror(errno));
goto fail;
}
}
s->udp_fd = udp_fd;
#if HAVE_PTHREADS
if (!is_output && s->circular_buffer_size) {
int ret;
/* start the task going */
s->fifo = av_fifo_alloc(s->circular_buffer_size);
ret = pthread_mutex_init(&s->mutex, NULL);
if (ret != 0) {
av_log(h, AV_LOG_ERROR, "pthread_mutex_init failed : %s\n", strerror(ret));
goto fail;
}
ret = pthread_cond_init(&s->cond, NULL);
if (ret != 0) {
av_log(h, AV_LOG_ERROR, "pthread_cond_init failed : %s\n", strerror(ret));
goto cond_fail;
}
ret = pthread_create(&s->circular_buffer_thread, NULL, circular_buffer_task, h);
if (ret != 0) {
av_log(h, AV_LOG_ERROR, "pthread_create failed : %s\n", strerror(ret));
goto thread_fail;
}
s->thread_started = 1;
}
#endif
return 0;
#if HAVE_PTHREADS
thread_fail:
pthread_cond_destroy(&s->cond);
cond_fail:
pthread_mutex_destroy(&s->mutex);
#endif
fail:
if (udp_fd >= 0)
closesocket(udp_fd);
av_fifo_free(s->fifo);
return AVERROR(EIO);
}
static int udp_read(URLContext *h, uint8_t *buf, int size)
{
UDPContext *s = h->priv_data;
int ret;
int avail, nonblock = h->flags & AVIO_FLAG_NONBLOCK;
#if HAVE_PTHREADS
if (s->fifo) {
pthread_mutex_lock(&s->mutex);
do {
avail = av_fifo_size(s->fifo);
if (avail) { // >=size) {
uint8_t tmp[4];
pthread_mutex_unlock(&s->mutex);
av_fifo_generic_read(s->fifo, tmp, 4, NULL);
avail= AV_RL32(tmp);
if(avail > size){
av_log(h, AV_LOG_WARNING, "Part of datagram lost due to insufficient buffer size\n");
avail= size;
}
av_fifo_generic_read(s->fifo, buf, avail, NULL);
av_fifo_drain(s->fifo, AV_RL32(tmp) - avail);
return avail;
} else if(s->circular_buffer_error){
pthread_mutex_unlock(&s->mutex);
return s->circular_buffer_error;
} else if(nonblock) {
pthread_mutex_unlock(&s->mutex);
return AVERROR(EAGAIN);
}
else {
/* FIXME: using the monotonic clock would be better,
but it does not exist on all supported platforms. */
int64_t t = av_gettime() + 100000;
struct timespec tv = { .tv_sec = t / 1000000,
.tv_nsec = (t % 1000000) * 1000 };
if (pthread_cond_timedwait(&s->cond, &s->mutex, &tv) < 0)
return AVERROR(errno == ETIMEDOUT ? EAGAIN : errno);
nonblock = 1;
}
} while( 1);
}
#endif
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;
int ret;
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);
av_fifo_free(s->fifo);
#if HAVE_PTHREADS
if (s->thread_started) {
s->exit_thread = 1;
ret = pthread_join(s->circular_buffer_thread, NULL);
if (ret != 0)
av_log(h, AV_LOG_ERROR, "pthread_join(): %s\n", strerror(ret));
}
pthread_mutex_destroy(&s->mutex);
pthread_cond_destroy(&s->cond);
#endif
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,
};
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