Bug 1492629 - de-COM mozJSComponentLoader. r=mccr8

Differential Revision: https://phabricator.services.mozilla.com/D18388

--HG--
extra : moz-landing-system : lando

js/xpconnect/loader/mozJSComponentLoader.cpp

@@ -30,7 +30,6 @@
 #include "mozJSComponentLoader.h"
 #include "mozJSLoaderUtils.h"
 #include "nsIXPConnect.h"
-#include "nsIObserverService.h"
 #include "nsIScriptSecurityManager.h"
 #include "nsIFileURL.h"
 #include "nsIJARURI.h"
@@ -66,9 +65,6 @@ using namespace mozilla::loader;
 using namespace xpc;
 using namespace JS;
 
-static const char kObserverServiceContractID[] =
-    "@mozilla.org/observer-service;1";
-
 #define JS_CACHE_PREFIX(aType) "jsloader/" aType
 
 /**
@@ -297,7 +293,7 @@ static nsresult ReportOnCallerUTF8(JSCLContextHelper& helper,
 mozJSComponentLoader::~mozJSComponentLoader() {
   if (mInitialized) {
     NS_ERROR(
-        "'xpcom-shutdown-loaders' was not fired before cleaning up "
+        "UnloadModules() was not explicitly called before cleaning up "
         "mozJSComponentLoader");
     UnloadModules();
   }
@@ -307,8 +303,6 @@ mozJSComponentLoader::~mozJSComponentLoader() {
 
 StaticRefPtr<mozJSComponentLoader> mozJSComponentLoader::sSelf;
 
-NS_IMPL_ISUPPORTS(mozJSComponentLoader, nsIObserver)
-
 nsresult mozJSComponentLoader::ReallyInit() {
   MOZ_ASSERT(!mInitialized);
 
@@ -323,14 +317,6 @@ nsresult mozJSComponentLoader::ReallyInit() {
     mShareLoaderGlobal = Preferences::GetBool("jsloader.shareGlobal");
   }
 
-  nsresult rv;
-  nsCOMPtr<nsIObserverService> obsSvc =
-      do_GetService(kObserverServiceContractID, &rv);
-  NS_ENSURE_SUCCESS(rv, rv);
-
-  rv = obsSvc->AddObserver(this, "xpcom-shutdown-loaders", false);
-  NS_ENSURE_SUCCESS(rv, rv);
-
   mInitialized = true;
 
   return NS_OK;
@@ -538,6 +524,12 @@ void mozJSComponentLoader::InitStatics() {
   sSelf = new mozJSComponentLoader();
 }
 
+void mozJSComponentLoader::Unload() {
+  if (sSelf) {
+    sSelf->UnloadModules();
+  }
+}
+
 void mozJSComponentLoader::Shutdown() {
   MOZ_ASSERT(sSelf);
   sSelf = nullptr;
@@ -1406,18 +1398,6 @@ nsresult mozJSComponentLoader::Unload(const nsACString& aLocation) {
   return NS_OK;
 }
 
-NS_IMETHODIMP
-mozJSComponentLoader::Observe(nsISupports* subject, const char* topic,
-                              const char16_t* data) {
-  if (!strcmp(topic, "xpcom-shutdown-loaders")) {
-    UnloadModules();
-  } else {
-    NS_ERROR("Unexpected observer topic.");
-  }
-
-  return NS_OK;
-}
-
 size_t mozJSComponentLoader::ModuleEntry::SizeOfIncludingThis(
     MallocSizeOf aMallocSizeOf) const {
   size_t n = aMallocSizeOf(this);

js/xpconnect/loader/mozJSComponentLoader.h

@@ -14,7 +14,6 @@
 #include "mozilla/StaticPtr.h"
 #include "nsAutoPtr.h"
 #include "nsISupports.h"
-#include "nsIObserver.h"
 #include "nsIURI.h"
 #include "nsClassHashtable.h"
 #include "nsDataHashtable.h"
@@ -34,12 +33,9 @@ class ScriptPreloader;
 #  define STARTUP_RECORDER_ENABLED
 #endif
 
