xref: /onnv-gate/usr/src/lib/libbc/libc/gen/common/gconvert.c (revision 0:68f95e015346)
1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate  * CDDL HEADER START
3*0Sstevel@tonic-gate  *
4*0Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate  * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate  * (the "License").  You may not use this file except in compliance
7*0Sstevel@tonic-gate  * with the License.
8*0Sstevel@tonic-gate  *
9*0Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate  * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate  * and limitations under the License.
13*0Sstevel@tonic-gate  *
14*0Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate  *
20*0Sstevel@tonic-gate  * CDDL HEADER END
21*0Sstevel@tonic-gate  */
22*0Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"
23*0Sstevel@tonic-gate 
24*0Sstevel@tonic-gate /*
25*0Sstevel@tonic-gate  * Copyright (c) 1988 by Sun Microsystems, Inc.
26*0Sstevel@tonic-gate  */
27*0Sstevel@tonic-gate 
28*0Sstevel@tonic-gate /*
29*0Sstevel@tonic-gate  * gcvt  - Floating output conversion to minimal length string
30*0Sstevel@tonic-gate  */
31*0Sstevel@tonic-gate 
32*0Sstevel@tonic-gate #include "base_conversion.h"
33*0Sstevel@tonic-gate #ifndef PRE41
34*0Sstevel@tonic-gate #include <locale.h>
35*0Sstevel@tonic-gate #endif
36*0Sstevel@tonic-gate 
37*0Sstevel@tonic-gate void
_gcvt(ndigit,pd,trailing,buf)38*0Sstevel@tonic-gate _gcvt(ndigit, pd, trailing, buf)
39*0Sstevel@tonic-gate 	int             ndigit;
40*0Sstevel@tonic-gate 	decimal_record *pd;
41*0Sstevel@tonic-gate 	char           *buf;
42*0Sstevel@tonic-gate {
43*0Sstevel@tonic-gate 	char           *p, *pstring;
44*0Sstevel@tonic-gate 	int             i;
45*0Sstevel@tonic-gate 	static char     *inf8 = "Infinity";
46*0Sstevel@tonic-gate 	static char     *inf3 = "Inf";
47*0Sstevel@tonic-gate 	static char     *nan = "NaN";
48*0Sstevel@tonic-gate #ifdef PRE41
49*0Sstevel@tonic-gate 	char decpt = '.';
50*0Sstevel@tonic-gate #else
51*0Sstevel@tonic-gate 	char decpt = *(localeconv()->decimal_point);
52*0Sstevel@tonic-gate #endif
53*0Sstevel@tonic-gate 
54*0Sstevel@tonic-gate 	p = buf;
55*0Sstevel@tonic-gate 	if (pd->sign)
56*0Sstevel@tonic-gate 		*(p++) = '-';
57*0Sstevel@tonic-gate 	switch (pd->fpclass) {
58*0Sstevel@tonic-gate 	case fp_zero:
59*0Sstevel@tonic-gate 		*(p++) = '0';
60*0Sstevel@tonic-gate 		if (trailing != 0) {
61*0Sstevel@tonic-gate 			*(p++) = decpt;
62*0Sstevel@tonic-gate 			for (i = 0; i < ndigit - 1; i++)
63*0Sstevel@tonic-gate 				*(p++) = '0';
64*0Sstevel@tonic-gate 		}
65*0Sstevel@tonic-gate 		break;
66*0Sstevel@tonic-gate 	case fp_infinity:
67*0Sstevel@tonic-gate 		if (ndigit < 8)
68*0Sstevel@tonic-gate 			pstring = inf3;
69*0Sstevel@tonic-gate 		else
70*0Sstevel@tonic-gate 			pstring = inf8;
71*0Sstevel@tonic-gate 		goto copystring;
72*0Sstevel@tonic-gate 	case fp_quiet:
73*0Sstevel@tonic-gate 	case fp_signaling:
74*0Sstevel@tonic-gate 		pstring = nan;
75*0Sstevel@tonic-gate copystring:
76*0Sstevel@tonic-gate 		for (i = 0; *pstring != 0;)
77*0Sstevel@tonic-gate 			*(p++) = *(pstring++);
78*0Sstevel@tonic-gate 		break;
79*0Sstevel@tonic-gate 	default:
80*0Sstevel@tonic-gate 		if ((pd->exponent > 0) || (pd->exponent < -(ndigit + 3))) {	/* E format. */
81*0Sstevel@tonic-gate 			char            estring[4];
82*0Sstevel@tonic-gate 			int             n;
83*0Sstevel@tonic-gate 
84*0Sstevel@tonic-gate 			i = 0;
85*0Sstevel@tonic-gate 			*(p++) = pd->ds[0];
86*0Sstevel@tonic-gate 			*(p++) = decpt;
87*0Sstevel@tonic-gate 			for (i = 1; pd->ds[i] != 0;)
88*0Sstevel@tonic-gate 				*(p++) = pd->ds[i++];
