signal handling improvment

httpd.c

@@ -469,7 +469,7 @@ int __cb_main_thread(MYSQL *db, int port_num)
 		sockfd = accept(global_data_handle.httpd_sockfd, (struct sockaddr *)&client_sockaddr, &clilen);
 		if (sockfd == -1) {
 			CM_ERROR("Connection accept error\n");
-			continue;
+			break;
 		} else {
 			DEBUG_MSG("Client accepted connection\n");
 			cb_arg = (struct __cb_args *)malloc(sizeof(struct __cb_args));

signal_handler.c

@@ -4,90 +4,17 @@
 #include <unistd.h> // alarm()
 
 #include "signal_handler.h"
+#include "cm_debug.h"
 #include "cmarketcap.h"
 
-void handle_signal(int signal)
+void handle_SIGINT(int signal)
 {
-	const char *signal_name;
-	sigset_t pending;
-
-	// Find out which signal we're handling
-	switch (signal) {
-		case SIGHUP:
-			signal_name = "SIGHUP";
-			break;
-		case SIGUSR1:
-			signal_name = "SIGUSR1";
-			break;
-		case SIGINT:
-			printf("Caught SIGINT, exiting now\n");
-			close(global_data_handle.httpd_sockfd);
-			exit(0);
-		default:
-			fprintf(stderr, "Caught wrong signal: %d\n", signal);
-			return;
-	}
-
-	/*
-	 * Please note that printf et al. are NOT safe to use in signal handlers.
-	 * Look for async safe functions.
-	 */
-	printf("Caught %s, sleeping for ~3 seconds\n"
-	  "Try sending another SIGHUP / SIGINT / SIGALRM "
-	  "(or more) meanwhile\n", signal_name);
-
-	/*
-	 * Indeed, all signals are blocked during this handler
-	 * But, at least on OSX, if you send 2 other SIGHUP,
-	 * only one will be delivered: signals are not queued
-	 * However, if you send HUP, INT, HUP,
-	 * you'll see that both INT and HUP are queued
-	 * Even more, on my system, HUP has priority over INT
-	 */
-	do_sleep(3);
-	printf("Done sleeping for %s\n", signal_name);
-
-	// So what did you send me while I was asleep?
-	sigpending(&pending);
-	if (sigismember(&pending, SIGHUP)) {
-		printf("A SIGHUP is waiting\n");
-	}
-	if (sigismember(&pending, SIGUSR1)) {
-		printf("A SIGUSR1 is waiting\n");
-	}
-
-	printf("Done handling %s\n\n", signal_name);
-} /* handle_signal */
-
-void handle_sigalrm(int signal)
-{
-	if (signal != SIGALRM) {
-		fprintf(stderr, "Caught wrong signal: %d\n", signal);
-	}
-
-	printf("Got sigalrm, do_sleep() will end\n");
+	printf("Caught SIGINT, exiting now\n");
+	close(global_data_handle.httpd_sockfd);
 }
 
-void do_sleep(int seconds)
+void init_sighandlers()
 {
-	struct sigaction sa;
-	sigset_t mask;
-
-	sa.sa_handler = &handle_sigalrm; // Intercept and ignore SIGALRM
-	sa.sa_flags   = SA_RESETHAND;    // Remove the handler after first signal
-	sigfillset(&sa.sa_mask);
-	sigaction(SIGALRM, &sa, NULL);
-
-	// Get the current signal mask
-	sigprocmask(0, NULL, &mask);
-
-	// Unblock SIGALRM
-	sigdelset(&mask, SIGALRM);
-
-	// Wait with this mask
-	alarm(seconds);
-	sigsuspend(&mask);
-
-	printf("sigsuspend() returned\n");
+	if (signal(SIGINT, handle_SIGINT) == SIG_ERR)
+		CM_ERROR("can't catch SIGINT\n");
 }
-

signal_handler.h

@@ -1,9 +1,8 @@
 #ifndef SIGNAL_HANDLER_H_
 #define SIGNAL_HANDLER_H_
 
-extern void handle_signal(int signal);
-extern void handle_sigalrm(int signal);
-extern void do_sleep(int seconds);
+extern void handle_SIGINT(int signal);
+extern void init_sighandlers();
 
 #endif