Home | History | Annotate | Line # | Download | only in gdtoa
g_Qfmt.c revision 1.1.1.2 
      1 /****************************************************************
      2 
      3 The author of this software is David M. Gay.
      4 
      5 Copyright (C) 1998, 2000 by Lucent Technologies
      6 All Rights Reserved
      7 
      8 Permission to use, copy, modify, and distribute this software and
      9 its documentation for any purpose and without fee is hereby
     10 granted, provided that the above copyright notice appear in all
     11 copies and that both that the copyright notice and this
     12 permission notice and warranty disclaimer appear in supporting
     13 documentation, and that the name of Lucent or any of its entities
     14 not be used in advertising or publicity pertaining to
     15 distribution of the software without specific, written prior
     16 permission.
     17 
     18 LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
     19 INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
     20 IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY
     21 SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
     22 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
     23 IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
     24 ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
     25 THIS SOFTWARE.
     26 
     27 ****************************************************************/
     28 
     29 /* Please send bug reports to David M. Gay (dmg at acm dot org,
     30  * with " at " changed at "@" and " dot " changed to ".").	*/
     31 
     32 #include "gdtoaimp.h"
     33 
     34 #undef _0
     35 #undef _1
     36 
     37 /* one or the other of IEEE_MC68k or IEEE_8087 should be #defined */
     38 
     39 #ifdef IEEE_MC68k
     40 #define _0 0
     41 #define _1 1
     42 #define _2 2
     43 #define _3 3
     44 #endif
     45 #ifdef IEEE_8087
     46 #define _0 3
     47 #define _1 2
     48 #define _2 1
     49 #define _3 0
     50 #endif
     51 
     52  char*
     53 #ifdef KR_headers
     54 g_Qfmt(buf, V, ndig, bufsize) char *buf; char *V; int ndig; size_t bufsize;
     55 #else
     56 g_Qfmt(char *buf, void *V, int ndig, size_t bufsize)
     57 #endif
     58 {
     59 	static FPI fpi0 = { 113, 1-16383-113+1, 32766 - 16383 - 113 + 1, 1, 0 };
     60 	char *b, *s, *se;
     61 	ULong bits[4], *L, sign;
     62 	int decpt, ex, i, mode;
     63 #ifdef Honor_FLT_ROUNDS
     64 #include "gdtoa_fltrnds.h"
     65 #else
     66 #define fpi &fpi0
     67 #endif
     68 
     69 	if (ndig < 0)
     70 		ndig = 0;
     71 	if (bufsize < ndig + 10)
     72 		return 0;
     73 
     74 	L = (ULong*)V;
     75 	sign = L[_0] & 0x80000000L;
     76 	bits[3] = L[_0] & 0xffff;
     77 	bits[2] = L[_1];
     78 	bits[1] = L[_2];
     79 	bits[0] = L[_3];
     80 	b = buf;
     81 	if ( (ex = (L[_0] & 0x7fff0000L) >> 16) !=0) {
     82 		if (ex == 0x7fff) {
     83 			/* Infinity or NaN */
     84 			if (bits[0] | bits[1] | bits[2] | bits[3])
     85 				b = strcp(b, "NaN");
     86 			else {
     87 				b = buf;
     88 				if (sign)
     89 					*b++ = '-';
     90 				b = strcp(b, "Infinity");
     91 				}
     92 			return b;
     93 			}
     94 		i = STRTOG_Normal;
     95 		bits[3] |= 0x10000;
     96 		}
     97 	else if (bits[0] | bits[1] | bits[2] | bits[3]) {
     98 		i = STRTOG_Denormal;
     99 		ex = 1;
    100 		}
    101 	else {
    102 #ifndef IGNORE_ZERO_SIGN
    103 		if (sign)
    104 			*b++ = '-';
    105 #endif
    106 		*b++ = '0';
    107 		*b = 0;
    108 		return b;
    109 		}
    110 	ex -= 0x3fff + 112;
    111 	mode = 2;
    112 	if (ndig <= 0) {
    113 		if (bufsize < 48)
    114 			return 0;
    115 		mode = 0;
    116 		}
    117 	s = gdtoa(fpi, ex, bits, &i, mode, ndig, &decpt, &se);
    118 	return g__fmt(buf, s, se, decpt, sign, bufsize);
    119 	}
    120