Move SystemMonitor to src/ui/base/system_monitor. Move HiResTimerManager to src/chrome/common.

BUG=none
TEST=none
TBR=brettw

Review URL: http://codereview.chromium.org/6361002


git-svn-id: svn://svn.chromium.org/chrome/trunk/src@71797 0039d316-1c4b-4281-b951-d872f2087c98

6 files changed, 473 insertions, 0 deletions

diff --git a/ui/base/system_monitor/system_monitor.cc b/ui/base/system_monitor/system_monitor.cc
new file mode 100644
index 0000000..80110cb
--- /dev/null
+++ b/ui/base/system_monitor/system_monitor.cc
@@ -0,0 +1,108 @@
+// Copyright (c) 2011 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 "ui/base/system_monitor/system_monitor.h"
+
+#include "base/logging.h"
+#include "base/message_loop.h"
+#include "base/time.h"
+
+namespace ui {
+
+static SystemMonitor* g_system_monitor = NULL;
+
+#if defined(ENABLE_BATTERY_MONITORING)
+// The amount of time (in ms) to wait before running the initial
+// battery check.
+static int kDelayedBatteryCheckMs = 10 * 1000;
+#endif  // defined(ENABLE_BATTERY_MONITORING)
+
+SystemMonitor::SystemMonitor()
+    : observer_list_(new ObserverListThreadSafe<PowerObserver>()),
+      battery_in_use_(false),
+      suspended_(false) {
+  DCHECK(!g_system_monitor);
+  g_system_monitor = this;
+
+  DCHECK(MessageLoop::current());
+#if defined(ENABLE_BATTERY_MONITORING)
+  delayed_battery_check_.Start(
+      base::TimeDelta::FromMilliseconds(kDelayedBatteryCheckMs), this,
+      &SystemMonitor::BatteryCheck);
+#endif  // defined(ENABLE_BATTERY_MONITORING)
+#if defined(OS_MACOSX)
+  PlatformInit();
+#endif
+}
+
+SystemMonitor::~SystemMonitor() {
+#if defined(OS_MACOSX)
+  PlatformDestroy();
+#endif
+  DCHECK_EQ(this, g_system_monitor);
+  g_system_monitor = NULL;
+}
+
+// static
+SystemMonitor* SystemMonitor::Get() {
+  return g_system_monitor;
+}
+
+void SystemMonitor::ProcessPowerMessage(PowerEvent event_id) {
+  // Suppress duplicate notifications.  Some platforms may
+  // send multiple notifications of the same event.
+  switch (event_id) {
+    case POWER_STATE_EVENT:
+      {
+        bool on_battery = IsBatteryPower();
+        if (on_battery != battery_in_use_) {
+          battery_in_use_ = on_battery;
+          NotifyPowerStateChange();
+        }
+      }
+      break;
+    case RESUME_EVENT:
+      if (suspended_) {
+        suspended_ = false;
+        NotifyResume();
+      }
+      break;
+    case SUSPEND_EVENT:
+      if (!suspended_) {
+        suspended_ = true;
+        NotifySuspend();
+      }
+      break;
+  }
+}
+
+void SystemMonitor::AddObserver(PowerObserver* obs) {
+  observer_list_->AddObserver(obs);
+}
+
+void SystemMonitor::RemoveObserver(PowerObserver* obs) {
+  observer_list_->RemoveObserver(obs);
+}
+
+void SystemMonitor::NotifyPowerStateChange() {
+  VLOG(1) << "PowerStateChange: " << (BatteryPower() ? "On" : "Off")
+          << " battery";
+  observer_list_->Notify(&PowerObserver::OnPowerStateChange, BatteryPower());
+}
+
+void SystemMonitor::NotifySuspend() {
+  VLOG(1) << "Power Suspending";
+  observer_list_->Notify(&PowerObserver::OnSuspend);
+}
+
+void SystemMonitor::NotifyResume() {
+  VLOG(1) << "Power Resuming";
+  observer_list_->Notify(&PowerObserver::OnResume);
+}
+
+void SystemMonitor::BatteryCheck() {
+  ProcessPowerMessage(SystemMonitor::POWER_STATE_EVENT);
+}
+
+}  // namespace ui
diff --git a/ui/base/system_monitor/system_monitor.h b/ui/base/system_monitor/system_monitor.h
new file mode 100644
index 0000000..b1e26cf
--- /dev/null
+++ b/ui/base/system_monitor/system_monitor.h
@@ -0,0 +1,143 @@
+// Copyright (c) 2011 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.
