Produser Consumer wthout semaphore - multithreading

Question

I am trying to solve producer consumer problem using threads without semaphoere.In my client i create 4 threads 2 for producer and 2 for consumer, each of them send M produce/consume messages. Here is my client code.
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <errno.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <netinet/in.h>
#include <pthread.h>
#define BUFSIZE 4096
#define N 4
/*
** Client
*/
int M = 10;
pthread_t threads[N];
char buf[BUFSIZE];
char *service;
char *host = "localhost";
int cc;
int csock;
int consumed,produced;
void *connect_and_handle(void *msg){
/* Create the socket to the controller */
if ( ( csock = connectsock( host, service, "tcp" )) == 0 ) {
fprintf( stderr, "Cannot connect to server.\n" );
exit( -1 );
}
printf( "The server is ready, please start entering commands.\n" );
fflush( stdout );
// Start the loop
int k;
//char msg[50];
for (k=0;k<M;k++){
strcpy(buf, msg);
// Send to the server
if ( write( csock, buf, strlen(buf) ) < 0 ) {
fprintf( stderr, "client write failed: %s\n", strerror(errno) );
exit( -1 );
}
if ( (cc = read( csock, buf, BUFSIZE )) <= 0 )
break;
buf[cc] = 0;
printf( "Server replied: %s\n", buf );
}
close( csock );
// exit thread
pthread_exit(NULL);
}
int main( int argc, char *argv[] ){
char *msg, *msg2;
switch( argc ) {
case 2:
service = argv[1];
break;
case 3:
host = argv[1];
service = argv[2];
break;
default:
fprintf( stderr, "usage: chat [host] port\n" );
exit(-1);
}
// thread code goes here
int i, n = N;
for (i=0;i<N;i++){
msg = (char*)malloc(32*sizeof(char));
msg2 = (char*)malloc(32*sizeof(char));
sprintf(msg,"PRODUCE This is the item #%i", i);
sprintf(msg2, "CONSUME");
//producer thread
produced = pthread_create( &threads[i], NULL, connect_and_handle, (void *) msg );
if ( produced != 0 ) { printf( "Error: pthread_create returned code %d.\n", produced); exit( -1 );}
//consumer thread
/*
i++;
consumed = pthread_create( &threads[i], NULL, connect_and_handle, (void *) msg2 );
if ( consumed != 0 ){ printf( "Error: pthread_create returned code %d.\n", consumed ); exit( -1 );}
*/
}
}
and server :
// This server implements part of the 333 protocol
// NUMBER - number of clients served
// NAMES - developers
// GOODBYE - close connection
// ADD - increment
// SUBTRACT- decrement
//
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <pthread.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <netinet/in.h>
#include <semaphore.h>
#define QLEN 5
#define BUFSIZE 4096
#define MAX 100
/*
** This server ... is threaded
*/
// Function prototypes
int passivesock( char *, char *, int, int * );
void *handle_a_client( void *arg );
// Global variables are shared by the threads
int clients = 0;
char *buffer[MAX];
char *maloc_buf;
int count=0;
int full_count=0;
int empty_count=MAX;
int main( int argc, char *argv[] ) {
char *service;
struct sockaddr_in fsin;
int alen;
int msock;
int ssock;
int rport = 0;
switch (argc) {
case 1:
// No args? let the OS choose a port and tell the user
rport = 1;
break;
case 2:
// User provides a port? then use it
service = argv[1];
break;
default:
fprintf( stderr, "usage: server [port]\n" );
exit(-1);
}
msock = passivesock( service, "tcp", QLEN, &rport );
if (rport) {
// Tell the user the selected port
printf( "server: port %d\n", rport );
fflush( stdout );
}
// Keep accepting clients until you are killed
for (;;) {
int ssock;
pthread_t pid;
alen = sizeof(fsin);
ssock = accept( msock, (struct sockaddr *)&fsin, &alen );
if (ssock < 0) {
fprintf( stderr, "accept: %s\n", strerror(errno) );
exit(-1);
}
clients++;
printf("connected , %i", clients);
// Launch a thread to manage this client
// YES, pid is getting overwritten each time, but it is unused
pthread_create( &pid, NULL, handle_a_client, (void *) ssock );
}
}
void *handle_a_client( void *arg ) {
char requestbuf[BUFSIZE];
char replybuf[BUFSIZE];
int ssock = (int) arg;
int cc;
for (;;) {
if ( (cc = read( ssock, requestbuf, BUFSIZE )) <= 0 ) {
printf( "The client has gone.\n");
(void) close(ssock);
pthread_exit(0);
break;
}
else {
// Remove the newline and null-terminate the string
requestbuf[cc] = '\0';
int size = cc-7;
printf( "The client on %d says: %s\n", ssock, requestbuf );
if ( strncasecmp( requestbuf, "goodbye", 7 ) == 0 ) {
close( ssock );
break;
}
else if ( strncasecmp( requestbuf, "PRODUCE", 7 ) == 0 ) {
if (full_count == MAX){
strcpy(replybuf,"FULL\n");
write(ssock,replybuf,strlen(replybuf));
}
else {
maloc_buf=(char*) malloc((size)*sizeof(char));
strcpy(maloc_buf, (requestbuf+8));
buffer[full_count]=maloc_buf;
int num=full_count+1;
sprintf(replybuf, "Client produced item no%i: %s",full_count, buffer[full_count]);
full_count++;
empty_count--;
}
}
else if ( strncasecmp( requestbuf, "CONSUME", 7 ) == 0 ) {
if (empty_count == MAX) {
strcpy(replybuf,"EMPTY\n");
write( ssock, replybuf, strlen(replybuf) );
}
else {
sprintf(replybuf,"OK %s", buffer
[full_count]);
free(buffer[full_count]);
full_count--;
empty_count++;
}
}
}
}
}
When i run my server and then try to connect to it in client, nothing happens. Debugging showed (i am not sure) that in client code after
if ( ( csock = connectsock( host, service, "tcp" )) == 0 ) {
i am exiting, nothing is printed to console both in client and server.