1 b2cfc4e2 2003-09-30 devnull /*
  2 b2cfc4e2 2003-09-30 devnull  * The authors of this software are Rob Pike and Ken Thompson.
  3 b2cfc4e2 2003-09-30 devnull  *              Copyright (c) 2002 by Lucent Technologies.
  4 b2cfc4e2 2003-09-30 devnull  * Permission to use, copy, modify, and distribute this software for any
  5 b2cfc4e2 2003-09-30 devnull  * purpose without fee is hereby granted, provided that this entire notice
  6 b2cfc4e2 2003-09-30 devnull  * is included in all copies of any software which is or includes a copy
  7 b2cfc4e2 2003-09-30 devnull  * or modification of this software and in all copies of the supporting
  8 b2cfc4e2 2003-09-30 devnull  * documentation for such software.
  9 b2cfc4e2 2003-09-30 devnull  * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED
 10 b2cfc4e2 2003-09-30 devnull  * WARRANTY.  IN PARTICULAR, NEITHER THE AUTHORS NOR LUCENT TECHNOLOGIES MAKE ANY
 11 b2cfc4e2 2003-09-30 devnull  * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE MERCHANTABILITY
 12 b2cfc4e2 2003-09-30 devnull  * OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR PURPOSE.
 13 b2cfc4e2 2003-09-30 devnull  */
 14 b2cfc4e2 2003-09-30 devnull #include <stdio.h>
 15 b2cfc4e2 2003-09-30 devnull #include <math.h>
 16 b2cfc4e2 2003-09-30 devnull #include <float.h>
 17 b2cfc4e2 2003-09-30 devnull #include <string.h>
 18 b2cfc4e2 2003-09-30 devnull #include <stdlib.h>
 19 b2cfc4e2 2003-09-30 devnull #include <errno.h>
 20 b2cfc4e2 2003-09-30 devnull #include <stdarg.h>
 21 b2cfc4e2 2003-09-30 devnull #include "fmt.h"
 22 b2cfc4e2 2003-09-30 devnull #include "fmtdef.h"
 23 b2cfc4e2 2003-09-30 devnull #include "nan.h"
 24 b2cfc4e2 2003-09-30 devnull 
 25 b2cfc4e2 2003-09-30 devnull enum
 26 b2cfc4e2 2003-09-30 devnull {
 27 b2cfc4e2 2003-09-30 devnull 	FDEFLT	= 6,
 28 b2cfc4e2 2003-09-30 devnull 	NSIGNIF	= 17
 29 b2cfc4e2 2003-09-30 devnull };
 30 b2cfc4e2 2003-09-30 devnull 
 31 b2cfc4e2 2003-09-30 devnull /*
 32 b2cfc4e2 2003-09-30 devnull  * first few powers of 10, enough for about 1/2 of the
 33 b2cfc4e2 2003-09-30 devnull  * total space for doubles.
 34 b2cfc4e2 2003-09-30 devnull  */
 35 b2cfc4e2 2003-09-30 devnull static double pows10[] =
 36 b2cfc4e2 2003-09-30 devnull {
 37 b2cfc4e2 2003-09-30 devnull 	  1e0,   1e1,   1e2,   1e3,   1e4,   1e5,   1e6,   1e7,   1e8,   1e9,  
 38 b2cfc4e2 2003-09-30 devnull 	 1e10,  1e11,  1e12,  1e13,  1e14,  1e15,  1e16,  1e17,  1e18,  1e19,  
 39 b2cfc4e2 2003-09-30 devnull 	 1e20,  1e21,  1e22,  1e23,  1e24,  1e25,  1e26,  1e27,  1e28,  1e29,  
