michael@0: /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #ifndef mozilla_JSEventHandler_h_
michael@0: #define mozilla_JSEventHandler_h_
michael@0: 
michael@0: #include "mozilla/Attributes.h"
michael@0: #include "mozilla/MemoryReporting.h"
michael@0: #include "mozilla/dom/EventHandlerBinding.h"
michael@0: #include "nsCOMPtr.h"
michael@0: #include "nsCycleCollectionParticipant.h"
michael@0: #include "nsIAtom.h"
michael@0: #include "nsIDOMKeyEvent.h"
michael@0: #include "nsIDOMEventListener.h"
michael@0: #include "nsIScriptContext.h"
michael@0: 
michael@0: namespace mozilla {
michael@0: 
michael@0: class TypedEventHandler
michael@0: {
michael@0: public:
michael@0:   enum HandlerType
michael@0:   {
michael@0:     eUnset = 0,
michael@0:     eNormal = 0x1,
michael@0:     eOnError = 0x2,
michael@0:     eOnBeforeUnload = 0x3,
michael@0:     eTypeBits = 0x3
michael@0:   };
michael@0: 
michael@0:   TypedEventHandler()
michael@0:     : mBits(0)
michael@0:   {
michael@0:   }
michael@0: 
michael@0:   TypedEventHandler(dom::EventHandlerNonNull* aHandler)
michael@0:   {
michael@0:     Assign(aHandler, eNormal);
michael@0:   }
michael@0: 
michael@0:   TypedEventHandler(dom::OnErrorEventHandlerNonNull* aHandler)
michael@0:   {
michael@0:     Assign(aHandler, eOnError);
michael@0:   }
michael@0: 
michael@0:   TypedEventHandler(dom::OnBeforeUnloadEventHandlerNonNull* aHandler)
michael@0:   {
michael@0:     Assign(aHandler, eOnBeforeUnload);
michael@0:   }
michael@0: 
michael@0:   TypedEventHandler(const TypedEventHandler& aOther)
michael@0:   {
michael@0:     if (aOther.HasEventHandler()) {
michael@0:       // Have to make sure we take our own ref
michael@0:       Assign(aOther.Ptr(), aOther.Type());
michael@0:     } else {
michael@0:       mBits = 0;
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   ~TypedEventHandler()
michael@0:   {
michael@0:     ReleaseHandler();
michael@0:   }
michael@0: 
michael@0:   HandlerType Type() const
michael@0:   {
michael@0:     return HandlerType(mBits & eTypeBits);
michael@0:   }
michael@0: 
michael@0:   bool HasEventHandler() const
michael@0:   {
michael@0:     return !!Ptr();
michael@0:   }
michael@0: 
michael@0:   void SetHandler(const TypedEventHandler& aHandler)
michael@0:   {
michael@0:     if (aHandler.HasEventHandler()) {
michael@0:       ReleaseHandler();
michael@0:       Assign(aHandler.Ptr(), aHandler.Type());
michael@0:     } else {
michael@0:       ForgetHandler();
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   dom::EventHandlerNonNull* NormalEventHandler() const
michael@0:   {
michael@0:     MOZ_ASSERT(Type() == eNormal && Ptr());
michael@0:     return reinterpret_cast<dom::EventHandlerNonNull*>(Ptr());
michael@0:   }
michael@0: 
michael@0:   void SetHandler(dom::EventHandlerNonNull* aHandler)
michael@0:   {
michael@0:     ReleaseHandler();
michael@0:     Assign(aHandler, eNormal);
michael@0:   }
michael@0: 
michael@0:   dom::OnBeforeUnloadEventHandlerNonNull* OnBeforeUnloadEventHandler() const
michael@0:   {
michael@0:     MOZ_ASSERT(Type() == eOnBeforeUnload);
michael@0:     return reinterpret_cast<dom::OnBeforeUnloadEventHandlerNonNull*>(Ptr());
michael@0:   }
michael@0: 
michael@0:   void SetHandler(dom::OnBeforeUnloadEventHandlerNonNull* aHandler)
michael@0:   {
michael@0:     ReleaseHandler();
michael@0:     Assign(aHandler, eOnBeforeUnload);
michael@0:   }
michael@0: 
michael@0:   dom::OnErrorEventHandlerNonNull* OnErrorEventHandler() const
michael@0:   {
michael@0:     MOZ_ASSERT(Type() == eOnError);
michael@0:     return reinterpret_cast<dom::OnErrorEventHandlerNonNull*>(Ptr());
michael@0:   }
michael@0: 
michael@0:   void SetHandler(dom::OnErrorEventHandlerNonNull* aHandler)
michael@0:   {
michael@0:     ReleaseHandler();
michael@0:     Assign(aHandler, eOnError);
michael@0:   }
michael@0: 
michael@0:   dom::CallbackFunction* Ptr() const
michael@0:   {
michael@0:     // Have to cast eTypeBits so we don't have to worry about
michael@0:     // promotion issues after the bitflip.
