// Copyright 2010 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. #ifndef DOUBLE_CONVERSION_BIGNUM_DTOA_H_ #define DOUBLE_CONVERSION_BIGNUM_DTOA_H_ #include "utils.h" namespace double_conversion { enum BignumDtoaMode { // Return the shortest correct representation. // For example the output of 0.299999999999999988897 is (the less accurate but // correct) 0.3. BIGNUM_DTOA_SHORTEST, // Same as BIGNUM_DTOA_SHORTEST but for single-precision floats. BIGNUM_DTOA_SHORTEST_SINGLE, // Return a fixed number of digits after the decimal point. // For instance fixed(0.1, 4) becomes 0.1000 // If the input number is big, the output will be big. BIGNUM_DTOA_FIXED, // Return a fixed number of digits, no matter what the exponent is. BIGNUM_DTOA_PRECISION }; // Converts the given double 'v' to ascii. // The result should be interpreted as buffer * 10^(point-length). // The buffer will be null-terminated. // // The input v must be > 0 and different from NaN, and Infinity. // // The output depends on the given mode: // - SHORTEST: produce the least amount of digits for which the internal // identity requirement is still satisfied. If the digits are printed // (together with the correct exponent) then reading this number will give // 'v' again. The buffer will choose the representation that is closest to // 'v'. If there are two at the same distance, than the number is round up. // In this mode the 'requested_digits' parameter is ignored. // - FIXED: produces digits necessary to print a given number with // 'requested_digits' digits after the decimal point. The produced digits // might be too short in which case the caller has to fill the gaps with '0's. // Example: toFixed(0.001, 5) is allowed to return buffer="1", point=-2. // Halfway cases are rounded up. The call toFixed(0.15, 2) thus returns // buffer="2", point=0. // Note: the length of the returned buffer has no meaning wrt the significance // of its digits. That is, just because it contains '0's does not mean that // any other digit would not satisfy the internal identity requirement. // - PRECISION: produces 'requested_digits' where the first digit is not '0'. // Even though the length of produced digits usually equals // 'requested_digits', the function is allowed to return fewer digits, in // which case the caller has to fill the missing digits with '0's. // Halfway cases are again rounded up. // 'BignumDtoa' expects the given buffer to be big enough to hold all digits // and a terminating null-character. void BignumDtoa(double v, BignumDtoaMode mode, int requested_digits, Vector<char> buffer, int* length, int* point); } // namespace double_conversion #endif // DOUBLE_CONVERSION_BIGNUM_DTOA_H_