1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/dom/events/JSEventHandler.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,277 @@
1.4 +/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.7 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +
1.9 +#ifndef mozilla_JSEventHandler_h_
1.10 +#define mozilla_JSEventHandler_h_
1.11 +
1.12 +#include "mozilla/Attributes.h"
1.13 +#include "mozilla/MemoryReporting.h"
1.14 +#include "mozilla/dom/EventHandlerBinding.h"
1.15 +#include "nsCOMPtr.h"
1.16 +#include "nsCycleCollectionParticipant.h"
1.17 +#include "nsIAtom.h"
1.18 +#include "nsIDOMKeyEvent.h"
1.19 +#include "nsIDOMEventListener.h"
1.20 +#include "nsIScriptContext.h"
1.21 +
1.22 +namespace mozilla {
1.23 +
1.24 +class TypedEventHandler
1.25 +{
1.26 +public:
1.27 + enum HandlerType
1.28 + {
1.29 + eUnset = 0,
1.30 + eNormal = 0x1,
1.31 + eOnError = 0x2,
1.32 + eOnBeforeUnload = 0x3,
1.33 + eTypeBits = 0x3
1.34 + };
1.35 +
1.36 + TypedEventHandler()
1.37 + : mBits(0)
1.38 + {
1.39 + }
1.40 +
1.41 + TypedEventHandler(dom::EventHandlerNonNull* aHandler)
1.42 + {
1.43 + Assign(aHandler, eNormal);
1.44 + }
1.45 +
1.46 + TypedEventHandler(dom::OnErrorEventHandlerNonNull* aHandler)
1.47 + {
1.48 + Assign(aHandler, eOnError);
1.49 + }
1.50 +
1.51 + TypedEventHandler(dom::OnBeforeUnloadEventHandlerNonNull* aHandler)
1.52 + {
1.53 + Assign(aHandler, eOnBeforeUnload);
1.54 + }
1.55 +
1.56 + TypedEventHandler(const TypedEventHandler& aOther)
1.57 + {
1.58 + if (aOther.HasEventHandler()) {
1.59 + // Have to make sure we take our own ref
1.60 + Assign(aOther.Ptr(), aOther.Type());
1.61 + } else {
1.62 + mBits = 0;
1.63 + }
1.64 + }
1.65 +
1.66 + ~TypedEventHandler()
1.67 + {
1.68 + ReleaseHandler();
1.69 + }
1.70 +
1.71 + HandlerType Type() const
1.72 + {
1.73 + return HandlerType(mBits & eTypeBits);
1.74 + }
1.75 +
1.76 + bool HasEventHandler() const
1.77 + {
1.78 + return !!Ptr();
1.79 + }
1.80 +
1.81 + void SetHandler(const TypedEventHandler& aHandler)
1.82 + {
1.83 + if (aHandler.HasEventHandler()) {
1.84 + ReleaseHandler();
1.85 + Assign(aHandler.Ptr(), aHandler.Type());
1.86 + } else {
1.87 + ForgetHandler();
1.88 + }
1.89 + }
1.90 +
1.91 + dom::EventHandlerNonNull* NormalEventHandler() const
1.92 + {
1.93 + MOZ_ASSERT(Type() == eNormal && Ptr());
1.94 + return reinterpret_cast<dom::EventHandlerNonNull*>(Ptr());
1.95 + }
1.96 +
1.97 + void SetHandler(dom::EventHandlerNonNull* aHandler)
1.98 + {
1.99 + ReleaseHandler();
1.100 + Assign(aHandler, eNormal);
1.101 + }
1.102 +
1.103 + dom::OnBeforeUnloadEventHandlerNonNull* OnBeforeUnloadEventHandler() const
1.104 + {
1.105 + MOZ_ASSERT(Type() == eOnBeforeUnload);
1.106 + return reinterpret_cast<dom::OnBeforeUnloadEventHandlerNonNull*>(Ptr());
1.107 + }
1.108 +
1.109 + void SetHandler(dom::OnBeforeUnloadEventHandlerNonNull* aHandler)
1.110 + {
1.111 + ReleaseHandler();
1.112 + Assign(aHandler, eOnBeforeUnload);
1.113 + }
1.114 +
1.115 + dom::OnErrorEventHandlerNonNull* OnErrorEventHandler() const
1.116 + {
1.117 + MOZ_ASSERT(Type() == eOnError);
1.118 + return reinterpret_cast<dom::OnErrorEventHandlerNonNull*>(Ptr());
1.119 + }
1.120 +
1.121 + void SetHandler(dom::OnErrorEventHandlerNonNull* aHandler)
1.122 + {
1.123 + ReleaseHandler();
1.124 + Assign(aHandler, eOnError);
1.125 + }
1.126 +
1.127 + dom::CallbackFunction* Ptr() const
1.128 + {
1.129 + // Have to cast eTypeBits so we don't have to worry about
1.130 + // promotion issues after the bitflip.
