1/*
2 * Copyright (C) 2017 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#pragma once
27
28#include "DisallowScope.h"
29#include <wtf/ThreadSpecific.h>
30
31namespace JSC {
32
33class DisallowVMReentry : public DisallowScope<DisallowVMReentry> {
34 WTF_MAKE_NONCOPYABLE(DisallowVMReentry);
35 typedef DisallowScope<DisallowVMReentry> Base;
36public:
37#ifdef NDEBUG
38
39 ALWAYS_INLINE DisallowVMReentry(bool = false) { }
40 ALWAYS_INLINE static void initialize() { }
41
42#else // not NDEBUG
43
44 DisallowVMReentry(bool enabled = true)
45 : Base(enabled)
46 { }
47
48 static void initialize()
49 {
50 WTF::threadSpecificKeyCreate(&s_scopeReentryCount, 0);
51 }
52
53private:
54 static uintptr_t scopeReentryCount()
55 {
56 return reinterpret_cast<uintptr_t>(WTF::threadSpecificGet(s_scopeReentryCount));
57 }
58 static void setScopeReentryCount(uintptr_t value)
59 {
60 WTF::threadSpecificSet(s_scopeReentryCount, reinterpret_cast<void*>(value));
61 }
62
63 JS_EXPORT_PRIVATE static WTF::ThreadSpecificKey s_scopeReentryCount;
64
65#endif // NDEBUG
66
67 friend class DisallowScope<DisallowVMReentry>;
68};
69
70} // namespace JSC
71