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 <JavaScriptCore/JSObjectRef.h>
  30
  31 #include "Weak.h"
  32 #include "Protect.h"
  33 #include <wtf/HashMap.h>
  34 #include <wtf/text/WTFString.h>
  35
  36 struct StaticValueEntry {
  37     WTF_MAKE_FAST_ALLOCATED;
  38 public:
  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 {
  50     WTF_MAKE_FAST_ALLOCATED;
  51 public:
  52     StaticFunctionEntry(JSObjectCallAsFunctionCallback _callAsFunction, JSPropertyAttributes _attributes)
  53         : callAsFunction(_callAsFunction), attributes(_attributes)
  54     {
  55     }
  56
  57     JSObjectCallAsFunctionCallback callAsFunction;
  58     JSPropertyAttributes attributes;
  59 };
  60
  61 typedef HashMap<RefPtr<StringImpl>, OwnPtr<StaticValueEntry> > OpaqueJSClassStaticValuesTable;
  62 typedef HashMap<RefPtr<StringImpl>, OwnPtr<StaticFunctionEntry> > OpaqueJSClassStaticFunctionsTable;
  63
  64 struct OpaqueJSClass;
  65
  66 // An OpaqueJSClass (JSClass) is created without a context, so it can be used with any context, even across context groups.
  67 // This structure holds data members that vary across context groups.
  68 struct OpaqueJSClassContextData {
  69     WTF_MAKE_NONCOPYABLE(OpaqueJSClassContextData); WTF_MAKE_FAST_ALLOCATED;
  70 public:
  71     OpaqueJSClassContextData(JSC::VM&, OpaqueJSClass*);
  72
  73     // It is necessary to keep OpaqueJSClass alive because of the following rare scenario:
  74     // 1. A class is created and used, so its context data is stored in VM hash map.
  75     // 2. The class is released, and when all JS objects that use it are collected, OpaqueJSClass
  76     // is deleted (that's the part prevented by this RefPtr).
  77     // 3. Another class is created at the same address.
  78     // 4. When it is used, the old context data is found in VM and used.
  79     RefPtr<OpaqueJSClass> m_class;
  80
  81     OwnPtr<OpaqueJSClassStaticValuesTable> staticValues;
  82     OwnPtr<OpaqueJSClassStaticFunctionsTable> staticFunctions;
  83     JSC::Weak<JSC::JSObject> cachedPrototype;
  84 };
  85
  86 struct OpaqueJSClass : public ThreadSafeRefCounted<OpaqueJSClass> {
  87     static PassRefPtr<OpaqueJSClass> create(const JSClassDefinition*);
  88     static PassRefPtr<OpaqueJSClass> createNoAutomaticPrototype(const JSClassDefinition*);
  89     JS_EXPORT_PRIVATE ~OpaqueJSClass();
  90
  91     String className();
  92     OpaqueJSClassStaticValuesTable* staticValues(JSC::ExecState*);
  93     OpaqueJSClassStaticFunctionsTable* staticFunctions(JSC::ExecState*);
  94     JSC::JSObject* prototype(JSC::ExecState*);
  95
  96     OpaqueJSClass* parentClass;
  97     OpaqueJSClass* prototypeClass;
  98
  99     JSObjectInitializeCallback initialize;
 100     JSObjectFinalizeCallback finalize;
 101     JSObjectHasPropertyCallback hasProperty;
 102     JSObjectGetPropertyCallback getProperty;
 103     JSObjectSetPropertyCallback setProperty;
 104     JSObjectDeletePropertyCallback deleteProperty;
 105     JSObjectGetPropertyNamesCallback getPropertyNames;
 106     JSObjectCallAsFunctionCallback callAsFunction;
 107     JSObjectCallAsConstructorCallback callAsConstructor;
 108     JSObjectHasInstanceCallback hasInstance;
 109     JSObjectConvertToTypeCallback convertToType;
 110
 111 private:
 112     friend struct OpaqueJSClassContextData;
 113
 114     OpaqueJSClass();
 115     OpaqueJSClass(const OpaqueJSClass&);
 116     OpaqueJSClass(const JSClassDefinition*, OpaqueJSClass* protoClass);
 117
 118     OpaqueJSClassContextData& contextData(JSC::ExecState*);
 119
 120     // Strings in these data members should not be put into any IdentifierTable.
 121     String m_className;
 122     OwnPtr<OpaqueJSClassStaticValuesTable> m_staticValues;
 123     OwnPtr<OpaqueJSClassStaticFunctionsTable> m_staticFunctions;
 124 };
 125
 126 #endif // JSClassRef_h