 40 b2cfc4e2 2003-09-30 devnull 	 1e30,  1e31,  1e32,  1e33,  1e34,  1e35,  1e36,  1e37,  1e38,  1e39,  
 41 b2cfc4e2 2003-09-30 devnull 	 1e40,  1e41,  1e42,  1e43,  1e44,  1e45,  1e46,  1e47,  1e48,  1e49,  
 42 b2cfc4e2 2003-09-30 devnull 	 1e50,  1e51,  1e52,  1e53,  1e54,  1e55,  1e56,  1e57,  1e58,  1e59,  
 43 b2cfc4e2 2003-09-30 devnull 	 1e60,  1e61,  1e62,  1e63,  1e64,  1e65,  1e66,  1e67,  1e68,  1e69,  
 44 b2cfc4e2 2003-09-30 devnull 	 1e70,  1e71,  1e72,  1e73,  1e74,  1e75,  1e76,  1e77,  1e78,  1e79,  
 45 b2cfc4e2 2003-09-30 devnull 	 1e80,  1e81,  1e82,  1e83,  1e84,  1e85,  1e86,  1e87,  1e88,  1e89,  
 46 b2cfc4e2 2003-09-30 devnull 	 1e90,  1e91,  1e92,  1e93,  1e94,  1e95,  1e96,  1e97,  1e98,  1e99,  
 47 b2cfc4e2 2003-09-30 devnull 	1e100, 1e101, 1e102, 1e103, 1e104, 1e105, 1e106, 1e107, 1e108, 1e109, 
 48 b2cfc4e2 2003-09-30 devnull 	1e110, 1e111, 1e112, 1e113, 1e114, 1e115, 1e116, 1e117, 1e118, 1e119, 
 49 b2cfc4e2 2003-09-30 devnull 	1e120, 1e121, 1e122, 1e123, 1e124, 1e125, 1e126, 1e127, 1e128, 1e129, 
 50 b2cfc4e2 2003-09-30 devnull 	1e130, 1e131, 1e132, 1e133, 1e134, 1e135, 1e136, 1e137, 1e138, 1e139, 
 51 b2cfc4e2 2003-09-30 devnull 	1e140, 1e141, 1e142, 1e143, 1e144, 1e145, 1e146, 1e147, 1e148, 1e149, 
 52 b2cfc4e2 2003-09-30 devnull 	1e150, 1e151, 1e152, 1e153, 1e154, 1e155, 1e156, 1e157, 1e158, 1e159, 
 53 b2cfc4e2 2003-09-30 devnull };
 54 b2cfc4e2 2003-09-30 devnull 
 55 b2cfc4e2 2003-09-30 devnull static double
 56 b2cfc4e2 2003-09-30 devnull pow10(int n)
 57 b2cfc4e2 2003-09-30 devnull {
 58 b2cfc4e2 2003-09-30 devnull 	double d;
 59 b2cfc4e2 2003-09-30 devnull 	int neg;
 60 b2cfc4e2 2003-09-30 devnull 
 61 b2cfc4e2 2003-09-30 devnull 	neg = 0;
 62 b2cfc4e2 2003-09-30 devnull 	if(n < 0){
 63 b2cfc4e2 2003-09-30 devnull 		if(n < DBL_MIN_10_EXP){
 64 b2cfc4e2 2003-09-30 devnull 			return 0.;
 65 b2cfc4e2 2003-09-30 devnull 		}
 66 b2cfc4e2 2003-09-30 devnull 		neg = 1;
 67 b2cfc4e2 2003-09-30 devnull 		n = -n;
 68 b2cfc4e2 2003-09-30 devnull 	}else if(n > DBL_MAX_10_EXP){
 69 b2cfc4e2 2003-09-30 devnull 		return HUGE_VAL;
 70 b2cfc4e2 2003-09-30 devnull 	}
 71 b2cfc4e2 2003-09-30 devnull 	if(n < (int)(sizeof(pows10)/sizeof(pows10[0])))
 72 b2cfc4e2 2003-09-30 devnull 		d = pows10[n];
 73 b2cfc4e2 2003-09-30 devnull 	else{
 74 b2cfc4e2 2003-09-30 devnull 		d = pows10[sizeof(pows10)/sizeof(pows10[0]) - 1];
 75 b2cfc4e2 2003-09-30 devnull 		for(;;){
 76 b2cfc4e2 2003-09-30 devnull 			n -= sizeof(pows10)/sizeof(pows10[0]) - 1;
 77 b2cfc4e2 2003-09-30 devnull 			if(n < (int)(sizeof(pows10)/sizeof(pows10[0]))){
 78 b2cfc4e2 2003-09-30 devnull 				d *= pows10[n];
