wtf/text/CString.cpp

   1 /*
   2  * Copyright (C) 2003, 2006, 2008, 2009, 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  * 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
  27 #include "config.h"
  28 #include "CString.h"
  29
  30 using namespace std;
  31
  32 namespace WTF {
  33
  34 CString::CString(const char* str)
  35 {
  36     init(str, strlen(str));
  37 }
  38
  39 CString::CString(const char* str, unsigned length)
  40 {
  41     init(str, length);
  42 }
  43
  44 void CString::init(const char* str, unsigned length)
  45 {
  46     if (!str)
  47         return;
  48
  49     if (length >= numeric_limits<size_t>::max())
  50         CRASH();
  51
  52     m_buffer = CStringBuffer::create(length + 1);
  53     memcpy(m_buffer->mutableData(), str, length);
  54     m_buffer->mutableData()[length] = '\0';
  55 }
  56
  57 char* CString::mutableData()
  58 {
  59     copyBufferIfNeeded();
  60     if (!m_buffer)
  61         return 0;
  62     return m_buffer->mutableData();
  63 }
  64
  65 CString CString::newUninitialized(size_t length, char*& characterBuffer)
  66 {
  67     if (length >= numeric_limits<size_t>::max())
  68         CRASH();
  69
  70     CString result;
  71     result.m_buffer = CStringBuffer::create(length + 1);
  72     char* bytes = result.m_buffer->mutableData();
  73     bytes[length] = '\0';
  74     characterBuffer = bytes;
  75     return result;
  76 }
  77
  78 void CString::copyBufferIfNeeded()
  79 {
  80     if (!m_buffer || m_buffer->hasOneRef())
  81         return;
  82
  83     RefPtr<CStringBuffer> buffer = m_buffer.release();
  84     size_t length = buffer->length();
  85     m_buffer = CStringBuffer::create(length);
  86     memcpy(m_buffer->mutableData(), buffer->data(), length);
  87 }
  88
  89 bool operator==(const CString& a, const CString& b)
  90 {
  91     if (a.isNull() != b.isNull())
  92         return false;
  93     if (a.length() != b.length())
  94         return false;
  95     return !strncmp(a.data(), b.data(), min(a.length(), b.length()));
  96 }
  97
  98 } // namespace WTF