Temporary fix for bug 92859. Components can now be registered with the generic module macros to have class info, but not be instantiable via the component manager. Currently, the class object of such components are created eagerly at module initialization time. A future fix might create them lazily. r/sr=jband, jst

xpcom/components/nsGenericFactory.cpp

@@ -55,7 +55,11 @@ NS_IMPL_THREADSAFE_ISUPPORTS3(nsGenericFactory,
 NS_IMETHODIMP nsGenericFactory::CreateInstance(nsISupports *aOuter,
                                                REFNSIID aIID, void **aResult)
 {
-    return mInfo->mConstructor(aOuter, aIID, aResult);
+    if (mInfo->mConstructor) {
+        return mInfo->mConstructor(aOuter, aIID, aResult);
+    }
+
+    return NS_ERROR_FACTORY_NOT_REGISTERED;
 }
 
 NS_IMETHODIMP nsGenericFactory::LockFactory(PRBool aLock)
@@ -210,6 +214,23 @@ nsGenericModule::Initialize()
     if (mInitialized) {
         return NS_OK;
     }
+
+    // Eagerly populate factory/class object hash for entries
+    // without constructors. If we didn't, the class object would
+    // never get created.
+    nsModuleComponentInfo* desc = mComponents;
+    for (PRUint32 i = 0; i < mComponentCount; i++) {
+        if (!desc->mConstructor) {
+            nsCOMPtr<nsIGenericFactory> fact;
+            nsresult rv = NS_NewGenericFactory(getter_AddRefs(fact), desc);
+            if (NS_FAILED(rv)) return rv;
+            
+            nsIDKey key(desc->mCID);
+            (void)mFactories.Put(&key, fact);
+        }
+        desc++;
+    }
+
     mInitialized = PR_TRUE;
     return NS_OK;
 }
@@ -292,16 +313,20 @@ nsGenericModule::RegisterSelf(nsIComponentManager *aCompMgr,
 
     nsModuleComponentInfo* cp = mComponents;
     for (PRUint32 i = 0; i < mComponentCount; i++) {
-        rv = aCompMgr->RegisterComponentWithType(cp->mCID, cp->mDescription,
-                                                 cp->mContractID, aPath,
-                                                 registryLocation, PR_TRUE,
-                                                 PR_TRUE, componentType);
-        if (NS_FAILED(rv)) {
+        // Register the component only if it has a constructor
+        if (cp->mConstructor) {
+            rv = aCompMgr->RegisterComponentWithType(cp->mCID, 
+                                                     cp->mDescription,
+                                                     cp->mContractID, aPath,
+                                                     registryLocation, PR_TRUE,
+                                                     PR_TRUE, componentType);
+            if (NS_FAILED(rv)) {
 #ifdef DEBUG
-            printf("nsGenericModule %s: unable to register %s component => %x\n",
-                   mModuleName?mModuleName:"(null)", cp->mDescription?cp->mDescription:"(null)", rv);
+                printf("nsGenericModule %s: unable to register %s component => %x\n",
+                       mModuleName?mModuleName:"(null)", cp->mDescription?cp->mDescription:"(null)", rv);
 #endif
-            break;
+                break;
+            }
         }
         // Call the registration hook of the component, if any
         if (cp->mRegisterSelfProc)

xpcom/glue/nsGenericFactory.cpp

@@ -55,7 +55,11 @@ NS_IMPL_THREADSAFE_ISUPPORTS3(nsGenericFactory,
 NS_IMETHODIMP nsGenericFactory::CreateInstance(nsISupports *aOuter,
                                                REFNSIID aIID, void **aResult)
 {
-    return mInfo->mConstructor(aOuter, aIID, aResult);
+    if (mInfo->mConstructor) {
+        return mInfo->mConstructor(aOuter, aIID, aResult);
+    }
+
+    return NS_ERROR_FACTORY_NOT_REGISTERED;
 }
 
 NS_IMETHODIMP nsGenericFactory::LockFactory(PRBool aLock)
@@ -210,6 +214,23 @@ nsGenericModule::Initialize()
     if (mInitialized) {
         return NS_OK;
     }
+
+    // Eagerly populate factory/class object hash for entries
+    // without constructors. If we didn't, the class object would
+    // never get created.
+    nsModuleComponentInfo* desc = mComponents;
+    for (PRUint32 i = 0; i < mComponentCount; i++) {
+        if (!desc->mConstructor) {
+            nsCOMPtr<nsIGenericFactory> fact;
+            nsresult rv = NS_NewGenericFactory(getter_AddRefs(fact), desc);
+            if (NS_FAILED(rv)) return rv;
+            
+            nsIDKey key(desc->mCID);
+            (void)mFactories.Put(&key, fact);
+        }
+        desc++;
+    }
+
     mInitialized = PR_TRUE;
     return NS_OK;
 }
@@ -292,16 +313,20 @@ nsGenericModule::RegisterSelf(nsIComponentManager *aCompMgr,
 
     nsModuleComponentInfo* cp = mComponents;
     for (PRUint32 i = 0; i < mComponentCount; i++) {
-        rv = aCompMgr->RegisterComponentWithType(cp->mCID, cp->mDescription,
-                                                 cp->mContractID, aPath,
-                                                 registryLocation, PR_TRUE,
-                                                 PR_TRUE, componentType);
-        if (NS_FAILED(rv)) {
+        // Register the component only if it has a constructor
+        if (cp->mConstructor) {
+            rv = aCompMgr->RegisterComponentWithType(cp->mCID, 
+                                                     cp->mDescription,
+                                                     cp->mContractID, aPath,
+                                                     registryLocation, PR_TRUE,
+                                                     PR_TRUE, componentType);
+            if (NS_FAILED(rv)) {
 #ifdef DEBUG
-            printf("nsGenericModule %s: unable to register %s component => %x\n",
-                   mModuleName?mModuleName:"(null)", cp->mDescription?cp->mDescription:"(null)", rv);
+                printf("nsGenericModule %s: unable to register %s component => %x\n",
+                       mModuleName?mModuleName:"(null)", cp->mDescription?cp->mDescription:"(null)", rv);
 #endif
-            break;
+                break;
+            }
         }
         // Call the registration hook of the component, if any
         if (cp->mRegisterSelfProc)