/*
C socket server example, handles multiple clients using threads */
#include<stdio.h>
#include<string.h> //strlen
#include<stdlib.h> //strlen
#include<sys/socket.h>
#include<arpa/inet.h> //inet_addr
#include<unistd.h>
#//write
#include<pthread.h>
#include "daq.h"
#define PORT 9930
//the thread function
void *connection_handler(void *);
int is_connected = 0;
int ncalls=0;
extern int ctrl_c;
int writesock(int sock, int id , char *msg, int len ){
int hdr[2];
hdr[0]= id;
hdr[1]= len + 8;
write(sock , hdr , 8);
return write(sock , msg , len);
}
int main(int argc , char *argv[]) {
int socket_desc , client_sock , c , *new_sock=NULL;
struct sockaddr_in server , client;
if (argc >1) return daq_main(argc, argv);
//Create socket
socket_desc = socket(AF_INET , SOCK_STREAM , 0);
if (socket_desc == -1)
{
printf("Could not create socket");
}
//Prepare the sockaddr_in structure
server.sin_family = AF_INET;
server.sin_addr.s_addr = INADDR_ANY;
server.sin_port = htons( PORT );
//Bind
if( bind(socket_desc,(struct sockaddr *)&server , sizeof(server)) < 0)
{
//print the error message
return 1;
}
//Listen
listen(socket_desc , 3);
//Accept and incoming connection
puts("Waiting for incoming connections...");
c = sizeof(struct sockaddr_in);
//Accept and incoming connection
puts("Waiting for incoming connections...");
c = sizeof(struct sockaddr_in);
while( (client_sock = accept(socket_desc, (struct sockaddr *)&client, (socklen_t*)&c)) )
{
puts("Connection accepted");
pthread_t sniffer_thread;
if (is_connected){
char message[0xFF]="Only one client can connect. Disconnect it first!";
writesock
(client_sock
, 0, message
, strlen(message
));
close (client_sock);
continue;
}
*new_sock = client_sock;
if( pthread_create( &sniffer_thread , NULL , connection_handler , (void*) new_sock) < 0)
{
perror("could not create thread");
return 1;
}
//Now join the thread , so that we dont terminate before the thread
//pthread_join( sniffer_thread , NULL);
puts("Handler assigned");
}
if (client_sock < 0)
{
return 1;
}
return 0;
}
void *daq_handler(void *rdata){
pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL);
//Get the socket descriptor
int sock = *(int*)rdata;
int *idata = (int *)rdata;
char * settings = (char *) (idata+2);
daq_init(settings);
settings +=12;
int bufsize = 0;
char * data = NULL;
//for(int i =0;i<5;i++) printf("%d %d\n",i, idata[i]);
while (1){
int nb = daq_run ( settings, &data, &bufsize );
int error = 0;
socklen_t len = sizeof (error);
int retval = getsockopt (sock, SOL_SOCKET, SO_ERROR, &error, &len);
if (retval!=0 || error!=0) break;
writesock(sock , 1, data , nb );
if (ctrl_c) break;
//break;
}
if (data
!=NULL
) free(data
);
fprintf(stderr
, "Exiting thread %d\n", sock
) ;
return NULL;
}
/*
* This will handle connection for each client
* */
void *connection_handler(void *socket_desc) {
//Get the socket descriptor
int sock = *(int*)socket_desc;
int read_size;
char *message , client_message[2000];
is_connected = 1;
//Send some messages to the client
message = "Info from connection handler\n";
writesock
(sock
, 0, message
, strlen(message
));
//Receive a message from client
pthread_t daq_thread = 0;
while( (read_size = recv(sock , client_message , 2000 , 0)) > 0 )
{
//Send the message back to client
int * hdr = (int *) client_message;
printf("Received %d bytes RECID = %d LEN %d\n",read_size
, hdr
[0], hdr
[1]);
switch (hdr[0]){
case 0:
ctrl_c = 0;
hdr[0]= sock;
if( pthread_create( &daq_thread , NULL , daq_handler , (void*) &client_message) < 0)
{
perror("could not create daq thread");
}
break;
case 1:
ctrl_c = 1;
sleep(1);
if (daq_thread) {
pthread_cancel(daq_thread);
daq_thread = 0;
}
break;
default: break;
}
}
if(read_size == 0)
{
puts("Client disconnected");
}
else if(read_size == -1)
{
}
if (daq_thread) {
pthread_cancel(daq_thread);
daq_thread = 0;
}
//Free the socket pointer
socket_desc = 0;
is_connected = 0;
return 0;
}