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 #ifndef V8ValueCache_h 27 #define V8ValueCache_h 28 29 #include "bindings/v8/V8PersistentValueMap.h" 30 #include <v8.h> 31 #include "wtf/HashMap.h" 32 #include "wtf/RefPtr.h" 33 #include "wtf/text/AtomicString.h" 34 #include "wtf/text/WTFString.h" 35 36 namespace WebCore { 37 38 class StringCacheMapTraits : public V8PersistentValueMapTraits<StringImpl*, v8::String, true> { 39 public: 40 // Weak traits: 41 typedef StringImpl WeakCallbackDataType; 42 typedef v8::PersistentValueMap<StringImpl*, v8::String, StringCacheMapTraits> MapType; 43 WeakCallbackParameter(MapType * map,StringImpl * key,v8::Local<v8::String> & value)44 static WeakCallbackDataType* WeakCallbackParameter( 45 MapType* map, StringImpl* key, v8::Local<v8::String>& value) { return key; } DisposeCallbackData(WeakCallbackDataType * callbackData)46 static void DisposeCallbackData(WeakCallbackDataType* callbackData) { } 47 48 static MapType* MapFromWeakCallbackData( 49 const v8::WeakCallbackData<v8::String, WeakCallbackDataType>&); 50 KeyFromWeakCallbackData(const v8::WeakCallbackData<v8::String,WeakCallbackDataType> & data)51 static StringImpl* KeyFromWeakCallbackData( 52 const v8::WeakCallbackData<v8::String, WeakCallbackDataType>& data) 53 { 54 return data.GetParameter(); 55 } 56 57 static void Dispose(v8::Isolate*, v8::UniquePersistent<v8::String> value, StringImpl* key); 58 }; 59 60 61 class StringCache { 62 public: StringCache(v8::Isolate * isolate)63 StringCache(v8::Isolate* isolate) : m_stringCache(isolate) { } 64 ~StringCache(); 65 v8ExternalString(StringImpl * stringImpl,v8::Isolate * isolate)66 v8::Handle<v8::String> v8ExternalString(StringImpl* stringImpl, v8::Isolate* isolate) 67 { 68 ASSERT(stringImpl); 69 if (m_lastStringImpl.get() == stringImpl) 70 return m_lastV8String.NewLocal(isolate); 71 return v8ExternalStringSlow(stringImpl, isolate); 72 } 73 setReturnValueFromString(v8::ReturnValue<v8::Value> returnValue,StringImpl * stringImpl)74 void setReturnValueFromString(v8::ReturnValue<v8::Value> returnValue, StringImpl* stringImpl) 75 { 76 ASSERT(stringImpl); 77 if (m_lastStringImpl.get() == stringImpl) 78 m_lastV8String.SetReturnValue(returnValue); 79 else 80 setReturnValueFromStringSlow(returnValue, stringImpl); 81 } 82 83 friend class StringCacheMapTraits; 84 85 private: 86 v8::Handle<v8::String> v8ExternalStringSlow(StringImpl*, v8::Isolate*); 87 void setReturnValueFromStringSlow(v8::ReturnValue<v8::Value>, StringImpl*); 88 v8::Local<v8::String> createStringAndInsertIntoCache(StringImpl*, v8::Isolate*); 89 void InvalidateLastString(); 90 91 StringCacheMapTraits::MapType m_stringCache; 92 StringCacheMapTraits::MapType::PersistentValueReference m_lastV8String; 93 94 // Note: RefPtr is a must as we cache by StringImpl* equality, not identity 95 // hence lastStringImpl might be not a key of the cache (in sense of identity) 96 // and hence it's not refed on addition. 97 RefPtr<StringImpl> m_lastStringImpl; 98 }; 99 100 } // namespace WebCore 101 102 #endif // V8ValueCache_h 103