Bug 234858: Make do_GetWeakReference typesafe.

r=dbaron sr=bryner

extensions/pref/system-pref/src/gconf/nsSystemPrefService.cpp

@@ -411,7 +411,8 @@ NS_IMETHODIMP nsSystemPrefService::AddObserver(const char *aDomain, nsIObserver
             nsMemory::Free(pCallbackData);
             return NS_ERROR_INVALID_ARG;
         }
-        observerRef = do_GetWeakReference(weakRefFactory);
+        nsCOMPtr<nsIWeakReference> tmp = do_GetWeakReference(weakRefFactory);
+        observerRef = tmp;
     } else {
         observerRef = aObserver;
     }
@@ -460,8 +461,11 @@ NS_IMETHODIMP nsSystemPrefService::RemoveObserver(const char *aDomain, nsIObserv
             if (pCallbackData->bIsWeakRef) {
                 nsCOMPtr<nsISupportsWeakReference> weakRefFactory =
                     do_QueryInterface(aObserver);
-                if (weakRefFactory)
-                    observerRef = do_GetWeakReference(aObserver);
+                if (weakRefFactory) {
+                    nsCOMPtr<nsIWeakReference> tmp =
+                        do_GetWeakReference(aObserver);
+                    observerRef = tmp;
+                }
             }
             if (!observerRef)
                 observerRef = aObserver;

modules/libpref/src/nsPrefBranch.cpp

@@ -635,7 +635,8 @@ NS_IMETHODIMP nsPrefBranch::AddObserver(const char *aDomain, nsIObserver *aObser
       nsMemory::Free(pCallback);
       return NS_ERROR_INVALID_ARG;
     }
-    observerRef = do_GetWeakReference(weakRefFactory);
+    nsCOMPtr<nsIWeakReference> tmp = do_GetWeakReference(weakRefFactory);
+    observerRef = tmp;
   } else {
     observerRef = aObserver;
   }
@@ -677,8 +678,10 @@ NS_IMETHODIMP nsPrefBranch::RemoveObserver(const char *aDomain, nsIObserver *aOb
      nsCOMPtr<nsISupports> observerRef;
      if (pCallback->bIsWeakRef) {
        nsCOMPtr<nsISupportsWeakReference> weakRefFactory = do_QueryInterface(aObserver);
-       if (weakRefFactory)
-         observerRef = do_GetWeakReference(aObserver);
+       if (weakRefFactory) {
+         nsCOMPtr<nsIWeakReference> tmp = do_GetWeakReference(aObserver);
+         observerRef = tmp;
+       }
      }
      if (!observerRef)
        observerRef = aObserver;

xpcom/glue/nsIWeakReferenceUtils.h

@@ -89,23 +89,12 @@ do_QueryReferent( nsIWeakReference* aRawPtr, nsresult* error = 0 )
   }
 
 
-
-class NS_COM_GLUE nsGetWeakReference : public nsCOMPtr_helper
-  {
-    public:
-      nsGetWeakReference( nsISupports* aRawPtr, nsresult* error )
-          : mRawPtr(aRawPtr),
-            mErrorPtr(error)
-        {
-          // nothing else to do here
-        }
-
-      virtual nsresult NS_FASTCALL operator()( const nsIID&, void** ) const;
-
-    private:
-      nsISupports*  mRawPtr;
-      nsresult*     mErrorPtr;
-  };
+  /**
+   * Deprecated, use |do_GetWeakReference| instead.
+   */
+extern NS_COM_GLUE
+nsIWeakReference*
+NS_GetWeakReference( nsISupports* , nsresult* aResult=0 );
 
   /**
    * |do_GetWeakReference| is a convenience function that bundles up all the work needed
@@ -115,10 +104,10 @@ class NS_COM_GLUE nsGetWeakReference : public nsCOMPtr_helper
    * |nsWeakPtr myWeakPtr = do_GetWeakReference(aPtr);|.
    */
 inline
-const nsGetWeakReference
+already_AddRefed<nsIWeakReference>
 do_GetWeakReference( nsISupports* aRawPtr, nsresult* error = 0 )
   {
-    return nsGetWeakReference(aRawPtr, error);
+    return NS_GetWeakReference(aRawPtr, error);
   }
 
 inline
@@ -150,13 +139,4 @@ do_GetWeakReference( already_AddRefed<T>&, nsresult* )
     //  someone else is an automatic leak.  See <http://bugzilla.mozilla.org/show_bug.cgi?id=8221>.
   }
 
-
-
-  /**
-   * Deprecated, use |do_GetWeakReference| instead.
-   */
-extern NS_COM_GLUE
-nsIWeakReference*
-NS_GetWeakReference( nsISupports* , nsresult* aResult=0 );
-
 #endif

xpcom/glue/nsWeakReference.cpp

@@ -60,40 +60,29 @@ nsQueryReferent::operator()( const nsIID& aIID, void** answer ) const
     return status;
   }
 
