Bug 1756635 - Make GTK wake lock lifetime more similar to other desktop platforms. r=stransky

This matches what macOS and Windows do, and should clean up the wake
lock stuff early enough to not hit this issue.

Differential Revision: https://phabricator.services.mozilla.com/D194376

widget/gtk/WakeLockListener.cpp

@@ -24,7 +24,6 @@
 #if defined(MOZ_WAYLAND)
 #  include "mozilla/widget/nsWaylandDisplay.h"
 #  include "nsWindow.h"
-#  include "mozilla/dom/power/PowerManagerService.h"
 #endif
 
 #ifdef MOZ_ENABLE_DBUS
@@ -48,8 +47,6 @@ using namespace mozilla::widget;
 
 NS_IMPL_ISUPPORTS(WakeLockListener, nsIDOMMozWakeLockListener)
 
-StaticRefPtr<WakeLockListener> WakeLockListener::sSingleton;
-
 #define WAKE_LOCK_LOG(str, ...)                        \
   MOZ_LOG(gLinuxWakeLockLog, mozilla::LogLevel::Debug, \
           ("[%p] " str, this, ##__VA_ARGS__))
@@ -716,21 +713,6 @@ bool WakeLockTopic::SwitchToNextWakeLockType() {
   return false;
 }
 
-/* static */
-WakeLockListener* WakeLockListener::GetSingleton(bool aCreate) {
-  if (!sSingleton && aCreate) {
-    sSingleton = new WakeLockListener();
-  }
-  return sSingleton;
-}
-
-/* static */
-void WakeLockListener::Shutdown() {
-  MOZ_LOG(gLinuxWakeLockLog, mozilla::LogLevel::Debug,
-          ("WakeLockListener::Shutdown()"));
-  sSingleton = nullptr;
-}
-
 nsresult WakeLockListener::Callback(const nsAString& topic,
                                     const nsAString& state) {
   if (!topic.Equals(u"screen"_ns) && !topic.Equals(u"video-playing"_ns) &&

widget/gtk/WakeLockListener.h

@@ -8,18 +8,11 @@
 #ifndef __WakeLockListener_h__
 #define __WakeLockListener_h__
 
-#include <unistd.h>
-
-#include "mozilla/StaticPtr.h"
 #include "nsHashKeys.h"
 #include "nsRefPtrHashtable.h"
 
 #include "nsIDOMWakeLockListener.h"
 
-#ifdef MOZ_ENABLE_DBUS
-#  include "mozilla/DBusHelpers.h"
-#endif
-
 class WakeLockTopic;
 
 /**
@@ -30,17 +23,11 @@ class WakeLockListener final : public nsIDOMMozWakeLockListener {
  public:
   NS_DECL_ISUPPORTS;
 
-  static WakeLockListener* GetSingleton(bool aCreate = true);
+  nsresult Callback(const nsAString& topic, const nsAString& state) override;
-  static void Shutdown();
-
-  virtual nsresult Callback(const nsAString& topic,
-                            const nsAString& state) override;
 
  private:
   ~WakeLockListener() = default;
 
-  static mozilla::StaticRefPtr<WakeLockListener> sSingleton;
-
   // Map of topic names to |WakeLockTopic|s.
   // We assume a small, finite-sized set of topics.
   nsRefPtrHashtable<nsStringHashKey, WakeLockTopic> mTopics;

widget/gtk/nsAppShell.cpp

@@ -267,6 +267,29 @@ void nsAppShell::StartDBusListening() {
       reinterpret_cast<GAsyncReadyCallback>(DBusConnectClientResponse), this);
 }
 
