1 /* 2 * Copyright (C) 2009 Google 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 INC. AND ITS CONTRIBUTORS ``AS IS'' 14 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 15 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS 17 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 18 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 19 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 20 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 21 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 22 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 23 * THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26 #include "config.h" 27 #include "bindings/core/v8/V8ValueCache.h" 28 29 #include "bindings/core/v8/V8Binding.h" 30 #include "wtf/text/StringHash.h" 31 32 namespace blink { 33 34 StringCacheMapTraits::MapType* StringCacheMapTraits::MapFromWeakCallbackData( 35 const v8::WeakCallbackData<v8::String, WeakCallbackDataType>& data) 36 { 37 return &(V8PerIsolateData::from(data.GetIsolate())->stringCache()->m_stringCache); 38 } 39 40 41 void StringCacheMapTraits::Dispose( 42 v8::Isolate* isolate, v8::UniquePersistent<v8::String> value, StringImpl* key) 43 { 44 V8PerIsolateData::from(isolate)->stringCache()->InvalidateLastString(); 45 key->deref(); 46 } 47 48 49 StringCache::~StringCache() 50 { 51 // The MapType::Dispose callback calls StringCache::InvalidateLastString, 52 // which will only work while the destructor has not yet finished. Thus, 53 // we need to clear the map before the destructor has completed. 54 m_stringCache.Clear(); 55 } 56 57 static v8::Local<v8::String> makeExternalString(const String& string, v8::Isolate* isolate) 58 { 59 if (string.is8Bit()) { 60 WebCoreStringResource8* stringResource = new WebCoreStringResource8(string); 61 v8::Local<v8::String> newString = v8::String::NewExternal(isolate, stringResource); 62 if (newString.IsEmpty()) 63 delete stringResource; 64 return newString; 65 } 66 67 WebCoreStringResource16* stringResource = new WebCoreStringResource16(string); 68 v8::Local<v8::String> newString = v8::String::NewExternal(isolate, stringResource); 69 if (newString.IsEmpty()) 70 delete stringResource; 71 return newString; 72 } 73 74 v8::Handle<v8::String> StringCache::v8ExternalStringSlow(StringImpl* stringImpl, v8::Isolate* isolate) 75 { 76 if (!stringImpl->length()) 77 return v8::String::Empty(isolate); 78 79 StringCacheMapTraits::MapType::PersistentValueReference cachedV8String = m_stringCache.GetReference(stringImpl); 80 if (!cachedV8String.IsEmpty()) { 81 m_lastStringImpl = stringImpl; 82 m_lastV8String = cachedV8String; 83 return m_lastV8String.NewLocal(isolate); 84 } 85 86 return createStringAndInsertIntoCache(stringImpl, isolate); 87 } 88 89 void StringCache::setReturnValueFromStringSlow(v8::ReturnValue<v8::Value> returnValue, StringImpl* stringImpl) 90 { 91 if (!stringImpl->length()) { 92 returnValue.SetEmptyString(); 93 return; 94 } 95 96 StringCacheMapTraits::MapType::PersistentValueReference cachedV8String = m_stringCache.GetReference(stringImpl); 97 if (!cachedV8String.IsEmpty()) { 98 m_lastStringImpl = stringImpl; 99 m_lastV8String = cachedV8String; 100 m_lastV8String.SetReturnValue(returnValue); 101 return; 102 } 103 104 returnValue.Set(createStringAndInsertIntoCache(stringImpl, returnValue.GetIsolate())); 105 } 106 107 v8::Local<v8::String> StringCache::createStringAndInsertIntoCache(StringImpl* stringImpl, v8::Isolate* isolate) 108 { 109 ASSERT(!m_stringCache.Contains(stringImpl)); 110 ASSERT(stringImpl->length()); 111 112 v8::Local<v8::String> newString = makeExternalString(String(stringImpl), isolate); 113 if (newString.IsEmpty()) 114 return newString; 115 116 v8::UniquePersistent<v8::String> wrapper(isolate, newString); 117 118 stringImpl->ref(); 119 wrapper.MarkIndependent(); 120 m_stringCache.Set(stringImpl, wrapper.Pass(), &m_lastV8String); 121 m_lastStringImpl = stringImpl; 122 123 return newString; 124 } 125 126 void StringCache::InvalidateLastString() 127 { 128 m_lastStringImpl = nullptr; 129 m_lastV8String.Reset(); 130 } 131 132 } // namespace blink 133