101 lines
2.1 KiB
C
101 lines
2.1 KiB
C
|
#include <_ansi.h>
|
||
|
|
#include <limits.h>
|
||
|
|
#include <errno.h>
|
||
|
|
#include <stdlib.h>
|
||
|
|
#include <reent.h>
|
||
|
|
#include "vfieeefp.h"
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Convert a string to a fixed-point (sign + 31-bits) value.
|
||
|
|
*
|
||
|
|
* Ignores `locale' stuff.
|
||
|
|
*/
|
||
|
|
__int32_t
|
||
|
|
_DEFUN (_strtosfix32_r, (rptr, nptr, endptr),
|
||
|
|
struct _reent *rptr _AND
|
||
|
|
_CONST char *nptr _AND
|
||
|
|
char **endptr)
|
||
|
|
{
|
||
|
|
union double_union dbl;
|
||
|
|
int exp, negexp, sign;
|
||
|
|
unsigned long tmp, tmp2;
|
||
|
|
long result = 0;
|
||
|
|
|
||
|
|
dbl.d = _strtod_r (rptr, nptr, endptr);
|
||
|
|
|
||
|
|
/* treat NAN as domain error, +/- infinity as saturation */
|
||
|
|
if (!finite(dbl.d))
|
||
|
|
{
|
||
|
|
if (isnan (dbl.d))
|
||
|
|
{
|
||
|
|
rptr->_errno = EDOM;
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
rptr->_errno = ERANGE;
|
||
|
|
if (word0(dbl) & Sign_bit)
|
||
|
|
return LONG_MIN;
|
||
|
|
return LONG_MAX;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* check for normal saturation */
|
||
|
|
if (dbl.d >= 1.0)
|
||
|
|
{
|
||
|
|
rptr->_errno = ERANGE;
|
||
|
|
return LONG_MAX;
|
||
|
|
}
|
||
|
|
else if (dbl.d < -1.0)
|
||
|
|
{
|
||
|
|
rptr->_errno = ERANGE;
|
||
|
|
return LONG_MIN;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* otherwise we have normal number in range */
|
||
|
|
|
||
|
|
/* strip off sign and exponent */
|
||
|
|
sign = word0(dbl) & Sign_bit;
|
||
|
|
exp = ((word0(dbl) & Exp_mask) >> Exp_shift) - Bias;
|
||
|
|
negexp = -exp;
|
||
|
|
if (negexp > 31)
|
||
|
|
return 0;
|
||
|
|
word0(dbl) &= ~(Exp_mask | Sign_bit);
|
||
|
|
/* add in implicit normalized bit */
|
||
|
|
word0(dbl) |= Exp_msk1;
|
||
|
|
/* shift so result is contained in single word */
|
||
|
|
tmp = word0(dbl) << Ebits;
|
||
|
|
tmp |= ((unsigned long)word1(dbl) >> (32 - Ebits));
|
||
|
|
if (negexp != 0)
|
||
|
|
{
|
||
|
|
/* perform rounding */
|
||
|
|
tmp2 = tmp + (1 << (negexp - 1));
|
||
|
|
result = (long)(tmp2 >> negexp);
|
||
|
|
/* check if rounding caused carry bit which must be added into result */
|
||
|
|
if (tmp2 < tmp)
|
||
|
|
result |= (1 << (32 - negexp));
|
||
|
|
/* check if positive saturation has occurred because of rounding */
|
||
|
|
if (!sign && result < 0)
|
||
|
|
{
|
||
|
|
rptr->_errno = ERANGE;
|
||
|
|
return LONG_MAX;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
/* we have -1.0, no rounding necessary */
|
||
|
|
return LONG_MIN;
|
||
|
|
}
|
||
|
|
|
||
|
|
return sign ? -result : result;
|
||
|
|
}
|
||
|
|
|
||
|
|
#ifndef _REENT_ONLY
|
||
|
|
|
||
|
|
__int32_t
|
||
|
|
_DEFUN (strtosfix32, (s, ptr, base),
|
||
|
|
_CONST char *s _AND
|
||
|
|
char **ptr)
|
||
|
|
{
|
||
|
|
return _strtosfix32_r (_REENT, s, ptr);
|
||
|
|
}
|
||
|
|
|
||
|
|
#endif
|