/* * This file is part of the UCB release of Plan 9. It is subject to the license * terms in the LICENSE file found in the top-level directory of this * distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No * part of the UCB release of Plan 9, including this file, may be copied, * modified, propagated, or distributed except according to the terms contained * in the LICENSE file. */#include <math.h>#include <errno.h>/* modf suitable for IEEE double-precision */#define MASK 0x7ffL#define SIGN 0x80000000#define SHIFT 20#define BIAS 1022Ltypedef union{ double d; struct { long ms; long ls; } i;} Cheat;doublemodf(double d, double *ip){ Cheat x; int e; if(-1 < d && d < 1) { *ip = 0; return d; } x.d = d; x.i.ms &= ~SIGN; e = (x.i.ms >> SHIFT) & MASK; if(e == MASK || e == 0){ errno = EDOM; *ip = (d > 0)? HUGE_VAL : -HUGE_VAL; return 0; } e -= BIAS; if(e <= SHIFT+1) { x.i.ms &= ~(0x1fffffL >> e); x.i.ls = 0; } else if(e <= SHIFT+33) x.i.ls &= ~(0x7fffffffL >> (e-SHIFT-2)); if(d > 0){ *ip = x.d; return d - x.d; }else{ *ip = -x.d; return d + x.d; }}
/*
* This file is part of the UCB release of Plan 9. It is subject to the license
* terms in the LICENSE file found in the top-level directory of this
* distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No
* part of the UCB release of Plan 9, including this file, may be copied,
* modified, propagated, or distributed except according to the terms contained
* in the LICENSE file.
*/
#include <math.h>
#include <errno.h>
/* modf suitable for IEEE double-precision */
#define MASK 0x7ffL
#define SIGN 0x80000000
#define SHIFT 20
#define BIAS 1022L
typedef union
{
double d;
struct
{
long ms;
long ls;
} i;
} Cheat;
double
modf(double d, double *ip)
{
Cheat x;
int e;
if(-1 < d && d < 1) {
*ip = 0;
return d;
}
x.d = d;
x.i.ms &= ~SIGN;
e = (x.i.ms >> SHIFT) & MASK;
if(e == MASK || e == 0){
errno = EDOM;
*ip = (d > 0)? HUGE_VAL : -HUGE_VAL;
return 0;
}
e -= BIAS;
if(e <= SHIFT+1) {
x.i.ms &= ~(0x1fffffL >> e);
x.i.ls = 0;
} else
if(e <= SHIFT+33)
x.i.ls &= ~(0x7fffffffL >> (e-SHIFT-2));
if(d > 0){
*ip = x.d;
return d - x.d;
}else{
*ip = -x.d;
return d + x.d;
}
}