 79 b2cfc4e2 2003-09-30 devnull 				break;
 80 b2cfc4e2 2003-09-30 devnull 			}
 81 b2cfc4e2 2003-09-30 devnull 			d *= pows10[sizeof(pows10)/sizeof(pows10[0]) - 1];
 82 b2cfc4e2 2003-09-30 devnull 		}
 83 b2cfc4e2 2003-09-30 devnull 	}
 84 b2cfc4e2 2003-09-30 devnull 	if(neg){
 85 b2cfc4e2 2003-09-30 devnull 		return 1./d;
 86 b2cfc4e2 2003-09-30 devnull 	}
 87 b2cfc4e2 2003-09-30 devnull 	return d;
 88 b2cfc4e2 2003-09-30 devnull }
 89 b2cfc4e2 2003-09-30 devnull 
 90 b2cfc4e2 2003-09-30 devnull static int
 91 b2cfc4e2 2003-09-30 devnull xadd(char *a, int n, int v)
 92 b2cfc4e2 2003-09-30 devnull {
 93 b2cfc4e2 2003-09-30 devnull 	char *b;
 94 b2cfc4e2 2003-09-30 devnull 	int c;
 95 b2cfc4e2 2003-09-30 devnull 
 96 b2cfc4e2 2003-09-30 devnull 	if(n < 0 || n >= NSIGNIF)
 97 b2cfc4e2 2003-09-30 devnull 		return 0;
 98 b2cfc4e2 2003-09-30 devnull 	for(b = a+n; b >= a; b--) {
 99 b2cfc4e2 2003-09-30 devnull 		c = *b + v;
100 b2cfc4e2 2003-09-30 devnull 		if(c <= '9') {
101 b2cfc4e2 2003-09-30 devnull 			*b = c;
102 b2cfc4e2 2003-09-30 devnull 			return 0;
103 b2cfc4e2 2003-09-30 devnull 		}
104 b2cfc4e2 2003-09-30 devnull 		*b = '0';
105 b2cfc4e2 2003-09-30 devnull 		v = 1;
106 b2cfc4e2 2003-09-30 devnull 	}
107 b2cfc4e2 2003-09-30 devnull 	*a = '1';	/* overflow adding */
108 b2cfc4e2 2003-09-30 devnull 	return 1;
109 b2cfc4e2 2003-09-30 devnull }
110 b2cfc4e2 2003-09-30 devnull 
111 b2cfc4e2 2003-09-30 devnull static int
112 b2cfc4e2 2003-09-30 devnull xsub(char *a, int n, int v)
113 b2cfc4e2 2003-09-30 devnull {
114 b2cfc4e2 2003-09-30 devnull 	char *b;
115 b2cfc4e2 2003-09-30 devnull 	int c;
116 b2cfc4e2 2003-09-30 devnull 
117 b2cfc4e2 2003-09-30 devnull 	for(b = a+n; b >= a; b--) {
118 b2cfc4e2 2003-09-30 devnull 		c = *b - v;
119 b2cfc4e2 2003-09-30 devnull 		if(c >= '0') {
120 b2cfc4e2 2003-09-30 devnull 			*b = c;
121 b2cfc4e2 2003-09-30 devnull 			return 0;
122 b2cfc4e2 2003-09-30 devnull 		}
123 b2cfc4e2 2003-09-30 devnull 		*b = '9';
124 b2cfc4e2 2003-09-30 devnull 		v = 1;
125 b2cfc4e2 2003-09-30 devnull 	}
126 b2cfc4e2 2003-09-30 devnull 	*a = '9';	/* underflow subtracting */
127 b2cfc4e2 2003-09-30 devnull 	return 1;
128 b2cfc4e2 2003-09-30 devnull }
129 b2cfc4e2 2003-09-30 devnull 
130 b2cfc4e2 2003-09-30 devnull static void
131 b2cfc4e2 2003-09-30 devnull xaddexp(char *p, int e)
132 b2cfc4e2 2003-09-30 devnull {
133 b2cfc4e2 2003-09-30 devnull 	char se[9];
134 b2cfc4e2 2003-09-30 devnull 	int i;
135 b2cfc4e2 2003-09-30 devnull 
136 b2cfc4e2 2003-09-30 devnull 	*p++ = 'e';
137 b2cfc4e2 2003-09-30 devnull 	if(e < 0) {