-nsresult
-nsGetWeakReference::operator()( const nsIID&, void** aResult ) const
+NS_COM_GLUE nsIWeakReference*  // or else |already_AddRefed<nsIWeakReference>|
+NS_GetWeakReference( nsISupports* aInstancePtr, nsresult* aErrorPtr )
   {
     nsresult status;
-    // nsIWeakReference** result = &NS_STATIC_CAST(nsIWeakReference*, *aResult);
-    *aResult = 0;
 
-    if ( mRawPtr )
+    nsIWeakReference* result = nsnull;
+
+    if ( aInstancePtr )
       {
-        nsCOMPtr<nsISupportsWeakReference> factoryPtr = do_QueryInterface(mRawPtr, &status);
+        nsCOMPtr<nsISupportsWeakReference> factoryPtr = do_QueryInterface(aInstancePtr, &status);
         NS_ASSERTION(factoryPtr, "Oops!  You're asking for a weak reference to an object that doesn't support that.");
         if ( factoryPtr )
           {
-            nsIWeakReference* temp;
-            status = factoryPtr->GetWeakReference(&temp);
-            *aResult = temp;
+            status = factoryPtr->GetWeakReference(&result);
           }
         // else, |status| has already been set by |do_QueryInterface|
       }
     else
       status = NS_ERROR_NULL_POINTER;
 
-    if ( mErrorPtr )
-      *mErrorPtr = status;
-    return status;
-  }
-
-
-NS_COM_GLUE nsIWeakReference*  // or else |already_AddRefed<nsIWeakReference>|
-NS_GetWeakReference( nsISupports* aInstancePtr, nsresult* aErrorPtr )
-  {
-    void* result = 0;
-    nsGetWeakReference(aInstancePtr, aErrorPtr)(NS_GET_IID(nsIWeakReference), &result);
-    return NS_STATIC_CAST(nsIWeakReference*, result);
+    if ( aErrorPtr )
+      *aErrorPtr = status;
+    return result;
   }
 
 NS_COM_GLUE nsresult
@@ -118,49 +107,7 @@ nsSupportsWeakReference::GetWeakReference( nsIWeakReference** aInstancePtr )
     return status;
   }
 
-NS_IMETHODIMP_(nsrefcnt)
-nsWeakReference::AddRef()
-  {
-    return ++mRefCount;
-  }
-
-NS_IMETHODIMP_(nsrefcnt)
-nsWeakReference::Release()
-  {
-    nsrefcnt temp = --mRefCount;
-    if ( !mRefCount )
-      delete this;
-    return temp;
-  }
-
-NS_IMETHODIMP
-nsWeakReference::QueryInterface( const nsIID& aIID, void** aInstancePtr )
-  {
-    NS_ASSERTION(aInstancePtr, "QueryInterface requires a non-NULL destination!");
-
-    if ( !aInstancePtr )
-      return NS_ERROR_NULL_POINTER;
-
-    nsISupports* foundInterface;
-    if ( aIID.Equals(NS_GET_IID(nsIWeakReference)) )
-      foundInterface = NS_STATIC_CAST(nsIWeakReference*, this);
-    else if ( aIID.Equals(NS_GET_IID(nsISupports)) )
-      foundInterface = NS_STATIC_CAST(nsISupports*, this);
-    else
-      foundInterface = 0;
-
-    nsresult status;
-    if ( !foundInterface )
-      status = NS_NOINTERFACE;
-    else
-      {
-        NS_ADDREF(foundInterface);
-        status = NS_OK;
-      }
-
-    *aInstancePtr = foundInterface;
-    return status;
-  }
+NS_IMPL_ISUPPORTS1(nsWeakReference, nsIWeakReference)
 
 NS_IMETHODIMP
 nsWeakReference::QueryReferent( const nsIID& aIID, void** aInstancePtr )

xpcom/glue/nsWeakReference.h

@@ -89,9 +89,7 @@ class NS_COM_GLUE nsWeakReference : public nsIWeakReference
   {
     public:
     // nsISupports...
-      NS_IMETHOD_(nsrefcnt) AddRef();
-      NS_IMETHOD_(nsrefcnt) Release();
-      NS_IMETHOD QueryInterface( const nsIID&, void** );
+      NS_DECL_ISUPPORTS
 
     // nsIWeakReference...
       NS_DECL_NSIWEAKREFERENCE
@@ -100,8 +98,7 @@ class NS_COM_GLUE nsWeakReference : public nsIWeakReference
       friend class nsSupportsWeakReference;
 
       nsWeakReference( nsSupportsWeakReference* referent )
-          : mRefCount(0),
-            mReferent(referent)
+          : mReferent(referent)
           // ...I can only be constructed by an |nsSupportsWeakReference|
         {
           // nothing else to do here
@@ -121,7 +118,6 @@ class NS_COM_GLUE nsWeakReference : public nsIWeakReference
           mReferent = 0;
         }
 
-      nsrefcnt                  mRefCount;
       nsSupportsWeakReference*  mReferent;
   };