udp: buffer datagrams in circular buffer instead of a bytestream

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This commit is contained in:
Michael Niedermayer 2011-08-25 21:33:54 +02:00
parent abe0b8e9f3
commit 20f0bf8cfb

View File

@ -30,6 +30,7 @@
#include "avio_internal.h"
#include "libavutil/parseutils.h"
#include "libavutil/fifo.h"
#include "libavutil/intreadwrite.h"
#include <unistd.h>
#include "internal.h"
#include "network.h"
@ -47,6 +48,9 @@
#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;
@ -65,11 +69,10 @@ typedef struct {
#if HAVE_PTHREADS
pthread_t circular_buffer_thread;
#endif
uint8_t tmp[UDP_MAX_PKT_SIZE+4];
int remaining_in_dg;
} 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)
{
@ -347,26 +350,23 @@ static void *circular_buffer_task( void *_URLContext)
/* 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);
left = FFMIN(left, s->fifo->end - s->fifo->wptr);
/* No Space left, error, what do we do now */
if( !left) {
if(left < UDP_MAX_PKT_SIZE + 4) {
av_log(h, AV_LOG_ERROR, "circular_buffer: OVERRUN\n");
s->circular_buffer_error = EIO;
return NULL;
}
len = recv(s->udp_fd, s->fifo->wptr, left, 0);
left = FFMIN(left, s->fifo->end - s->fifo->wptr);
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 = EIO;
return NULL;
}
}
s->fifo->wptr += len;
if (s->fifo->wptr >= s->fifo->end)
s->fifo->wptr = s->fifo->buffer;
s->fifo->wndx += len;
AV_WL32(s->tmp, len);
av_fifo_generic_write(s->fifo, s->tmp, len+4, NULL);
}
return NULL;
@ -544,11 +544,17 @@ static int udp_read(URLContext *h, uint8_t *buf, int size)
do {
avail = av_fifo_size(s->fifo);
if (avail) { // >=size) {
uint8_t tmp[4];
// Maximum amount available
size = FFMIN( avail, size);
av_fifo_generic_read(s->fifo, buf, size, NULL);
return size;
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);
return avail;
}
else {
FD_ZERO(&rfds);