52 lines
1.1 KiB
C
52 lines
1.1 KiB
C
|
/* unfortunately, we cannot just do an atof and convert result to float
|
||
|
|
is neccessary, because that might result in over/underflow at an
|
||
|
|
unexpected moment. For the time being, overflow in floating point
|
||
|
|
constants goes undetected
|
||
|
|
*/
|
||
|
|
con_float(argval, str, res)
|
||
|
|
char *str, *res;
|
||
|
|
{
|
||
|
|
double f;
|
||
|
|
double atof();
|
||
|
|
int i;
|
||
|
|
double frexp(), ldexp();
|
||
|
|
int j;
|
||
|
|
float fl;
|
||
|
|
char *p;
|
||
|
|
|
||
|
|
f = atof(str);
|
||
|
|
if (f == 0 || argval == 8) {
|
||
|
|
p = (char *) &f;
|
||
|
|
while (argval--) *res++ = *p++;
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
f = frexp(f, &i);
|
||
|
|
fl = f;
|
||
|
|
fl = frexp(fl,&j);
|
||
|
|
if (i+j > 127) {
|
||
|
|
/* overflow situation. Unfortunately we don't have the
|
||
|
|
slightest idea where the floating point constant came
|
||
|
|
from, so, for the time being, just ignore
|
||
|
|
*/
|
||
|
|
*res++ = f < 0 ? 0377 : 0177;
|
||
|
|
*res++ = 0377;
|
||
|
|
*res++ = 0377;
|
||
|
|
*res = 0377;
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
if (i+j < -127) {
|
||
|
|
/* underflow situation. Unfortunately we don't have the
|
||
|
|
slightest idea where the floating point constant came
|
||
|
|
from, so, for the time being, just ignore
|
||
|
|
*/
|
||
|
|
*res++ = f < 0 ? 0200 : 0;
|
||
|
|
*res++ = 0200;
|
||
|
|
*res++ = 0;
|
||
|
|
*res = 0;
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
fl = ldexp(fl, i+j);
|
||
|
|
p = (char *) &fl;
|
||
|
|
while (argval--) *res++ = *p++;
|
||
|
|
}
|