1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/mfbt/double-conversion/bignum-dtoa.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,84 @@
1.4 +// Copyright 2010 the V8 project authors. All rights reserved.
1.5 +// Redistribution and use in source and binary forms, with or without
1.6 +// modification, are permitted provided that the following conditions are
1.7 +// met:
1.8 +//
1.9 +// * Redistributions of source code must retain the above copyright
1.10 +// notice, this list of conditions and the following disclaimer.
1.11 +// * Redistributions in binary form must reproduce the above
1.12 +// copyright notice, this list of conditions and the following
1.13 +// disclaimer in the documentation and/or other materials provided
1.14 +// with the distribution.
1.15 +// * Neither the name of Google Inc. nor the names of its
1.16 +// contributors may be used to endorse or promote products derived
1.17 +// from this software without specific prior written permission.
1.18 +//
1.19 +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
1.20 +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
1.21 +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
1.22 +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
1.23 +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
1.24 +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
1.25 +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
1.26 +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
1.27 +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
1.28 +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
1.29 +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.30 +
1.31 +#ifndef DOUBLE_CONVERSION_BIGNUM_DTOA_H_
1.32 +#define DOUBLE_CONVERSION_BIGNUM_DTOA_H_
1.33 +
1.34 +#include "utils.h"
1.35 +
1.36 +namespace double_conversion {
1.37 +
1.38 +enum BignumDtoaMode {
1.39 + // Return the shortest correct representation.
1.40 + // For example the output of 0.299999999999999988897 is (the less accurate but
1.41 + // correct) 0.3.
1.42 + BIGNUM_DTOA_SHORTEST,
1.43 + // Same as BIGNUM_DTOA_SHORTEST but for single-precision floats.
1.44 + BIGNUM_DTOA_SHORTEST_SINGLE,
1.45 + // Return a fixed number of digits after the decimal point.
1.46 + // For instance fixed(0.1, 4) becomes 0.1000
1.47 + // If the input number is big, the output will be big.
1.48 + BIGNUM_DTOA_FIXED,
1.49 + // Return a fixed number of digits, no matter what the exponent is.
1.50 + BIGNUM_DTOA_PRECISION
1.51 +};
1.52 +
1.53 +// Converts the given double 'v' to ascii.
1.54 +// The result should be interpreted as buffer * 10^(point-length).
1.55 +// The buffer will be null-terminated.
1.56 +//
1.57 +// The input v must be > 0 and different from NaN, and Infinity.
1.58 +//
1.59 +// The output depends on the given mode:
1.60 +// - SHORTEST: produce the least amount of digits for which the internal
1.61 +// identity requirement is still satisfied. If the digits are printed
1.62 +// (together with the correct exponent) then reading this number will give
1.63 +// 'v' again. The buffer will choose the representation that is closest to
1.64 +// 'v'. If there are two at the same distance, than the number is round up.
1.65 +// In this mode the 'requested_digits' parameter is ignored.
1.66 +// - FIXED: produces digits necessary to print a given number with
1.67 +// 'requested_digits' digits after the decimal point. The produced digits
1.68 +// might be too short in which case the caller has to fill the gaps with '0's.
1.69 +// Example: toFixed(0.001, 5) is allowed to return buffer="1", point=-2.
1.70 +// Halfway cases are rounded up. The call toFixed(0.15, 2) thus returns
1.71 +// buffer="2", point=0.
1.72 +// Note: the length of the returned buffer has no meaning wrt the significance
1.73 +// of its digits. That is, just because it contains '0's does not mean that
1.74 +// any other digit would not satisfy the internal identity requirement.
1.75 +// - PRECISION: produces 'requested_digits' where the first digit is not '0'.
1.76 +// Even though the length of produced digits usually equals
1.77 +// 'requested_digits', the function is allowed to return fewer digits, in
1.78 +// which case the caller has to fill the missing digits with '0's.
1.79 +// Halfway cases are again rounded up.
1.80 +// 'BignumDtoa' expects the given buffer to be big enough to hold all digits
1.81 +// and a terminating null-character.
1.82 +void BignumDtoa(double v, BignumDtoaMode mode, int requested_digits,
1.83 + Vector<char> buffer, int* length, int* point);
1.84 +
1.85 +} // namespace double_conversion
1.86 +
1.87 +#endif // DOUBLE_CONVERSION_BIGNUM_DTOA_H_
