1 files changed, 152 insertions, 0 deletions
diff --git a/xpcom/base/AppShutdown.h b/xpcom/base/AppShutdown.h
new file mode 100644
index 0000000000..6056338900
--- /dev/null
+++ b/xpcom/base/AppShutdown.h
@@ -0,0 +1,152 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef AppShutdown_h
+#define AppShutdown_h
+
+#include <type_traits>
+#include "nsCOMPtr.h"
+#include "nsISupports.h"
+#include "ShutdownPhase.h"
+
+namespace mozilla {
+
+enum class AppShutdownMode {
+  Normal,
+  Restart,
+};
+
+enum class AppShutdownReason {
+  // No reason.
+  Unknown,
+  // Normal application shutdown.
+  AppClose,
+  // The application wants to restart.
+  AppRestart,
+  // The OS is force closing us.
+  OSForceClose,
+  // The user is logging off from the OS session, the system may stay alive.
+  OSSessionEnd,
+  // The system is shutting down (and maybe restarting).
+  OSShutdown,
+  // We unexpectedly received MOZ_WM_APP_QUIT, see bug 1827807.
+  WinUnexpectedMozQuit,
+};
+
+class AppShutdown {
+ public:
+  static ShutdownPhase GetCurrentShutdownPhase();
+  static bool IsInOrBeyond(ShutdownPhase aPhase);
+
+  /**
+   * Returns the current exit code that the process will be terminated with.
+   */
+  static int GetExitCode();
+
+  /**
+   * Save environment variables that we might need if the app initiates a
+   * restart later in its lifecycle.
+   */
+  static void SaveEnvVarsForPotentialRestart();
+
+  /**
+   * Init the shutdown with the requested shutdown mode, exit code and optional
+   * a reason (if missing it will be derived from aMode).
+   */
+  static void Init(AppShutdownMode aMode, int aExitCode,
+                   AppShutdownReason aReason);
+
+  /**
+   * Confirm that we are in fact going to be shutting down.
+   */
+  static void OnShutdownConfirmed();
+
+  /**
+   * If we've attempted to initiate a restart, this call will set up the
+   * necessary environment variables and launch the new process.
+   */
+  static void MaybeDoRestart();
+
+  /**
+   * The _exit() call is not a safe way to terminate your own process on
+   * Windows, because _exit runs DLL detach callbacks which run static
+   * destructors for xul.dll.
+   *
+   * This method terminates the current process without those issues.
+   *
+   * Optionally a custom exit code can be supplied.
+   */
+  static void DoImmediateExit(int aExitCode = 0);
+
+  /**
+   * True if the application is currently attempting to shut down in order to
+   * restart.
+   */
+  static bool IsRestarting();
+
+  /**
+   * Wrapper for shutdown notifications that informs the terminator before
+   * we notify other observers. Calls MaybeFastShutdown.
+   */
+  static void AdvanceShutdownPhase(
+      ShutdownPhase aPhase, const char16_t* aNotificationData = nullptr,
+      const nsCOMPtr<nsISupports>& aNotificationSubject =
+          nsCOMPtr<nsISupports>(nullptr));
+
+  /**
+   * XXX: Before tackling bug 1697745 we need the
+   * possibility to advance the phase without notification
+   * in the content process.
+   */
+  static void AdvanceShutdownPhaseWithoutNotify(ShutdownPhase aPhase);
+
+  /**
+   * Map shutdown phase to observer key
+   */
+  static const char* GetObserverKey(ShutdownPhase aPhase);
+
+  /**
+   * Map shutdown phase to readable name
+   */
+  static const char* GetShutdownPhaseName(ShutdownPhase aPhase);
+
+  /**
+   * Map observer topic key to shutdown phase
+   */
+  static ShutdownPhase GetShutdownPhaseFromTopic(const char* aTopic);
+
+#ifdef DEBUG
+  /**
+   * Check, if we are allowed to send a shutdown notification.
+   * Shutdown specific topics are only allowed during calls to
+   * AdvanceShutdownPhase itself.
+   */
+  static bool IsNoOrLegalShutdownTopic(const char* aTopic);
+#endif
+
+ private:
+  /**
+   * Set the shutdown reason annotation.
+   */
+  static void AnnotateShutdownReason(AppShutdownReason aReason);
+
+  /**
+   * This will perform a fast shutdown via _exit(0) or similar if the user's
+   * prefs are configured to do so at this phase.
+   */
+  static void MaybeFastShutdown(ShutdownPhase aPhase);
+
+  /**
+   * Internal helper function, uses MaybeFastShutdown.
+   */
+  static void AdvanceShutdownPhaseInternal(
+      ShutdownPhase aPhase, bool doNotify, const char16_t* aNotificationData,
+      const nsCOMPtr<nsISupports>& aNotificationSubject);
+};
+
+}  // namespace mozilla
+
+#endif  // AppShutdown_h