/*
* Read data from the network.
* Write data to ring buffer.
*/
void receive_packets(int fifo)
{
socket_t sock = setup_network_listener();
int numbytes, bytesinfifo;
struct sockaddr_storage their_addr;
char buf[PACKET_SIZE_BYTES];
size_t addr_len;
//char s[INET6_ADDRSTRLEN];
int numpackets=0;
long long totalbytes=0;
long long currentpacket=0;
long long newpacket=0;
long long errors=0;
int i;
fprintf(stderr, "Entering network thread loop.\n");
/*
* loop forever:
* read data from network
*/
while(run_net_thread)
{
//printf("listener: waiting to recvfrom...\n");
if ((numbytes = recvfrom(sock, buf, PACKET_SIZE_BYTES , 0,
(struct sockaddr *)&their_addr, (socklen_t *) &addr_len)) == -1) {
if(errno==EINTR && run_net_thread==0)
{
perror("Interrupt received and handled");
}
else
{
perror("Unable to receive packet");
exit(1);
}
}
else
{
/*
debug_fprintf(stderr, "[net thread] Received %d bytes.\n", numbytes);
debug_fprintf(stderr, "listener: got packet from %s\n",
inet_ntop(their_addr.ss_family,
get_in_addr((struct sockaddr *)&their_addr),
s, sizeof s));
debug_fprintf(stderr,"listener: packet is %d bytes long\n", numbytes);
debug_fprintf(stderr,"listener: packet contains \"%s\"\n", buf);
*/
//send packets over the fifo
//bytesinfifo = write(fifo, buf, numbytes);
//debug_fprintf(stderr, "wrote %d bytes to fifo\n", bytesinfifo);
numpackets++;
totalbytes+=numbytes;
newpacket = ntohll(((uint64_t *) buf)[PACKET_SIZE_BYTES/8-1]);
if(currentpacket+1 != newpacket)
{
errors++;
}
currentpacket = newpacket;
}
}
for(i=0;i<PACKET_SIZE;i++)
{
fprintf(stderr, "%lld ", ntohll(((uint64_t *) buf)[i]));
}
fprintf(stderr, "Exiting network thread loop.\n");
fprintf(stderr, "Received %d packets, %lld bytes, %lld errors\n", numpackets, totalbytes, errors);
close(sock);
return;
}
void *net_thread_function(void *arg) {
/* This thread puts data into a ring buffer from a socket*/
BufferSocket *bs = (BufferSocket *)arg;
RING_ITEM *this_slot;
socket_t sock = setup_network_listener((short) bs->port);
SA_in addr; // packet source's address
socklen_t addr_len = sizeof(addr);
ssize_t num_bytes = 0;
fd_set readset;
struct timeval tv;
struct timespec ts;
long timeouts = 0;
// If sock open fails, end all threads
if (sock == -1) {
fprintf(stderr, "Unable to open socket.\n");
bs->run_threads = 0;
return NULL;
}
while (bs->run_threads) {
this_slot = bs->buf->write_ptr;
if (clock_gettime(CLOCK_REALTIME, &ts) == -1) {
fprintf(stderr, "Net: clock_gettime returned nonzero.\n");
bs->run_threads = 0;
continue;
}
ts.tv_nsec += TIMEOUT_USEC*1000;
// Wait for next buffer slot to open up
if (sem_timedwait(&this_slot->write_mutex, &ts) == -1) continue;
// Poll to see if socket has data
while (bs->run_threads) {
FD_ZERO(&readset);
FD_SET(sock, &readset);
tv.tv_sec = 0; tv.tv_usec = TIMEOUT_USEC;
num_bytes = select(sock + 1, &readset, NULL, NULL, &tv);
// Read data from socket into ring buffer
if (num_bytes > 0) {
num_bytes = recvfrom(sock, this_slot->data,
bs->buf->buffer_size / bs->buf->list_length,
0, (SA *)&addr, &addr_len);
timeouts = 0;
break;
} else if (num_bytes < 0) {
if (errno == EINTR) continue;
fprintf(stderr, "Unable to receive packets.\n");
bs->run_threads = 0;
} else { // num_bytes == 0
timeouts += TIMEOUT_USEC;
if(timeouts >= 60*1000*1000) {
fprintf(stdout, "No packets received for 60 seconds on port %d.\n", bs->port);
syslog(LOG_WARNING, "no packets received for 60 seconds on port %d\n", bs->port);
// Send self the INT signal (simulate ctrl-c)
raise(SIGINT);
timeouts = 0;
}
}
//printf("run_threads=%d num_bytes=%d errno=%d(%d)\n", bs->run_threads, num_bytes, errno, EINTR);
}
if (num_bytes > 0) {
//printf("Wrote in a packet: size=%d slot=%d\n", num_bytes, this_slot - bs->buf->list_ptr);
this_slot->size = num_bytes;
// Mark this slot ready for readout
sem_post(&this_slot->read_mutex);
bs->buf->write_ptr = this_slot->next;
}
}
close(sock);
return NULL;
}