+
+#ifndef UI_BASE_SYSTEM_MONITOR_SYSTEM_MONITOR_H_
+#define UI_BASE_SYSTEM_MONITOR_SYSTEM_MONITOR_H_
+#pragma once
+
+#include "build/build_config.h"
+
+// Windows HiRes timers drain the battery faster so we need to know the battery
+// status.  This isn't true for other platforms.
+#if defined(OS_WIN)
+#define ENABLE_BATTERY_MONITORING 1
+#else
+#undef ENABLE_BATTERY_MONITORING
+#endif  // !OS_WIN
+
+#include "base/observer_list_threadsafe.h"
+#if defined(ENABLE_BATTERY_MONITORING)
+#include "base/timer.h"
+#endif  // defined(ENABLE_BATTERY_MONITORING)
+
+#if defined(OS_MACOSX)
+#ifdef __OBJC__
+@class SystemMonitorBridge;
+#else
+class SystemMonitorBridge;
+#endif
+#endif
+
+namespace ui {
+
+// Class for monitoring various system-related subsystems
+// such as power management, network status, etc.
+// TODO(mbelshe):  Add support beyond just power management.
+class SystemMonitor {
+ public:
+  // Normalized list of power events.
+  enum PowerEvent {
+    POWER_STATE_EVENT,  // The Power status of the system has changed.
+    SUSPEND_EVENT,      // The system is being suspended.
+    RESUME_EVENT        // The system is being resumed.
+  };
+
+  // Create SystemMonitor. Only one SystemMonitor instance per application
+  // is allowed.
+  SystemMonitor();
+  ~SystemMonitor();
+
+  // Get the application-wide SystemMonitor (if not present, returns NULL).
+  static SystemMonitor* Get();
+
+  //
+  // Power-related APIs
+  //
+
+  // Is the computer currently on battery power.
+  // Can be called on any thread.
+  bool BatteryPower() const {
+    // Using a lock here is not necessary for just a bool.
+    return battery_in_use_;
+  }
+
+  // Callbacks will be called on the thread which creates the SystemMonitor.
+  // During the callback, Add/RemoveObserver will block until the callbacks
+  // are finished. Observers should implement quick callback functions; if
+  // lengthy operations are needed, the observer should take care to invoke
+  // the operation on an appropriate thread.
+  class PowerObserver {
+   public:
+    // Notification of a change in power status of the computer, such
+    // as from switching between battery and A/C power.
+    virtual void OnPowerStateChange(bool on_battery_power) {}
+
+    // Notification that the system is suspending.
+    virtual void OnSuspend() {}
+
+    // Notification that the system is resuming.
+    virtual void OnResume() {}
+
+   protected:
+    virtual ~PowerObserver() {}
+  };
+
+  // Add a new observer.
+  // Can be called from any thread.
+  // Must not be called from within a notification callback.
+  void AddObserver(PowerObserver* obs);
+
+  // Remove an existing observer.
+  // Can be called from any thread.
+  // Must not be called from within a notification callback.
+  void RemoveObserver(PowerObserver* obs);
+
+#if defined(OS_WIN)
+  // Windows-specific handling of a WM_POWERBROADCAST message.
+  // Embedders of this API should hook their top-level window
+  // message loop and forward WM_POWERBROADCAST through this call.
+  void ProcessWmPowerBroadcastMessage(int event_id);
+#endif
+
+  // Cross-platform handling of a power event.
+  void ProcessPowerMessage(PowerEvent event_id);
+
+ private:
+#if defined(OS_MACOSX)
+  void PlatformInit();
+  void PlatformDestroy();
+#endif
+
+  // Platform-specific method to check whether the system is currently
+  // running on battery power.  Returns true if running on batteries,
+  // false otherwise.
+  bool IsBatteryPower();
+
+  // Checks the battery status and notifies observers if the battery
+  // status has changed.
+  void BatteryCheck();
+
+  // Functions to trigger notifications.
