Don't make SIGINT kill a background process; don't call printf from a signal-handler; use sigaction instead of signal

src/main.c

@@ -1357,13 +1357,23 @@ void UTCToLocal(int utcdate, int utctime, int *locdate, int *loctime)
 /* command-line flag is supplied.			       */
 /*							       */
 /***************************************************************/
+static sig_atomic_t got_sigint = 0;
 
-void SigIntHandler(int d)
+void
+SigIntHandler(int d)
 {
     UNUSED(d);
-    signal(SIGINT, SigIntHandler);
-    GotSigInt();
-    exit(0);
+    got_sigint = 1;
+}
+
+int
+GotSigInt(void)
+{
+    if (got_sigint) {
+        got_sigint = 0;
+        return 1;
+    }
+    return 0;
 }
 
 void

src/protos.h

@@ -143,7 +143,7 @@ int MoonPhase (int date, int time);
 void HuntPhase (int startdate, int starttim, int phas, int *date, int *time);
 int CompareRems (int dat1, int tim1, int prio1, int dat2, int tim2, int prio2, int bydate, int bytime, int byprio, int untimed_first);
 void SigIntHandler (int d);
-void GotSigInt (void);
+int GotSigInt (void);
 void PurgeEchoLine(char const *fmt, ...);
 void FreeTrig(Trigger *t);
 void AppendTag(DynamicBuffer *buf, char const *s);

src/queue.c

@@ -59,6 +59,7 @@ static QueuedRem *FindNextReminder (void);
 static int CalculateNextTimeUsingSched (QueuedRem *q);
 static void DaemonWait (struct timeval *sleep_tv);
 static void reread (void);
+static void PrintQueue(void);
 
 /***************************************************************/
 /*                                                             */
@@ -123,6 +124,7 @@ void HandleQueuedReminders(void)
     Trigger trig;
     struct timeval tv;
     struct timeval sleep_tv;
+    struct sigaction sa;
 
     /* Suppress the BANNER from being issued */
     NumTriggered = 1;
@@ -161,7 +163,11 @@ void HandleQueuedReminders(void)
 	q = q->next;
     }
 
-    if (!DontFork || Daemon) signal(SIGINT, SigIntHandler);
+    if (!DontFork || Daemon) {
+        sa.sa_handler = SigIntHandler;
+        sa.sa_flags = 0;
+        (void) sigaction(SIGINT, &sa, NULL);
+    }
 
     /* Sit in a loop, issuing reminders when necessary */
     while(1) {
@@ -205,6 +211,10 @@ void HandleQueuedReminders(void)
 		sleep(SleepTime);
             }
 
+            if (GotSigInt()) {
+                PrintQueue();
+            }
+
 	    /* If not in daemon mode and day has rolled around,
 	       exit -- not much we can do. */
 	    if (!Daemon) {
@@ -337,13 +347,13 @@ static QueuedRem *FindNextReminder(void)
 
 /***************************************************************/
 /*                                                             */
-/* GotSigInt						       */
+/* PrintQueue						       */
 /*                                                             */
-/* Split out what's done on a SIGINT from the SIGINT Handler.  */
-/* This will be necessary for OS/2 multithreaded.	       */
+/* For debugging: Print queue contents to STDOUT               */
 /*                                                             */
 /***************************************************************/
-void GotSigInt(void)
+static
+void PrintQueue(void)
 {
     QueuedRem *q = QueueHead;