Bug 964462, simplify ipc offline resource refcounting, r=mayhemer

--HG--
extra : rebase_source : 362ce98a10c25f7e3263f23736a18d2bcfb16e75

dom/ipc/TabChild.cpp

@@ -2108,7 +2108,7 @@ bool
 TabChild::DeallocPOfflineCacheUpdateChild(POfflineCacheUpdateChild* actor)
 {
   OfflineCacheUpdateChild* offlineCacheUpdate = static_cast<OfflineCacheUpdateChild*>(actor);
-  delete offlineCacheUpdate;
+  NS_RELEASE(offlineCacheUpdate);
   return true;
 }
 

uriloader/prefetch/OfflineCacheUpdateChild.cpp

@@ -67,18 +67,7 @@ NS_INTERFACE_MAP_BEGIN(OfflineCacheUpdateChild)
 NS_INTERFACE_MAP_END
 
 NS_IMPL_ADDREF(OfflineCacheUpdateChild)
-NS_IMPL_RELEASE_WITH_DESTROY(OfflineCacheUpdateChild, RefcountHitZero())
-
-void
-OfflineCacheUpdateChild::RefcountHitZero()
-{
-    if (mIPCActivated) {
-        // ContentChild::DeallocPOfflineCacheUpdate will delete this
-        OfflineCacheUpdateChild::Send__delete__(this);
-    } else {
-        delete this;    // we never opened IPDL channel
-    }
-}
+NS_IMPL_RELEASE(OfflineCacheUpdateChild)
 
 //-----------------------------------------------------------------------------
 // OfflineCacheUpdateChild <public>
@@ -87,7 +76,6 @@ OfflineCacheUpdateChild::RefcountHitZero()
 OfflineCacheUpdateChild::OfflineCacheUpdateChild(nsIDOMWindow* aWindow)
     : mState(STATE_UNINITIALIZED)
     , mIsUpgrade(false)
-    , mIPCActivated(false)
     , mAppID(NECKO_NO_APP_ID)
     , mInBrowser(false)
     , mWindow(aWindow)
@@ -448,8 +436,8 @@ OfflineCacheUpdateChild::Schedule()
     child->SendPOfflineCacheUpdateConstructor(this, manifestURI, documentURI,
                                               stickDocument);
 
-    mIPCActivated = true;
-    this->AddRef();
+    // TabChild::DeallocPOfflineCacheUpdate will release this.
+    NS_ADDREF_THIS();
 
     return NS_OK;
 }
@@ -537,7 +525,8 @@ OfflineCacheUpdateChild::RecvFinish(const bool &succeeded,
 
     // This is by contract the last notification from the parent, release
     // us now. This is corresponding to AddRef in Schedule().
-    this->Release();
+    // TabChild::DeallocPOfflineCacheUpdate will call Release.
+    OfflineCacheUpdateChild::Send__delete__(this);
 
     return true;
 }

uriloader/prefetch/OfflineCacheUpdateChild.h

@@ -53,8 +53,6 @@ private:
     void GatherObservers(nsCOMArray<nsIOfflineCacheUpdateObserver> &aObservers);
     nsresult Finish();
 
-    void RefcountHitZero();
-
     enum {
         STATE_UNINITIALIZED,
         STATE_INITIALIZED,
@@ -66,7 +64,6 @@ private:
 
     bool mIsUpgrade;
     bool mSucceeded;
-    bool mIPCActivated;
 
     nsCString mUpdateDomain;
     nsCOMPtr<nsIURI> mManifestURI;

uriloader/prefetch/nsOfflineCacheUpdate.cpp

@@ -1157,7 +1157,6 @@ NS_IMPL_ISUPPORTS3(nsOfflineCacheUpdate,
 
 nsOfflineCacheUpdate::nsOfflineCacheUpdate()
     : mState(STATE_UNINITIALIZED)
-    , mOwner(nullptr)
     , mAddedItems(false)
     , mPartialUpdate(false)
     , mOnlyCheckUpdate(false)
@@ -1986,7 +1985,7 @@ void
 nsOfflineCacheUpdate::SetOwner(nsOfflineCacheUpdateOwner *aOwner)
 {
     NS_ASSERTION(!mOwner, "Tried to set cache update owner twice.");
-    mOwner = aOwner;
+    mOwner = aOwner->asWeakPtr();
 }
 
 bool
@@ -2107,7 +2106,9 @@ nsOfflineCacheUpdate::FinishNoNotify()
 
     if (mOwner) {
         rv = mOwner->UpdateFinished(this);
-        mOwner = nullptr;
+        // mozilla::WeakPtr is missing some key features, like setting it to
+        // null explicitly.
+        mOwner = mozilla::WeakPtr<nsOfflineCacheUpdateOwner>();
     }
 
     return rv;

uriloader/prefetch/nsOfflineCacheUpdate.h

@@ -31,6 +31,7 @@
 #include "nsWeakReference.h"
 #include "nsICryptoHash.h"
 #include "mozilla/Attributes.h"
+#include "mozilla/WeakPtr.h"
 #include "nsTHashtable.h"
 #include "nsHashKeys.h"
 
@@ -185,8 +186,10 @@ private:
 };
 
 class nsOfflineCacheUpdateOwner
+  : public mozilla::SupportsWeakPtr<nsOfflineCacheUpdateOwner>
 {
 public:
+    virtual ~nsOfflineCacheUpdateOwner() {}
     virtual nsresult UpdateFinished(nsOfflineCacheUpdate *aUpdate) = 0;
 };
 
@@ -261,7 +264,7 @@ private:
         STATE_FINISHED
     } mState;
 
-    nsOfflineCacheUpdateOwner *mOwner;
+    mozilla::WeakPtr<nsOfflineCacheUpdateOwner> mOwner;
 
     bool mAddedItems;
     bool mPartialUpdate;