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3//
4// From the double-conversion library. Original license:
5//
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32
33// ICU PATCH: ifdef around UCONFIG_NO_FORMATTING
34#include "unicode/utypes.h"
35#if !UCONFIG_NO_FORMATTING
36
37#ifndef DOUBLE_CONVERSION_STRING_TO_DOUBLE_H_
38#define DOUBLE_CONVERSION_STRING_TO_DOUBLE_H_
39
40// ICU PATCH: Customize header file paths for ICU.
41
42#include "double-conversion-utils.h"
43
44// ICU PATCH: Wrap in ICU namespace
45U_NAMESPACE_BEGIN
46
47namespace double_conversion {
48
49class StringToDoubleConverter {
50 public:
51 // Enumeration for allowing octals and ignoring junk when converting
52 // strings to numbers.
53 enum Flags {
54 NO_FLAGS = 0,
55 ALLOW_HEX = 1,
56 ALLOW_OCTALS = 2,
57 ALLOW_TRAILING_JUNK = 4,
58 ALLOW_LEADING_SPACES = 8,
59 ALLOW_TRAILING_SPACES = 16,
60 ALLOW_SPACES_AFTER_SIGN = 32,
61 ALLOW_CASE_INSENSITIVITY = 64,
62 ALLOW_CASE_INSENSIBILITY = 64, // Deprecated
63 ALLOW_HEX_FLOATS = 128,
64 };
65
66 static const uc16 kNoSeparator = '\0';
67
68 // Flags should be a bit-or combination of the possible Flags-enum.
69 // - NO_FLAGS: no special flags.
70 // - ALLOW_HEX: recognizes the prefix "0x". Hex numbers may only be integers.
71 // Ex: StringToDouble("0x1234") -> 4660.0
72 // In StringToDouble("0x1234.56") the characters ".56" are trailing
73 // junk. The result of the call is hence dependent on
74 // the ALLOW_TRAILING_JUNK flag and/or the junk value.
75 // With this flag "0x" is a junk-string. Even with ALLOW_TRAILING_JUNK,
76 // the string will not be parsed as "0" followed by junk.
77 //
78 // - ALLOW_OCTALS: recognizes the prefix "0" for octals:
79 // If a sequence of octal digits starts with '0', then the number is
80 // read as octal integer. Octal numbers may only be integers.
81 // Ex: StringToDouble("01234") -> 668.0
82 // StringToDouble("012349") -> 12349.0 // Not a sequence of octal
83 // // digits.
84 // In StringToDouble("01234.56") the characters ".56" are trailing
85 // junk. The result of the call is hence dependent on
86 // the ALLOW_TRAILING_JUNK flag and/or the junk value.
87 // In StringToDouble("01234e56") the characters "e56" are trailing
88 // junk, too.
89 // - ALLOW_TRAILING_JUNK: ignore trailing characters that are not part of
90 // a double literal.
91 // - ALLOW_LEADING_SPACES: skip over leading whitespace, including spaces,
92 // new-lines, and tabs.
93 // - ALLOW_TRAILING_SPACES: ignore trailing whitespace.
94 // - ALLOW_SPACES_AFTER_SIGN: ignore whitespace after the sign.
95 // Ex: StringToDouble("- 123.2") -> -123.2.
96 // StringToDouble("+ 123.2") -> 123.2
97 // - ALLOW_CASE_INSENSITIVITY: ignore case of characters for special values:
98 // infinity and nan.
99 // - ALLOW_HEX_FLOATS: allows hexadecimal float literals.
100 // This *must* start with "0x" and separate the exponent with "p".
101 // Examples: 0x1.2p3 == 9.0
102 // 0x10.1p0 == 16.0625
103 // ALLOW_HEX and ALLOW_HEX_FLOATS are indendent.
104 //
105 // empty_string_value is returned when an empty string is given as input.
106 // If ALLOW_LEADING_SPACES or ALLOW_TRAILING_SPACES are set, then a string
107 // containing only spaces is converted to the 'empty_string_value', too.
108 //
109 // junk_string_value is returned when
110 // a) ALLOW_TRAILING_JUNK is not set, and a junk character (a character not
111 // part of a double-literal) is found.
112 // b) ALLOW_TRAILING_JUNK is set, but the string does not start with a
113 // double literal.
114 //
115 // infinity_symbol and nan_symbol are strings that are used to detect
116 // inputs that represent infinity and NaN. They can be null, in which case
117 // they are ignored.
118 // The conversion routine first reads any possible signs. Then it compares the
119 // following character of the input-string with the first character of
120 // the infinity, and nan-symbol. If either matches, the function assumes, that
121 // a match has been found, and expects the following input characters to match
122 // the remaining characters of the special-value symbol.
123 // This means that the following restrictions apply to special-value symbols:
124 // - they must not start with signs ('+', or '-'),
125 // - they must not have the same first character.
126 // - they must not start with digits.
127 //
128 // If the separator character is not kNoSeparator, then that specific
129 // character is ignored when in between two valid digits of the significant.
130 // It is not allowed to appear in the exponent.
131 // It is not allowed to lead or trail the number.
