Simplify the public PowerObserver interface

atom/browser/api/atom_api_power_monitor.cc

@@ -24,14 +24,6 @@ PowerMonitor::~PowerMonitor() {
   base::PowerMonitor::Get()->RemoveObserver(this);
 }
 
-void PowerMonitor::BlockShutdown(mate::Arguments* args) {
-  atom::PowerObserver::BlockShutdown();
-}
-
-void PowerMonitor::UnblockShutdown(mate::Arguments* args) {
-  atom::PowerObserver::UnblockShutdown();
-}
-
 void PowerMonitor::OnPowerStateChange(bool on_battery_power) {
   if (on_battery_power)
     Emit("on-battery");
@@ -47,9 +39,11 @@ void PowerMonitor::OnResume() {
   Emit("resume");
 }
 
+#if defined(OS_LINUX)
 bool PowerMonitor::OnShutdown() {
   return Emit("shutdown");
 }
+#endif
 
 // static
 v8::Local<v8::Value> PowerMonitor::Create(v8::Isolate* isolate) {
@@ -67,9 +61,11 @@ v8::Local<v8::Value> PowerMonitor::Create(v8::Isolate* isolate) {
 void PowerMonitor::BuildPrototype(
     v8::Isolate* isolate, v8::Local<v8::FunctionTemplate> prototype) {
   prototype->SetClassName(mate::StringToV8(isolate, "PowerMonitor"));
+#if defined(OS_LINUX)
   mate::ObjectTemplateBuilder(isolate, prototype->PrototypeTemplate())
       .SetMethod("blockShutdown", &PowerMonitor::BlockShutdown)
       .SetMethod("unblockShutdown", &PowerMonitor::UnblockShutdown);
+#endif
 }
 
 }  // namespace api

atom/browser/api/atom_api_power_monitor.h

@@ -26,16 +26,15 @@ class PowerMonitor : public mate::TrackableObject<PowerMonitor>,
   explicit PowerMonitor(v8::Isolate* isolate);
   ~PowerMonitor() override;
 
-  void BlockShutdown(mate::Arguments* args);
-  void UnblockShutdown(mate::Arguments* args);
-
   // base::PowerObserver implementations:
   void OnPowerStateChange(bool on_battery_power) override;
   void OnSuspend() override;
   void OnResume() override;
 
+#if defined(OS_LINUX)
   // atom::PowerObserver
   bool OnShutdown() override;
+#endif
 
  private:
   DISALLOW_COPY_AND_ASSIGN(PowerMonitor);

atom/browser/lib/power_observer.h

@@ -18,19 +18,7 @@ namespace atom {
 #if defined(OS_LINUX)
 typedef PowerObserverLinux PowerObserver;
 #else
-class PowerObserver : public base::PowerObserver {
- public:
-  PowerObserver() {}
-  void BlockShutdown() {}
-  void UnblockShutdown() {}
-  // Notification that the system is rebooting or shutting down. If the
-  // implementation returns true, the PowerObserver instance should try to delay
-  // OS shutdown so the application can perform cleanup before exiting.
-  virtual bool OnShutdown() { return false; }
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(PowerObserver);
-};
+typedef base::PowerObserver PowerObserver;
 #endif  // defined(OS_LINUX)
 
 }  // namespace atom

atom/browser/lib/power_observer_linux.h

@@ -20,10 +20,12 @@ class PowerObserverLinux : public base::PowerObserver {
  public:
   PowerObserverLinux();
 
+ protected:
   void BlockSleep();
   void UnblockSleep();
   void BlockShutdown();
   void UnblockShutdown();
+
   virtual bool OnShutdown() { return false; }
 
  private:
@@ -41,6 +43,7 @@ class PowerObserverLinux : public base::PowerObserver {
   base::ScopedFD sleep_lock_;
   base::ScopedFD shutdown_lock_;
   base::WeakPtrFactory<PowerObserverLinux> weak_ptr_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(PowerObserverLinux);
 };
 

lib/browser/api/power-monitor.js

@@ -5,16 +5,19 @@ const {powerMonitor, PowerMonitor} = process.atomBinding('power_monitor')
 Object.setPrototypeOf(PowerMonitor.prototype, EventEmitter.prototype)
 EventEmitter.call(powerMonitor)
 
-powerMonitor.on('newListener', (event) => {
-  if (event === 'shutdown' && powerMonitor.listenerCount('shutdown') === 0) {
-    powerMonitor.blockShutdown()
-  }
-})
+// On Linux we need to call blockShutdown() to subscribe to shutdown event.
+if (process.platform === 'linux') {
+  powerMonitor.on('newListener', (event) => {
+    if (event === 'shutdown' && powerMonitor.listenerCount('shutdown') === 0) {
+      powerMonitor.blockShutdown()
+    }
+  })
 
-powerMonitor.on('removeListener', (event) => {
-  if (event === 'shutdown' && powerMonitor.listenerCount('shutdown') === 0) {
-    powerMonitor.unblockShutdown()
-  }
-})
+  powerMonitor.on('removeListener', (event) => {
+    if (event === 'shutdown' && powerMonitor.listenerCount('shutdown') === 0) {
+      powerMonitor.unblockShutdown()
+    }
+  })
+}
 
 module.exports = powerMonitor