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 "JSContextRef.h" 28#include "JSContextRefPrivate.h" 29 30#include "APICast.h" 31#include "InitializeThreading.h" 32#include "JSCallbackObject.h" 33#include "JSClassRef.h" 34#include "JSGlobalObject.h" 35#include "JSObject.h" 36#include <wtf/text/StringHash.h> 37 38#if OS(DARWIN) 39#include <mach-o/dyld.h> 40 41static const int32_t webkitFirstVersionWithConcurrentGlobalContexts = 0x2100500; // 528.5.0 42#endif 43 44using namespace JSC; 45 46JSContextGroupRef JSContextGroupCreate() 47{ 48 initializeThreading(); 49 return toRef(JSGlobalData::createContextGroup(ThreadStackTypeSmall).leakRef()); 50} 51 52JSContextGroupRef JSContextGroupRetain(JSContextGroupRef group) 53{ 54 toJS(group)->ref(); 55 return group; 56} 57 58void JSContextGroupRelease(JSContextGroupRef group) 59{ 60 toJS(group)->deref(); 61} 62 63JSGlobalContextRef JSGlobalContextCreate(JSClassRef globalObjectClass) 64{ 65 initializeThreading(); 66#if OS(DARWIN) 67 // When running on Tiger or Leopard, or if the application was linked before JSGlobalContextCreate was changed 68 // to use a unique JSGlobalData, we use a shared one for compatibility. 69#if !defined(BUILDING_ON_TIGER) && !defined(BUILDING_ON_LEOPARD) 70 if (NSVersionOfLinkTimeLibrary("JavaScriptCore") <= webkitFirstVersionWithConcurrentGlobalContexts) { 71#else 72 { 73#endif 74 JSLock lock(LockForReal); 75 return JSGlobalContextCreateInGroup(toRef(&JSGlobalData::sharedInstance()), globalObjectClass); 76 } 77#endif // OS(DARWIN) 78 79 return JSGlobalContextCreateInGroup(0, globalObjectClass); 80} 81 82JSGlobalContextRef JSGlobalContextCreateInGroup(JSContextGroupRef group, JSClassRef globalObjectClass) 83{ 84 initializeThreading(); 85 86 JSLock lock(LockForReal); 87 RefPtr<JSGlobalData> globalData = group ? PassRefPtr<JSGlobalData>(toJS(group)) : JSGlobalData::createContextGroup(ThreadStackTypeSmall); 88 89 APIEntryShim entryShim(globalData.get(), false); 90 91#if ENABLE(JSC_MULTIPLE_THREADS) 92 globalData->makeUsableFromMultipleThreads(); 93#endif 94 95 if (!globalObjectClass) { 96 JSGlobalObject* globalObject = new (globalData.get()) JSGlobalObject(*globalData); 97 return JSGlobalContextRetain(toGlobalRef(globalObject->globalExec())); 98 } 99 100 JSGlobalObject* globalObject = new (globalData.get()) JSCallbackObject<JSGlobalObject>(*globalData, globalObjectClass, JSCallbackObject<JSGlobalObject>::createStructure(*globalData, jsNull())); 101 ExecState* exec = globalObject->globalExec(); 102 JSValue prototype = globalObjectClass->prototype(exec); 103 if (!prototype) 104 prototype = jsNull(); 105 globalObject->resetPrototype(*globalData, prototype); 106 return JSGlobalContextRetain(toGlobalRef(exec)); 107} 108 109JSGlobalContextRef JSGlobalContextRetain(JSGlobalContextRef ctx) 110{ 111 ExecState* exec = toJS(ctx); 112 APIEntryShim entryShim(exec); 113 114 JSGlobalData& globalData = exec->globalData(); 115 gcProtect(exec->dynamicGlobalObject()); 116 globalData.ref(); 117 return ctx; 118} 119 120void JSGlobalContextRelease(JSGlobalContextRef ctx) 121{ 122 ExecState* exec = toJS(ctx); 123 JSLock lock(exec); 124 125 JSGlobalData& globalData = exec->globalData(); 126 JSGlobalObject* dgo = exec->dynamicGlobalObject(); 127 IdentifierTable* savedIdentifierTable = wtfThreadData().setCurrentIdentifierTable(globalData.identifierTable); 128 129 // One reference is held by JSGlobalObject, another added by JSGlobalContextRetain(). 130 bool releasingContextGroup = globalData.refCount() == 2; 131 bool releasingGlobalObject = Heap::heap(dgo)->unprotect(dgo); 132 // If this is the last reference to a global data, it should also 133 // be the only remaining reference to the global object too! 134 ASSERT(!releasingContextGroup || releasingGlobalObject); 135 136 // An API 'JSGlobalContextRef' retains two things - a global object and a 137 // global data (or context group, in API terminology). 138 // * If this is the last reference to any contexts in the given context group, 139 // call destroy on the heap (the global data is being freed). 140 // * If this was the last reference to the global object, then unprotecting 141 // it may release a lot of GC memory - run the garbage collector now. 142 // * If there are more references remaining the the global object, then do nothing 143 // (specifically that is more protects, which we assume come from other JSGlobalContextRefs). 144 if (releasingContextGroup) { 145 globalData.clearBuiltinStructures(); 146 globalData.heap.destroy(); 147 } else if (releasingGlobalObject) 148 globalData.heap.collectAllGarbage(); 149 150 globalData.deref(); 151 152 wtfThreadData().setCurrentIdentifierTable(savedIdentifierTable); 153} 154 155JSObjectRef JSContextGetGlobalObject(JSContextRef ctx) 156{ 157 ExecState* exec = toJS(ctx); 158 APIEntryShim entryShim(exec); 159 160 // It is necessary to call toThisObject to get the wrapper object when used with WebCore. 161 return toRef(exec->lexicalGlobalObject()->toThisObject(exec)); 162} 163 164JSContextGroupRef JSContextGetGroup(JSContextRef ctx) 165{ 166 ExecState* exec = toJS(ctx); 167 return toRef(&exec->globalData()); 168} 169 170JSGlobalContextRef JSContextGetGlobalContext(JSContextRef ctx) 171{ 172 ExecState* exec = toJS(ctx); 173 APIEntryShim entryShim(exec); 174 175 return toGlobalRef(exec->lexicalGlobalObject()->globalExec()); 176} 177