1 files changed, 155 insertions, 0 deletions
diff --git a/common/core/Timer.cxx b/common/core/Timer.cxx
new file mode 100644
index 00000000..77e98daf
--- /dev/null
+++ b/common/core/Timer.cxx
@@ -0,0 +1,155 @@
+/* Copyright (C) 2002-2005 RealVNC Ltd.  All Rights Reserved.
+ * Copyright 2016-2024 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
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ * 
+ * This software is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this software; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,
+ * USA.
+ */
+
+// -=- Timer.cxx
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <sys/time.h>
+
+#include <algorithm>
+
+#include <core/LogWriter.h>
+#include <core/Timer.h>
+#include <core/time.h>
+
+using namespace core;
+
+#ifndef __NO_DEFINE_VLOG__
+static LogWriter vlog("Timer");
+#endif
+
+std::list<Timer*> Timer::pending;
+
+int Timer::checkTimeouts() {
+  timeval start;
+
+  if (pending.empty())
+    return -1;
+
+  gettimeofday(&start, nullptr);
+  while (pending.front()->isBefore(start)) {
+    Timer* timer;
+
+    timer = pending.front();
+    pending.pop_front();
+
+    timer->lastDueTime = timer->dueTime;
+    timer->cb->handleTimeout(timer);
+
+    if (pending.empty())
+      return -1;
+  }
+  return getNextTimeout();
+}
+
+int Timer::getNextTimeout() {
+  timeval now;
+  gettimeofday(&now, nullptr);
+
+  if (pending.empty())
+    return -1;
+
+  int toWait = pending.front()->getRemainingMs();
+
+  if (toWait > pending.front()->timeoutMs) {
+    if (toWait - pending.front()->timeoutMs < 1000) {
+      vlog.info("gettimeofday is broken...");
+      return toWait;
+    }
+    // Time has jumped backwards!
+    vlog.info("Time has moved backwards!");
+    pending.front()->dueTime = now;
+    toWait = 0;
+  }
+
+  return toWait;
+}
+
+void Timer::insertTimer(Timer* t) {
+  std::list<Timer*>::iterator i;
+  for (i=pending.begin(); i!=pending.end(); i++) {
+    if (t->isBefore((*i)->dueTime)) {
+      pending.insert(i, t);
+      return;
+    }
+  }
+  pending.push_back(t);
+}
+
+void Timer::start(int timeoutMs_) {
+  timeval now;
+  gettimeofday(&now, nullptr);
+  stop();
+  timeoutMs = timeoutMs_;
+  dueTime = addMillis(now, timeoutMs);
+  insertTimer(this);
+}
+
+void Timer::repeat(int timeoutMs_) {
+  timeval now;
+
+  gettimeofday(&now, nullptr);
+
+  if (isStarted()) {
+    vlog.error("Incorrectly repeating already running timer");
+    stop();
+  }
+
+  if (msBetween(&lastDueTime, &dueTime) != 0)
+    vlog.error("Timer incorrectly modified whilst repeating");
+
+  if (timeoutMs_ != -1)
+    timeoutMs = timeoutMs_;
+
+  dueTime = addMillis(lastDueTime, timeoutMs);
+  if (isBefore(now)) {
+    // Time has jumped forwards, or we're not getting enough
+    // CPU time for the timers
+    dueTime = now;
+  }
+
+  insertTimer(this);
+}
+
+void Timer::stop() {
+  pending.remove(this);
+}
+
+bool Timer::isStarted() {
+  return std::find(pending.begin(), pending.end(),
+                   this) != pending.end();
+}
+
+int Timer::getTimeoutMs() {
+  return timeoutMs;
+}
+
+int Timer::getRemainingMs() {
+  return msUntil(&dueTime);
+}
+
+bool Timer::isBefore(timeval other) {
+  return (dueTime.tv_sec < other.tv_sec) ||
+    ((dueTime.tv_sec == other.tv_sec) &&
+     (dueTime.tv_usec < other.tv_usec));
+}