re-write SIGTERM handling

Exit safely on SIGTERM by emitting "gui exit" from the main loops of
fe-text and fe-none rather than from the signal handler itself.

Based on feedback from Nei and dwfreed.

src/common.h

@@ -6,7 +6,7 @@
 #define IRSSI_GLOBAL_CONFIG "irssi.conf" /* config file name in /etc/ */
 #define IRSSI_HOME_CONFIG "config" /* config file name in ~/.irssi/ */
 
-#define IRSSI_ABI_VERSION 49
+#define IRSSI_ABI_VERSION 50
 
 #define DEFAULT_SERVER_ADD_PORT 6667
 #define DEFAULT_SERVER_ADD_TLS_PORT 6697

src/core/core.c

@@ -68,6 +68,7 @@ void wcwidth_wrapper_deinit(void);
 int irssi_gui;
 int irssi_init_finished;
 int sighup_received;
+int sigterm_received;
 time_t client_start_time;
 
 static char *irssi_dir, *irssi_config_file;
@@ -89,6 +90,11 @@ static void sig_hup(int signo)
 	sighup_received = TRUE;
 }
 
+static void sig_term(int signo)
+{
+	sigterm_received = TRUE;
+}
+
 static void read_settings(void)
 {
 	static int signals[] = {
@@ -113,8 +119,15 @@ static void read_settings(void)
 	sigaction(SIGHUP, &act, NULL);
 
 	for (n = 0; n < sizeof(signals)/sizeof(signals[0]); n++) {
-		act.sa_handler = find_substr(ignores, signames[n]) ?
+		if (find_substr(ignores, signames[n])) {
-			SIG_IGN : SIG_DFL;
+			act.sa_handler = SIG_IGN;
+		} else {
+			/* set default handlers */
+			if (signals[n] == SIGTERM)
+				act.sa_handler = sig_term;
+			else
+				act.sa_handler = SIG_DFL;
+		}
 		sigaction(signals[n], &act, NULL);
 	}
 

src/core/core.h

@@ -14,6 +14,7 @@
 extern int irssi_gui;
 extern int irssi_init_finished; /* TRUE after "irssi init finished" signal is sent */
 extern int sighup_received; /* TRUE after received SIGHUP. */
+extern int sigterm_received; /* TRUE after received SIGTERM. */
 extern time_t client_start_time;
 
 void core_preinit(const char *path);

src/core/settings.c

@@ -673,18 +673,6 @@ GSList *settings_get_sorted(void)
 	return list;
 }
 
-void sig_term(int n)
-{
-	/* if we get SIGTERM after this, just die instead of coming back here. */
-	signal(SIGTERM, SIG_DFL);
-
-	/* quit from all servers too.. */
-	signal_emit("command quit", 1, "");
-
-	/* and die */
-	raise(SIGTERM);
-}
-
 /* Yes, this is my own stupid checksum generator, some "real" algorithm
    would be nice but would just take more space without much real benefit */
 static unsigned int file_checksum(const char *fname)
@@ -805,8 +793,6 @@ static void init_configfile(void)
 		signal_emit("gui dialog", 2, "error", str);
                 g_free(str);
 	}
-
-	signal(SIGTERM, sig_term);
 }
 
 int settings_reread(const char *fname)

src/fe-none/irssi.c

@@ -29,10 +29,11 @@
 static GMainLoop *main_loop;
 static char *autoload_module;
 static int reload;
+static int quitting;
 
 static void sig_exit(void)
 {
-	g_main_loop_quit(main_loop);
+	quitting = TRUE;
 }
 
 static void sig_reload(void)
@@ -103,7 +104,14 @@ int main(int argc, char **argv)
 		reload = FALSE;
 		module_load(autoload_module, NULL);
 		main_loop = g_main_loop_new(NULL, TRUE);
-		g_main_loop_run(main_loop);
+		while (!quitting && !reload) {
+			if (sigterm_received) {
+				sigterm_received = FALSE;
+				signal_emit("gui exit", 0);
+			}
+
+			g_main_context_iteration(NULL, TRUE);
+		}
 		g_main_loop_unref(main_loop);
 	}
 	while (reload);

src/fe-text/irssi.c

@@ -331,6 +331,11 @@ int main(int argc, char **argv)
 	/* Does the same as g_main_run(main_loop), except we
 	   can call our dirty-checker after each iteration */
 	while (!quitting) {
+		if (sigterm_received) {
+			sigterm_received = FALSE;
+			signal_emit("gui exit", 0);
+		}
+
 		if (sighup_received) {
 			sighup_received = FALSE;