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 "JSCallbackObject.h"
  31 #include "JSObjectRef.h"
  32 #include <runtime/InitializeThreading.h>
  33 #include <runtime/JSGlobalObject.h>
  34 #include <runtime/ObjectPrototype.h>
  35 #include <runtime/Identifier.h>
  36 #include <wtf/text/StringHash.h>
  37 #include <wtf/unicode/UTF8.h>
  38
  39 using namespace std;
  40 using namespace JSC;
  41 using namespace WTF::Unicode;
  42
  43 const JSClassDefinition kJSClassDefinitionEmpty = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
  44
  45 static inline UString tryCreateStringFromUTF8(const char* string)
  46 {
  47     if (!string)
  48         return UString::null();
  49
  50     size_t length = strlen(string);
  51     Vector<UChar, 1024> buffer(length);
  52     UChar* p = buffer.data();
  53     if (conversionOK != convertUTF8ToUTF16(&string, string + length, &p, p + length))
  54         return UString::null();
  55
  56     return UString(buffer.data(), p - buffer.data());
  57 }
  58
  59 OpaqueJSClass::OpaqueJSClass(const JSClassDefinition* definition, OpaqueJSClass* protoClass)
  60     : parentClass(definition->parentClass)
  61     , prototypeClass(0)
  62     , initialize(definition->initialize)
  63     , finalize(definition->finalize)
  64     , hasProperty(definition->hasProperty)
  65     , getProperty(definition->getProperty)
  66     , setProperty(definition->setProperty)
  67     , deleteProperty(definition->deleteProperty)
  68     , getPropertyNames(definition->getPropertyNames)
  69     , callAsFunction(definition->callAsFunction)
  70     , callAsConstructor(definition->callAsConstructor)
  71     , hasInstance(definition->hasInstance)
  72     , convertToType(definition->convertToType)
  73     , m_className(tryCreateStringFromUTF8(definition->className))
  74     , m_staticValues(0)
  75     , m_staticFunctions(0)
  76 {
  77     initializeThreading();
  78
  79     if (const JSStaticValue* staticValue = definition->staticValues) {
  80         m_staticValues = new OpaqueJSClassStaticValuesTable();
  81         while (staticValue->name) {
  82             UString valueName = tryCreateStringFromUTF8(staticValue->name);
  83             if (!valueName.isNull()) {
  84                 // Use a local variable here to sidestep an RVCT compiler bug.
  85                 StaticValueEntry* entry = new StaticValueEntry(staticValue->getProperty, staticValue->setProperty, staticValue->attributes);
  86                 UStringImpl* impl = valueName.rep();
  87                 impl->ref();
  88                 m_staticValues->add(impl, entry);
  89             }
  90             ++staticValue;
  91         }
  92     }
  93
  94     if (const JSStaticFunction* staticFunction = definition->staticFunctions) {
  95         m_staticFunctions = new OpaqueJSClassStaticFunctionsTable();
  96         while (staticFunction->name) {
  97             UString functionName = tryCreateStringFromUTF8(staticFunction->name);
  98             if (!functionName.isNull()) {
  99                 // Use a local variable here to sidestep an RVCT compiler bug.
 100                 StaticFunctionEntry* entry = new StaticFunctionEntry(staticFunction->callAsFunction, staticFunction->attributes);
 101                 UStringImpl* impl = functionName.rep();
 102                 impl->ref();
 103                 m_staticFunctions->add(impl, entry);
 104             }
 105             ++staticFunction;
 106         }
 107     }
 108
 109     if (protoClass)
 110         prototypeClass = JSClassRetain(protoClass);
 111 }
 112
 113 OpaqueJSClass::~OpaqueJSClass()
 114 {
 115     // The empty string is shared across threads & is an identifier, in all other cases we should have done a deep copy in className(), below.
 116     ASSERT(!m_className.size() || !m_className.rep()->isIdentifier());
 117
 118     if (m_staticValues) {
 119         OpaqueJSClassStaticValuesTable::const_iterator end = m_staticValues->end();
 120         for (OpaqueJSClassStaticValuesTable::const_iterator it = m_staticValues->begin(); it != end; ++it) {
 121             ASSERT(!it->first->isIdentifier());
 122             delete it->second;
 123         }
 124         delete m_staticValues;
 125     }
 126
 127     if (m_staticFunctions) {
 128         OpaqueJSClassStaticFunctionsTable::const_iterator end = m_staticFunctions->end();
 129         for (OpaqueJSClassStaticFunctionsTable::const_iterator it = m_staticFunctions->begin(); it != end; ++it) {
 130             ASSERT(!it->first->isIdentifier());
 131             delete it->second;
 132         }
 133         delete m_staticFunctions;
 134     }
 135
 136     if (prototypeClass)
 137         JSClassRelease(prototypeClass);
 138 }
 139
 140 PassRefPtr<OpaqueJSClass> OpaqueJSClass::createNoAutomaticPrototype(const JSClassDefinition* definition)
 141 {
 142     return adoptRef(new OpaqueJSClass(definition, 0));
 143 }
 144
 145 static void clearReferenceToPrototype(JSObjectRef prototype)
 146 {
 147     OpaqueJSClassContextData* jsClassData = static_cast<OpaqueJSClassContextData*>(JSObjectGetPrivate(prototype));
 148     ASSERT(jsClassData);
 149     jsClassData->cachedPrototype.clear(toJS(prototype));
 150 }
 151
 152 PassRefPtr<OpaqueJSClass> OpaqueJSClass::create(const JSClassDefinition* clientDefinition)
 153 {
 154     JSClassDefinition definition = *clientDefinition; // Avoid modifying client copy.
 155
 156     JSClassDefinition protoDefinition = kJSClassDefinitionEmpty;
 157     protoDefinition.finalize = clearReferenceToPrototype;
 158     swap(definition.staticFunctions, protoDefinition.staticFunctions); // Move static functions to the prototype.