+  void NotifyPowerStateChange();
+  void NotifySuspend();
+  void NotifyResume();
+
+  scoped_refptr<ObserverListThreadSafe<PowerObserver> > observer_list_;
+  bool battery_in_use_;
+  bool suspended_;
+
+#if defined(ENABLE_BATTERY_MONITORING)
+  base::OneShotTimer<SystemMonitor> delayed_battery_check_;
+#endif
+
+#if defined(OS_MACOSX)
+  SystemMonitorBridge* system_monitor_bridge_;
+#endif
+
+  DISALLOW_COPY_AND_ASSIGN(SystemMonitor);
+};
+
+}  // namespace ui
+
+#endif  // UI_BASE_SYSTEM_MONITOR_SYSTEM_MONITOR_H_
diff --git a/ui/base/system_monitor/system_monitor_mac.mm b/ui/base/system_monitor/system_monitor_mac.mm
new file mode 100644
index 0000000..ffcb2a2
--- /dev/null
+++ b/ui/base/system_monitor/system_monitor_mac.mm
@@ -0,0 +1,67 @@
+// Copyright (c) 2011 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 "ui/base/system_monitor/system_monitor.h"
+
+#import <AppKit/AppKit.h>
+
+@interface SystemMonitorBridge : NSObject {
+ @private
+  ui::SystemMonitor* systemMonitor_;  // weak
+}
+
+- (id)initWithSystemMonitor:(ui::SystemMonitor*)monitor;
+- (void)computerDidSleep:(NSNotification*)notification;
+- (void)computerDidWake:(NSNotification*)notification;
+
+@end
+
+@implementation SystemMonitorBridge
+
+- (id)initWithSystemMonitor:(ui::SystemMonitor*)monitor {
+  self = [super init];
+  if (self) {
+    systemMonitor_ = monitor;
+
+    // See QA1340
+    // <http://developer.apple.com/library/mac/#qa/qa2004/qa1340.html> for more
+    // details.
+    [[[NSWorkspace sharedWorkspace] notificationCenter]
+        addObserver:self
+           selector:@selector(computerDidSleep:)
+               name:NSWorkspaceWillSleepNotification
+             object:nil];
+    [[[NSWorkspace sharedWorkspace] notificationCenter]
+        addObserver:self
+           selector:@selector(computerDidWake:)
+               name:NSWorkspaceDidWakeNotification
+             object:nil];
+  }
+  return self;
+}
+
+- (void)dealloc {
+  [[[NSWorkspace sharedWorkspace] notificationCenter]
+      removeObserver:self];
+  [super dealloc];
+}
+
+- (void)computerDidSleep:(NSNotification*)notification {
+  systemMonitor_->ProcessPowerMessage(ui::SystemMonitor::SUSPEND_EVENT);
+}
+
+- (void)computerDidWake:(NSNotification*)notification {
+  systemMonitor_->ProcessPowerMessage(ui::SystemMonitor::RESUME_EVENT);
+}
+
+@end
+
+void ui::SystemMonitor::PlatformInit() {
+  system_monitor_bridge_ =
+      [[SystemMonitorBridge alloc] initWithSystemMonitor:this];
+}
+
+void ui::SystemMonitor::PlatformDestroy() {
+  [system_monitor_bridge_ release];
+}
diff --git a/ui/base/system_monitor/system_monitor_posix.cc b/ui/base/system_monitor/system_monitor_posix.cc
new file mode 100644
index 0000000..ddd0fe0
--- /dev/null
+++ b/ui/base/system_monitor/system_monitor_posix.cc
@@ -0,0 +1,14 @@
+// Copyright (c) 2011 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 "ui/base/system_monitor/system_monitor.h"
+
+namespace ui {
+
+bool SystemMonitor::IsBatteryPower() {
+  NOTIMPLEMENTED();
+  return false;
+}
+
+}  // namespace ui
diff --git a/ui/base/system_monitor/system_monitor_unittest.cc b/ui/base/system_monitor/system_monitor_unittest.cc
new file mode 100644
index 0000000..28b2cbf
--- /dev/null
+++ b/ui/base/system_monitor/system_monitor_unittest.cc
@@ -0,0 +1,91 @@
+// Copyright (c) 2011 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 "ui/base/system_monitor/system_monitor.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace ui {
+
+class PowerTest : public SystemMonitor::PowerObserver {
+ public:
+  PowerTest()
+      : battery_(false),
+        power_state_changes_(0),
+        suspends_(0),
+        resumes_(0) {
+  }
+
+  // PowerObserver callbacks.
+  void OnPowerStateChange(bool on_battery_power) {
+    power_state_changes_++;
+  }
+
+  void OnSuspend() {
+    suspends_++;
+  }
+
+  void OnResume() {
+    resumes_++;
+  }
+
+  // Test status counts.
+  bool battery() { return battery_; }
+  int power_state_changes() { return power_state_changes_; }
+  int suspends() { return suspends_; }
+  int resumes() { return resumes_; }
+
+ private:
+  bool battery_;   // Do we currently think we're on battery power.
