Coverage Report

Created: 2025-01-28 06:34

/src/qtbase/src/3rdparty/double-conversion/double-conversion/string-to-double.h
Line
Count
Source (jump to first uncovered line)
1
// Copyright 2012 the V8 project authors. All rights reserved.
2
// Redistribution and use in source and binary forms, with or without
3
// modification, are permitted provided that the following conditions are
4
// met:
5
//
6
//     * Redistributions of source code must retain the above copyright
7
//       notice, this list of conditions and the following disclaimer.
8
//     * Redistributions in binary form must reproduce the above
9
//       copyright notice, this list of conditions and the following
10
//       disclaimer in the documentation and/or other materials provided
11
//       with the distribution.
12
//     * Neither the name of Google Inc. nor the names of its
13
//       contributors may be used to endorse or promote products derived
14
//       from this software without specific prior written permission.
15
//
16
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
28
#ifndef DOUBLE_CONVERSION_STRING_TO_DOUBLE_H_
29
#define DOUBLE_CONVERSION_STRING_TO_DOUBLE_H_
30
31
#include "utils.h"
32
33
namespace double_conversion {
34
35
class StringToDoubleConverter {
36
 public:
37
  // Enumeration for allowing octals and ignoring junk when converting
38
  // strings to numbers.
39
  enum Flags {
40
    NO_FLAGS = 0,
41
    ALLOW_HEX = 1,
42
    ALLOW_OCTALS = 2,
43
    ALLOW_TRAILING_JUNK = 4,
44
    ALLOW_LEADING_SPACES = 8,
45
    ALLOW_TRAILING_SPACES = 16,
46
    ALLOW_SPACES_AFTER_SIGN = 32,
47
    ALLOW_CASE_INSENSITIVITY = 64,
48
    ALLOW_CASE_INSENSIBILITY = 64,  // Deprecated
49
    ALLOW_HEX_FLOATS = 128,
50
  };
51
52
  static const uc16 kNoSeparator = '\0';
53
54
  // Flags should be a bit-or combination of the possible Flags-enum.
55
  //  - NO_FLAGS: no special flags.
56
  //  - ALLOW_HEX: recognizes the prefix "0x". Hex numbers may only be integers.
57
  //      Ex: StringToDouble("0x1234") -> 4660.0
58
  //          In StringToDouble("0x1234.56") the characters ".56" are trailing
59
  //          junk. The result of the call is hence dependent on
60
  //          the ALLOW_TRAILING_JUNK flag and/or the junk value.
61
  //      With this flag "0x" is a junk-string. Even with ALLOW_TRAILING_JUNK,
62
  //      the string will not be parsed as "0" followed by junk.
63
  //
64
  //  - ALLOW_OCTALS: recognizes the prefix "0" for octals:
65
  //      If a sequence of octal digits starts with '0', then the number is
66
  //      read as octal integer. Octal numbers may only be integers.
67
  //      Ex: StringToDouble("01234") -> 668.0
68
  //          StringToDouble("012349") -> 12349.0  // Not a sequence of octal
69
  //                                               // digits.
70
  //          In StringToDouble("01234.56") the characters ".56" are trailing
71
  //          junk. The result of the call is hence dependent on
72
  //          the ALLOW_TRAILING_JUNK flag and/or the junk value.
73
  //          In StringToDouble("01234e56") the characters "e56" are trailing
74
  //          junk, too.
75
  //  - ALLOW_TRAILING_JUNK: ignore trailing characters that are not part of
76
  //      a double literal.
77
  //  - ALLOW_LEADING_SPACES: skip over leading whitespace, including spaces,
78
  //                          new-lines, and tabs.
79
  //  - ALLOW_TRAILING_SPACES: ignore trailing whitespace.
80
  //  - ALLOW_SPACES_AFTER_SIGN: ignore whitespace after the sign.
81
  //       Ex: StringToDouble("-   123.2") -> -123.2.
