Offtopic : Need help with C program

[Stefan Sonnenberg-Carstens <ssc_(_at_)_coolspot_(_dot_)_de>]

I saw the attached C source was removed in MARC.
So here it is again.
The problem is that the program sometimes creates zombie processes
when I do something like :

while true ; do curl http://localhost:8271/ >/dev/null ; done

And I can't see why.

Thx in advance.


#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/wait.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <netdb.h>
#include <string.h>
#include <errno.h>
#include <signal.h>
#include <pwd.h>

int daemonize();

int serversocket_new(char *hostname,int port);

void handle_request(int clientsocket);


void session_new();

void sigchild(int signal) { wait(NULL); } 

int main(int argc,char **argv) {
	running = 1;
	signal(SIGCHLD,sigchild);
	int server = 0;
	int client = 0;
	int numclients = 0;
	struct sockaddr_in client_addr;
	int client_addr_len = sizeof(struct sockaddr_in);

	daemonize();
	server = serversocket_new("localhost",8271);

	for(;;) { 
		client = accept(server,(struct sockaddr *) &client_addr,&client_addr_len); 
		int pid=0;
		pid = fork();
		if(pid < 0) {
			printf("Can't fork.\n");
			exit(1);
		}
		if(pid == 0) {
			session_new();
			handle_request(client);
			exit(0);
		}
		close(client);
	}
	return 0;
}


void handle_request(int clientsocket) {
	FILE *f;
	char buf[1024];
	char *msg = "Content-type: text/html\r\n\r\nTest\n";
	char *status = "HTTP/1.0 200 OK\n";
	f = fdopen(clientsocket,"w+");
	if(f == NULL) {
		printf("Can't create socket from file.\n");
		exit(0);
	}
	memset(buf,'\0',1024);
	read(clientsocket,buf,1024);
	fputs(status,f);
	fputs(msg,f);
	fflush(f);
	fclose(f);
}

void session_new() {
	fclose(stdin);
	fclose(stdout);
	fclose(stderr);
	setsid();
}

void drop_privileges() {
	struct passwd *pass;
	pass = getpwnam("nobody");
	setgid(pass->pw_gid);
	setuid(pass->pw_uid);
}

int daemonize() {
	int pid = 0;
	pid = fork();
	if(pid<0) {
		exit(pid);
	}
	if(pid)
		exit(0);
	setsid();
	return 0;
}

int serversocket_new(char *hostname,int port) {
	int res = 0;
	int server = 0;
	int ipv4addr = 0;
	struct hostent *host = 0;
	struct in_addr *ipaddr = 0;
	struct sockaddr_in serveraddr;

	server = socket(PF_INET,SOCK_STREAM,IPPROTO_TCP);
	if(!server) {
		exit(1);
	}
	host = gethostbyname(hostname);
	if(!host) {
		exit(1);
	}
	ipaddr = (struct in_addr *) host->h_addr;
	serveraddr.sin_addr = *ipaddr;
	serveraddr.sin_port = htons(port); 
	res = bind(server,(struct sockaddr *) &serveraddr,sizeof(struct 
sockaddr_in));	
	if(res) {
		exit(1);
	}
	res = listen(server,5);
	if(res) {
		exit(1);
	}
	return server;
}