michael@0:     return reinterpret_cast<dom::CallbackFunction*>(mBits &
michael@0:                                                       ~uintptr_t(eTypeBits));
michael@0:   }
michael@0: 
michael@0:   void ForgetHandler()
michael@0:   {
michael@0:     ReleaseHandler();
michael@0:     mBits = 0;
michael@0:   }
michael@0: 
michael@0:   bool operator==(const TypedEventHandler& aOther) const
michael@0:   {
michael@0:     return
michael@0:       Ptr() && aOther.Ptr() &&
michael@0:       Ptr()->CallbackPreserveColor() == aOther.Ptr()->CallbackPreserveColor();
michael@0:   }
michael@0: 
michael@0: private:
michael@0:   void operator=(const TypedEventHandler&) MOZ_DELETE;
michael@0: 
michael@0:   void ReleaseHandler()
michael@0:   {
michael@0:     nsISupports* ptr = Ptr();
michael@0:     NS_IF_RELEASE(ptr);
michael@0:   }
michael@0: 
michael@0:   void Assign(nsISupports* aHandler, HandlerType aType)
michael@0:   {
michael@0:     MOZ_ASSERT(aHandler, "Must have handler");
michael@0:     NS_ADDREF(aHandler);
michael@0:     mBits = uintptr_t(aHandler) | uintptr_t(aType);
michael@0:   }
michael@0: 
michael@0:   uintptr_t mBits;
michael@0: };
michael@0: 
michael@0: /**
michael@0:  * Implemented by script event listeners. Used to retrieve the script object
michael@0:  * corresponding to the event target and the handler itself.
michael@0:  *
michael@0:  * Note, mTarget is a raw pointer and the owner of the JSEventHandler object
michael@0:  * is expected to call Disconnect()!
michael@0:  */
michael@0: 
michael@0: #define NS_JSEVENTHANDLER_IID \
michael@0: { 0x4f486881, 0x1956, 0x4079, \
michael@0:   { 0x8c, 0xa0, 0xf3, 0xbd, 0x60, 0x5c, 0xc2, 0x79 } }
michael@0: 
michael@0: class JSEventHandler : public nsIDOMEventListener
michael@0: {
michael@0: public:
michael@0:   NS_DECLARE_STATIC_IID_ACCESSOR(NS_JSEVENTHANDLER_IID)
michael@0: 
michael@0:   JSEventHandler(nsISupports* aTarget, nsIAtom* aType,
michael@0:                  const TypedEventHandler& aTypedHandler);
michael@0: 
michael@0:   virtual ~JSEventHandler();
michael@0: 
michael@0:   NS_DECL_CYCLE_COLLECTING_ISUPPORTS
michael@0: 
michael@0:   // nsIDOMEventListener interface
michael@0:   NS_DECL_NSIDOMEVENTLISTENER
michael@0: 
michael@0:   nsISupports* GetEventTarget() const
michael@0:   {
michael@0:     return mTarget;
michael@0:   }
michael@0: 
michael@0:   void Disconnect()
michael@0:   {
michael@0:     mTarget = nullptr;
michael@0:   }
michael@0: 
michael@0:   const TypedEventHandler& GetTypedEventHandler() const
michael@0:   {
michael@0:     return mTypedHandler;
michael@0:   }
michael@0: 
michael@0:   void ForgetHandler()
michael@0:   {
michael@0:     mTypedHandler.ForgetHandler();
michael@0:   }
michael@0: 
michael@0:   nsIAtom* EventName() const
michael@0:   {
michael@0:     return mEventName;
michael@0:   }
michael@0: 
michael@0:   // Set a handler for this event listener.  The handler must already
michael@0:   // be bound to the right target.
michael@0:   void SetHandler(const TypedEventHandler& aTypedHandler)
michael@0:   {
michael@0:     mTypedHandler.SetHandler(aTypedHandler);
michael@0:   }
michael@0:   void SetHandler(dom::EventHandlerNonNull* aHandler)
michael@0:   {
michael@0:     mTypedHandler.SetHandler(aHandler);
michael@0:   }
michael@0:   void SetHandler(dom::OnBeforeUnloadEventHandlerNonNull* aHandler)
michael@0:   {
michael@0:     mTypedHandler.SetHandler(aHandler);
michael@0:   }
michael@0:   void SetHandler(dom::OnErrorEventHandlerNonNull* aHandler)
michael@0:   {
michael@0:     mTypedHandler.SetHandler(aHandler);
michael@0:   }
michael@0: 
michael@0:   size_t SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const
michael@0:   {
michael@0:     return 0;
michael@0: 
michael@0:     // Measurement of the following members may be added later if DMD finds it
michael@0:     // is worthwhile:
michael@0:     // - mTarget
michael@0:     //
michael@0:     // The following members are not measured:
michael@0:     // - mTypedHandler: may be shared with others
michael@0:     // - mEventName: shared with others
michael@0:   }
michael@0: 
michael@0:   size_t SizeOfIncludingThis(MallocSizeOf aMallocSizeOf)
michael@0:   {
michael@0:     return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf);
michael@0:   }
michael@0: 
michael@0:   NS_DECL_CYCLE_COLLECTION_SKIPPABLE_CLASS(JSEventHandler)
michael@0: 
michael@0:   bool IsBlackForCC();
michael@0: 
michael@0: protected:
michael@0:   nsISupports* mTarget;
michael@0:   nsCOMPtr<nsIAtom> mEventName;
michael@0:   TypedEventHandler mTypedHandler;
michael@0: };
michael@0: 
michael@0: NS_DEFINE_STATIC_IID_ACCESSOR(JSEventHandler, NS_JSEVENTHANDLER_IID)
michael@0: 
michael@0: } // namespace mozilla
michael@0: 
michael@0: /**
michael@0:  * Factory function.  aHandler must already be bound to aTarget.
michael@0:  * aContext is allowed to be null if aHandler is already set up.
michael@0:  */
michael@0: nsresult NS_NewJSEventHandler(nsISupports* aTarget,
michael@0:                               nsIAtom* aType,
michael@0:                               const mozilla::TypedEventHandler& aTypedHandler,
michael@0:                               mozilla::JSEventHandler** aReturn);
michael@0: 
michael@0: #endif // mozilla_JSEventHandler_h_
michael@0: