1/*
2 * Copyright (C) 2015 Yusuke Suzuki <utatane.tea@gmail.com>.
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. AND ITS CONTRIBUTORS ``AS IS''
14 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
15 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
17 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
18 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
19 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
20 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
21 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
22 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
23 * THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#ifndef UniquedStringImpl_h
27#define UniquedStringImpl_h
28
29#include <wtf/text/StringImpl.h>
30
31namespace WTF {
32
33// It represents that the string impl is uniqued in some ways.
34// When the given 2 string impls are both uniqued string impls, we can compare it just using pointer comparison.
35class UniquedStringImpl : public StringImpl {
36private:
37 UniquedStringImpl() = delete;
38};
39
40#if !ASSERT_DISABLED
41// UniquedStringImpls created from StaticASCIILiteral will ASSERT
42// in the generic ValueCheck<T>::checkConsistency
43// as they are not allocated by fastMalloc.
44// We don't currently have any way to detect that case
45// so we ignore the consistency check for all UniquedStringImpls*.
46template<> struct
47ValueCheck<UniquedStringImpl*> {
48 static void checkConsistency(const UniquedStringImpl*) { }
49};
50
51template<> struct
52ValueCheck<const UniquedStringImpl*> {
53 static void checkConsistency(const UniquedStringImpl*) { }
54};
55#endif
56
57} // namespace WTF
58
59using WTF::UniquedStringImpl;
60
61#endif // UniquedStringImpl_h
62