138 b2cfc4e2 2003-09-30 devnull 		*p++ = '-';
139 b2cfc4e2 2003-09-30 devnull 		e = -e;
140 b2cfc4e2 2003-09-30 devnull 	}
141 b2cfc4e2 2003-09-30 devnull 	i = 0;
142 b2cfc4e2 2003-09-30 devnull 	while(e) {
143 b2cfc4e2 2003-09-30 devnull 		se[i++] = e % 10 + '0';
144 b2cfc4e2 2003-09-30 devnull 		e /= 10;
145 b2cfc4e2 2003-09-30 devnull 	}
146 b2cfc4e2 2003-09-30 devnull 	if(i == 0) {
147 b2cfc4e2 2003-09-30 devnull 		*p++ = '0';
148 b2cfc4e2 2003-09-30 devnull 	} else {
149 b2cfc4e2 2003-09-30 devnull 		while(i > 0)
150 b2cfc4e2 2003-09-30 devnull 			*p++ = se[--i];
151 b2cfc4e2 2003-09-30 devnull 	}
152 b2cfc4e2 2003-09-30 devnull 	*p++ = '\0';
153 b2cfc4e2 2003-09-30 devnull }
154 b2cfc4e2 2003-09-30 devnull 
155 b2cfc4e2 2003-09-30 devnull static char*
156 b2cfc4e2 2003-09-30 devnull xdodtoa(char *s1, double f, int chr, int prec, int *decpt, int *rsign)
157 b2cfc4e2 2003-09-30 devnull {
158 b2cfc4e2 2003-09-30 devnull 	char s2[NSIGNIF+10];
159 b2cfc4e2 2003-09-30 devnull 	double g, h;
160 b2cfc4e2 2003-09-30 devnull 	int e, d, i;
161 b2cfc4e2 2003-09-30 devnull 	int c2, sign, oerr;
162 b2cfc4e2 2003-09-30 devnull 
163 b2cfc4e2 2003-09-30 devnull 	if(chr == 'F')
164 b2cfc4e2 2003-09-30 devnull 		chr = 'f';
165 b2cfc4e2 2003-09-30 devnull 	if(prec > NSIGNIF)
166 b2cfc4e2 2003-09-30 devnull 		prec = NSIGNIF;
167 b2cfc4e2 2003-09-30 devnull 	if(prec < 0)
168 b2cfc4e2 2003-09-30 devnull 		prec = 0;
169 b2cfc4e2 2003-09-30 devnull 	if(__isNaN(f)) {
170 b2cfc4e2 2003-09-30 devnull 		*decpt = 9999;
171 b2cfc4e2 2003-09-30 devnull 		*rsign = 0;
172 b2cfc4e2 2003-09-30 devnull 		strcpy(s1, "nan");
173 b2cfc4e2 2003-09-30 devnull 		return &s1[3];
174 b2cfc4e2 2003-09-30 devnull 	}
175 b2cfc4e2 2003-09-30 devnull 	sign = 0;
176 b2cfc4e2 2003-09-30 devnull 	if(f < 0) {
177 b2cfc4e2 2003-09-30 devnull 		f = -f;
178 b2cfc4e2 2003-09-30 devnull 		sign++;
179 b2cfc4e2 2003-09-30 devnull 	}
180 b2cfc4e2 2003-09-30 devnull 	*rsign = sign;
181 b2cfc4e2 2003-09-30 devnull 	if(__isInf(f, 1) || __isInf(f, -1)) {
182 b2cfc4e2 2003-09-30 devnull 		*decpt = 9999;
183 b2cfc4e2 2003-09-30 devnull 		strcpy(s1, "inf");
184 b2cfc4e2 2003-09-30 devnull 		return &s1[3];
185 b2cfc4e2 2003-09-30 devnull 	}
186 b2cfc4e2 2003-09-30 devnull 
187 b2cfc4e2 2003-09-30 devnull 	e = 0;
188 b2cfc4e2 2003-09-30 devnull 	g = f;
189 b2cfc4e2 2003-09-30 devnull 	if(g != 0) {
190 b2cfc4e2 2003-09-30 devnull 		frexp(f, &e);
191 b2cfc4e2 2003-09-30 devnull 		e = (int)(e * .301029995664);
192 b2cfc4e2 2003-09-30 devnull 		if(e >= -150 && e <= +150) {
193 b2cfc4e2 2003-09-30 devnull 			d = 0;
