API/JSClassRef.cpp

   1 /*
   2  * Copyright (C) 2006, 2007 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 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 #include "config.h"
  27 #include "JSClassRef.h"
  28
  29 #include "APICast.h"
  30 #include "Identifier.h"
  31 #include "InitializeThreading.h"
  32 #include "JSCallbackObject.h"
  33 #include "JSGlobalObject.h"
  34 #include "JSObjectRef.h"
  35 #include "ObjectPrototype.h"
  36 #include "Operations.h"
  37 #include <wtf/text/StringHash.h>
  38 #include <wtf/unicode/UTF8.h>
  39
  40 using namespace std;
  41 using namespace JSC;
  42 using namespace WTF::Unicode;
  43
  44 const JSClassDefinition kJSClassDefinitionEmpty = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
  45
  46 OpaqueJSClass::OpaqueJSClass(const JSClassDefinition* definition, OpaqueJSClass* protoClass)
  47     : parentClass(definition->parentClass)
  48     , prototypeClass(0)
  49     , initialize(definition->initialize)
  50     , finalize(definition->finalize)
  51     , hasProperty(definition->hasProperty)
  52     , getProperty(definition->getProperty)
  53     , setProperty(definition->setProperty)
  54     , deleteProperty(definition->deleteProperty)
  55     , getPropertyNames(definition->getPropertyNames)
  56     , callAsFunction(definition->callAsFunction)
  57     , callAsConstructor(definition->callAsConstructor)
  58     , hasInstance(definition->hasInstance)
  59     , convertToType(definition->convertToType)
  60     , m_className(String::fromUTF8(definition->className))
  61 {
  62     initializeThreading();
  63
  64     if (const JSStaticValue* staticValue = definition->staticValues) {
  65         m_staticValues = adoptPtr(new OpaqueJSClassStaticValuesTable);
  66         while (staticValue->name) {
  67             String valueName = String::fromUTF8(staticValue->name);
  68             if (!valueName.isNull())
  69                 m_staticValues->set(valueName.impl(), adoptPtr(new StaticValueEntry(staticValue->getProperty, staticValue->setProperty, staticValue->attributes)));
  70             ++staticValue;
  71         }
  72     }
  73
  74     if (const JSStaticFunction* staticFunction = definition->staticFunctions) {
  75         m_staticFunctions = adoptPtr(new OpaqueJSClassStaticFunctionsTable);
  76         while (staticFunction->name) {
  77             String functionName = String::fromUTF8(staticFunction->name);
  78             if (!functionName.isNull())
  79                 m_staticFunctions->set(functionName.impl(), adoptPtr(new StaticFunctionEntry(staticFunction->callAsFunction, staticFunction->attributes)));
  80             ++staticFunction;
  81         }
  82     }
  83
  84     if (protoClass)
  85         prototypeClass = JSClassRetain(protoClass);
  86 }
  87
  88 OpaqueJSClass::~OpaqueJSClass()
  89 {
  90     // The empty string is shared across threads & is an identifier, in all other cases we should have done a deep copy in className(), below.
  91     ASSERT(!m_className.length() || !m_className.impl()->isIdentifier());
  92
  93 #ifndef NDEBUG
  94     if (m_staticValues) {
  95         OpaqueJSClassStaticValuesTable::const_iterator end = m_staticValues->end();
  96         for (OpaqueJSClassStaticValuesTable::const_iterator it = m_staticValues->begin(); it != end; ++it)
  97             ASSERT(!it->key->isIdentifier());
  98     }
  99
 100     if (m_staticFunctions) {
 101         OpaqueJSClassStaticFunctionsTable::const_iterator end = m_staticFunctions->end();
 102         for (OpaqueJSClassStaticFunctionsTable::const_iterator it = m_staticFunctions->begin(); it != end; ++it)
 103             ASSERT(!it->key->isIdentifier());
 104     }
 105 #endif
 106
 107     if (prototypeClass)
 108         JSClassRelease(prototypeClass);
 109 }
 110
 111 PassRefPtr<OpaqueJSClass> OpaqueJSClass::createNoAutomaticPrototype(const JSClassDefinition* definition)
 112 {
 113     return adoptRef(new OpaqueJSClass(definition, 0));
 114 }
 115
 116 PassRefPtr<OpaqueJSClass> OpaqueJSClass::create(const JSClassDefinition* clientDefinition)
 117 {
 118     JSClassDefinition definition = *clientDefinition; // Avoid modifying client copy.
 119
 120     JSClassDefinition protoDefinition = kJSClassDefinitionEmpty;
 121     protoDefinition.finalize = 0;
 122     swap(definition.staticFunctions, protoDefinition.staticFunctions); // Move static functions to the prototype.
