1 // © 2018 and later: Unicode, Inc. and others. 2 // License & terms of use: http://www.unicode.org/copyright.html 3 // 4 // From the double-conversion library. Original license: 5 // 6 // Copyright 2010 the V8 project authors. All rights reserved. 7 // Redistribution and use in source and binary forms, with or without 8 // modification, are permitted provided that the following conditions are 9 // met: 10 // 11 // * Redistributions of source code must retain the above copyright 12 // notice, this list of conditions and the following disclaimer. 13 // * Redistributions in binary form must reproduce the above 14 // copyright notice, this list of conditions and the following 15 // disclaimer in the documentation and/or other materials provided 16 // with the distribution. 17 // * Neither the name of Google Inc. nor the names of its 18 // contributors may be used to endorse or promote products derived 19 // from this software without specific prior written permission. 20 // 21 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 22 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 23 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 24 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 25 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 26 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 27 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 28 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 29 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 30 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 31 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 32 33 // ICU PATCH: ifdef around UCONFIG_NO_FORMATTING 34 #include "unicode/utypes.h" 35 #if !UCONFIG_NO_FORMATTING 36 37 #ifndef DOUBLE_CONVERSION_FAST_DTOA_H_ 38 #define DOUBLE_CONVERSION_FAST_DTOA_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 45 U_NAMESPACE_BEGIN 46 47 namespace double_conversion { 48 49 enum FastDtoaMode { 50 // Computes the shortest representation of the given input. The returned 51 // result will be the most accurate number of this length. Longer 52 // representations might be more accurate. 53 FAST_DTOA_SHORTEST, 54 // Same as FAST_DTOA_SHORTEST but for single-precision floats. 55 FAST_DTOA_SHORTEST_SINGLE, 56 // Computes a representation where the precision (number of digits) is 57 // given as input. The precision is independent of the decimal point. 58 FAST_DTOA_PRECISION 59 }; 60 61 // FastDtoa will produce at most kFastDtoaMaximalLength digits. This does not 62 // include the terminating '\0' character. 63 static const int kFastDtoaMaximalLength = 17; 64 // Same for single-precision numbers. 65 static const int kFastDtoaMaximalSingleLength = 9; 66 67 // Provides a decimal representation of v. 68 // The result should be interpreted as buffer * 10^(point - length). 69 // 70 // Precondition: 71 // * v must be a strictly positive finite double. 72 // 73 // Returns true if it succeeds, otherwise the result can not be trusted. 74 // There will be *length digits inside the buffer followed by a null terminator. 75 // If the function returns true and mode equals 76 // - FAST_DTOA_SHORTEST, then 77 // the parameter requested_digits is ignored. 78 // The result satisfies 79 // v == (double) (buffer * 10^(point - length)). 80 // The digits in the buffer are the shortest representation possible. E.g. 81 // if 0.099999999999 and 0.1 represent the same double then "1" is returned 82 // with point = 0. 83 // The last digit will be closest to the actual v. That is, even if several 84 // digits might correctly yield 'v' when read again, the buffer will contain 85 // the one closest to v. 86 // - FAST_DTOA_PRECISION, then 87 // the buffer contains requested_digits digits. 88 // the difference v - (buffer * 10^(point-length)) is closest to zero for 89 // all possible representations of requested_digits digits. 90 // If there are two values that are equally close, then FastDtoa returns 91 // false. 92 // For both modes the buffer must be large enough to hold the result. 93 bool FastDtoa(double d, 94 FastDtoaMode mode, 95 int requested_digits, 96 Vector<char> buffer, 97 int* length, 98 int* decimal_point); 99 100 } // namespace double_conversion 101 102 // ICU PATCH: Close ICU namespace 103 U_NAMESPACE_END 104 105 #endif // DOUBLE_CONVERSION_FAST_DTOA_H_ 106 #endif // ICU PATCH: close #if !UCONFIG_NO_FORMATTING 107