194 b2cfc4e2 2003-09-30 devnull 			h = f;
195 b2cfc4e2 2003-09-30 devnull 		} else {
196 b2cfc4e2 2003-09-30 devnull 			d = e/2;
197 b2cfc4e2 2003-09-30 devnull 			h = f * pow10(-d);
198 b2cfc4e2 2003-09-30 devnull 		}
199 b2cfc4e2 2003-09-30 devnull 		g = h * pow10(d-e);
200 b2cfc4e2 2003-09-30 devnull 		while(g < 1) {
201 b2cfc4e2 2003-09-30 devnull 			e--;
202 b2cfc4e2 2003-09-30 devnull 			g = h * pow10(d-e);
203 b2cfc4e2 2003-09-30 devnull 		}
204 b2cfc4e2 2003-09-30 devnull 		while(g >= 10) {
205 b2cfc4e2 2003-09-30 devnull 			e++;
206 b2cfc4e2 2003-09-30 devnull 			g = h * pow10(d-e);
207 b2cfc4e2 2003-09-30 devnull 		}
208 b2cfc4e2 2003-09-30 devnull 	}
209 b2cfc4e2 2003-09-30 devnull 
210 b2cfc4e2 2003-09-30 devnull 	/*
211 b2cfc4e2 2003-09-30 devnull 	 * convert NSIGNIF digits and convert
212 b2cfc4e2 2003-09-30 devnull 	 * back to get accuracy.
213 b2cfc4e2 2003-09-30 devnull 	 */
214 b2cfc4e2 2003-09-30 devnull 	for(i=0; i<NSIGNIF; i++) {
215 b2cfc4e2 2003-09-30 devnull 		d = (int)g;
216 b2cfc4e2 2003-09-30 devnull 		s1[i] = d + '0';
217 b2cfc4e2 2003-09-30 devnull 		g = (g - d) * 10;
218 b2cfc4e2 2003-09-30 devnull 	}
219 b2cfc4e2 2003-09-30 devnull 	s1[i] = 0;
220 b2cfc4e2 2003-09-30 devnull 
221 b2cfc4e2 2003-09-30 devnull 	/*
222 b2cfc4e2 2003-09-30 devnull 	 * try decimal rounding to eliminate 9s
223 b2cfc4e2 2003-09-30 devnull 	 */
224 b2cfc4e2 2003-09-30 devnull 	c2 = prec + 1;
225 b2cfc4e2 2003-09-30 devnull 	if(chr == 'f')
226 b2cfc4e2 2003-09-30 devnull 		c2 += e;
227 b2cfc4e2 2003-09-30 devnull 	oerr = errno;
228 b2cfc4e2 2003-09-30 devnull 	if(c2 >= NSIGNIF-2) {
229 b2cfc4e2 2003-09-30 devnull 		strcpy(s2, s1);
230 b2cfc4e2 2003-09-30 devnull 		d = e;
231 b2cfc4e2 2003-09-30 devnull 		s1[NSIGNIF-2] = '0';
232 b2cfc4e2 2003-09-30 devnull 		s1[NSIGNIF-1] = '0';
233 b2cfc4e2 2003-09-30 devnull 		xaddexp(s1+NSIGNIF, e-NSIGNIF+1);
234 b2cfc4e2 2003-09-30 devnull 		g = fmtstrtod(s1, nil);
235 b2cfc4e2 2003-09-30 devnull 		if(g == f)
236 b2cfc4e2 2003-09-30 devnull 			goto found;
237 b2cfc4e2 2003-09-30 devnull 		if(xadd(s1, NSIGNIF-3, 1)) {
238 b2cfc4e2 2003-09-30 devnull 			e++;
239 b2cfc4e2 2003-09-30 devnull 			xaddexp(s1+NSIGNIF, e-NSIGNIF+1);
240 b2cfc4e2 2003-09-30 devnull 		}
241 b2cfc4e2 2003-09-30 devnull 		g = fmtstrtod(s1, nil);
242 b2cfc4e2 2003-09-30 devnull 		if(g == f)
243 b2cfc4e2 2003-09-30 devnull 			goto found;
244 b2cfc4e2 2003-09-30 devnull 		strcpy(s1, s2);
245 b2cfc4e2 2003-09-30 devnull 		e = d;
246 b2cfc4e2 2003-09-30 devnull 	}
247 b2cfc4e2 2003-09-30 devnull 
248 b2cfc4e2 2003-09-30 devnull 	/*
