* set_alarm() now correctly returns the time left for the currently active

alarm, or 0 if there isn't any.
* setitimer() now also sets the previous timer values correctly, so that
  alarm() and ualarm() now return the correct values as well - this fixes
  the test fork_9-1 failing at alarm().


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@18545 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/system/kernel/signal.c

@@ -493,11 +493,17 @@ alarm_event(timer *t)
 }
 
 
+/** Sets the alarm timer for the current thread. The timer fires at the
+ *	specified time in the future, periodically or just once, as determined
+ *	by \a mode.
+ *	\return the time left until a previous set alarm would have fired.
+ */
+
 bigtime_t
 set_alarm(bigtime_t time, uint32 mode)
 {
 	struct thread *thread = thread_get_current_thread();
-	bigtime_t rv = 0;
+	bigtime_t remainingTime = 0;
 
 	ASSERT(B_ONE_SHOT_RELATIVE_ALARM == B_ONE_SHOT_RELATIVE_TIMER);
 		// just to be sure no one changes the headers some day
@@ -505,14 +511,18 @@ set_alarm(bigtime_t time, uint32 mode)
 	TRACE(("set_alarm: thread = %p\n", thread));
 
 	if (thread->alarm.period)
-		rv = (bigtime_t)thread->alarm.entry.key - system_time();
+		remainingTime = (bigtime_t)thread->alarm.entry.key - system_time();
 
 	cancel_timer(&thread->alarm);
 
 	if (time != B_INFINITE_TIMEOUT)
 		add_timer(&thread->alarm, &alarm_event, time, mode);
+	else {
+		// this marks the alarm as canceled (for returning the remaining time)
+		thread->alarm.period = 0;
+	}
 
-	return rv;
+	return remainingTime;
 }
 
 

src/system/kernel/thread.c

@@ -209,6 +209,7 @@ create_thread_struct(const char *name, thread_id threadID)
 	thread->queue_next = NULL;
 	thread->priority = thread->next_priority = -1;
 	thread->args1 = NULL;  thread->args2 = NULL;
+	thread->alarm.period = 0;
 	thread->sig_pending = 0;
 	thread->sig_block_mask = 0;
 	memset(thread->sig_action, 0, 32 * sizeof(struct sigaction));

src/system/libroot/posix/sys/itimer.c

@@ -1,7 +1,7 @@
 /*
-** Copyright 2004, Axel Dörfler, [email protected]. All rights reserved.
+ * Copyright 2004-2006, Axel Dörfler, [email protected]. All rights reserved.
-** Distributed under the terms of the Haiku License.
+ * Distributed under the terms of the MIT License.
-*/
+ */
 
 
 #include <OS.h>
@@ -28,22 +28,22 @@ setitimer(int which, const struct itimerval *value, struct itimerval *oldValue)
 	// We probably need a better internal set_alarm() implementation to do this
 
 	bigtime_t interval = value->it_interval.tv_sec * USEC_PER_SECOND + value->it_interval.tv_usec;
+	bigtime_t remaining;
 	if (interval != 0)
-		set_alarm(interval, B_PERIODIC_ALARM);
+		remaining = set_alarm(interval, B_PERIODIC_ALARM);
 	else {
 		bigtime_t timeout = value->it_value.tv_sec * USEC_PER_SECOND + value->it_value.tv_usec;
 		if (timeout != 0)
-			set_alarm(timeout, B_ONE_SHOT_RELATIVE_ALARM);
+			remaining = set_alarm(timeout, B_ONE_SHOT_RELATIVE_ALARM);
 		else {
 			// cancel alarm
-			set_alarm(B_INFINITE_TIMEOUT, B_PERIODIC_ALARM);
+			remaining = set_alarm(B_INFINITE_TIMEOUT, B_PERIODIC_ALARM);
 		}
 	}
 
-	// whatever set_alarm() returns (not documented in the BeBook, and I haven't
+	// Record the time left of any previous itimer
-	// investigated this yet), maybe we can maintain the oldValue with it.
+	oldValue->it_value.tv_sec = remaining / USEC_PER_SECOND;
-
+	oldValue->it_value.tv_usec = remaining % USEC_PER_SECOND;
-	memset(oldValue, 0, sizeof(struct itimerval));
 
 	return 0;
 }