 159
 160     // We are supposed to use JSClassRetain/Release but since we know that we currently have
 161     // the only reference to this class object we cheat and use a RefPtr instead.
 162     RefPtr<OpaqueJSClass> protoClass = adoptRef(new OpaqueJSClass(&protoDefinition, 0));
 163     return adoptRef(new OpaqueJSClass(&definition, protoClass.get()));
 164 }
 165
 166 OpaqueJSClassContextData::OpaqueJSClassContextData(OpaqueJSClass* jsClass)
 167     : m_class(jsClass)
 168 {
 169     if (jsClass->m_staticValues) {
 170         staticValues = new OpaqueJSClassStaticValuesTable;
 171         OpaqueJSClassStaticValuesTable::const_iterator end = jsClass->m_staticValues->end();
 172         for (OpaqueJSClassStaticValuesTable::const_iterator it = jsClass->m_staticValues->begin(); it != end; ++it) {
 173             ASSERT(!it->first->isIdentifier());
 174             // Use a local variable here to sidestep an RVCT compiler bug.
 175             StaticValueEntry* entry = new StaticValueEntry(it->second->getProperty, it->second->setProperty, it->second->attributes);
 176             staticValues->add(UString::Rep::create(it->first->characters(), it->first->length()), entry);
 177         }
 178     } else
 179         staticValues = 0;
 180
 181     if (jsClass->m_staticFunctions) {
 182         staticFunctions = new OpaqueJSClassStaticFunctionsTable;
 183         OpaqueJSClassStaticFunctionsTable::const_iterator end = jsClass->m_staticFunctions->end();
 184         for (OpaqueJSClassStaticFunctionsTable::const_iterator it = jsClass->m_staticFunctions->begin(); it != end; ++it) {
 185             ASSERT(!it->first->isIdentifier());
 186             // Use a local variable here to sidestep an RVCT compiler bug.
 187             StaticFunctionEntry* entry = new StaticFunctionEntry(it->second->callAsFunction, it->second->attributes);
 188             staticFunctions->add(UString::Rep::create(it->first->characters(), it->first->length()), entry);
 189         }
 190
 191     } else
 192         staticFunctions = 0;
 193 }
 194
 195 OpaqueJSClassContextData::~OpaqueJSClassContextData()
 196 {
 197     if (staticValues) {
 198         deleteAllValues(*staticValues);
 199         delete staticValues;
 200     }
 201
 202     if (staticFunctions) {
 203         deleteAllValues(*staticFunctions);
 204         delete staticFunctions;
 205     }
 206 }
 207
 208 OpaqueJSClassContextData& OpaqueJSClass::contextData(ExecState* exec)
 209 {
 210     OpaqueJSClassContextData*& contextData = exec->globalData().opaqueJSClassData.add(this, 0).first->second;
 211     if (!contextData)
 212         contextData = new OpaqueJSClassContextData(this);
 213     return *contextData;
 214 }
 215
 216 UString OpaqueJSClass::className()
 217 {
 218     // Make a deep copy, so that the caller has no chance to put the original into IdentifierTable.
 219     return UString(m_className.data(), m_className.size());
 220 }
 221
 222 OpaqueJSClassStaticValuesTable* OpaqueJSClass::staticValues(JSC::ExecState* exec)
 223 {
 224     OpaqueJSClassContextData& jsClassData = contextData(exec);
 225     return jsClassData.staticValues;
 226 }
 227
 228 OpaqueJSClassStaticFunctionsTable* OpaqueJSClass::staticFunctions(JSC::ExecState* exec)
 229 {
 230     OpaqueJSClassContextData& jsClassData = contextData(exec);
 231     return jsClassData.staticFunctions;
 232 }
 233
 234 /*!
 235 // Doc here in case we make this public. (Hopefully we won't.)
 236 @function
 237  @abstract Returns the prototype that will be used when constructing an object with a given class.
 238  @param ctx The execution context to use.
 239  @param jsClass A JSClass whose prototype you want to get.
 240  @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.
 241 */
 242 JSObject* OpaqueJSClass::prototype(ExecState* exec)
 243 {
 244     /* Class (C++) and prototype (JS) inheritance are parallel, so:
 245      *     (C++)      |        (JS)
 246      *   ParentClass  |   ParentClassPrototype
 247      *       ^        |          ^
 248      *       |        |          |
 249      *  DerivedClass  |  DerivedClassPrototype
 250      */
 251
 252     if (!prototypeClass)
 253         return 0;
 254
 255     OpaqueJSClassContextData& jsClassData = contextData(exec);
 256
 257     if (!jsClassData.cachedPrototype) {
 258         // Recursive, but should be good enough for our purposes
 259         jsClassData.cachedPrototype = new (exec) JSCallbackObject<JSObject>(exec, exec->lexicalGlobalObject()->callbackObjectStructure(), prototypeClass, &jsClassData); // set jsClassData as the object's private data, so it can clear our reference on destruction
 260         if (parentClass) {
 261             if (JSObject* prototype = parentClass->prototype(exec))
 262                 jsClassData.cachedPrototype->setPrototype(prototype);
 263         }
 264     }
 265     return jsClassData.cachedPrototype.get();
 266 }