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https://git.code.sf.net/p/mingw-w64/mingw-w64
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b190082731
As of Jan. 06 2023. Changelog from http://netlib.org/fp/changes (filtered): 20121220 dtoa.c and gdtoa.tgz: to avoid a possible one-time race when Infinity or NaN appear in decimal->binary conversions done in parallel threads, replace hexdig_init() with static initialization. 20131209 dtoa.c, gdtoa.tgz: when strtod computes its starting approximation, allow z to involve one more digit for IEEE arithmetic and two more digits for IBM-mainframe and VAX arithmetics. Thanks to Walter Qian (water.qian@gmail.com) for suggesting this change, which makes some conversions faster. 20151020 dtoa.c: add a test for dtoa() to return "1" under mode 4 when converting some very small powers of 10, such as 1e-322 with ndigits = 4 and 1e-319 with ndigits = 7 (examples provided by jay.foad@gmail.com). 20160219 gdtoa.tgz: Adjust gdtoa(...,mode,...) to assume "round near" when mode is 0 or 1. Make various tweaks to banish (useless) warnings from "gcc -Wall -Wextra". Thanks to Jarkko Hietaniemi <jhi@iki.fi> for advocating the latter exercise (and correcting a typo in README). 20160307 dtoa.c: fix glitches with floating-point values in hexadecimal notation: some values that should overflow to (appropriately signed) Infinity, such as 0x1p1025, were mishandled, and values greater than 0x1p-1075 and less than 0x1.0000000000001p-1075 where treated as zero rather than the smallest denormal number. gdtoa.tgz: fix a bug with hexadecimal input greater than the smallest denormal and less than the smallest denormal times the smallest number greater than one. In round-to-nearest values, such values should round to the smallest denormal rather than to zero. Thanks to Albert Chan <albertmcchan@yahoo.com> for bug reports. 20160325 dtoa.c: fix a bug whereby dtoa(...,mode,...) with, e.g., mode = 2 or 3 could return a string with trailing zeros, contrary to specification. An example provided by Albert Chan: dtoa(81320560005., 2, 10,...). gdtoa.tgz: fix the analogous bug in gdtoa/dtoa.c and gdtoa/gdtoa.c and apply the bug fix of 20151020 to gdtoa/dtoa.c. 20160429 dtoa.c, gdtoa.tgz (file dtoa.c): Fix a bug with dtoa mode 0 when Honor_FLT_ROUNDS is defined: with some inputs and nondefault rounding modes (e.g., 1.23 with round toward zero), the returned string was off by one. When the new 64-bit integer logic is used, the test in question is very unlikely to be used. This is another bug reported by Albert Chan. 20160505 dtoa.c: fix some glitches in strtod() when Honor_FLT_ROUNDS is defined: zero was returned for some decimal values that should have been rounded to +- the smallest denormal, and +-Infinity was returned for some hexadecimal strings with huge values that should have been rounded to +- the largest finite value. 20160506 gdtoa.tgz: analogous bug fixes to those of 20160505. 20180730 strtodg.c in gdtoa.c: fix a glitch, introduced 20160506, with some return values of +-Infinity: the STRTOG_Overflow bit was not set.
91 lines
2.5 KiB
C
91 lines
2.5 KiB
C
/****************************************************************
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The author of this software is David M. Gay.
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Copyright (C) 1998 by Lucent Technologies
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All Rights Reserved
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Permission to use, copy, modify, and distribute this software and
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its documentation for any purpose and without fee is hereby
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granted, provided that the above copyright notice appear in all
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copies and that both that the copyright notice and this
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permission notice and warranty disclaimer appear in supporting
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documentation, and that the name of Lucent or any of its entities
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not be used in advertising or publicity pertaining to
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distribution of the software without specific, written prior
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permission.
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LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
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INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
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IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY
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SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
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WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
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IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
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ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
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THIS SOFTWARE.
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****************************************************************/
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/* Please send bug reports to David M. Gay (dmg at acm dot org,
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* with " at " changed at "@" and " dot " changed to "."). */
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#include "gdtoaimp.h"
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char *__g_dfmt (char *buf, double *d, int ndig, size_t bufsize)
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{
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static FPI fpi0 = { 53, 1-1023-53+1, 2046-1023-53+1, 1, 0, Int_max };
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char *b, *s, *se;
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ULong bits[2], *L, sign;
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int decpt, ex, i, mode;
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#ifdef Honor_FLT_ROUNDS
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#include "gdtoa_fltrnds.h"
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#else
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#define fpi &fpi0
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#endif
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if (ndig < 0)
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ndig = 0;
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if (bufsize < (size_t)(ndig + 10))
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return 0;
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L = (ULong*)d;
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sign = L[_0] & 0x80000000L;
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if ((L[_0] & 0x7ff00000) == 0x7ff00000) {
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/* Infinity or NaN */
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if (bufsize < 10)
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return 0;
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if (L[_0] & 0xfffff || L[_1]) {
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return strcp(buf, "NaN");
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}
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b = buf;
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if (sign)
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*b++ = '-';
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return strcp(b, "Infinity");
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}
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if (L[_1] == 0 && (L[_0] ^ sign) == 0 /*d == 0.*/) {
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b = buf;
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#ifndef IGNORE_ZERO_SIGN
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if (L[_0] & 0x80000000L)
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*b++ = '-';
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#endif
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*b++ = '0';
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*b = 0;
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return b;
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}
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bits[0] = L[_1];
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bits[1] = L[_0] & 0xfffff;
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if ( (ex = (L[_0] >> 20) & 0x7ff) !=0)
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bits[1] |= 0x100000;
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else
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ex = 1;
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ex -= 0x3ff + 52;
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mode = 2;
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if (ndig <= 0)
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mode = 0;
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i = STRTOG_Normal;
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if (sign)
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i = STRTOG_Normal | STRTOG_Neg;
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s = __gdtoa(fpi, ex, bits, &i, mode, ndig, &decpt, &se);
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return __g__fmt(buf, s, se, decpt, sign, bufsize);
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}
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