82
  //           StringToDouble("+   123.2") -> 123.2
83
  //  - ALLOW_CASE_INSENSITIVITY: ignore case of characters for special values:
84
  //      infinity and nan.
85
  //  - ALLOW_HEX_FLOATS: allows hexadecimal float literals.
86
  //      This *must* start with "0x" and separate the exponent with "p".
87
  //      Examples: 0x1.2p3 == 9.0
88
  //                0x10.1p0 == 16.0625
89
  //      ALLOW_HEX and ALLOW_HEX_FLOATS are indented.
90
  //
91
  // empty_string_value is returned when an empty string is given as input.
92
  // If ALLOW_LEADING_SPACES or ALLOW_TRAILING_SPACES are set, then a string
93
  // containing only spaces is converted to the 'empty_string_value', too.
94
  //
95
  // junk_string_value is returned when
96
  //  a) ALLOW_TRAILING_JUNK is not set, and a junk character (a character not
97
  //     part of a double-literal) is found.
98
  //  b) ALLOW_TRAILING_JUNK is set, but the string does not start with a
99
  //     double literal.
100
  //
101
  // infinity_symbol and nan_symbol are strings that are used to detect
102
  // inputs that represent infinity and NaN. They can be null, in which case
103
  // they are ignored.
104
  // The conversion routine first reads any possible signs. Then it compares the
105
  // following character of the input-string with the first character of
106
  // the infinity, and nan-symbol. If either matches, the function assumes, that
107
  // a match has been found, and expects the following input characters to match
108
  // the remaining characters of the special-value symbol.
109
  // This means that the following restrictions apply to special-value symbols:
110
  //  - they must not start with signs ('+', or '-'),
111
  //  - they must not have the same first character.
112
  //  - they must not start with digits.
113
  //
114
  // If the separator character is not kNoSeparator, then that specific
115
  // character is ignored when in between two valid digits of the significant.
116
  // It is not allowed to appear in the exponent.
117
  // It is not allowed to lead or trail the number.
118
  // It is not allowed to appear twice next to each other.
119
  //
120
  // Examples:
121
  //  flags = ALLOW_HEX | ALLOW_TRAILING_JUNK,
122
  //  empty_string_value = 0.0,
123
  //  junk_string_value = NaN,
124
  //  infinity_symbol = "infinity",
125
  //  nan_symbol = "nan":
126
  //    StringToDouble("0x1234") -> 4660.0.
127
  //    StringToDouble("0x1234K") -> 4660.0.
128
  //    StringToDouble("") -> 0.0  // empty_string_value.
129
  //    StringToDouble(" ") -> NaN  // junk_string_value.
130
  //    StringToDouble(" 1") -> NaN  // junk_string_value.
131
  //    StringToDouble("0x") -> NaN  // junk_string_value.
132
  //    StringToDouble("-123.45") -> -123.45.
133
  //    StringToDouble("--123.45") -> NaN  // junk_string_value.
134
  //    StringToDouble("123e45") -> 123e45.
135
  //    StringToDouble("123E45") -> 123e45.
136
  //    StringToDouble("123e+45") -> 123e45.
137
  //    StringToDouble("123E-45") -> 123e-45.
138
  //    StringToDouble("123e") -> 123.0  // trailing junk ignored.
139
  //    StringToDouble("123e-") -> 123.0  // trailing junk ignored.
140
  //    StringToDouble("+NaN") -> NaN  // NaN string literal.
141
  //    StringToDouble("-infinity") -> -inf.  // infinity literal.
142
  //    StringToDouble("Infinity") -> NaN  // junk_string_value.
143
  //
144
  //  flags = ALLOW_OCTAL | ALLOW_LEADING_SPACES,
145
  //  empty_string_value = 0.0,
146
  //  junk_string_value = NaN,
147
  //  infinity_symbol = NULL,
148
  //  nan_symbol = NULL:
149
  //    StringToDouble("0x1234") -> NaN  // junk_string_value.
