lib/gnu/ieee_float/isnan.c

   1 /*
   2 libc/ieee_float/isnan.c
   3
   4 Created:        Oct 14, 1993 by Philip Homburg <philip@cs.vu.nl>
   5
   6 Implementation of isnan that directly tests the bits in an ieee float
   7 */
   8
   9 #define _MINIX_SOURCE
  10
  11 #include <sys/types.h>
  12 #include <math.h>
  13
  14 #include "ieee_float.h"
  15
  16 int isnan(value)
  17 double value;
  18 {
  19         struct f64 *f64p;
  20         int exp;
  21
  22         f64p= (struct f64 *)&value;
  23         exp= F64_GET_EXP(f64p);
  24         if (exp != F64_EXP_MAX)
  25                 return 0;
  26         return F64_GET_MANT_LOW(f64p) != 0 || F64_GET_MANT_HIGH(f64p) != 0;
  27 }
  28
  29 /*
  30  * $PchId: isnan.c,v 1.3 1996/02/22 21:01:39 philip Exp $
  31  */