source: trunk/libs/newlib/src/newlib/libc/stdlib/__adjust.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)
    {
      ptr->_errno = ERANGE;
      return (sign) ? -HUGE_VAL : HUGE_VAL;
    }
  else if (dexp < MINE)
    {
      ptr->_errno = 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);
}