249 b2cfc4e2 2003-09-30 devnull 	 * convert back so s1 gets exact answer
250 b2cfc4e2 2003-09-30 devnull 	 */
251 b2cfc4e2 2003-09-30 devnull 	for(d = 0; d < 10; d++) {
252 b2cfc4e2 2003-09-30 devnull 		xaddexp(s1+NSIGNIF, e-NSIGNIF+1);
253 b2cfc4e2 2003-09-30 devnull 		g = fmtstrtod(s1, nil);
254 b2cfc4e2 2003-09-30 devnull 		if(f > g) {
255 b2cfc4e2 2003-09-30 devnull 			if(xadd(s1, NSIGNIF-1, 1))
256 b2cfc4e2 2003-09-30 devnull 				e--;
257 b2cfc4e2 2003-09-30 devnull 			continue;
258 b2cfc4e2 2003-09-30 devnull 		}
259 b2cfc4e2 2003-09-30 devnull 		if(f < g) {
260 b2cfc4e2 2003-09-30 devnull 			if(xsub(s1, NSIGNIF-1, 1))
261 b2cfc4e2 2003-09-30 devnull 				e++;
262 b2cfc4e2 2003-09-30 devnull 			continue;
263 b2cfc4e2 2003-09-30 devnull 		}
264 b2cfc4e2 2003-09-30 devnull 		break;
265 b2cfc4e2 2003-09-30 devnull 	}
266 b2cfc4e2 2003-09-30 devnull 
267 b2cfc4e2 2003-09-30 devnull found:
268 b2cfc4e2 2003-09-30 devnull 	errno = oerr;
269 b2cfc4e2 2003-09-30 devnull 
270 b2cfc4e2 2003-09-30 devnull 	/*
271 b2cfc4e2 2003-09-30 devnull 	 * sign
272 b2cfc4e2 2003-09-30 devnull 	 */
273 b2cfc4e2 2003-09-30 devnull 	d = 0;
274 b2cfc4e2 2003-09-30 devnull 	i = 0;
275 b2cfc4e2 2003-09-30 devnull 
276 b2cfc4e2 2003-09-30 devnull 	/*
277 b2cfc4e2 2003-09-30 devnull 	 * round & adjust 'f' digits
278 b2cfc4e2 2003-09-30 devnull 	 */
279 b2cfc4e2 2003-09-30 devnull 	c2 = prec + 1;
280 b2cfc4e2 2003-09-30 devnull 	if(chr == 'f'){
281 b2cfc4e2 2003-09-30 devnull 		if(xadd(s1, c2+e, 5))
282 b2cfc4e2 2003-09-30 devnull 			e++;
283 b2cfc4e2 2003-09-30 devnull 		c2 += e;
284 b2cfc4e2 2003-09-30 devnull 		if(c2 < 0){
285 b2cfc4e2 2003-09-30 devnull 			c2 = 0;
286 b2cfc4e2 2003-09-30 devnull 			e = -prec - 1;
287 b2cfc4e2 2003-09-30 devnull 		}
288 b2cfc4e2 2003-09-30 devnull 	}else{
289 b2cfc4e2 2003-09-30 devnull 		if(xadd(s1, c2, 5))
290 b2cfc4e2 2003-09-30 devnull 			e++;
291 b2cfc4e2 2003-09-30 devnull 	}
292 b2cfc4e2 2003-09-30 devnull 	if(c2 > NSIGNIF){
293 b2cfc4e2 2003-09-30 devnull 		c2 = NSIGNIF;
294 b2cfc4e2 2003-09-30 devnull 	}
295 b2cfc4e2 2003-09-30 devnull 
296 b2cfc4e2 2003-09-30 devnull 	*decpt = e + 1;
297 b2cfc4e2 2003-09-30 devnull 
298 b2cfc4e2 2003-09-30 devnull 	/*
299 b2cfc4e2 2003-09-30 devnull 	 * terminate the converted digits
300 b2cfc4e2 2003-09-30 devnull 	 */
301 b2cfc4e2 2003-09-30 devnull 	s1[c2] = '\0';
302 b2cfc4e2 2003-09-30 devnull 	return &s1[c2];
303 b2cfc4e2 2003-09-30 devnull }
304 b2cfc4e2 2003-09-30 devnull 
305 b2cfc4e2 2003-09-30 devnull /*
306 b2cfc4e2 2003-09-30 devnull  * this function works like the standard dtoa, if you want it.