 123
 124     // We are supposed to use JSClassRetain/Release but since we know that we currently have
 125     // the only reference to this class object we cheat and use a RefPtr instead.
 126     RefPtr<OpaqueJSClass> protoClass = adoptRef(new OpaqueJSClass(&protoDefinition, 0));
 127     return adoptRef(new OpaqueJSClass(&definition, protoClass.get()));
 128 }
 129
 130 OpaqueJSClassContextData::OpaqueJSClassContextData(JSC::VM&, OpaqueJSClass* jsClass)
 131     : m_class(jsClass)
 132 {
 133     if (jsClass->m_staticValues) {
 134         staticValues = adoptPtr(new OpaqueJSClassStaticValuesTable);
 135         OpaqueJSClassStaticValuesTable::const_iterator end = jsClass->m_staticValues->end();
 136         for (OpaqueJSClassStaticValuesTable::const_iterator it = jsClass->m_staticValues->begin(); it != end; ++it) {
 137             ASSERT(!it->key->isIdentifier());
 138             staticValues->add(it->key->isolatedCopy(), adoptPtr(new StaticValueEntry(it->value->getProperty, it->value->setProperty, it->value->attributes)));
 139         }
 140     }
 141
 142     if (jsClass->m_staticFunctions) {
 143         staticFunctions = adoptPtr(new OpaqueJSClassStaticFunctionsTable);
 144         OpaqueJSClassStaticFunctionsTable::const_iterator end = jsClass->m_staticFunctions->end();
 145         for (OpaqueJSClassStaticFunctionsTable::const_iterator it = jsClass->m_staticFunctions->begin(); it != end; ++it) {
 146             ASSERT(!it->key->isIdentifier());
 147             staticFunctions->add(it->key->isolatedCopy(), adoptPtr(new StaticFunctionEntry(it->value->callAsFunction, it->value->attributes)));
 148         }
 149     }
 150 }
 151
 152 OpaqueJSClassContextData& OpaqueJSClass::contextData(ExecState* exec)
 153 {
 154     OwnPtr<OpaqueJSClassContextData>& contextData = exec->lexicalGlobalObject()->opaqueJSClassData().add(this, nullptr).iterator->value;
 155     if (!contextData)
 156         contextData = adoptPtr(new OpaqueJSClassContextData(exec->vm(), this));
 157     return *contextData;
 158 }
 159
 160 String OpaqueJSClass::className()
 161 {
 162     // Make a deep copy, so that the caller has no chance to put the original into IdentifierTable.
 163     return m_className.isolatedCopy();
 164 }
 165
 166 OpaqueJSClassStaticValuesTable* OpaqueJSClass::staticValues(JSC::ExecState* exec)
 167 {
 168     return contextData(exec).staticValues.get();
 169 }
 170
 171 OpaqueJSClassStaticFunctionsTable* OpaqueJSClass::staticFunctions(JSC::ExecState* exec)
 172 {
 173     return contextData(exec).staticFunctions.get();
 174 }
 175
 176 /*!
 177 // Doc here in case we make this public. (Hopefully we won't.)
 178 @function
 179  @abstract Returns the prototype that will be used when constructing an object with a given class.
 180  @param ctx The execution context to use.
 181  @param jsClass A JSClass whose prototype you want to get.
 182  @result The JSObject prototype that was automatically generated for jsClass, or NULL if no prototype was automatically generated. This is the prototype that will be used when constructing an object using jsClass.
 183 */
 184 JSObject* OpaqueJSClass::prototype(ExecState* exec)
 185 {
 186     /* Class (C++) and prototype (JS) inheritance are parallel, so:
 187      *     (C++)      |        (JS)
 188      *   ParentClass  |   ParentClassPrototype
 189      *       ^        |          ^
 190      *       |        |          |
 191      *  DerivedClass  |  DerivedClassPrototype
 192      */
 193
 194     if (!prototypeClass)
 195         return 0;
 196
 197     OpaqueJSClassContextData& jsClassData = contextData(exec);
 198
 199     if (JSObject* prototype = jsClassData.cachedPrototype.get())
 200         return prototype;
 201
 202     // Recursive, but should be good enough for our purposes
 203     JSObject* prototype = JSCallbackObject<JSDestructibleObject>::create(exec, exec->lexicalGlobalObject(), exec->lexicalGlobalObject()->callbackObjectStructure(), prototypeClass, &jsClassData); // set jsClassData as the object's private data, so it can clear our reference on destruction
 204     if (parentClass) {
 205         if (JSObject* parentPrototype = parentClass->prototype(exec))
 206             prototype->setPrototype(exec->vm(), parentPrototype);
 207     }
 208
 209     jsClassData.cachedPrototype = PassWeak<JSObject>(prototype);
 210     return prototype;
 211 }