Index: base/message_pump_libevent.cc |
=================================================================== |
--- base/message_pump_libevent.cc (revision 0) |
+++ base/message_pump_libevent.cc (revision 0) |
@@ -0,0 +1,130 @@ |
+// Copyright (c) 2006-2008 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. |
+ |
+#include "base/message_pump_libevent.h" |
+#include "base/logging.h" |
+#include "base/time.h" |
+ |
+#include "third_party/libevent/event.h" |
+ |
+// Called if a byte is received on the wakeup pipe |
+extern "C" void MessagePumpLibevent_wakeup(int socket, short flags, void *context) { |
+ base::MessagePumpLibevent* that = static_cast<base::MessagePumpLibevent*>(context); |
+ DCHECK(that->wakeup_pipe_gazouta_ == socket); |
+ |
+ // remove and discard the wakeup byte |
+ char buf; |
+ int nread = read(socket, &buf, 1); |
+ DCHECK(nread == 1); |
+ // tell libevent to break out of inner loop |
+ event_base_loopbreak(that->evbase_); |
+} |
+ |
+namespace base { |
+ |
+MessagePumpLibevent::MessagePumpLibevent() |
+ : keep_running_(true) { |
+ evbase_ = event_base_new(); |
+ wakeup_event_ = new event; |
+ |
+ // Dang, too much real work in the constructor. |
+ int fds[2]; |
+ int err = pipe(fds); |
+ DCHECK(!err); |
+ if (err) { |
+ wakeup_pipe_gazinta_ = -1; |
+ wakeup_pipe_gazouta_ = -1; |
+ memset(wakeup_event_, 0, sizeof(*wakeup_event_)); |
+ } else { |
+ wakeup_pipe_gazouta_ = fds[0]; |
+ wakeup_pipe_gazinta_ = fds[1]; |
+ event_set(wakeup_event_, wakeup_pipe_gazouta_, |
+ EV_READ | EV_PERSIST, MessagePumpLibevent_wakeup, this); |
+ event_base_set(evbase_, wakeup_event_); |
+ |
+ if (event_add(wakeup_event_, 0) == -1) { |
+ DCHECK(0); |
+ // Did I mention this was too much real work in the constructor? |
+ } |
+ } |
+} |
+ |
+MessagePumpLibevent::~MessagePumpLibevent() { |
+ DCHECK(wakeup_event_); |
+ DCHECK(evbase_); |
+ event_del(wakeup_event_); |
+ delete wakeup_event_; |
+ wakeup_event_ = 0; |
+ event_base_free(evbase_); |
+ evbase_ = 0; |
+} |
+ |
+void MessagePumpLibevent::Run(Delegate* delegate) { |
+ DCHECK(keep_running_) << "Quit must have been called outside of Run!"; |
+ |
+ for (;;) { |
+ bool did_work = delegate->DoWork(); |
+ if (!keep_running_) |
+ break; |
+ |
+ did_work |= delegate->DoDelayedWork(&delayed_work_time_); |
+ if (!keep_running_) |
+ break; |
+ |
+ if (did_work) |
+ continue; |
+ |
+ did_work = delegate->DoIdleWork(); |
+ if (!keep_running_) |
+ break; |
+ |
+ if (did_work) |
+ continue; |
+ |
+ // 50 wakeups per second sucks, but without this, tests take a long time or hang. |
+ int poll_ms = 20; |
+ if (!delayed_work_time_.is_null()) { |
+ TimeDelta delay = delayed_work_time_ - Time::Now(); |
+ if (delay > TimeDelta()) { |
+ int delay_ms = delay.InMilliseconds(); |
+ if (delay_ms < poll_ms) |
+ poll_ms = delay_ms; |
+ } else { |
+ // It looks like delayed_work_time_ indicates a time in the past, so we |
+ // need to call DoDelayedWork now. |
+ delayed_work_time_ = Time(); |
+ } |
+ } |
+ struct timeval poll_tv; |
+ poll_tv.tv_sec = 0; |
+ poll_tv.tv_usec = poll_ms * 1000; |
+ event_base_loopexit(evbase_, &poll_tv); |
+ event_base_loop(evbase_, 0); |
+ } |
+ |
+ keep_running_ = true; |
+} |
+ |
+void MessagePumpLibevent::Quit() { |
+ ScheduleWork(); |
+ keep_running_ = false; |
+} |
+ |
+void MessagePumpLibevent::ScheduleWork() { |
+ // This can be called on any thread. |
+ // Tell libevent (in a threadsafe way) that it should break out of its loop. |
+ char buf = 0; |
+ int nwrite = write(wakeup_pipe_gazinta_, &buf, 1); |
+ DCHECK(nwrite == 1); |
+} |
+ |
+void MessagePumpLibevent::ScheduleDelayedWork(const Time& delayed_work_time) { |
+ // We know that we can't be blocked on Wait right now since this method can |
+ // only be called on the same thread as Run, so we only need to update our |
+ // record of how long to sleep when we do sleep. |
+ delayed_work_time_ = delayed_work_time; |
+} |
+ |
+} // namespace base |
+ |