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/ScopedPersistent.h" 30 #include "bindings/v8/UnsafePersistent.h" 31 #include <v8.h> 32 #include "wtf/HashMap.h" 33 #include "wtf/RefPtr.h" 34 #include "wtf/text/AtomicString.h" 35 #include "wtf/text/WTFString.h" 36 37 namespace WebCore { 38 39 class StringCache { 40 public: 41 StringCache() { } 42 43 v8::Handle<v8::String> v8ExternalString(StringImpl* stringImpl, v8::Isolate* isolate) 44 { 45 ASSERT(stringImpl); 46 if (m_lastStringImpl.get() == stringImpl) 47 return m_lastV8String.newLocal(isolate); 48 return v8ExternalStringSlow(stringImpl, isolate); 49 } 50 51 void setReturnValueFromString(v8::ReturnValue<v8::Value> returnValue, StringImpl* stringImpl) 52 { 53 ASSERT(stringImpl); 54 if (m_lastStringImpl.get() == stringImpl) 55 returnValue.Set(*m_lastV8String.persistent()); 56 else 57 setReturnValueFromStringSlow(returnValue, stringImpl); 58 } 59 60 private: 61 static void makeWeakCallback(v8::Isolate*, v8::Persistent<v8::String>*, StringImpl*); 62 63 v8::Handle<v8::String> v8ExternalStringSlow(StringImpl*, v8::Isolate*); 64 void setReturnValueFromStringSlow(v8::ReturnValue<v8::Value>, StringImpl*); 65 v8::Local<v8::String> createStringAndInsertIntoCache(StringImpl*, v8::Isolate*); 66 67 HashMap<StringImpl*, UnsafePersistent<v8::String> > m_stringCache; 68 UnsafePersistent<v8::String> m_lastV8String; 69 // Note: RefPtr is a must as we cache by StringImpl* equality, not identity 70 // hence lastStringImpl might be not a key of the cache (in sense of identity) 71 // and hence it's not refed on addition. 72 RefPtr<StringImpl> m_lastStringImpl; 73 }; 74 75 } // namespace WebCore 76 77 #endif // V8ValueCache_h 78