+  int power_state_changes_;  // Count of OnPowerStateChange notifications.
+  int suspends_;  // Count of OnSuspend notifications.
+  int resumes_;  // Count of OnResume notifications.
+};
+
+TEST(SystemMonitor, PowerNotifications) {
+  const int kObservers = 5;
+
+  // Initialize a message loop for this to run on.
+  MessageLoop loop;
+  // Initialize time() since it registers as a SystemMonitor observer.
+  base::Time now = base::Time::Now();
+
+  SystemMonitor system_monitor;
+  PowerTest test[kObservers];
+  for (int index = 0; index < kObservers; ++index)
+    system_monitor.AddObserver(&test[index]);
+
+  // Send a bunch of power changes.  Since the battery power hasn't
+  // actually changed, we shouldn't get notifications.
+  for (int index = 0; index < 5; index++) {
+    system_monitor.ProcessPowerMessage(SystemMonitor::POWER_STATE_EVENT);
+    EXPECT_EQ(test[0].power_state_changes(), 0);
+  }
+
+  // Sending resume when not suspended should have no effect.
+  system_monitor.ProcessPowerMessage(SystemMonitor::RESUME_EVENT);
+  loop.RunAllPending();
+  EXPECT_EQ(test[0].resumes(), 0);
+
+  // Pretend we suspended.
+  system_monitor.ProcessPowerMessage(SystemMonitor::SUSPEND_EVENT);
+  loop.RunAllPending();
+  EXPECT_EQ(test[0].suspends(), 1);
+
+  // Send a second suspend notification.  This should be suppressed.
+  system_monitor.ProcessPowerMessage(SystemMonitor::SUSPEND_EVENT);
+  loop.RunAllPending();
+  EXPECT_EQ(test[0].suspends(), 1);
+
+  // Pretend we were awakened.
+  system_monitor.ProcessPowerMessage(SystemMonitor::RESUME_EVENT);
+  loop.RunAllPending();
+  EXPECT_EQ(test[0].resumes(), 1);
+
+  // Send a duplicate resume notification.  This should be suppressed.
+  system_monitor.ProcessPowerMessage(SystemMonitor::RESUME_EVENT);
+  loop.RunAllPending();
+  EXPECT_EQ(test[0].resumes(), 1);
+}
+
+}  // namespace ui
diff --git a/ui/base/system_monitor/system_monitor_win.cc b/ui/base/system_monitor/system_monitor_win.cc
new file mode 100644
index 0000000..df8aabf
--- /dev/null
+++ b/ui/base/system_monitor/system_monitor_win.cc
@@ -0,0 +1,50 @@
+// Copyright (c) 2011 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 "ui/base/system_monitor/system_monitor.h"
+
+namespace ui {
+
+void SystemMonitor::ProcessWmPowerBroadcastMessage(int event_id) {
+  PowerEvent power_event;
+  switch (event_id) {
+    case PBT_APMPOWERSTATUSCHANGE:  // The power status changed.
+      power_event = POWER_STATE_EVENT;
+      break;
+    case PBT_APMRESUMEAUTOMATIC:  // Resume from suspend.
+    //case PBT_APMRESUMESUSPEND:  // User-initiated resume from suspend.
+                                  // We don't notify for this latter event
+                                  // because if it occurs it is always sent as a
+                                  // second event after PBT_APMRESUMEAUTOMATIC.
+      power_event = RESUME_EVENT;
+      break;
+    case PBT_APMSUSPEND:  // System has been suspended.
+      power_event = SUSPEND_EVENT;
+      break;
+    default:
+      return;
+
+    // Other Power Events:
+    // PBT_APMBATTERYLOW - removed in Vista.
+    // PBT_APMOEMEVENT - removed in Vista.
+    // PBT_APMQUERYSUSPEND - removed in Vista.
+    // PBT_APMQUERYSUSPENDFAILED - removed in Vista.
+    // PBT_APMRESUMECRITICAL - removed in Vista.
+    // PBT_POWERSETTINGCHANGE - user changed the power settings.
+  }
+  ProcessPowerMessage(power_event);
+}
+
+// Function to query the system to see if it is currently running on
+// battery power.  Returns true if running on battery.
+bool SystemMonitor::IsBatteryPower() {
+  SYSTEM_POWER_STATUS status;
+  if (!GetSystemPowerStatus(&status)) {
+    LOG(ERROR) << "GetSystemPowerStatus failed: " << GetLastError();
+    return false;
+  }
+  return (status.ACLineStatus == 0);
+}
+
+}  // namespace ui