89*0Sstevel@tonic-gate 			if (trailing == 0) {	/* Remove trailing zeros and . */
90*0Sstevel@tonic-gate 				p--;
91*0Sstevel@tonic-gate 				while (*p == '0')
92*0Sstevel@tonic-gate 					p--;
93*0Sstevel@tonic-gate 				if (*p != decpt)
94*0Sstevel@tonic-gate 					p++;
95*0Sstevel@tonic-gate 			}
96*0Sstevel@tonic-gate 			*(p++) = 'e';
97*0Sstevel@tonic-gate 			n = pd->exponent + i - 1;
98*0Sstevel@tonic-gate 			if (n >= 0)
99*0Sstevel@tonic-gate 				*(p++) = '+';
100*0Sstevel@tonic-gate 			else {
101*0Sstevel@tonic-gate 				*(p++) = '-';
102*0Sstevel@tonic-gate 				n = -n;
103*0Sstevel@tonic-gate 			}
104*0Sstevel@tonic-gate 			_fourdigitsquick((short unsigned) n, estring);
105*0Sstevel@tonic-gate 			for (i = 0; estring[i] == '0'; i++);	/* Find end of zeros. */
106*0Sstevel@tonic-gate 			if (i > 2)
107*0Sstevel@tonic-gate 				i = 2;	/* Guarantee two zeros. */
108*0Sstevel@tonic-gate 			for (; i <= 3;)
109*0Sstevel@tonic-gate 				*(p++) = estring[i++];	/* Copy exp digits. */
110*0Sstevel@tonic-gate 		} else {	/* F format. */
111*0Sstevel@tonic-gate 			if (pd->exponent >= (1 - ndigit)) {	/* x.xxx */
112*0Sstevel@tonic-gate 				for (i = 0; i < (ndigit + pd->exponent);)
113*0Sstevel@tonic-gate 					*(p++) = pd->ds[i++];
114*0Sstevel@tonic-gate 				*(p++) = decpt;
115*0Sstevel@tonic-gate 				if (pd->ds[i] != 0) {	/* More follows point. */
116*0Sstevel@tonic-gate 					for (; i < ndigit;)
117*0Sstevel@tonic-gate 						*(p++) = pd->ds[i++];
118*0Sstevel@tonic-gate 				}
119*0Sstevel@tonic-gate 			} else {/* 0.00xxxx */
120*0Sstevel@tonic-gate 				*(p++) = '0';
121*0Sstevel@tonic-gate 				*(p++) = decpt;
122*0Sstevel@tonic-gate 				for (i = 0; i < -(pd->exponent + ndigit); i++)
123*0Sstevel@tonic-gate 					*(p++) = '0';
124*0Sstevel@tonic-gate 				for (i = 0; pd->ds[i] != 0;)
125*0Sstevel@tonic-gate 					*(p++) = pd->ds[i++];
126*0Sstevel@tonic-gate 			}
127*0Sstevel@tonic-gate 			if (trailing == 0) {	/* Remove trailing zeros and point. */
128*0Sstevel@tonic-gate 				p--;
129*0Sstevel@tonic-gate 				while (*p == '0')
130*0Sstevel@tonic-gate 					p--;
131*0Sstevel@tonic-gate 				if (*p != decpt)
132*0Sstevel@tonic-gate 					p++;
133*0Sstevel@tonic-gate 			}
134*0Sstevel@tonic-gate 		}
135*0Sstevel@tonic-gate 	}
136*0Sstevel@tonic-gate 	*(p++) = 0;
137*0Sstevel@tonic-gate }
138*0Sstevel@tonic-gate 
139*0Sstevel@tonic-gate char           *
gconvert(number,ndigit,trailing,buf)140*0Sstevel@tonic-gate gconvert(number, ndigit, trailing, buf)
141*0Sstevel@tonic-gate 	double          number;
142*0Sstevel@tonic-gate 	int             ndigit, trailing;
143*0Sstevel@tonic-gate 	char           *buf;
144*0Sstevel@tonic-gate {
145*0Sstevel@tonic-gate 	decimal_mode    dm;
146*0Sstevel@tonic-gate 	decimal_record  dr;
147*0Sstevel@tonic-gate 	fp_exception_field_type fef;
148*0Sstevel@tonic-gate 
149*0Sstevel@tonic-gate 	dm.rd = fp_direction;
150*0Sstevel@tonic-gate 	dm.df = floating_form;
151*0Sstevel@tonic-gate 	dm.ndigits = ndigit;
152*0Sstevel@tonic-gate 	double_to_decimal(&number, &dm, &dr, &fef);
153*0Sstevel@tonic-gate 	_gcvt(ndigit, &dr, trailing, buf);
154*0Sstevel@tonic-gate 	return (buf);
155*0Sstevel@tonic-gate }
156*0Sstevel@tonic-gate 
157*0Sstevel@tonic-gate char           *
gcvt(number,ndigit,buf)158*0Sstevel@tonic-gate gcvt(number, ndigit, buf)
159*0Sstevel@tonic-gate 	double          number;
160*0Sstevel@tonic-gate 	int             ndigit;
161*0Sstevel@tonic-gate 	char           *buf;
162*0Sstevel@tonic-gate {
163*0Sstevel@tonic-gate 	return (gconvert(number, ndigit, 0, buf));
164*0Sstevel@tonic-gate }
165