michael@0: // Copyright (c) 2010 The Chromium Authors. All rights reserved.
michael@0: // Use of this source code is governed by a BSD-style license that can be
michael@0: // found in the LICENSE file.
michael@0: 
michael@0: #include "base/message_pump_android.h"
michael@0: 
michael@0: #include <fcntl.h>
michael@0: #include <math.h>
michael@0: 
michael@0: #include "base/eintr_wrapper.h"
michael@0: #include "base/lazy_instance.h"
michael@0: #include "base/logging.h"
michael@0: #include "base/platform_thread.h"
michael@0: 
michael@0: namespace mozilla {
michael@0: bool ProcessNextEvent();
michael@0: void NotifyEvent();
michael@0: }
michael@0: 
michael@0: namespace base {
michael@0: 
michael@0: MessagePumpForUI::MessagePumpForUI()
michael@0:   : state_(NULL)
michael@0:   , pump(*this)
michael@0: {
michael@0: }
michael@0: 
michael@0: MessagePumpForUI::~MessagePumpForUI() {
michael@0: }
michael@0: 
michael@0: MessagePumpAndroid::MessagePumpAndroid(MessagePumpForUI &aPump)
michael@0:   : pump(aPump)
michael@0: {
michael@0: }
michael@0: 
michael@0: MessagePumpAndroid::~MessagePumpAndroid()
michael@0: {
michael@0: }
michael@0: 
michael@0: void MessagePumpForUI::Run(Delegate* delegate) {
michael@0:   RunState state;
michael@0:   state.delegate = delegate;
michael@0:   state.should_quit = false;
michael@0:   state.run_depth = state_ ? state_->run_depth + 1 : 1;
michael@0:   // We really only do a single task for each iteration of the loop.  If we
michael@0:   // have done something, assume there is likely something more to do.  This
michael@0:   // will mean that we don't block on the message pump until there was nothing
michael@0:   // more to do.  We also set this to true to make sure not to block on the
michael@0:   // first iteration of the loop, so RunAllPending() works correctly.
michael@0:   state.more_work_is_plausible = true;
michael@0: 
michael@0:   RunState* previous_state = state_;
michael@0:   state_ = &state;
michael@0: 
michael@0:   // We run our own loop instead of using g_main_loop_quit in one of the
michael@0:   // callbacks.  This is so we only quit our own loops, and we don't quit
michael@0:   // nested loops run by others.  TODO(deanm): Is this what we want?
michael@0: 
michael@0:   while (!state_->should_quit) {
michael@0:     mozilla::ProcessNextEvent();
michael@0:     if (work_scheduled) {
michael@0:       work_scheduled = false;
michael@0:       HandleDispatch();
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   state_ = previous_state;
michael@0: }
michael@0: 
michael@0: void MessagePumpForUI::HandleDispatch() {
michael@0:   // We should only ever have a single message on the wakeup pipe, since we
michael@0:   // are only signaled when the queue went from empty to non-empty.  The qApp
michael@0:   // poll will tell us whether there was data, so this read shouldn't block.
michael@0:   if (state_->should_quit)
michael@0:     return;
michael@0: 
michael@0:   state_->more_work_is_plausible = false;
michael@0: 
michael@0:   if (state_->delegate->DoWork())
michael@0:     state_->more_work_is_plausible = true;
michael@0: 
michael@0:   if (state_->should_quit)
michael@0:     return;
michael@0: 
michael@0:   if (state_->delegate->DoDelayedWork(&delayed_work_time_))
michael@0:     state_->more_work_is_plausible = true;
michael@0:   if (state_->should_quit)
michael@0:     return;
michael@0: 
michael@0:   // Don't do idle work if we think there are more important things
michael@0:   // that we could be doing.
michael@0:   if (state_->more_work_is_plausible)
michael@0:     return;
michael@0: 
michael@0:   if (state_->delegate->DoIdleWork())
michael@0:     state_->more_work_is_plausible = true;
michael@0:   if (state_->should_quit)
michael@0:     return;
michael@0: }
michael@0: 
michael@0: void MessagePumpForUI::Quit() {
michael@0:   if (state_) {
michael@0:     state_->should_quit = true;
michael@0:   } else {
michael@0:     NOTREACHED() << "Quit called outside Run!";
michael@0:   }
michael@0: }
michael@0: 
michael@0: void MessagePumpForUI::ScheduleWork() {
michael@0:   // This can be called on any thread, so we don't want to touch any state
michael@0:   // variables as we would then need locks all over.  This ensures that if
michael@0:   // we are sleeping in a poll that we will wake up.
michael@0:   work_scheduled = true;
michael@0:   mozilla::NotifyEvent();
michael@0: }
michael@0: 
michael@0: void MessagePumpForUI::ScheduleDelayedWork(const TimeTicks& delayed_work_time) {
michael@0:   // We need to wake up the loop in case the poll timeout needs to be
michael@0:   // adjusted.  This will cause us to try to do work, but that's ok.
michael@0:   delayed_work_time_ = delayed_work_time;
michael@0:   ScheduleWork();
michael@0: }
michael@0: 
michael@0: }  // namespace base