]> git.saurik.com Git - apple/javascriptcore.git/blame - runtime/JSStringJoiner.cpp
JavaScriptCore-1097.13.tar.gz
[apple/javascriptcore.git] / runtime / JSStringJoiner.cpp
CommitLineData
6fe7ccc8
A
1/*
2 * Copyright (C) 2012 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 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 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#include "config.h"
27#include "JSStringJoiner.h"
28
29#include "ExceptionHelpers.h"
30#include "JSString.h"
31#include "ScopeChain.h"
32#include <wtf/text/StringImpl.h>
33
34
35namespace JSC {
36
37// The destination is 16bits, at least one string is 16 bits.
38static inline void appendStringToData(UChar*& data, const UString& string)
39{
40 if (string.isNull())
41 return;
42
43 unsigned length = string.length();
44 const StringImpl* stringImpl = string.impl();
45
46 if (stringImpl->is8Bit()) {
47 for (unsigned i = 0; i < length; ++i) {
48 *data = stringImpl->characters8()[i];
49 ++data;
50 }
51 } else {
52 for (unsigned i = 0; i < length; ++i) {
53 *data = stringImpl->characters16()[i];
54 ++data;
55 }
56 }
57}
58
59// If the destination is 8bits, we know every string has to be 8bit.
60static inline void appendStringToData(LChar*& data, const UString& string)
61{
62 if (string.isNull())
63 return;
64 ASSERT(string.is8Bit());
65
66 unsigned length = string.length();
67 const StringImpl* stringImpl = string.impl();
68
69 for (unsigned i = 0; i < length; ++i) {
70 *data = stringImpl->characters8()[i];
71 ++data;
72 }
73}
74
75template<typename CharacterType>
76static inline PassRefPtr<StringImpl> joinStrings(const Vector<UString>& strings, const UString& separator, unsigned outputLength)
77{
78 ASSERT(outputLength);
79
80 CharacterType* data;
81 RefPtr<StringImpl> outputStringImpl = StringImpl::tryCreateUninitialized(outputLength, data);
82 if (!outputStringImpl)
83 return PassRefPtr<StringImpl>();
84
85 const UString firstString = strings.first();
86 appendStringToData(data, firstString);
87
88 for (size_t i = 1; i < strings.size(); ++i) {
89 appendStringToData(data, separator);
90 appendStringToData(data, strings[i]);
91 }
92
93 ASSERT(data == (outputStringImpl->getCharacters<CharacterType>() + outputStringImpl->length()));
94 return outputStringImpl.release();
95}
96
97JSValue JSStringJoiner::build(ExecState* exec)
98{
99 if (!m_isValid)
100 return throwOutOfMemoryError(exec);
101
102 if (!m_strings.size())
103 return jsEmptyString(exec);
104
105 size_t separatorLength = m_separator.length();
106 // FIXME: add special cases of joinStrings() for (separatorLength == 0) and (separatorLength == 1).
107 ASSERT(m_strings.size() > 0);
108 size_t totalSeparactorsLength = separatorLength * (m_strings.size() - 1);
109 size_t outputStringSize = totalSeparactorsLength + m_cumulatedStringsLength;
110
111 if (!outputStringSize)
112 return jsEmptyString(exec);
113
114 RefPtr<StringImpl> outputStringImpl;
115 if (m_is8Bits)
116 outputStringImpl = joinStrings<LChar>(m_strings, m_separator, outputStringSize);
117 else
118 outputStringImpl = joinStrings<UChar>(m_strings, m_separator, outputStringSize);
119
120 if (!outputStringImpl)
121 return throwOutOfMemoryError(exec);
122
123 return JSString::create(exec->globalData(), outputStringImpl.release());
124}
125
126}