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Diffstat (limited to 'intl/icu/source/i18n/double-conversion-string-to-double.h')
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1 files changed, 256 insertions, 0 deletions
diff --git a/intl/icu/source/i18n/double-conversion-string-to-double.h b/intl/icu/source/i18n/double-conversion-string-to-double.h new file mode 100644 index 0000000000..1d4e3dddde --- /dev/null +++ b/intl/icu/source/i18n/double-conversion-string-to-double.h @@ -0,0 +1,256 @@ +// © 2018 and later: Unicode, Inc. and others. +// License & terms of use: http://www.unicode.org/copyright.html +// +// From the double-conversion library. Original license: +// +// Copyright 2012 the V8 project authors. All rights reserved. +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following +// disclaimer in the documentation and/or other materials provided +// with the distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived +// from this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +// ICU PATCH: ifdef around UCONFIG_NO_FORMATTING +#include "unicode/utypes.h" +#if !UCONFIG_NO_FORMATTING + +#ifndef DOUBLE_CONVERSION_STRING_TO_DOUBLE_H_ +#define DOUBLE_CONVERSION_STRING_TO_DOUBLE_H_ + +// ICU PATCH: Customize header file paths for ICU. + +#include "double-conversion-utils.h" + +// ICU PATCH: Wrap in ICU namespace +U_NAMESPACE_BEGIN + +namespace double_conversion { + +class StringToDoubleConverter { + public: + // Enumeration for allowing octals and ignoring junk when converting + // strings to numbers. + enum Flags { + NO_FLAGS = 0, + ALLOW_HEX = 1, + ALLOW_OCTALS = 2, + ALLOW_TRAILING_JUNK = 4, + ALLOW_LEADING_SPACES = 8, + ALLOW_TRAILING_SPACES = 16, + ALLOW_SPACES_AFTER_SIGN = 32, + ALLOW_CASE_INSENSITIVITY = 64, + ALLOW_CASE_INSENSIBILITY = 64, // Deprecated + ALLOW_HEX_FLOATS = 128, + }; + + static const uc16 kNoSeparator = '\0'; + + // Flags should be a bit-or combination of the possible Flags-enum. + // - NO_FLAGS: no special flags. + // - ALLOW_HEX: recognizes the prefix "0x". Hex numbers may only be integers. + // Ex: StringToDouble("0x1234") -> 4660.0 + // In StringToDouble("0x1234.56") the characters ".56" are trailing + // junk. The result of the call is hence dependent on + // the ALLOW_TRAILING_JUNK flag and/or the junk value. + // With this flag "0x" is a junk-string. Even with ALLOW_TRAILING_JUNK, + // the string will not be parsed as "0" followed by junk. + // + // - ALLOW_OCTALS: recognizes the prefix "0" for octals: + // If a sequence of octal digits starts with '0', then the number is + // read as octal integer. Octal numbers may only be integers. + // Ex: StringToDouble("01234") -> 668.0 + // StringToDouble("012349") -> 12349.0 // Not a sequence of octal + // // digits. + // In StringToDouble("01234.56") the characters ".56" are trailing + // junk. The result of the call is hence dependent on + // the ALLOW_TRAILING_JUNK flag and/or the junk value. + // In StringToDouble("01234e56") the characters "e56" are trailing + // junk, too. + // - ALLOW_TRAILING_JUNK: ignore trailing characters that are not part of + // a double literal. + // - ALLOW_LEADING_SPACES: skip over leading whitespace, including spaces, + // new-lines, and tabs. + // - ALLOW_TRAILING_SPACES: ignore trailing whitespace. + // - ALLOW_SPACES_AFTER_SIGN: ignore whitespace after the sign. + // Ex: StringToDouble("- 123.2") -> -123.2. + // StringToDouble("+ 123.2") -> 123.2 + // - ALLOW_CASE_INSENSITIVITY: ignore case of characters for special values: + // infinity and nan. + // - ALLOW_HEX_FLOATS: allows hexadecimal float literals. + // This *must* start with "0x" and separate the exponent with "p". + // Examples: 0x1.2p3 == 9.0 + // 0x10.1p0 == 16.0625 + // ALLOW_HEX and ALLOW_HEX_FLOATS are indented. + // + // empty_string_value is returned when an empty string is given as input. + // If ALLOW_LEADING_SPACES or ALLOW_TRAILING_SPACES are set, then a string + // containing only spaces is converted to the 'empty_string_value', too. + // + // junk_string_value is returned when + // a) ALLOW_TRAILING_JUNK is not set, and a junk character (a character not + // part of a double-literal) is found. + // b) ALLOW_TRAILING_JUNK is set, but the string does not start with a + // double literal. + // + // infinity_symbol and nan_symbol are strings that are used to detect + // inputs that represent infinity and NaN. They can be null, in which case + // they are ignored. + // The conversion routine first reads any possible signs. Then it compares the + // following character of the input-string with the first character of + // the infinity, and nan-symbol. If either matches, the function assumes, that + // a match has been found, and expects the following input characters to match + // the remaining characters of the special-value symbol. + // This means that the following restrictions apply to special-value symbols: + // - they must not start with signs ('+', or '-'), + // - they must not have the same first character. + // - they must not start with digits. + // + // If the separator character is not kNoSeparator, then that specific + // character is ignored when in between two valid digits of the significant. + // It is not allowed to appear in the exponent. + // It is not allowed to lead or trail the number. + // It is not allowed to appear twice next to each other. + // + // Examples: + // flags = ALLOW_HEX | ALLOW_TRAILING_JUNK, + // empty_string_value = 0.0, + // junk_string_value = NaN, + // infinity_symbol = "infinity", + // nan_symbol = "nan": + // StringToDouble("0x1234") -> 4660.0. + // StringToDouble("0x1234K") -> 4660.0. + // StringToDouble("") -> 0.0 // empty_string_value. + // StringToDouble(" ") -> NaN // junk_string_value. + // StringToDouble(" 1") -> NaN // junk_string_value. + // StringToDouble("0x") -> NaN // junk_string_value. + // StringToDouble("-123.45") -> -123.45. + // StringToDouble("--123.45") -> NaN // junk_string_value. + // StringToDouble("123e45") -> 123e45. + // StringToDouble("123E45") -> 123e45. + // StringToDouble("123e+45") -> 123e45. + // StringToDouble("123E-45") -> 123e-45. + // StringToDouble("123e") -> 123.0 // trailing junk ignored. + // StringToDouble("123e-") -> 123.0 // trailing junk ignored. + // StringToDouble("+NaN") -> NaN // NaN string literal. + // StringToDouble("-infinity") -> -inf. // infinity literal. + // StringToDouble("Infinity") -> NaN // junk_string_value. + // + // flags = ALLOW_OCTAL | ALLOW_LEADING_SPACES, + // empty_string_value = 0.0, + // junk_string_value = NaN, + // infinity_symbol = nullptr, + // nan_symbol = nullptr: + // StringToDouble("0x1234") -> NaN // junk_string_value. + // StringToDouble("01234") -> 668.0. + // StringToDouble("") -> 0.0 // empty_string_value. + // StringToDouble(" ") -> 0.0 // empty_string_value. + // StringToDouble(" 1") -> 1.0 + // StringToDouble("0x") -> NaN // junk_string_value. + // StringToDouble("0123e45") -> NaN // junk_string_value. + // StringToDouble("01239E45") -> 1239e45. + // StringToDouble("-infinity") -> NaN // junk_string_value. + // StringToDouble("NaN") -> NaN // junk_string_value. + // + // flags = NO_FLAGS, + // separator = ' ': + // StringToDouble("1 2 3 4") -> 1234.0 + // StringToDouble("1 2") -> NaN // junk_string_value + // StringToDouble("1 000 000.0") -> 1000000.0 + // StringToDouble("1.000 000") -> 1.0 + // StringToDouble("1.0e1 000") -> NaN // junk_string_value + StringToDoubleConverter(int flags, + double empty_string_value, + double junk_string_value, + const char* infinity_symbol, + const char* nan_symbol, + uc16 separator = kNoSeparator) + : flags_(flags), + empty_string_value_(empty_string_value), + junk_string_value_(junk_string_value), + infinity_symbol_(infinity_symbol), + nan_symbol_(nan_symbol), + separator_(separator) { + } + + // Performs the conversion. + // The output parameter 'processed_characters_count' is set to the number + // of characters that have been processed to read the number. + // Spaces than are processed with ALLOW_{LEADING|TRAILING}_SPACES are included + // in the 'processed_characters_count'. Trailing junk is never included. + double StringToDouble(const char* buffer, + int length, + int* processed_characters_count) const; + + // Same as StringToDouble above but for 16 bit characters. + double StringToDouble(const uc16* buffer, + int length, + int* processed_characters_count) const; + + // Same as StringToDouble but reads a float. + // Note that this is not equivalent to static_cast<float>(StringToDouble(...)) + // due to potential double-rounding. + float StringToFloat(const char* buffer, + int length, + int* processed_characters_count) const; + + // Same as StringToFloat above but for 16 bit characters. + float StringToFloat(const uc16* buffer, + int length, + int* processed_characters_count) const; + + // Same as StringToDouble for T = double, and StringToFloat for T = float. + template <typename T> + T StringTo(const char* buffer, + int length, + int* processed_characters_count) const; + + // Same as StringTo above but for 16 bit characters. + template <typename T> + T StringTo(const uc16* buffer, + int length, + int* processed_characters_count) const; + + private: + const int flags_; + const double empty_string_value_; + const double junk_string_value_; + const char* const infinity_symbol_; + const char* const nan_symbol_; + const uc16 separator_; + + template <class Iterator> + double StringToIeee(Iterator start_pointer, + int length, + bool read_as_double, + int* processed_characters_count) const; + + DOUBLE_CONVERSION_DISALLOW_IMPLICIT_CONSTRUCTORS(StringToDoubleConverter); +}; + +} // namespace double_conversion + +// ICU PATCH: Close ICU namespace +U_NAMESPACE_END + +#endif // DOUBLE_CONVERSION_STRING_TO_DOUBLE_H_ +#endif // ICU PATCH: close #if !UCONFIG_NO_FORMATTING |