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#pragma once
30
31#include <limits>
32#include <unicode/utypes.h>
33#include <wtf/Assertions.h>
34#include <wtf/MallocPtr.h>
35
36namespace WTF {
37
38template <typename CharType>
39class StringBuffer {
40 WTF_MAKE_NONCOPYABLE(StringBuffer);
41 WTF_MAKE_FAST_ALLOCATED;
42public:
43 explicit StringBuffer(unsigned length)
44 : m_length(length)
45 , m_data(m_length ? static_cast<CharType*>(fastMalloc((Checked<size_t>(m_length) * sizeof(CharType)).unsafeGet())) : nullptr)
46 {
47 }
48
49 ~StringBuffer()
50 {
51 fastFree(m_data);
52 }
53
54 void shrink(unsigned newLength)
55 {
56 ASSERT(newLength <= m_length);
57 m_length = newLength;
58 }
59
60 void resize(unsigned newLength)
61 {
62 if (newLength > m_length) {
63 if (newLength > std::numeric_limits<unsigned>::max() / sizeof(UChar))
64 CRASH();
65 m_data = static_cast<UChar*>(fastRealloc(m_data, newLength * sizeof(UChar)));
66 }
67 m_length = newLength;
68 }
69
70 unsigned length() const { return m_length; }
71 CharType* characters() { return m_data; }
72
73 CharType& operator[](unsigned i) { ASSERT_WITH_SECURITY_IMPLICATION(i < m_length); return m_data[i]; }
74
75 MallocPtr<CharType> release()
76 {
77 CharType* data = m_data;
78 m_data = 0;
79 return adoptMallocPtr(data);
80 }
81
82private:
83 unsigned m_length;
84 CharType* m_data;
85};
86
87} // namespace WTF
88
89using WTF::StringBuffer;
90