132 // It is not allowed to appear twice next to each other.
133 //
134 // Examples:
135 // flags = ALLOW_HEX | ALLOW_TRAILING_JUNK,
136 // empty_string_value = 0.0,
137 // junk_string_value = NaN,
138 // infinity_symbol = "infinity",
139 // nan_symbol = "nan":
140 // StringToDouble("0x1234") -> 4660.0.
141 // StringToDouble("0x1234K") -> 4660.0.
142 // StringToDouble("") -> 0.0 // empty_string_value.
143 // StringToDouble(" ") -> NaN // junk_string_value.
144 // StringToDouble(" 1") -> NaN // junk_string_value.
145 // StringToDouble("0x") -> NaN // junk_string_value.
146 // StringToDouble("-123.45") -> -123.45.
147 // StringToDouble("--123.45") -> NaN // junk_string_value.
148 // StringToDouble("123e45") -> 123e45.
149 // StringToDouble("123E45") -> 123e45.
150 // StringToDouble("123e+45") -> 123e45.
151 // StringToDouble("123E-45") -> 123e-45.
152 // StringToDouble("123e") -> 123.0 // trailing junk ignored.
153 // StringToDouble("123e-") -> 123.0 // trailing junk ignored.
154 // StringToDouble("+NaN") -> NaN // NaN string literal.
155 // StringToDouble("-infinity") -> -inf. // infinity literal.
156 // StringToDouble("Infinity") -> NaN // junk_string_value.
157 //
158 // flags = ALLOW_OCTAL | ALLOW_LEADING_SPACES,
159 // empty_string_value = 0.0,
160 // junk_string_value = NaN,
161 // infinity_symbol = NULL,
162 // nan_symbol = NULL:
163 // StringToDouble("0x1234") -> NaN // junk_string_value.
164 // StringToDouble("01234") -> 668.0.
165 // StringToDouble("") -> 0.0 // empty_string_value.
166 // StringToDouble(" ") -> 0.0 // empty_string_value.
167 // StringToDouble(" 1") -> 1.0
168 // StringToDouble("0x") -> NaN // junk_string_value.
169 // StringToDouble("0123e45") -> NaN // junk_string_value.
170 // StringToDouble("01239E45") -> 1239e45.
171 // StringToDouble("-infinity") -> NaN // junk_string_value.
172 // StringToDouble("NaN") -> NaN // junk_string_value.
173 //
174 // flags = NO_FLAGS,
175 // separator = ' ':
176 // StringToDouble("1 2 3 4") -> 1234.0
177 // StringToDouble("1 2") -> NaN // junk_string_value
178 // StringToDouble("1 000 000.0") -> 1000000.0
179 // StringToDouble("1.000 000") -> 1.0
180 // StringToDouble("1.0e1 000") -> NaN // junk_string_value
181 StringToDoubleConverter(int flags,
182 double empty_string_value,
183 double junk_string_value,
184 const char* infinity_symbol,
185 const char* nan_symbol,
186 uc16 separator = kNoSeparator)
187 : flags_(flags),
188 empty_string_value_(empty_string_value),
189 junk_string_value_(junk_string_value),
190 infinity_symbol_(infinity_symbol),
191 nan_symbol_(nan_symbol),
192 separator_(separator) {
193 }
194
195 // Performs the conversion.
196 // The output parameter 'processed_characters_count' is set to the number
197 // of characters that have been processed to read the number.
198 // Spaces than are processed with ALLOW_{LEADING|TRAILING}_SPACES are included
199 // in the 'processed_characters_count'. Trailing junk is never included.
200 double StringToDouble(const char* buffer,
201 int length,
202 int* processed_characters_count) const;
203
204 // Same as StringToDouble above but for 16 bit characters.
205 double StringToDouble(const uc16* buffer,
206 int length,
207 int* processed_characters_count) const;
208
209 // Same as StringToDouble but reads a float.
210 // Note that this is not equivalent to static_cast<float>(StringToDouble(...))
211 // due to potential double-rounding.
212 float StringToFloat(const char* buffer,
213 int length,
214 int* processed_characters_count) const;
215
216 // Same as StringToFloat above but for 16 bit characters.
217 float StringToFloat(const uc16* buffer,
218 int length,
219 int* processed_characters_count) const;
220
221 private:
222 const int flags_;
223 const double empty_string_value_;
224 const double junk_string_value_;
225 const char* const infinity_symbol_;
226 const char* const nan_symbol_;
227 const uc16 separator_;
228
229 template <class Iterator>
230 double StringToIeee(Iterator start_pointer,
231 int length,
232 bool read_as_double,
233 int* processed_characters_count) const;
234
235 DOUBLE_CONVERSION_DISALLOW_IMPLICIT_CONSTRUCTORS(StringToDoubleConverter);
236};
237
238} // namespace double_conversion
239
240// ICU PATCH: Close ICU namespace
241U_NAMESPACE_END
242
243#endif // DOUBLE_CONVERSION_STRING_TO_DOUBLE_H_
244#endif // ICU PATCH: close #if !UCONFIG_NO_FORMATTING
245