I basically want to inform main that a client disconnected in order to decrement the thread counter. Right now my program is setup to only create a certain number of threads to serve the connecting clients. If the client disconnects the thread count needs to be decremented so that it does not max out and not allow further threads to be made for waiting clients.
Now I can use a global variable, but I am doing this to learn more about Unix system programming and I thought either pipes or message queues would be interesting to try out. My problem is I am not sure how my code can utilize this to send information from child thread to main thread.
I wrote some quick and dirty code as an to test out different ways of what I need to do.
In my code I commented where I want to send message back to main process.
I have client code if you do need I can post, but the code below should be sufficient.
Thanks for any help!
Code:
#include <stdio.h>
#include <pthread.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <strings.h>
#include <stdlib.h>
#include <unistd.h>
#define BUFFERSIZE 512
#define NTHREADS 10
#define SERVER_PORT 6001
#define POOL_SIZE 5
void *main_client_thread(void *arg);
typedef struct mainthreadArg
{
int csocketId;
int threadCounter;
}mtArg;
int main(int argc, char** argv)
{
int csock, ssock;
socklen_t addr_len;
pthread_t cthread[NTHREADS];
struct sockaddr_in addr;
bzero((void *)&addr, sizeof(addr));
addr.sin_family = AF_INET;
addr.sin_port = htons(SERVER_PORT);
addr.sin_addr.s_addr = htonl(INADDR_ANY);
addr_len = sizeof(addr);
/* socket */
if((ssock=socket(PF_INET, SOCK_STREAM, 0))==-1)
{
fprintf(stderr,"Unable to create server socket\n");
exit(1);
}
/* bind */
if(bind(ssock, (struct sockaddr *)&addr, sizeof(addr))==-1)
{
fprintf(stderr,"bind failed.\n");
exit(1);
}
/* listen */
if(listen(ssock, POOL_SIZE)==-1)
{
fprintf(stderr, "listen failed.\n");
exit(1);
}
mtArg ta;
ta.threadCounter = 0; /* thread counter */
/* main loop to manage clients */
while(1)
{
if(ta.threadCounter > NTHREADS)
{
printf("No more threads can be created. Sorry\n");
exit(1);
}
/* accept */
if((csock=accept(ssock, (struct sockaddr *)&addr, &addr_len))==-1)
{
fprintf(stderr, "accept failed.\n");
exit(1);
}
ta.csocketId = csock;
if((pthread_create(&cthread[ta.threadCounter], NULL, main_client_thread, &ta)) != 0)
{
fprintf(stdout, "pthread was not created\n");
exit(0);
}
ta.threadCounter++;
}
return 0;
}
void *main_client_thread(void *arg)
{
mtArg t = *(mtArg *)arg;
int cli,cnt;
cli = t.csocketId;
cnt = t.threadCounter;
int stayConnected = 1;
int nread;
/* int nwrite; */
char buffer[BUFFERSIZE];
while(stayConnected == 1)
{
bzero(buffer, sizeof(buffer));
if((nread=read(cli, buffer, BUFFERSIZE)) > 0)
{
printf("Thread %d read %d bytes from client.\n", t.threadCounter, nread);
printf("Thread %d buffer=%s\n", t.threadCounter, buffer);
}
else /* client disconnected */
{
printf("nread failed.\n");
t.threadCounter--;
/* report back to main thread so that thread counter is decremented */
/* use pipe or message queue for this */
stayConnected = 0;
}
}
return NULL;
}
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LEARN ABOUT DEBIAN
holdingnuts
HOLDINGNUTS(6) HoldingNuts manual HOLDINGNUTS(6)NAME
HoldingNuts - a poker client and server
SYNOPSIS
holdingnuts [-c config-dir ]
DESCRIPTION
HoldingNuts is an open source multi-platform poker client and server.
You can play the popular Texas Hold'em variant with people all over the world, meet your friends, run your own games and even setup your
own poker-network.
This is the client part which is used to connect to a running instance of the holdingnuts-server(6) game-server.
OPTIONS -c config-dir
Use an alternate config-dir instead of the default ~/.holdingnuts.
FILES
~/.holdingnuts/client.cfg
The default client configuration file.
~/.holdingnuts/client.log
The default client log file.
WWW
The project webpage: http://www.holdingnuts.net/
The project wiki: http://wiki.holdingnuts.net/
The online manual: http://wiki.holdingnuts.net/manual
AUTHOR
Dominik Geyer <dominik.geyer@holdingnuts.net> is the main author, but the whole list of contributors is found at
http://www.holdingnuts.net/about
SEE ALSO holdingnuts-server(6)Dominik Geyer Version 0.0.5 HOLDINGNUTS(6)