+mozilla::StaticRefPtr<WakeLockListener> sWakeLockListener;
+
+static void AddScreenWakeLockListener() {
+  nsCOMPtr<nsIPowerManagerService> powerManager =
+      do_GetService(POWERMANAGERSERVICE_CONTRACTID);
+  if (powerManager) {
+    sWakeLockListener = new WakeLockListener();
+    powerManager->AddWakeLockListener(sWakeLockListener);
+  } else {
+    NS_WARNING(
+        "Failed to retrieve PowerManagerService, wakelocks will be broken!");
+  }
+}
+
+static void RemoveScreenWakeLockListener() {
+  nsCOMPtr<nsIPowerManagerService> powerManager =
+      do_GetService(POWERMANAGERSERVICE_CONTRACTID);
+  if (powerManager) {
+    powerManager->RemoveWakeLockListener(sWakeLockListener);
+    sWakeLockListener = nullptr;
+  }
+}
+
 void nsAppShell::StopDBusListening() {
   if (mLogin1Proxy) {
     g_signal_handlers_disconnect_matched(mLogin1Proxy, G_SIGNAL_MATCH_DATA, 0,
@@ -293,22 +316,11 @@ void nsAppShell::StopDBusListening() {
 nsresult nsAppShell::Init() {
   mozilla::hal::Init();
 
-  if (XRE_IsParentProcess()) {
-    nsCOMPtr<nsIPowerManagerService> powerManagerService =
-        do_GetService(POWERMANAGERSERVICE_CONTRACTID);
-
-    if (powerManagerService) {
-      powerManagerService->AddWakeLockListener(
-          WakeLockListener::GetSingleton());
-    } else {
-      NS_WARNING(
-          "Failed to retrieve PowerManagerService, wakelocks will be broken!");
-    }
-
 #ifdef MOZ_ENABLE_DBUS
+  if (XRE_IsParentProcess()) {
     StartDBusListening();
-#endif
   }
+#endif
 
   if (!sPollFunc) {
     sPollFunc = g_main_context_get_poll_func(nullptr);
@@ -408,6 +420,19 @@ failed:
   return NS_ERROR_FAILURE;
 }
 
+NS_IMETHODIMP nsAppShell::Run() {
+  if (XRE_IsParentProcess()) {
+    AddScreenWakeLockListener();
+  }
+
+  nsresult rv = nsBaseAppShell::Run();
+
+  if (XRE_IsParentProcess()) {
+    RemoveScreenWakeLockListener();
+  }
+  return rv;
+}
+
 void nsAppShell::ScheduleNativeEventCallback() {
   unsigned char buf[] = {NOTIFY_TOKEN};
   Unused << write(mPipeFDs[1], buf, 1);

widget/gtk/nsAppShell.h

@@ -15,16 +15,17 @@
 #endif
 #include <glib.h>
 #include "nsBaseAppShell.h"
-#include "nsCOMPtr.h"
 
 class nsAppShell : public nsBaseAppShell {
  public:
-  nsAppShell() : mTag(0) { mPipeFDs[0] = mPipeFDs[1] = 0; }
+  nsAppShell() = default;
 
   // nsBaseAppShell overrides:
   nsresult Init();
-  virtual void ScheduleNativeEventCallback() override;
+  NS_IMETHOD Run() override;
-  virtual bool ProcessNextNativeEvent(bool mayWait) override;
+
+  void ScheduleNativeEventCallback() override;
+  bool ProcessNextNativeEvent(bool mayWait) override;
 
 #ifdef MOZ_ENABLE_DBUS
   void StartDBusListening();
@@ -48,8 +49,8 @@ class nsAppShell : public nsBaseAppShell {
 
   static gboolean EventProcessorCallback(GIOChannel* source,
                                          GIOCondition condition, gpointer data);
-  int mPipeFDs[2];
+  int mPipeFDs[2] = {0, 0};
-  unsigned mTag;
+  unsigned mTag = 0;
 
 #ifdef MOZ_ENABLE_DBUS
   RefPtr<GDBusProxy> mLogin1Proxy;

widget/gtk/nsWidgetFactory.cpp

@@ -64,5 +64,4 @@ void nsWidgetGtk2ModuleDtor() {
   KeymapWrapper::Shutdown();
   nsGTKToolkit::Shutdown();
   nsAppShellShutdown();
-  WakeLockListener::Shutdown();
 }