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39
40#ifndef QV4STRINGTOARRAYINDEX_P_H
41#define QV4STRINGTOARRAYINDEX_P_H
42
43//
44// W A R N I N G
45// -------------
46//
47// This file is not part of the Qt API. It exists purely as an
48// implementation detail. This header file may change from version to
49// version without notice, or even be removed.
50//
51// We mean it.
52//
53
54#include <QtCore/private/qnumeric_p.h>
55#include <QtCore/qstring.h>
56#include <limits>
57
58QT_BEGIN_NAMESPACE
59
60namespace QV4 {
61
62inline uint charToUInt(const QChar *ch) { return ch->unicode(); }
63inline uint charToUInt(const char *ch) { return static_cast<unsigned char>(*ch); }
64
65template <typename T>
66uint stringToArrayIndex(const T *ch, const T *end)
67{
68 uint i = charToUInt(ch) - '0';
69 if (i > 9)
70 return std::numeric_limits<uint>::max();
71 ++ch;
72 // reject "01", "001", ...
73 if (i == 0 && ch != end)
74 return std::numeric_limits<uint>::max();
75
76 while (ch < end) {
77 uint x = charToUInt(ch) - '0';
78 if (x > 9)
79 return std::numeric_limits<uint>::max();
80 if (mul_overflow(v1: i, v2: uint(10), r: &i) || add_overflow(v1: i, v2: x, r: &i)) // i = i * 10 + x
81 return std::numeric_limits<uint>::max();
82 ++ch;
83 }
84 return i;
85}
86
87inline uint stringToArrayIndex(const QString &str)
88{
89 return stringToArrayIndex(ch: str.constData(), end: str.constData() + str.length());
90}
91
92} // namespace QV4
93
94QT_END_NAMESPACE
95
96#endif // QV4STRINGTOARRAYINDEX_P_H
97

source code of qtdeclarative/src/qml/common/qv4stringtoarrayindex_p.h