90 lines
2.4 KiB
C
90 lines
2.4 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*
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#ifdef KR_headers
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g_dfmt(buf, d, ndig, bufsize) char *buf; double *d; int ndig; unsigned bufsize;
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#else
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g_dfmt(char *buf, double *d, int ndig, unsigned bufsize)
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#endif
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{
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static FPI fpi = { 53, 1-1023-53+1, 2046-1023-53+1, 1, 0 };
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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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if (ndig < 0)
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ndig = 0;
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if (bufsize < 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 (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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if (bufsize < 25)
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return 0;
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mode = 0;
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}
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i = STRTOG_Normal;
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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);
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}
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