Index: telemetry/telemetry/internal/util/repeating_timer.py |
diff --git a/telemetry/telemetry/internal/util/repeating_timer.py b/telemetry/telemetry/internal/util/repeating_timer.py |
new file mode 100644 |
index 0000000000000000000000000000000000000000..46211427587e0a4efe9528b668abf0bb5efd95d2 |
--- /dev/null |
+++ b/telemetry/telemetry/internal/util/repeating_timer.py |
@@ -0,0 +1,46 @@ |
+# Copyright 2017 The Chromium Authors. All rights reserved. |
+# Use of this source code is governed by a BSD-style license that can be |
+# found in the LICENSE file. |
+ |
+import threading |
+import time |
+ |
+class RepeatingTimer(object): |
+ """A simple repeating timer.""" |
+ |
+ def __init__(self, target, interval_s): |
+ """Create a timer object which will repeatedly run the target function |
+ with the specified interval. Interval should be specified in seconds. |
+ """ |
+ self._target = target |
+ self._interval = interval_s |
+ self._stop = threading.Event() |
+ self._stop.set() |
+ self._timer_thread = None |
+ |
+ def _BackgroundThread(self): |
+ target_time = time.time() + self._interval |
+ while not self._stop.wait(max(0, target_time - time.time())): |
+ target_time = target_time + self._interval |
+ self._target() |
+ |
+ def Start(self): |
+ """Start the timer. The target function will be called at regular intervals |
+ after the given interval elapses. The timer may be stopped and restarted. |
+ This must not be called if the timer is already running (Stop should be |
+ called to stop it first). |
+ """ |
+ # start new timer thread |
+ self._stop.clear() |
+ self._timer_thread = threading.Thread(target=self._BackgroundThread) |
+ self._timer_thread.start() |
+ |
+ def Stop(self): |
+ """Stop the timer and block until it has stopped. |
+ The timer must have been started before calling Stop.""" |
+ self._stop.set() |
+ self._timer_thread.join() |
+ |
+ def IsRunning(self): |
+ """Return true if the timer is currently running.""" |
+ return not self._stop.is_set() |