Home | History | Annotate | Line # | Download | only in gdtoa 
      1 /* $NetBSD: g_Qfmt.c,v 1.5 2019/08/01 02:27:43 riastradh Exp $ */
      2 
      3 /****************************************************************
      4 
      5 The author of this software is David M. Gay.
      6 
      7 Copyright (C) 1998, 2000 by Lucent Technologies
      8 All Rights Reserved
      9 
     10 Permission to use, copy, modify, and distribute this software and
     11 its documentation for any purpose and without fee is hereby
     12 granted, provided that the above copyright notice appear in all
     13 copies and that both that the copyright notice and this
     14 permission notice and warranty disclaimer appear in supporting
     15 documentation, and that the name of Lucent or any of its entities
     16 not be used in advertising or publicity pertaining to
     17 distribution of the software without specific, written prior
     18 permission.
     19 
     20 LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
     21 INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
     22 IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY
     23 SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
     24 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
     25 IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
     26 ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
     27 THIS SOFTWARE.
     28 
     29 ****************************************************************/
     30 
     31 /* Please send bug reports to David M. Gay (dmg at acm dot org,
     32  * with " at " changed at "@" and " dot " changed to ".").	*/
     33 
     34 #include "gdtoaimp.h"
     35 
     36 #undef _0
     37 #undef _1
     38 
     39 /* one or the other of IEEE_BIG_ENDIAN or IEEE_LITTLE_ENDIAN should be #defined */
     40 
     41 #ifdef IEEE_BIG_ENDIAN
     42 #define _0 0
     43 #define _1 1
     44 #define _2 2
     45 #define _3 3
     46 #endif
     47 #ifdef IEEE_LITTLE_ENDIAN
     48 #define _0 3
     49 #define _1 2
     50 #define _2 1
     51 #define _3 0
     52 #endif
     53 
     54  char*
     55 #ifdef KR_headers
     56 g_Qfmt(buf, V, ndig, bufsize) char *buf; char *V; int ndig; size_t bufsize;
     57 #else
     58 g_Qfmt(char *buf, void *V, int ndig, size_t bufsize)
     59 #endif
     60 {
     61 	static CONST FPI fpi0 = { 113, 1-16383-113+1, 32766 - 16383 - 113 + 1, 1, 0 };
     62 	char *b, *s, *se;
     63 	ULong bits[4], *L, sign;
     64 	int decpt, ex, i, mode;
     65 #ifdef Honor_FLT_ROUNDS
     66 #include "gdtoa_fltrnds.h"
     67 #else
     68 #define fpi &fpi0
     69 #endif
     70 
     71 	if (ndig < 0)
     72 		ndig = 0;
     73 	if (bufsize < ndig + 10)
     74 		return 0;
     75 
     76 	L = (ULong*)V;
     77 	sign = L[_0] & 0x80000000L;
     78 	bits[3] = L[_0] & 0xffff;
     79 	bits[2] = L[_1];
     80 	bits[1] = L[_2];
     81 	bits[0] = L[_3];
     82 	b = buf;
     83 	if ( (ex = (L[_0] & 0x7fff0000L) >> 16) !=0) {
     84 		if (ex == 0x7fff) {
     85 			/* Infinity or NaN */
     86 			if (bits[0] | bits[1] | bits[2] | bits[3])
     87 				b = strcp(b, "NaN");
     88 			else {
     89 				b = buf;
     90 				if (sign)
     91 					*b++ = '-';
     92 				b = strcp(b, "Infinity");
     93 				}
     94 			return b;
     95 			}
     96 		i = STRTOG_Normal;
     97 		bits[3] |= 0x10000;
     98 		}
     99 	else if (bits[0] | bits[1] | bits[2] | bits[3]) {
    100 		i = STRTOG_Denormal;
    101 		ex = 1;
    102 		}
    103 	else {
    104 #ifndef IGNORE_ZERO_SIGN
    105 		if (sign)
    106 			*b++ = '-';
    107 #endif
    108 		*b++ = '0';
    109 		*b = 0;
    110 		return b;
    111 		}
    112 	ex -= 0x3fff + 112;
    113 	mode = 2;
    114 	if (ndig <= 0) {
    115 		if (bufsize < 48)
    116 			return 0;
    117 		mode = 0;
    118 		}
    119 	s = gdtoa(fpi, ex, bits, &i, mode, ndig, &decpt, &se);
    120 	if (s == NULL)
    121 		return NULL;
    122 	return g__fmt(buf, s, se, decpt, sign, bufsize);
    123 	}
    124