307 b2cfc4e2 2003-09-30 devnull  */
308 b2cfc4e2 2003-09-30 devnull #if 0
309 b2cfc4e2 2003-09-30 devnull static char*
310 b2cfc4e2 2003-09-30 devnull __dtoa(double f, int mode, int ndigits, int *decpt, int *rsign, char **rve)
311 b2cfc4e2 2003-09-30 devnull {
312 b2cfc4e2 2003-09-30 devnull 	static char s2[NSIGNIF + 10];
313 b2cfc4e2 2003-09-30 devnull 	char *es;
314 b2cfc4e2 2003-09-30 devnull 	int chr, prec;
315 b2cfc4e2 2003-09-30 devnull 
316 b2cfc4e2 2003-09-30 devnull 	switch(mode) {
317 b2cfc4e2 2003-09-30 devnull 	/* like 'e' */
318 b2cfc4e2 2003-09-30 devnull 	case 2:
319 b2cfc4e2 2003-09-30 devnull 	case 4:
320 b2cfc4e2 2003-09-30 devnull 	case 6:
321 b2cfc4e2 2003-09-30 devnull 	case 8:
322 b2cfc4e2 2003-09-30 devnull 		chr = 'e';
323 b2cfc4e2 2003-09-30 devnull 		break;
324 b2cfc4e2 2003-09-30 devnull 	/* like 'g' */
325 b2cfc4e2 2003-09-30 devnull 	case 0:
326 b2cfc4e2 2003-09-30 devnull 	case 1:
327 b2cfc4e2 2003-09-30 devnull 	default:
328 b2cfc4e2 2003-09-30 devnull 		chr = 'g';
329 b2cfc4e2 2003-09-30 devnull 		break;
330 b2cfc4e2 2003-09-30 devnull 	/* like 'f' */
331 b2cfc4e2 2003-09-30 devnull 	case 3:
332 b2cfc4e2 2003-09-30 devnull 	case 5:
333 b2cfc4e2 2003-09-30 devnull 	case 7:
334 b2cfc4e2 2003-09-30 devnull 	case 9:
335 b2cfc4e2 2003-09-30 devnull 		chr = 'f';
336 b2cfc4e2 2003-09-30 devnull 		break;
337 b2cfc4e2 2003-09-30 devnull 	}
338 b2cfc4e2 2003-09-30 devnull 
339 b2cfc4e2 2003-09-30 devnull 	if(chr != 'f' && ndigits){
340 b2cfc4e2 2003-09-30 devnull 		ndigits--;
341 b2cfc4e2 2003-09-30 devnull 	}
342 b2cfc4e2 2003-09-30 devnull 	prec = ndigits;
343 b2cfc4e2 2003-09-30 devnull 	if(prec > NSIGNIF)
344 b2cfc4e2 2003-09-30 devnull 		prec = NSIGNIF;
345 b2cfc4e2 2003-09-30 devnull 	if(ndigits == 0)
346 b2cfc4e2 2003-09-30 devnull 		prec = NSIGNIF;
347 b2cfc4e2 2003-09-30 devnull 	es = xdodtoa(s2, f, chr, prec, decpt, rsign);
348 b2cfc4e2 2003-09-30 devnull 
349 b2cfc4e2 2003-09-30 devnull 	/*
350 b2cfc4e2 2003-09-30 devnull 	 * strip trailing 0
351 b2cfc4e2 2003-09-30 devnull 	 */
352 b2cfc4e2 2003-09-30 devnull 	for(; es > s2 + 1; es--){
353 b2cfc4e2 2003-09-30 devnull 		if(es[-1] != '0'){
354 b2cfc4e2 2003-09-30 devnull 			break;
355 b2cfc4e2 2003-09-30 devnull 		}
356 b2cfc4e2 2003-09-30 devnull 	}