150
  //    StringToDouble("01234") -> 668.0.
151
  //    StringToDouble("") -> 0.0  // empty_string_value.
152
  //    StringToDouble(" ") -> 0.0  // empty_string_value.
153
  //    StringToDouble(" 1") -> 1.0
154
  //    StringToDouble("0x") -> NaN  // junk_string_value.
155
  //    StringToDouble("0123e45") -> NaN  // junk_string_value.
156
  //    StringToDouble("01239E45") -> 1239e45.
157
  //    StringToDouble("-infinity") -> NaN  // junk_string_value.
158
  //    StringToDouble("NaN") -> NaN  // junk_string_value.
159
  //
160
  //  flags = NO_FLAGS,
161
  //  separator = ' ':
162
  //    StringToDouble("1 2 3 4") -> 1234.0
163
  //    StringToDouble("1  2") -> NaN // junk_string_value
164
  //    StringToDouble("1 000 000.0") -> 1000000.0
165
  //    StringToDouble("1.000 000") -> 1.0
166
  //    StringToDouble("1.0e1 000") -> NaN // junk_string_value
167
  StringToDoubleConverter(int flags,
168
                          double empty_string_value,
169
                          double junk_string_value,
170
                          const char* infinity_symbol,
171
                          const char* nan_symbol,
172
                          uc16 separator = kNoSeparator)
173
0
      : flags_(flags),
174
0
        empty_string_value_(empty_string_value),
175
0
        junk_string_value_(junk_string_value),
176
0
        infinity_symbol_(infinity_symbol),
177
0
        nan_symbol_(nan_symbol),
178
0
        separator_(separator) {
179
0
  }
180
181
  // Performs the conversion.
182
  // The output parameter 'processed_characters_count' is set to the number
183
  // of characters that have been processed to read the number.
184
  // Spaces than are processed with ALLOW_{LEADING|TRAILING}_SPACES are included
185
  // in the 'processed_characters_count'. Trailing junk is never included.
186
  double StringToDouble(const char* buffer,
187
                        int length,
188
                        int* processed_characters_count) const;
189
190
  // Same as StringToDouble above but for 16 bit characters.
191
  double StringToDouble(const uc16* buffer,
192
                        int length,
193
                        int* processed_characters_count) const;
194
195
  // Same as StringToDouble but reads a float.
196
  // Note that this is not equivalent to static_cast<float>(StringToDouble(...))
197
  // due to potential double-rounding.
198
  float StringToFloat(const char* buffer,
199
                      int length,
200
                      int* processed_characters_count) const;
201
202
  // Same as StringToFloat above but for 16 bit characters.
203
  float StringToFloat(const uc16* buffer,
204
                      int length,
205
                      int* processed_characters_count) const;
206
207
  // Same as StringToDouble for T = double, and StringToFloat for T = float.
208
  template <typename T>
209
  T StringTo(const char* buffer,
210
             int length,
211
             int* processed_characters_count) const;
212
213
  // Same as StringTo above but for 16 bit characters.
214
  template <typename T>
215
  T StringTo(const uc16* buffer,
216
             int length,
217
             int* processed_characters_count) const;
218
219
 private:
220
  const int flags_;
221
  const double empty_string_value_;
222
  const double junk_string_value_;
223
  const char* const infinity_symbol_;
224
  const char* const nan_symbol_;
225
  const uc16 separator_;
226
227
  template <class Iterator>
228
  double StringToIeee(Iterator start_pointer,
229
                      int length,
230
                      bool read_as_double,
231
                      int* processed_characters_count) const;
232
233
  DOUBLE_CONVERSION_DISALLOW_IMPLICIT_CONSTRUCTORS(StringToDoubleConverter);
234
};
235
236
}  // namespace double_conversion
237
238
#endif  // DOUBLE_CONVERSION_STRING_TO_DOUBLE_H_