Bug 906503 - Remove nsIExceptionProvider; r=bholley

It is replaced by a direct special case in the caller.

dom/base/moz.build

@@ -22,6 +22,7 @@ EXPORTS += [
     'nsDOMCID.h',
     'nsDOMClassInfoClasses.h',
     'nsDOMClassInfoID.h',
+    'nsDOMException.h',
     'nsDOMJSUtils.h',
     'nsDOMNavigationTiming.h',
     'nsDOMString.h',

dom/base/nsDOMScriptObjectFactory.cpp

@@ -33,8 +33,6 @@
 
 using mozilla::dom::GetNameSpaceManager;
 
-nsIExceptionProvider* gExceptionProvider = nullptr;
-
 nsDOMScriptObjectFactory::nsDOMScriptObjectFactory()
 {
   nsCOMPtr<nsIObserverService> observerService =
@@ -43,20 +41,6 @@ nsDOMScriptObjectFactory::nsDOMScriptObjectFactory()
     observerService->AddObserver(this, NS_XPCOM_SHUTDOWN_OBSERVER_ID, false);
   }
 
-  nsCOMPtr<nsIExceptionProvider> provider = new nsDOMExceptionProvider();
-  nsCOMPtr<nsIExceptionService> xs =
-    do_GetService(NS_EXCEPTIONSERVICE_CONTRACTID);
-
-  if (xs) {
-    xs->RegisterExceptionProvider(provider, NS_ERROR_MODULE_DOM);
-    xs->RegisterExceptionProvider(provider, NS_ERROR_MODULE_SVG);
-    xs->RegisterExceptionProvider(provider, NS_ERROR_MODULE_DOM_XPATH);
-    xs->RegisterExceptionProvider(provider, NS_ERROR_MODULE_DOM_INDEXEDDB);
-    xs->RegisterExceptionProvider(provider, NS_ERROR_MODULE_DOM_FILEHANDLE);
-  }
-
-  NS_ASSERTION(!gExceptionProvider, "Registered twice?!");
-  provider.swap(gExceptionProvider);
 }
 
 NS_INTERFACE_MAP_BEGIN(nsDOMScriptObjectFactory)
@@ -121,26 +105,6 @@ nsDOMScriptObjectFactory::Observe(nsISupports *aSubject,
 
     nsGlobalWindow::ShutDown();
     nsDOMClassInfo::ShutDown();
-
-    if (gExceptionProvider) {
-      nsCOMPtr<nsIExceptionService> xs =
-        do_GetService(NS_EXCEPTIONSERVICE_CONTRACTID);
-
-      if (xs) {
-        xs->UnregisterExceptionProvider(gExceptionProvider,
-                                        NS_ERROR_MODULE_DOM);
-        xs->UnregisterExceptionProvider(gExceptionProvider,
-                                        NS_ERROR_MODULE_SVG);
-        xs->UnregisterExceptionProvider(gExceptionProvider,
-                                        NS_ERROR_MODULE_DOM_XPATH);
-        xs->UnregisterExceptionProvider(gExceptionProvider,
-                                        NS_ERROR_MODULE_DOM_INDEXEDDB);
-        xs->UnregisterExceptionProvider(gExceptionProvider,
-                                        NS_ERROR_MODULE_DOM_FILEHANDLE);
-      }
-
-      NS_RELEASE(gExceptionProvider);
-    }
   }
 
   return NS_OK;
@@ -166,31 +130,3 @@ nsDOMScriptObjectFactory::RegisterDOMClassInfo(const char *aName,
                                              aHasClassInterface,
                                              aConstructorCID);
 }
-
-NS_IMPL_ISUPPORTS1(nsDOMExceptionProvider, nsIExceptionProvider)
-
-NS_IMETHODIMP
-nsDOMExceptionProvider::GetException(nsresult result,
-                                     nsIException *aDefaultException,
-                                     nsIException **_retval)
-{
-  if (!NS_IsMainThread()) {
-    return NS_ERROR_NOT_IMPLEMENTED;
-  }
-
-  switch (NS_ERROR_GET_MODULE(result))
-  {
-    case NS_ERROR_MODULE_DOM:
-    case NS_ERROR_MODULE_SVG:
-    case NS_ERROR_MODULE_DOM_XPATH:
-    case NS_ERROR_MODULE_DOM_FILE:
-    case NS_ERROR_MODULE_DOM_INDEXEDDB:
-    case NS_ERROR_MODULE_DOM_FILEHANDLE:
-      return NS_NewDOMException(result, aDefaultException, _retval);
-    default:
-      NS_WARNING("Trying to create an exception for the wrong error module.");
-      return NS_ERROR_FAILURE;
-  }
-  NS_NOTREACHED("Not reached");
-  return NS_ERROR_UNEXPECTED;
-}

dom/base/nsDOMScriptObjectFactory.h

@@ -20,7 +20,6 @@
 
 #include "nsIDOMScriptObjectFactory.h"
 #include "nsIObserver.h"
-#include "nsIExceptionService.h"
 #include "mozilla/Attributes.h"
 
 class nsDOMScriptObjectFactory MOZ_FINAL : public nsIDOMScriptObjectFactory,
@@ -47,9 +46,3 @@ public:
                                   const nsCID *aConstructorCID) MOZ_OVERRIDE;
 };
 
