API/JSClassRef.h

   1 /*
   2  * Copyright (C) 2006 Apple Computer, 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 COMPUTER, INC. ``AS IS'' AND ANY
  14  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  16  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
  17  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  18  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  19  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  20  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  21  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  23  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #ifndef JSClassRef_h
  27 #define JSClassRef_h
  28
  29 #include "JSObjectRef.h"
  30
  31 #include <runtime/JSObject.h>
  32 #include <runtime/Protect.h>
  33 #include <runtime/UString.h>
  34 #include <runtime/WeakGCPtr.h>
  35 #include <wtf/HashMap.h>
  36 #include <wtf/RefCounted.h>
  37
  38 struct StaticValueEntry : FastAllocBase {
  39     StaticValueEntry(JSObjectGetPropertyCallback _getProperty, JSObjectSetPropertyCallback _setProperty, JSPropertyAttributes _attributes)
  40         : getProperty(_getProperty), setProperty(_setProperty), attributes(_attributes)
  41     {
  42     }
  43
  44     JSObjectGetPropertyCallback getProperty;
  45     JSObjectSetPropertyCallback setProperty;
  46     JSPropertyAttributes attributes;
  47 };
  48
  49 struct StaticFunctionEntry : FastAllocBase {
  50     StaticFunctionEntry(JSObjectCallAsFunctionCallback _callAsFunction, JSPropertyAttributes _attributes)
  51         : callAsFunction(_callAsFunction), attributes(_attributes)
  52     {
  53     }
  54
  55     JSObjectCallAsFunctionCallback callAsFunction;
  56     JSPropertyAttributes attributes;
  57 };
  58
  59 typedef HashMap<RefPtr<JSC::UString::Rep>, StaticValueEntry*> OpaqueJSClassStaticValuesTable;
  60 typedef HashMap<RefPtr<JSC::UString::Rep>, StaticFunctionEntry*> OpaqueJSClassStaticFunctionsTable;
  61
  62 struct OpaqueJSClass;
  63
  64 // An OpaqueJSClass (JSClass) is created without a context, so it can be used with any context, even across context groups.
  65 // This structure holds data members that vary across context groups.
  66 struct OpaqueJSClassContextData : Noncopyable {
  67     OpaqueJSClassContextData(OpaqueJSClass*);
  68     ~OpaqueJSClassContextData();
  69
  70     // It is necessary to keep OpaqueJSClass alive because of the following rare scenario:
  71     // 1. A class is created and used, so its context data is stored in JSGlobalData hash map.
  72     // 2. The class is released, and when all JS objects that use it are collected, OpaqueJSClass
  73     // is deleted (that's the part prevented by this RefPtr).
  74     // 3. Another class is created at the same address.
  75     // 4. When it is used, the old context data is found in JSGlobalData and used.
  76     RefPtr<OpaqueJSClass> m_class;
  77
  78     OpaqueJSClassStaticValuesTable* staticValues;
  79     OpaqueJSClassStaticFunctionsTable* staticFunctions;
  80     JSC::WeakGCPtr<JSC::JSObject> cachedPrototype;
  81 };
  82
  83 struct OpaqueJSClass : public ThreadSafeShared<OpaqueJSClass> {
  84     static PassRefPtr<OpaqueJSClass> create(const JSClassDefinition*);
  85     static PassRefPtr<OpaqueJSClass> createNoAutomaticPrototype(const JSClassDefinition*);
  86     ~OpaqueJSClass();
  87
  88     JSC::UString className();
  89     OpaqueJSClassStaticValuesTable* staticValues(JSC::ExecState*);
  90     OpaqueJSClassStaticFunctionsTable* staticFunctions(JSC::ExecState*);
  91     JSC::JSObject* prototype(JSC::ExecState*);
  92
  93     OpaqueJSClass* parentClass;
  94     OpaqueJSClass* prototypeClass;
  95
  96     JSObjectInitializeCallback initialize;
  97     JSObjectFinalizeCallback finalize;
  98     JSObjectHasPropertyCallback hasProperty;
  99     JSObjectGetPropertyCallback getProperty;
 100     JSObjectSetPropertyCallback setProperty;
 101     JSObjectDeletePropertyCallback deleteProperty;
 102     JSObjectGetPropertyNamesCallback getPropertyNames;
 103     JSObjectCallAsFunctionCallback callAsFunction;
 104     JSObjectCallAsConstructorCallback callAsConstructor;
 105     JSObjectHasInstanceCallback hasInstance;
 106     JSObjectConvertToTypeCallback convertToType;
 107
 108 private:
 109     friend struct OpaqueJSClassContextData;
 110
 111     OpaqueJSClass();
 112     OpaqueJSClass(const OpaqueJSClass&);
 113     OpaqueJSClass(const JSClassDefinition*, OpaqueJSClass* protoClass);
 114
 115     OpaqueJSClassContextData& contextData(JSC::ExecState*);
 116
 117     // UStrings in these data members should not be put into any IdentifierTable.
 118     JSC::UString m_className;
 119     OpaqueJSClassStaticValuesTable* m_staticValues;
 120     OpaqueJSClassStaticFunctionsTable* m_staticFunctions;
 121 };
 122
 123 #endif // JSClassRef_h