Source code
Revision control
Copy as Markdown
Other Tools
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
// Copyright (c) 2010 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_android.h"
#include <fcntl.h>
#include <math.h>
#include "base/eintr_wrapper.h"
#include "base/logging.h"
#include "base/platform_thread.h"
namespace mozilla {
bool ProcessNextEvent();
void NotifyEvent();
} // namespace mozilla
namespace base {
MessagePumpForUI::MessagePumpForUI() : state_(NULL) {}
MessagePumpForUI::~MessagePumpForUI() {}
void MessagePumpForUI::Run(Delegate* delegate) {
RunState state;
state.delegate = delegate;
state.should_quit = false;
state.run_depth = state_ ? state_->run_depth + 1 : 1;
// We really only do a single task for each iteration of the loop. If we
// have done something, assume there is likely something more to do. This
// will mean that we don't block on the message pump until there was nothing
// more to do. We also set this to true to make sure not to block on the
// first iteration of the loop, so RunAllPending() works correctly.
state.more_work_is_plausible = true;
RunState* previous_state = state_;
state_ = &state;
// We run our own loop instead of using g_main_loop_quit in one of the
// callbacks. This is so we only quit our own loops, and we don't quit
// nested loops run by others. TODO(deanm): Is this what we want?
while (!state_->should_quit) {
mozilla::ProcessNextEvent();
if (work_scheduled) {
work_scheduled = false;
HandleDispatch();
}
}
state_ = previous_state;
}
void MessagePumpForUI::HandleDispatch() {
// We should only ever have a single message on the wakeup pipe, since we
// are only signaled when the queue went from empty to non-empty. The qApp
// poll will tell us whether there was data, so this read shouldn't block.
if (state_->should_quit) return;
state_->more_work_is_plausible = false;
if (state_->delegate->DoWork()) state_->more_work_is_plausible = true;
if (state_->should_quit) return;
if (state_->delegate->DoDelayedWork(&delayed_work_time_))
state_->more_work_is_plausible = true;
if (state_->should_quit) return;
// Don't do idle work if we think there are more important things
// that we could be doing.
if (state_->more_work_is_plausible) return;
if (state_->delegate->DoIdleWork()) state_->more_work_is_plausible = true;
if (state_->should_quit) return;
}
void MessagePumpForUI::Quit() {
if (state_) {
state_->should_quit = true;
} else {
NOTREACHED() << "Quit called outside Run!";
}
}
void MessagePumpForUI::ScheduleWork() {
// This can be called on any thread, so we don't want to touch any state
// variables as we would then need locks all over. This ensures that if
// we are sleeping in a poll that we will wake up.
work_scheduled = true;
mozilla::NotifyEvent();
}
void MessagePumpForUI::ScheduleDelayedWork(const TimeTicks& delayed_work_time) {
// We need to wake up the loop in case the poll timeout needs to be
// adjusted. This will cause us to try to do work, but that's ok.
delayed_work_time_ = delayed_work_time;
ScheduleWork();
}
} // namespace base