1/*
2 * Copyright (C) 2008 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 "OpaqueJSString.h"
28
29#include "CallFrame.h"
30#include "Identifier.h"
31#include "IdentifierInlines.h"
32#include "JSGlobalObject.h"
33#include <wtf/text/StringView.h>
34
35using namespace JSC;
36
37RefPtr<OpaqueJSString> OpaqueJSString::tryCreate(const String& string)
38{
39 if (string.isNull())
40 return nullptr;
41
42 return adoptRef(new OpaqueJSString(string));
43}
44
45RefPtr<OpaqueJSString> OpaqueJSString::tryCreate(String&& string)
46{
47 if (string.isNull())
48 return nullptr;
49
50 return adoptRef(new OpaqueJSString(WTFMove(string)));
51}
52
53OpaqueJSString::~OpaqueJSString()
54{
55 // m_characters is put in a local here to avoid an extra atomic load.
56 UChar* characters = m_characters;
57 if (!characters)
58 return;
59
60 if (!m_string.is8Bit() && m_string.characters16() == characters)
61 return;
62
63 fastFree(characters);
64}
65
66String OpaqueJSString::string() const
67{
68 // Return a copy of the wrapped string, because the caller may make it an Identifier.
69 return m_string.isolatedCopy();
70}
71
72Identifier OpaqueJSString::identifier(VM* vm) const
73{
74 if (m_string.isNull())
75 return Identifier();
76
77 if (m_string.isEmpty())
78 return Identifier(Identifier::EmptyIdentifier);
79
80 if (m_string.is8Bit())
81 return Identifier::fromString(vm, m_string.characters8(), m_string.length());
82
83 return Identifier::fromString(vm, m_string.characters16(), m_string.length());
84}
85
86const UChar* OpaqueJSString::characters()
87{
88 // m_characters is put in a local here to avoid an extra atomic load.
89 UChar* characters = m_characters;
90 if (characters)
91 return characters;
92
93 if (m_string.isNull())
94 return nullptr;
95
96 unsigned length = m_string.length();
97 UChar* newCharacters = static_cast<UChar*>(fastMalloc(length * sizeof(UChar)));
98 StringView(m_string).getCharactersWithUpconvert(newCharacters);
99
100 if (!m_characters.compare_exchange_strong(characters, newCharacters)) {
101 fastFree(newCharacters);
102 return characters;
103 }
104
105 return newCharacters;
106}
107
108bool OpaqueJSString::equal(const OpaqueJSString* a, const OpaqueJSString* b)
109{
110 if (a == b)
111 return true;
112
113 if (!a || !b)
114 return false;
115
116 return a->m_string == b->m_string;
117}
118