1 /* 2 * Copyright (C) 2008, 2010 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 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of Apple Inc. ("Apple") nor the names of its 14 * contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY 18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 20 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY 21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 23 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 #ifndef StringBuffer_h 30 #define StringBuffer_h 31 32 #include "wtf/Assertions.h" 33 #include "wtf/text/StringImpl.h" 34 #include "wtf/unicode/Unicode.h" 35 36 namespace WTF { 37 38 template <typename CharType> 39 class StringBuffer { 40 WTF_MAKE_NONCOPYABLE(StringBuffer); 41 public: 42 StringBuffer() { } 43 44 explicit StringBuffer(unsigned length) 45 { 46 CharType* characters; 47 m_data = StringImpl::createUninitialized(length, characters); 48 } 49 50 ~StringBuffer() 51 { 52 } 53 54 void shrink(unsigned newLength) 55 { 56 if (m_data->length() == newLength) 57 return; 58 m_data->truncateAssumingIsolated(newLength); 59 } 60 61 void resize(unsigned newLength) 62 { 63 if (!m_data) { 64 CharType* characters; 65 m_data = StringImpl::createUninitialized(newLength, characters); 66 return; 67 } 68 if (newLength > m_data->length()) { 69 CharType* characters; 70 m_data = StringImpl::reallocate(m_data.release(), newLength, characters); 71 return; 72 } 73 shrink(newLength); 74 } 75 76 unsigned length() const { return m_data ? m_data->length() : 0; } 77 CharType* characters() { return length() ? const_cast<CharType*>(m_data->getCharacters<CharType>()) : 0; } 78 79 CharType& operator[](unsigned i) { ASSERT_WITH_SECURITY_IMPLICATION(i < length()); return characters()[i]; } 80 81 PassRefPtr<StringImpl> release() { return m_data.release(); } 82 83 private: 84 RefPtr<StringImpl> m_data; 85 }; 86 87 } // namespace WTF 88 89 using WTF::StringBuffer; 90 91 #endif // StringBuffer_h 92