-class mozJSComponentLoader final : public nsIObserver {
+class mozJSComponentLoader final {
  public:
-  NS_DECL_ISUPPORTS
-  NS_DECL_NSIOBSERVER
-
-  mozJSComponentLoader();
+  NS_INLINE_DECL_REFCOUNTING(mozJSComponentLoader);
 
   void GetLoadedModules(nsTArray<nsCString>& aLoadedModules);
   void GetLoadedComponents(nsTArray<nsCString>& aLoadedComponents);
@@ -53,6 +49,7 @@ class mozJSComponentLoader final : public nsIObserver {
   void FindTargetObject(JSContext* aCx, JS::MutableHandleObject aTargetObject);
 
   static void InitStatics();
+  static void Unload();
   static void Shutdown();
 
   static mozJSComponentLoader* Get() {
@@ -84,7 +81,8 @@ class mozJSComponentLoader final : public nsIObserver {
   nsresult AnnotateCrashReport();
 
  protected:
-  virtual ~mozJSComponentLoader();
+  mozJSComponentLoader();
+  ~mozJSComponentLoader();
 
   friend class XPCJSRuntime;
 

xpcom/build/XPCOMInit.cpp

@@ -14,6 +14,7 @@
 #include "mozilla/SharedThreadPool.h"
 #include "mozilla/VideoDecoderManagerChild.h"
 #include "mozilla/XPCOM.h"
+#include "mozJSComponentLoader.h"
 #include "nsXULAppAPI.h"
 
 #ifndef ANDROID
@@ -591,7 +592,6 @@ nsresult ShutdownXPCOM(nsIServiceManager* aServMgr) {
   }
 
   nsresult rv;
-  nsCOMPtr<nsISimpleEnumerator> moduleLoaders;
 
   // Notify observers of xpcom shutting down
   {
@@ -662,13 +662,8 @@ nsresult ShutdownXPCOM(nsIServiceManager* aServMgr) {
     // xpcshell tests replacing the service) modules being unloaded.
     mozilla::InitLateWriteChecks();
 
-    // We save the "xpcom-shutdown-loaders" observers to notify after
-    // the observerservice is gone.
     if (observerService) {
       mozilla::KillClearOnShutdown(ShutdownPhase::ShutdownLoaders);
-      observerService->EnumerateObservers(NS_XPCOM_SHUTDOWN_LOADERS_OBSERVER_ID,
-                                          getter_AddRefs(moduleLoaders));
-
       observerService->Shutdown();
     }
   }
@@ -698,28 +693,11 @@ nsresult ShutdownXPCOM(nsIServiceManager* aServMgr) {
   free(gGREBinPath);
   gGREBinPath = nullptr;
 
-  if (moduleLoaders) {
-    bool more;
-    nsCOMPtr<nsISupports> el;
-    while (NS_SUCCEEDED(moduleLoaders->HasMoreElements(&more)) && more) {
-      moduleLoaders->GetNext(getter_AddRefs(el));
-
-      // Don't worry about weak-reference observers here: there is
-      // no reason for weak-ref observers to register for
-      // xpcom-shutdown-loaders
-
-      // FIXME: This can cause harmless writes from sqlite committing
-      // log files. We have to ignore them before we can move
-      // the mozilla::PoisonWrite call before this point. See bug
-      // 834945 for the details.
-      nsCOMPtr<nsIObserver> obs(do_QueryInterface(el));
-      if (obs) {
-        obs->Observe(nullptr, NS_XPCOM_SHUTDOWN_LOADERS_OBSERVER_ID, nullptr);
-      }
-    }
-
-    moduleLoaders = nullptr;
-  }
+  // FIXME: This can cause harmless writes from sqlite committing
+  // log files. We have to ignore them before we can move
+  // the mozilla::PoisonWrite call before this point. See bug
+  // 834945 for the details.
+  mozJSComponentLoader::Unload();
 
   // Clear the profiler's JS context before cycle collection. The profiler will
   // notify the JS engine that it can let go of any data it's holding on to for

xpcom/build/moz.build

@@ -100,6 +100,7 @@ LOCAL_INCLUDES += [
     '../threads',
     '/chrome',
     '/docshell/base',
+    '/js/xpconnect/loader',
 ]
 
 if CONFIG['MOZ_VPX']:

xpcom/build/nsXPCOMPrivate.h

@@ -16,12 +16,6 @@
  */
 #define NS_XPCOM_SHUTDOWN_THREADS_OBSERVER_ID "xpcom-shutdown-threads"
 
-/**
- * During this shutdown notification all module loaders must unload XPCOM
- * modules.
- */
-#define NS_XPCOM_SHUTDOWN_LOADERS_OBSERVER_ID "xpcom-shutdown-loaders"
-
 // PUBLIC
 namespace mozilla {