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
111
112
113
114
115
116
117
118
119
|
/*
* Copyright (C) 2025 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. AND ITS CONTRIBUTORS ``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 ITS 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.
*/
#pragma once
#include <JavaScriptCore/JSRetainPtr.h>
#include <JavaScriptCore/JSValueRef.h>
#include <wtf/HashTraits.h>
namespace WebKit {
template<typename T>
class Protected {
public:
Protected() = default;
Protected(JSGlobalContextRef context, T value)
: m_context(context)
, m_value(value)
{
ASSERT(context);
ASSERT(value);
protectIfNonNull();
}
Protected(Protected&& other) { moveFrom(WTFMove(other)); }
Protected(const Protected& other) { copyFrom(other); }
Protected& operator=(Protected&& other)
{
moveFrom(WTFMove(other));
return *this;
}
Protected& operator=(const Protected& other)
{
copyFrom(other);
return *this;
}
~Protected() { unprotectIfNonNull(); }
T get() const { return m_value; }
explicit operator bool() const { return !!m_value; }
bool operator==(const Protected& other) const { return m_value == other.m_value; }
Protected(WTF::HashTableDeletedValueType)
: m_value(reinterpret_cast<T>(-1)) { }
bool isHashTableDeletedValue() const { return m_value == reinterpret_cast<T>(-1); }
private:
void moveFrom(Protected&& other)
{
unprotectIfNonNull();
m_context = std::exchange(other.m_context, nullptr);
m_value = std::exchange(other.m_value, nullptr);
}
void copyFrom(const Protected& other)
{
unprotectIfNonNull();
m_context = other.m_context;
m_value = other.m_value;
protectIfNonNull();
}
void protectIfNonNull()
{
if (m_value)
JSValueProtect(m_context.get(), m_value);
}
void unprotectIfNonNull()
{
if (T value = std::exchange(m_value, nullptr))
JSValueUnprotect(m_context.get(), value);
m_context = nullptr;
}
JSRetainPtr<JSGlobalContextRef> m_context;
T m_value { nullptr };
};
}
namespace WTF {
template<typename T> struct HashTraits<WebKit::Protected<T>> : SimpleClassHashTraits<WebKit::Protected<T>> { };
template<typename T> struct DefaultHash<WebKit::Protected<T>> {
static unsigned hash(const WebKit::Protected<T>& key) { return IntHash<uintptr_t>::hash(reinterpret_cast<uintptr_t>(key.get())); }
static bool equal(const WebKit::Protected<T>& a, const WebKit::Protected<T>& b) { return a.get() == b.get(); }
static constexpr bool safeToCompareToEmptyOrDeleted = true;
};
}
|