-class nsDOMExceptionProvider MOZ_FINAL : public nsIExceptionProvider
-{
-public:
-  NS_DECL_THREADSAFE_ISUPPORTS
-  NS_DECL_NSIEXCEPTIONPROVIDER
-};

dom/base/nsJSEnvironment.cpp

@@ -2853,10 +2853,10 @@ nsJSContext::EnsureStatics()
   obs->AddObserver(observer, "memory-pressure", false);
   obs->AddObserver(observer, "quit-application", false);
 
-  // We need to explicitly get the nsIDOMScriptObjectFactory service in order
-  // to force its constructor to run, which registers various exceptions
-  // providers and other things. It would be nice to make this more explicit
-  // and less side-effect-y.
+  // Bug 907848 - We need to explicitly get the nsIDOMScriptObjectFactory
+  // service in order to force its constructor to run, which registers a
+  // shutdown observer. It would be nice to make this more explicit and less
+  // side-effect-y.
   nsCOMPtr<nsIDOMScriptObjectFactory> factory = do_GetService(kDOMScriptObjectFactoryCID);
   if (!factory) {
     MOZ_CRASH();

xpcom/base/nsExceptionService.cpp

@@ -3,16 +3,18 @@
  * 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/. */
 
+#include "nsExceptionService.h"
+
 #include "mozilla/Attributes.h"
 #include "mozilla/DebugOnly.h"
-
-#include "nsISupports.h"
-#include "nsExceptionService.h"
-#include "nsIServiceManager.h"
+#include "mozilla/Services.h"
 #include "nsCOMPtr.h"
+#include "nsDOMException.h"
+#include "nsIServiceManager.h"
+#include "nsISupports.h"
+#include "nsThreadUtils.h"
 #include "pratom.h"
 #include "prthread.h"
-#include "mozilla/Services.h"
 
 using namespace mozilla;
 
@@ -21,24 +23,6 @@ static const unsigned BAD_TLS_INDEX = (unsigned) -1;
 #define CHECK_SERVICE_USE_OK() if (!sLock) return NS_ERROR_NOT_INITIALIZED
 #define CHECK_MANAGER_USE_OK() if (!mService || !nsExceptionService::sLock) return NS_ERROR_NOT_INITIALIZED
 
-// A key for our registered module providers hashtable
-class nsProviderKey : public nsHashKey {
-protected:
-  uint32_t mKey;
-public:
-  nsProviderKey(uint32_t key) : mKey(key) {}
-  uint32_t HashCode(void) const {
-    return mKey;
-  }
-  bool Equals(const nsHashKey *aKey) const {
-    return mKey == ((const nsProviderKey *) aKey)->mKey;
-  }
-  nsHashKey *Clone() const {
-    return new nsProviderKey(mKey);
-  }
-  uint32_t GetValue() { return mKey; }
-};
-
 /** Exception Manager definition **/
 class nsExceptionManager MOZ_FINAL : public nsIExceptionManager
 {
@@ -129,7 +113,6 @@ NS_IMPL_ISUPPORTS3(nsExceptionService,
                    nsIObserver)
 
 nsExceptionService::nsExceptionService()
-  : mProviders(4, true) /* small, thread-safe hashtable */
 {
 #ifdef DEBUG
   if (PR_ATOMIC_INCREMENT(&totalInstances)!=1) {
@@ -174,7 +157,6 @@ void nsExceptionService::ThreadDestruct( void *data )
 
 void nsExceptionService::Shutdown()
 {
-  mProviders.Reset();
   if (sLock) {
     DropAllThreads();
     delete sLock;
@@ -230,30 +212,6 @@ NS_IMETHODIMP nsExceptionService::GetCurrentExceptionManager(nsIExceptionManager
     return NS_OK;
 }
 
