Better handling of slow timers
Make sure the code deals more gracefully with timers that take a
long time to execute, and therefore might miss their deadlines.
diff --git a/common/rfb/Timer.cxx b/common/rfb/Timer.cxx
index 676f24e..efae36e 100644
--- a/common/rfb/Timer.cxx
+++ b/common/rfb/Timer.cxx
@@ -1,4 +1,5 @@
/* Copyright (C) 2002-2005 RealVNC Ltd. All Rights Reserved.
+ * Copyright 2016 Pierre Ossman for Cendio AB
*
* This is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -58,20 +59,35 @@
std::list<Timer*> Timer::pending;
int Timer::checkTimeouts() {
+ timeval start;
+
if (pending.empty())
return 0;
- timeval now;
- gettimeofday(&now, 0);
- while (pending.front()->isBefore(now)) {
- Timer* timer = pending.front();
+
+ gettimeofday(&start, 0);
+ while (pending.front()->isBefore(start)) {
+ Timer* timer;
+ timeval before;
+
+ timer = pending.front();
pending.pop_front();
+
+ gettimeofday(&before, 0);
if (timer->cb->handleTimeout(timer)) {
+ timeval now;
+
+ gettimeofday(&now, 0);
+
timer->dueTime = addMillis(timer->dueTime, timer->timeoutMs);
if (timer->isBefore(now)) {
- // Time has jumped forwards!
- vlog.info("time has moved forwards!");
- timer->dueTime = addMillis(now, timer->timeoutMs);
+ // Time has jumped forwards, or we're not getting enough
+ // CPU time for the timers
+
+ timer->dueTime = addMillis(before, timer->timeoutMs);
+ if (timer->isBefore(now))
+ timer->dueTime = now;
}
+
insertTimer(timer);
} else if (pending.empty()) {
return 0;