File: OpaqueJSString.cpp

package info (click to toggle)
webkit2gtk 2.48.3-1
  • links: PTS, VCS
  • area: main
  • in suites: sid, trixie
  • size: 429,620 kB
  • sloc: cpp: 3,696,936; javascript: 194,444; ansic: 169,997; python: 46,499; asm: 19,276; ruby: 18,528; perl: 16,602; xml: 4,650; yacc: 2,360; sh: 2,098; java: 1,993; lex: 1,327; pascal: 366; makefile: 298
file content (110 lines) | stat: -rw-r--r-- 3,481 bytes parent folder | download | duplicates (4)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
/*
 * Copyright (C) 2008-2019 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
 */

#include "config.h"
#include "OpaqueJSString.h"

#include "Identifier.h"
#include "IdentifierInlines.h"
#include <wtf/MallocSpan.h>
#include <wtf/text/StringView.h>

using namespace JSC;

RefPtr<OpaqueJSString> OpaqueJSString::tryCreate(const String& string)
{
    if (string.isNull())
        return nullptr;

    return adoptRef(new OpaqueJSString(string));
}

RefPtr<OpaqueJSString> OpaqueJSString::tryCreate(String&& string)
{
    if (string.isNull())
        return nullptr;

    return adoptRef(new OpaqueJSString(WTFMove(string)));
}

OpaqueJSString::~OpaqueJSString()
{
    // m_characters is put in a local here to avoid an extra atomic load.
    UChar* characters = m_characters;
    if (!characters)
        return;

    if (!m_string.is8Bit() && m_string.span16().data() == characters)
        return;

    fastFree(characters);
}

String OpaqueJSString::string() const
{
    // Return a copy of the wrapped string, because the caller may make it an Identifier.
    return m_string.isolatedCopy();
}

Identifier OpaqueJSString::identifier(VM* vm) const
{
    if (m_string.isNull())
        return Identifier();
    if (m_string.isEmpty())
        return Identifier(Identifier::EmptyIdentifier);
    if (m_string.is8Bit())
        return Identifier::fromString(*vm, m_string.span8());
    return Identifier::fromString(*vm, m_string.span16());
}

const UChar* OpaqueJSString::characters()
{
    // m_characters is put in a local here to avoid an extra atomic load.
    UChar* characters = m_characters;
    if (characters)
        return characters;

    if (m_string.isNull())
        return nullptr;

    auto newCharacters = MallocSpan<UChar>::malloc(m_string.length() * sizeof(UChar));
    StringView { m_string }.getCharacters(newCharacters.mutableSpan());

    if (!m_characters.compare_exchange_strong(characters, newCharacters.mutableSpan().data()))
        return characters;

    return newCharacters.leakSpan().data();
}

bool OpaqueJSString::equal(const OpaqueJSString* a, const OpaqueJSString* b)
{
    if (a == b)
        return true;

    if (!a || !b)
        return false;

    return a->m_string == b->m_string;
}