server.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <netinet/in.h>
#include <unistd.h>
#include <signal.h>
#include <assert.h>

#define SRV_ADDR "0.0.0.0"
#define SRV_PORT 9001

void handle_client(int sock)
{
	char *args[] = { "sbox", NULL };

	dup2(sock, 0); dup2(sock, 1); dup2(sock, 2);
	//close(0); close(1); close(2);

	execv(args[0], args);
	perror("execv");
}

void child_handler(int signo)
{
  printf("Child exit (%d)\n", signo);
}

void segv_handler(int signo)
{
	printf("SIGSEGV (%d)\n", signo);
	exit(EXIT_FAILURE);
}

void abrt_handler(int signo)
{
	printf("SIGABRT (%d)\n", signo);
	exit(EXIT_FAILURE);
}

int srv_run()
{
	struct sockaddr_in sin;
	struct sockaddr_in cin;
	int srv_fd, cln_fd;
	int tmp;
	int sop;

	srv_fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
	assert(srv_fd > 0);

	sop = 1;
	setsockopt(srv_fd, SOL_SOCKET, SO_REUSEADDR, (void*) &sop, sizeof(sop));

	sin.sin_addr.s_addr = inet_addr(SRV_ADDR);
	sin.sin_port = htons(SRV_PORT);
	sin.sin_family = AF_INET;

	assert(!bind(srv_fd, (struct sockaddr*) &sin, sizeof(sin)));
	listen(srv_fd, 100);

	//signal(SIGCHLD, child_handler);
	signal(SIGCHLD, SIG_IGN);

	while(1) {
		tmp = sizeof(cin);
		cln_fd = accept(srv_fd, (struct sockaddr*) &cin, &tmp);
		if(cln_fd < 0)
			continue;

		printf("Received connection from %s:%d\n", (char*) inet_ntoa(cin.sin_addr), ntohs(cin.sin_port));
		if(!fork()) {
			printf("Processing client: pid: %d socket: %d\n", getpid(), cln_fd);

			//signal(SIGSEGV, segv_handler);
			//signal(SIGABRT, abrt_handler);
			
			close(srv_fd);
			handle_client(cln_fd);

			shutdown(cln_fd, SHUT_RDWR);
			close(cln_fd);

			exit(0);
		}

		close(cln_fd);
	}
}

int main(int argc, char **argv)
{
	return srv_run();
}