1.131 + return reinterpret_cast<dom::CallbackFunction*>(mBits &
1.132 + ~uintptr_t(eTypeBits));
1.133 + }
1.134 +
1.135 + void ForgetHandler()
1.136 + {
1.137 + ReleaseHandler();
1.138 + mBits = 0;
1.139 + }
1.140 +
1.141 + bool operator==(const TypedEventHandler& aOther) const
1.142 + {
1.143 + return
1.144 + Ptr() && aOther.Ptr() &&
1.145 + Ptr()->CallbackPreserveColor() == aOther.Ptr()->CallbackPreserveColor();
1.146 + }
1.147 +
1.148 +private:
1.149 + void operator=(const TypedEventHandler&) MOZ_DELETE;
1.150 +
1.151 + void ReleaseHandler()
1.152 + {
1.153 + nsISupports* ptr = Ptr();
1.154 + NS_IF_RELEASE(ptr);
1.155 + }
1.156 +
1.157 + void Assign(nsISupports* aHandler, HandlerType aType)
1.158 + {
1.159 + MOZ_ASSERT(aHandler, "Must have handler");
1.160 + NS_ADDREF(aHandler);
1.161 + mBits = uintptr_t(aHandler) | uintptr_t(aType);
1.162 + }
1.163 +
1.164 + uintptr_t mBits;
1.165 +};
1.166 +
1.167 +/**
1.168 + * Implemented by script event listeners. Used to retrieve the script object
1.169 + * corresponding to the event target and the handler itself.
1.170 + *
1.171 + * Note, mTarget is a raw pointer and the owner of the JSEventHandler object
1.172 + * is expected to call Disconnect()!
1.173 + */
1.174 +
1.175 +#define NS_JSEVENTHANDLER_IID \
1.176 +{ 0x4f486881, 0x1956, 0x4079, \
1.177 + { 0x8c, 0xa0, 0xf3, 0xbd, 0x60, 0x5c, 0xc2, 0x79 } }
1.178 +
1.179 +class JSEventHandler : public nsIDOMEventListener
1.180 +{
1.181 +public:
1.182 + NS_DECLARE_STATIC_IID_ACCESSOR(NS_JSEVENTHANDLER_IID)
1.183 +
1.184 + JSEventHandler(nsISupports* aTarget, nsIAtom* aType,
1.185 + const TypedEventHandler& aTypedHandler);
1.186 +
1.187 + virtual ~JSEventHandler();
1.188 +
1.189 + NS_DECL_CYCLE_COLLECTING_ISUPPORTS
1.190 +
1.191 + // nsIDOMEventListener interface
1.192 + NS_DECL_NSIDOMEVENTLISTENER
1.193 +
1.194 + nsISupports* GetEventTarget() const
1.195 + {
1.196 + return mTarget;
1.197 + }
1.198 +
1.199 + void Disconnect()
1.200 + {
1.201 + mTarget = nullptr;
1.202 + }
1.203 +
1.204 + const TypedEventHandler& GetTypedEventHandler() const
1.205 + {
1.206 + return mTypedHandler;
1.207 + }
1.208 +
1.209 + void ForgetHandler()
1.210 + {
1.211 + mTypedHandler.ForgetHandler();
1.212 + }
1.213 +
1.214 + nsIAtom* EventName() const
1.215 + {
1.216 + return mEventName;
1.217 + }
1.218 +
1.219 + // Set a handler for this event listener. The handler must already
1.220 + // be bound to the right target.
1.221 + void SetHandler(const TypedEventHandler& aTypedHandler)
1.222 + {
1.223 + mTypedHandler.SetHandler(aTypedHandler);
1.224 + }
1.225 + void SetHandler(dom::EventHandlerNonNull* aHandler)
1.226 + {
1.227 + mTypedHandler.SetHandler(aHandler);
1.228 + }
1.229 + void SetHandler(dom::OnBeforeUnloadEventHandlerNonNull* aHandler)
1.230 + {
1.231 + mTypedHandler.SetHandler(aHandler);
1.232 + }
1.233 + void SetHandler(dom::OnErrorEventHandlerNonNull* aHandler)
1.234 + {
1.235 + mTypedHandler.SetHandler(aHandler);
1.236 + }
1.237 +
1.238 + size_t SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const
1.239 + {
1.240 + return 0;
1.241 +
1.242 + // Measurement of the following members may be added later if DMD finds it
1.243 + // is worthwhile:
1.244 + // - mTarget
1.245 + //
1.246 + // The following members are not measured:
1.247 + // - mTypedHandler: may be shared with others
1.248 + // - mEventName: shared with others
1.249 + }
1.250 +
1.251 + size_t SizeOfIncludingThis(MallocSizeOf aMallocSizeOf)
1.252 + {
1.253 + return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf);
1.254 + }
1.255 +
1.256 + NS_DECL_CYCLE_COLLECTION_SKIPPABLE_CLASS(JSEventHandler)
1.257 +
1.258 + bool IsBlackForCC();
1.259 +
1.260 +protected:
1.261 + nsISupports* mTarget;
1.262 + nsCOMPtr<nsIAtom> mEventName;
1.263 + TypedEventHandler mTypedHandler;
1.264 +};
1.265 +
1.266 +NS_DEFINE_STATIC_IID_ACCESSOR(JSEventHandler, NS_JSEVENTHANDLER_IID)
1.267 +
1.268 +} // namespace mozilla
1.269 +
1.270 +/**
1.271 + * Factory function. aHandler must already be bound to aTarget.
1.272 + * aContext is allowed to be null if aHandler is already set up.
1.273 + */
1.274 +nsresult NS_NewJSEventHandler(nsISupports* aTarget,
1.275 + nsIAtom* aType,
1.276 + const mozilla::TypedEventHandler& aTypedHandler,
1.277 + mozilla::JSEventHandler** aReturn);
1.278 +
1.279 +#endif // mozilla_JSEventHandler_h_
1.280 +
