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udp: add a thread into udp.c for receiving data into a circular buffer, this stops the problem of live decoding/encoding giving errors.

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Also added a buf_size which is the number of TS packets that to be allocated for the circular buffer.
This commit is contained in:
JULIAN GARDNER 2011-05-13 16:28:42 +02:00 committed by Michael Niedermayer
parent 4d15f194b4
commit 4275602183
1 changed files with 155 additions and 1 deletions
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156
libavformat/udp.c
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@ -34,6 +34,9 @@
#include "network.h"
#include "os_support.h"
#include "url.h"
#include <pthread.h>
#include <semaphore.h>
#include <sys/resource.h>
#include <sys/time.h>
#ifndef IPV6_ADD_MEMBERSHIP
@ -51,8 +54,22 @@ typedef struct {
struct sockaddr_storage dest_addr;
int dest_addr_len;
int is_connected;
/* Circular Buffer variables for use in UDP receive code */
unsigned char *circular_buffer;
int circular_buffer_head;
int circular_buffer_size;
int circular_buffer_tail;
int circular_buffer_available;
int circular_buffer_available_max;
int circular_buffer_error;
pthread_t circular_buffer_thread;
sem_t circular_buffer_semaphore;
} UDPContext;
#define min(X,Y) ((X)<(Y) ? (X):(Y))
#define max(X,Y) ((X)>(Y) ? (X):(Y))
#define UDP_TX_BUF_SIZE 32768
#define UDP_MAX_PKT_SIZE 65536
@ -298,6 +315,69 @@ static int udp_get_file_handle(URLContext *h)
return s->udp_fd;
}
static void *circular_buffer_task( void *_URLContext)
{
URLContext *h = _URLContext;
UDPContext *s = h->priv_data;
fd_set rfds;
struct timeval tv;
for(;;) {
int left;
int ret;
int len;
if (url_interrupt_cb()) {
s->circular_buffer_error = EINTR;
return NULL;
}
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 = EIO;
return NULL;
}
if (!(ret > 0 && FD_ISSET(s->udp_fd, &rfds)))
continue;
/* How much do we have left to the end of the buffer */
left = s->circular_buffer_size-s->circular_buffer_head;
/* Whats the minimum we can read so that we dont comletely fill the buffer */
sem_wait( &s->circular_buffer_semaphore);
left = min( left, s->circular_buffer_size-s->circular_buffer_available);
sem_post( &s->circular_buffer_semaphore );
/* No Space left, error, what do we do now */
if( !left) {
av_log(h, AV_LOG_ERROR, "circular_buffer: OVERRUN\n");
s->circular_buffer_error = EIO;
return NULL;
}
len = recv(s->udp_fd, s->circular_buffer+s->circular_buffer_head, left, 0);
if (len < 0) {
if (ff_neterrno() != AVERROR(EAGAIN) && ff_neterrno() != AVERROR(EINTR)) {
s->circular_buffer_error = EIO;
return NULL;
}
}
s->circular_buffer_head += len;
sem_wait( &s->circular_buffer_semaphore);
s->circular_buffer_available += len;
s->circular_buffer_available_max = max( s->circular_buffer_available_max, s->circular_buffer_available);
sem_post( &s->circular_buffer_semaphore );
if( s->circular_buffer_head>=s->circular_buffer_size)
s->circular_buffer_head -= s->circular_buffer_size;
}
return NULL;
}
/* put it in UDP context */
/* return non zero if error */
static int udp_open(URLContext *h, const char *uri, int flags)
@ -325,10 +405,12 @@ static int udp_open(URLContext *h, const char *uri, int flags)
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)) {
const char *endptr=NULL;
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)
@ -350,6 +432,9 @@ static int udp_open(URLContext *h, const char *uri, int flags)
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), "buf_size", p)) {
s->circular_buffer_size = strtol(buf, NULL, 10)*188;
}
}
/* fill the dest addr */
@ -431,10 +516,28 @@ static int udp_open(URLContext *h, const char *uri, int flags)
}
s->udp_fd = udp_fd;
if (!is_output && s->circular_buffer_size) {
/* start the task going */
s->circular_buffer = av_malloc( s->circular_buffer_size);
if (sem_init( &s->circular_buffer_semaphore, PTHREAD_PROCESS_PRIVATE, 1 )) {
av_log(h, AV_LOG_ERROR, "sem_init failed\n");
goto fail;
}
if (pthread_create(&s->circular_buffer_thread, NULL, circular_buffer_task, h)) {
av_log(h, AV_LOG_ERROR, "pthread_create failed\n");
goto fail;
}
}
return 0;
fail:
if (udp_fd >= 0)
closesocket(udp_fd);
if (s->circular_buffer) {
sem_destroy( &s->circular_buffer_semaphore);
av_free( s->circular_buffer);
}
av_free(s);
return AVERROR(EIO);
}
@ -443,6 +546,51 @@ static int udp_read(URLContext *h, uint8_t *buf, int size)
{
UDPContext *s = h->priv_data;
int ret;
int avail;
int left;
fd_set rfds;
struct timeval tv;
if (s->circular_buffer_thread) {
do {
sem_wait( &s->circular_buffer_semaphore );
avail = s->circular_buffer_available;
sem_post( &s->circular_buffer_semaphore );
if (avail) { // >=size) {
// Maximum amount available
size = min( avail, size);
// Whats left till the end of the circular buffer
left = s->circular_buffer_size-s->circular_buffer_tail;
// How much do we need, all?
left = min( left, size);
// Get the first block
memcpy( buf, s->circular_buffer+s->circular_buffer_tail, left);
// Have we any more, this will be from the start of the buffer
if (size-left)
memcpy( buf+left, s->circular_buffer, size-left);
// Check for the tail wrapping around
s->circular_buffer_tail += size;
if( s->circular_buffer_tail>=s->circular_buffer_size)
s->circular_buffer_tail -= s->circular_buffer_size;
// Update the available amount
sem_wait( &s->circular_buffer_semaphore );
s->circular_buffer_available -= size;
sem_post( &s->circular_buffer_semaphore );
return size;
}
else {
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)
return ret;
}
} while( 1);
}
if (!(h->flags & AVIO_FLAG_NONBLOCK)) {
ret = ff_network_wait_fd(s->udp_fd, 0);
@ -450,6 +598,7 @@ static int udp_read(URLContext *h, uint8_t *buf, int size)
return ret;
}
ret = recv(s->udp_fd, buf, size, 0);
return ret < 0 ? ff_neterrno() : ret;
}
@ -481,6 +630,11 @@ static int udp_close(URLContext *h)
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);
if (s->circular_buffer) {
sem_destroy( &s->circular_buffer_semaphore);
av_free( s->circular_buffer);
av_log( h, AV_LOG_INFO, "circular_buffer_info max:%d%%\r\n", (s->circular_buffer_available_max*100)/s->circular_buffer_size);
}
av_free(s);
return 0;
}