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/* SPDX-License-Identifier: BSD-3-Clause */
/*
* Copyright © 2010, Zed A. Shaw.
* Copyright © 2020 rsiddharth <s@ricketyspace.net>
*/
#include <nserve.h>
#include <nsocket.h>
#include <signal.h>
#include <sys/wait.h>
#define BACKLOG 10
void handle_sigchild(int sig)
{
sig = 0; // ignore it
while(waitpid(-1, NULL, WNOHANG) > 0) {
}
}
int setup_sigaction()
{
struct sigaction sa = {
.sa_handler = handle_sigchild,
.sa_flags = SA_RESTART | SA_NOCLDSTOP
};
sigemptyset(&sa.sa_mask);
int rc = sigaction(SIGCHLD, &sa, 0);
check(rc != -1, "signal handler setup failed.");
return 0;
error:
return -1;
}
int main(void)
{
int rc = 0;
int sockfd_s = 0, sockfd_c = 0;
struct sockaddr sockaddr_c;
socklen_t sockaddr_c_len;
pid_t pidc;
// create a sigaction that handles SIGCHLD
rc = setup_sigaction();
check(rc != -1, "sigaction setup failed");
sockfd_s = get_socket();
check(sockfd_s > 0, "nserver: unable to get socket");
rc = listen(sockfd_s, BACKLOG);
check(rc == 0, "nserver: listen failed");
do {
printf("Waiting for connection...\n");
sockfd_c = accept(sockfd_s, &sockaddr_c, &sockaddr_c_len);
pidc = fork();
check(pidc != -1, "nserver: fork failed");
if (pidc == 0) {
close(sockfd_s);
nserve(sockfd_c);
}
rc = close(sockfd_c);
check(rc == 0, "nserver: close failed");
} while(1);
rc = close(sockfd_s);
check(rc == 0, "nserver: close failed");
return 0;
error:
if (sockfd_s) {
rc = close(sockfd_s);
}
if (sockfd_c) {
rc = close(sockfd_c);
}
return -1;
}
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