-/* void registerErrorProvider (in nsIExceptionProvider provider, in uint32_t moduleCode); */
-NS_IMETHODIMP nsExceptionService::RegisterExceptionProvider(nsIExceptionProvider *provider, uint32_t errorModule)
-{
-    CHECK_SERVICE_USE_OK();
-
-    nsProviderKey key(errorModule);
-    if (mProviders.Put(&key, provider)) {
-        NS_WARNING("Registration of exception provider overwrote another provider with the same module code!");
-    }
-    return NS_OK;
-}
-
-/* void unregisterErrorProvider (in nsIExceptionProvider provider, in uint32_t errorModule); */
-NS_IMETHODIMP nsExceptionService::UnregisterExceptionProvider(nsIExceptionProvider *provider, uint32_t errorModule)
-{
-    CHECK_SERVICE_USE_OK();
-    nsProviderKey key(errorModule);
-    if (!mProviders.Remove(&key)) {
-        NS_WARNING("Attempt to unregister an unregistered exception provider!");
-        return NS_ERROR_UNEXPECTED;
-    }
-    return NS_OK;
-}
-
 // nsIObserver
 NS_IMETHODIMP nsExceptionService::Observe(nsISupports *aSubject, const char *aTopic, const PRUnichar *someData)
 {
@@ -275,18 +233,26 @@ nsExceptionService::DoGetExceptionFromProvider(nsresult errCode,
             return NS_OK;
         NS_RELEASE(*_exc);
     }
-    nsProviderKey key(NS_ERROR_GET_MODULE(errCode));
-    nsCOMPtr<nsIExceptionProvider> provider =
-        dont_AddRef((nsIExceptionProvider *)mProviders.Get(&key));
 
-    // No provider so we'll return the default exception
-    if (!provider) {
-        *_exc = defaultException;
-        NS_IF_ADDREF(*_exc);
-        return NS_OK;
+    switch (NS_ERROR_GET_MODULE(errCode)) {
+    case NS_ERROR_MODULE_DOM:
+    case NS_ERROR_MODULE_SVG:
+    case NS_ERROR_MODULE_DOM_XPATH:
+    case NS_ERROR_MODULE_DOM_INDEXEDDB:
+    case NS_ERROR_MODULE_DOM_FILEHANDLE:
+        if (NS_IsMainThread()) {
+            return NS_NewDOMException(errCode, defaultException, _exc);
+        }
+        break;
+
+    default:
+        break;
     }
 
-    return provider->GetException(errCode, defaultException, _exc);
+    // No provider so we'll return the default exception
+    *_exc = defaultException;
+    NS_IF_ADDREF(*_exc);
+    return NS_OK;
 }
 
 // thread management

xpcom/base/nsExceptionService.h

@@ -43,10 +43,7 @@ public:
   static void DropAllThreads();
   static nsExceptionManager *firstThread;
 
-  nsSupportsHashtable mProviders;
-
-  /* single lock protects both providers hashtable
-     and thread list */
+  /* Protects the thread list. */
   static mozilla::Mutex* sLock;
 
   static unsigned tlsIndex;

xpcom/base/nsIExceptionService.idl

@@ -6,16 +6,6 @@
 #include "nsISupports.idl"
 #include "nsIException.idl"
 
-// An exception provider.  These can turn special nsresult codes
-// into nsIExceptions
-
-[scriptable, uuid(0577744c-c1d2-47f2-8bcc-ce7a9e5a88fc)]
-interface nsIExceptionProvider : nsISupports
-{
-    /** Gets an nsIException or returns NULL if not possible. **/
-    nsIException getException(in nsresult result, in nsIException defaultException);
-};
-
 // A ScriptErrorManager for a single thread.  These objects
 // are _not_ thread-safe.  Use the ScriptErrorService
 // to get a script error manager for your current thread.
@@ -36,22 +26,11 @@ interface nsIExceptionManager : nsISupports
 
 // The Exception Service.  Allows you to get an set exceptions in a thread
 // safe manner, or to get an ExceptionManager for your specific thread.
-[scriptable, uuid(35A88F54-F267-4414-92A7-191F6454AB52)]
+[scriptable, uuid(8f9ccabb-a68b-43e3-b570-dd8c3179d2fb)]
 interface nsIExceptionService : nsIExceptionManager
 {
     /** Obtains an exception manager for the current thread. */
     readonly attribute nsIExceptionManager currentExceptionManager;
-
-    /** Installs an "exception provider" which is capable of
-        translating an nsresult into an exception.  This enables
-        error providers to return simple nsresults and only provide
-        rich errors when specifically requested. It also has the
-        advantage of allowing code like the DOM to handle all errors
-        in a single function rather than at each XPCOM entry point.
-        NOTE: This interface must be thread-safe - it will be called
-        on whatever thread needs the error translation performed.*/
-    void registerExceptionProvider( in nsIExceptionProvider provider, in uint32_t moduleCode );
-    void unregisterExceptionProvider( in nsIExceptionProvider provider, in uint32_t moduleCode );
 };