mirror of
https://github.com/ZDoom/gzdoom.git
synced 2024-11-27 06:12:19 +00:00
171 lines
4.1 KiB
C
171 lines
4.1 KiB
C
/****************************************************************
|
|
|
|
The author of this software is David M. Gay.
|
|
|
|
Copyright (C) 1998 by Lucent Technologies
|
|
All Rights Reserved
|
|
|
|
Permission to use, copy, modify, and distribute this software and
|
|
its documentation for any purpose and without fee is hereby
|
|
granted, provided that the above copyright notice appear in all
|
|
copies and that both that the copyright notice and this
|
|
permission notice and warranty disclaimer appear in supporting
|
|
documentation, and that the name of Lucent or any of its entities
|
|
not be used in advertising or publicity pertaining to
|
|
distribution of the software without specific, written prior
|
|
permission.
|
|
|
|
LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
|
|
INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
|
|
IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY
|
|
SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
|
|
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
|
|
IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
|
|
ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
|
|
THIS SOFTWARE.
|
|
|
|
****************************************************************/
|
|
|
|
/* Please send bug reports to David M. Gay (dmg@acm.org). */
|
|
|
|
#include "gdtoaimp.h"
|
|
#include <string.h>
|
|
|
|
char *
|
|
#ifdef KR_headers
|
|
g_ddfmt(buf, dd0, ndig, bufsize) char *buf; double *dd0; int ndig; size_t bufsize;
|
|
#else
|
|
g_ddfmt(char *buf, double *dd0, int ndig, size_t bufsize)
|
|
#endif
|
|
{
|
|
FPI fpi;
|
|
char *b, *s, *se;
|
|
ULong *L, bits0[4], *bits, *zx;
|
|
int bx, by, decpt, ex, ey, i, j, mode;
|
|
Bigint *x, *y, *z;
|
|
U *dd, ddx[2];
|
|
#ifdef Honor_FLT_ROUNDS /*{{*/
|
|
int Rounding;
|
|
#ifdef Trust_FLT_ROUNDS /*{{ only define this if FLT_ROUNDS really works! */
|
|
Rounding = Flt_Rounds;
|
|
#else /*}{*/
|
|
Rounding = 1;
|
|
switch(fegetround()) {
|
|
case FE_TOWARDZERO: Rounding = 0; break;
|
|
case FE_UPWARD: Rounding = 2; break;
|
|
case FE_DOWNWARD: Rounding = 3;
|
|
}
|
|
#endif /*}}*/
|
|
#else /*}{*/
|
|
#define Rounding FPI_Round_near
|
|
#endif /*}}*/
|
|
|
|
if (bufsize < 10 || bufsize < (size_t)(ndig + 8))
|
|
return 0;
|
|
|
|
dd = (U*)dd0;
|
|
L = dd->L;
|
|
if ((L[_0] & 0x7ff00000L) == 0x7ff00000L) {
|
|
/* Infinity or NaN */
|
|
if (L[_0] & 0xfffff || L[_1]) {
|
|
nanret:
|
|
return strcp(buf, "NaN");
|
|
}
|
|
if ((L[2+_0] & 0x7ff00000) == 0x7ff00000) {
|
|
if (L[2+_0] & 0xfffff || L[2+_1])
|
|
goto nanret;
|
|
if ((L[_0] ^ L[2+_0]) & 0x80000000L)
|
|
goto nanret; /* Infinity - Infinity */
|
|
}
|
|
infret:
|
|
b = buf;
|
|
if (L[_0] & 0x80000000L)
|
|
*b++ = '-';
|
|
return strcp(b, "Infinity");
|
|
}
|
|
if ((L[2+_0] & 0x7ff00000) == 0x7ff00000) {
|
|
L += 2;
|
|
if (L[_0] & 0xfffff || L[_1])
|
|
goto nanret;
|
|
goto infret;
|
|
}
|
|
if (dval(&dd[0]) + dval(&dd[1]) == 0.) {
|
|
b = buf;
|
|
#ifndef IGNORE_ZERO_SIGN
|
|
if (L[_0] & L[2+_0] & 0x80000000L)
|
|
*b++ = '-';
|
|
#endif
|
|
*b++ = '0';
|
|
*b = 0;
|
|
return b;
|
|
}
|
|
if ((L[_0] & 0x7ff00000L) < (L[2+_0] & 0x7ff00000L)) {
|
|
dval(&ddx[1]) = dval(&dd[0]);
|
|
dval(&ddx[0]) = dval(&dd[1]);
|
|
dd = ddx;
|
|
L = dd->L;
|
|
}
|
|
z = d2b(dval(&dd[0]), &ex, &bx);
|
|
if (dval(&dd[1]) == 0.)
|
|
goto no_y;
|
|
x = z;
|
|
y = d2b(dval(&dd[1]), &ey, &by);
|
|
if ( (i = ex - ey) !=0) {
|
|
if (i > 0) {
|
|
x = lshift(x, i);
|
|
ex = ey;
|
|
}
|
|
else
|
|
y = lshift(y, -i);
|
|
}
|
|
if ((L[_0] ^ L[2+_0]) & 0x80000000L) {
|
|
z = diff(x, y);
|
|
if (L[_0] & 0x80000000L)
|
|
z->sign = 1 - z->sign;
|
|
}
|
|
else {
|
|
z = sum(x, y);
|
|
if (L[_0] & 0x80000000L)
|
|
z->sign = 1;
|
|
}
|
|
Bfree(x);
|
|
Bfree(y);
|
|
no_y:
|
|
bits = zx = z->x;
|
|
for(i = 0; !*zx; zx++)
|
|
i += 32;
|
|
i += lo0bits(zx);
|
|
if (i) {
|
|
rshift(z, i);
|
|
ex += i;
|
|
}
|
|
fpi.nbits = z->wds * 32 - hi0bits(z->x[j = z->wds-1]);
|
|
if (fpi.nbits < 106) {
|
|
fpi.nbits = 106;
|
|
if (j < 3) {
|
|
for(i = 0; i <= j; i++)
|
|
bits0[i] = bits[i];
|
|
while(i < 4)
|
|
bits0[i++] = 0;
|
|
bits = bits0;
|
|
}
|
|
}
|
|
mode = 2;
|
|
if (ndig <= 0) {
|
|
if (bufsize < (size_t)((int)(fpi.nbits * .301029995664) + 10)) {
|
|
Bfree(z);
|
|
return 0;
|
|
}
|
|
mode = 0;
|
|
}
|
|
fpi.emin = 1-1023-53+1;
|
|
fpi.emax = 2046-1023-106+1;
|
|
fpi.rounding = Rounding;
|
|
fpi.sudden_underflow = 0;
|
|
fpi.int_max = Int_max;
|
|
i = STRTOG_Normal;
|
|
s = gdtoa(&fpi, ex, bits, &i, mode, ndig, &decpt, &se);
|
|
b = g__fmt(buf, s, se, decpt, z->sign, bufsize);
|
|
Bfree(z);
|
|
return b;
|
|
}
|