Added PancakeSchedulerGetNextExecutionTimeOffset()

Prevents race conditions caused by several calls to time() (might result in calculated offset -1)
pp3345 · Apr 11, 2014 · a30300c · a30300c
1 parent fc240d4
commit a30300c
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Showing 3 changed files with 14 additions and 1 deletion.
diff --git a/LinuxPoll/PancakeLinuxPoll.c b/LinuxPoll/PancakeLinuxPoll.c
@@ -267,7 +267,7 @@ static void PancakeLinuxPollWait() {
 		struct epoll_event events[32];
 		Int32 numEvents, i;
 
-		numEvents = epoll_wait(PancakeLinuxPollFD, events, 32, (PancakeSchedulerGetNextExecutionTime() - time(NULL)) * 1000);
+		numEvents = epoll_wait(PancakeLinuxPollFD, events, 32, PancakeSchedulerGetNextExecutionTimeOffset() * 1000);
 
 		if(UNEXPECTED(numEvents == -1)) {
 			if(PancakeDoShutdown) {

diff --git a/PancakeScheduler.c b/PancakeScheduler.c
@@ -79,6 +79,18 @@ PANCAKE_API inline UNative PancakeSchedulerGetNextExecutionTime() {
 	return events->time < time(NULL) ? time(NULL) : events->time;
 }
 
+PANCAKE_API inline UNative PancakeSchedulerGetNextExecutionTimeOffset() {
+	UNative now;
+
+	if(!events) {
+		return 86400;
+	}
+
+	now = time(NULL);
+
+	return events->time < now ? 0 : events->time - now;
+}
+
 PANCAKE_API inline UNative PancakeSchedulerGetNextScheduledTime() {
 	if(!events) {
 		return 0;

diff --git a/PancakeScheduler.h b/PancakeScheduler.h
@@ -17,6 +17,7 @@ typedef struct _PancakeSchedulerEvent {
 PANCAKE_API PancakeSchedulerEvent *PancakeSchedule(UNative time, PancakeSchedulerEventCallback callback, void *arg);
 PANCAKE_API inline void PancakeUnschedule(PancakeSchedulerEvent *event);
 PANCAKE_API inline UNative PancakeSchedulerGetNextExecutionTime(); /* returns >= time() */
+PANCAKE_API inline UNative PancakeSchedulerGetNextExecutionTimeOffset(); /* return >= 0 */
 PANCAKE_API inline UNative PancakeSchedulerGetNextScheduledTime(); /* returns actual scheduled time (can be < time()) */
 PANCAKE_API void PancakeSchedulerRun();