API/JSAPIWrapperObject.mm

   1 /*
   2  * Copyright (C) 2013 Apple Inc. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
  14  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
  15  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  16  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
  17  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  18  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  19  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  20  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  21  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  22  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
  23  * THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #include "config.h"
  27 #include "JSAPIWrapperObject.h"
  28
  29 #include "DelayedReleaseScope.h"
  30 #include "JSCInlines.h"
  31 #include "JSCallbackObject.h"
  32 #include "JSVirtualMachineInternal.h"
  33 #include "Structure.h"
  34
  35 #if JSC_OBJC_API_ENABLED
  36
  37 class JSAPIWrapperObjectHandleOwner : public JSC::WeakHandleOwner {
  38 public:
  39     virtual void finalize(JSC::Handle<JSC::Unknown>, void*) override;
  40     virtual bool isReachableFromOpaqueRoots(JSC::Handle<JSC::Unknown>, void* context, JSC::SlotVisitor&) override;
  41 };
  42
  43 static JSAPIWrapperObjectHandleOwner* jsAPIWrapperObjectHandleOwner()
  44 {
  45     DEPRECATED_DEFINE_STATIC_LOCAL(JSAPIWrapperObjectHandleOwner, jsWrapperObjectHandleOwner, ());
  46     return &jsWrapperObjectHandleOwner;
  47 }
  48
  49 void JSAPIWrapperObjectHandleOwner::finalize(JSC::Handle<JSC::Unknown> handle, void*)
  50 {
  51     JSC::JSAPIWrapperObject* wrapperObject = JSC::jsCast<JSC::JSAPIWrapperObject*>(handle.get().asCell());
  52     if (!wrapperObject->wrappedObject())
  53         return;
  54
  55     JSC::Heap::heap(wrapperObject)->releaseSoon(adoptNS(static_cast<id>(wrapperObject->wrappedObject())));
  56     JSC::WeakSet::deallocate(JSC::WeakImpl::asWeakImpl(handle.slot()));
  57 }
  58
  59 bool JSAPIWrapperObjectHandleOwner::isReachableFromOpaqueRoots(JSC::Handle<JSC::Unknown> handle, void*, JSC::SlotVisitor& visitor)
  60 {
  61     JSC::JSAPIWrapperObject* wrapperObject = JSC::jsCast<JSC::JSAPIWrapperObject*>(handle.get().asCell());
  62     // We use the JSGlobalObject when processing weak handles to prevent the situation where using
  63     // the same Objective-C object in multiple global objects keeps all of the global objects alive.
  64     if (!wrapperObject->wrappedObject())
  65         return false;
  66     return JSC::Heap::isMarked(wrapperObject->structure()->globalObject()) && visitor.containsOpaqueRoot(wrapperObject->wrappedObject());
  67 }
  68
  69 namespace JSC {
  70
  71 template <> const ClassInfo JSCallbackObject<JSAPIWrapperObject>::s_info = { "JSAPIWrapperObject", &Base::s_info, 0, 0, CREATE_METHOD_TABLE(JSCallbackObject) };
  72
  73 template<> const bool JSCallbackObject<JSAPIWrapperObject>::needsDestruction = true;
  74
  75 template <>
  76 Structure* JSCallbackObject<JSAPIWrapperObject>::createStructure(VM& vm, JSGlobalObject* globalObject, JSValue proto)
  77 {
  78     return Structure::create(vm, globalObject, proto, TypeInfo(ObjectType, StructureFlags), &s_info);
  79 }
  80
  81 JSAPIWrapperObject::JSAPIWrapperObject(VM& vm, Structure* structure)
  82     : Base(vm, structure)
  83     , m_wrappedObject(0)
  84 {
  85 }
  86
  87 void JSAPIWrapperObject::finishCreation(VM& vm)
  88 {
  89     Base::finishCreation(vm);
  90     WeakSet::allocate(this, jsAPIWrapperObjectHandleOwner(), 0); // Balanced in JSAPIWrapperObjectHandleOwner::finalize.
  91 }
  92
  93 void JSAPIWrapperObject::setWrappedObject(void* wrappedObject)
  94 {
  95     ASSERT(!m_wrappedObject);
  96     m_wrappedObject = [static_cast<id>(wrappedObject) retain];
  97 }
  98
  99 void JSAPIWrapperObject::visitChildren(JSCell* cell, JSC::SlotVisitor& visitor)
 100 {
 101     JSAPIWrapperObject* thisObject = JSC::jsCast<JSAPIWrapperObject*>(cell);
 102     COMPILE_ASSERT(StructureFlags & OverridesVisitChildren, OverridesVisitChildrenWithoutSettingFlag);
 103     Base::visitChildren(cell, visitor);
 104
 105     if (thisObject->wrappedObject())
 106         scanExternalObjectGraph(cell->structure()->globalObject()->vm(), visitor, thisObject->wrappedObject());
 107 }
 108
 109 } // namespace JSC
 110
 111 #endif // JSC_OBJC_API_ENABLED