1 | // Copyright (C) 2019 The Qt Company Ltd. |
2 | // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only |
3 | |
4 | #ifndef QV4STRINGTOARRAYINDEX_P_H |
5 | #define QV4STRINGTOARRAYINDEX_P_H |
6 | |
7 | // |
8 | // W A R N I N G |
9 | // ------------- |
10 | // |
11 | // This file is not part of the Qt API. It exists purely as an |
12 | // implementation detail. This header file may change from version to |
13 | // version without notice, or even be removed. |
14 | // |
15 | // We mean it. |
16 | // |
17 | |
18 | #include <QtCore/private/qnumeric_p.h> |
19 | #include <QtCore/qstring.h> |
20 | #include <limits> |
21 | |
22 | QT_BEGIN_NAMESPACE |
23 | |
24 | namespace QV4 { |
25 | |
26 | inline uint charToUInt(const QChar *ch) { return ch->unicode(); } |
27 | inline uint charToUInt(const char *ch) { return static_cast<unsigned char>(*ch); } |
28 | |
29 | template <typename T> |
30 | uint stringToArrayIndex(const T *ch, const T *end) |
31 | { |
32 | if (ch == end) |
33 | return std::numeric_limits<uint>::max(); |
34 | uint i = charToUInt(ch) - '0'; |
35 | if (i > 9) |
36 | return std::numeric_limits<uint>::max(); |
37 | ++ch; |
38 | // reject "01", "001", ... |
39 | if (i == 0 && ch != end) |
40 | return std::numeric_limits<uint>::max(); |
41 | |
42 | while (ch < end) { |
43 | uint x = charToUInt(ch) - '0'; |
44 | if (x > 9) |
45 | return std::numeric_limits<uint>::max(); |
46 | if (qMulOverflow(v1: i, v2: uint(10), r: &i) || qAddOverflow(v1: i, v2: x, r: &i)) // i = i * 10 + x |
47 | return std::numeric_limits<uint>::max(); |
48 | ++ch; |
49 | } |
50 | return i; |
51 | } |
52 | |
53 | inline uint stringToArrayIndex(const QString &str) |
54 | { |
55 | return stringToArrayIndex(ch: str.constData(), end: str.constData() + str.size()); |
56 | } |
57 | |
58 | } // namespace QV4 |
59 | |
60 | QT_END_NAMESPACE |
61 | |
62 | #endif // QV4STRINGTOARRAYINDEX_P_H |
63 | |