newlib-cygwin/newlib/libc/stdlib/__adjust.c

44 lines
703 B
C

/*
* return (*acc) scaled by 10**dexp.
*/
#include <_ansi.h>
#include <reent.h>
#include "std.h"
#define abs(x) (((x) < 0) ? -(x) : (x))
double
__adjust (struct _reent *ptr,
double *acc,
int dexp,
int sign)
/* *acc the 64 bit accumulator */
/* dexp decimal exponent */
/* sign sign flag */
{
double r;
if (dexp > MAXE)
{
_REENT_ERRNO(ptr) = ERANGE;
return (sign) ? -HUGE_VAL : HUGE_VAL;
}
else if (dexp < MINE)
{
_REENT_ERRNO(ptr) = ERANGE;
return 0.0;
}
r = *acc;
if (sign)
r = -r;
if (dexp == 0)
return r;
if (dexp < 0)
return r / __exp10 (abs (dexp));
else
return r * __exp10 (dexp);
}