357 b2cfc4e2 2003-09-30 devnull 	*es = '\0';
358 b2cfc4e2 2003-09-30 devnull 	if(rve != NULL)
359 b2cfc4e2 2003-09-30 devnull 		*rve = es;
360 b2cfc4e2 2003-09-30 devnull 	return s2;
361 b2cfc4e2 2003-09-30 devnull }
362 b2cfc4e2 2003-09-30 devnull #endif
363 b2cfc4e2 2003-09-30 devnull 
364 b2cfc4e2 2003-09-30 devnull static int
365 b2cfc4e2 2003-09-30 devnull fmtzdotpad(Fmt *f, int n, int pt)
366 b2cfc4e2 2003-09-30 devnull {
367 b2cfc4e2 2003-09-30 devnull 	char *t, *s;
368 b2cfc4e2 2003-09-30 devnull 	int i;
369 b2cfc4e2 2003-09-30 devnull 	Rune *rt, *rs;
370 b2cfc4e2 2003-09-30 devnull 
371 b2cfc4e2 2003-09-30 devnull 	if(f->runes){
372 b2cfc4e2 2003-09-30 devnull 		rt = (Rune*)f->to;
373 b2cfc4e2 2003-09-30 devnull 		rs = (Rune*)f->stop;
374 b2cfc4e2 2003-09-30 devnull 		for(i = 0; i < n; i++){
375 b2cfc4e2 2003-09-30 devnull 			if(i == pt){
376 b2cfc4e2 2003-09-30 devnull 				FMTRCHAR(f, rt, rs, '.');
377 b2cfc4e2 2003-09-30 devnull 			}
378 b2cfc4e2 2003-09-30 devnull 			FMTRCHAR(f, rt, rs, '0');
379 b2cfc4e2 2003-09-30 devnull 		}
380 b2cfc4e2 2003-09-30 devnull 		f->nfmt += rt - (Rune*)f->to;
381 b2cfc4e2 2003-09-30 devnull 		f->to = rt;
382 b2cfc4e2 2003-09-30 devnull 	}else{
383 b2cfc4e2 2003-09-30 devnull 		t = (char*)f->to;
384 b2cfc4e2 2003-09-30 devnull 		s = (char*)f->stop;
385 b2cfc4e2 2003-09-30 devnull 		for(i = 0; i < n; i++){
386 b2cfc4e2 2003-09-30 devnull 			if(i == pt){
387 b2cfc4e2 2003-09-30 devnull 				FMTCHAR(f, t, s, '.');
388 b2cfc4e2 2003-09-30 devnull 			}
389 b2cfc4e2 2003-09-30 devnull 			FMTCHAR(f, t, s, '0');
390 b2cfc4e2 2003-09-30 devnull 		}
391 b2cfc4e2 2003-09-30 devnull 		f->nfmt += t - (char *)f->to;
392 b2cfc4e2 2003-09-30 devnull 		f->to = t;
393 b2cfc4e2 2003-09-30 devnull 	}
394 b2cfc4e2 2003-09-30 devnull 	return 0;
395 b2cfc4e2 2003-09-30 devnull }
396 b2cfc4e2 2003-09-30 devnull 
397 b2cfc4e2 2003-09-30 devnull int
398 b2cfc4e2 2003-09-30 devnull __efgfmt(Fmt *fmt)
399 b2cfc4e2 2003-09-30 devnull {
400 b2cfc4e2 2003-09-30 devnull 	double f;
401 b2cfc4e2 2003-09-30 devnull 	char s1[NSIGNIF+10];
402 b2cfc4e2 2003-09-30 devnull 	int e, d, n;
403 b2cfc4e2 2003-09-30 devnull 	int c1, c2, c3, c4, ucase, sign, chr, prec, fl;
404 b2cfc4e2 2003-09-30 devnull 
405 b2cfc4e2 2003-09-30 devnull 	f = va_arg(fmt->args, double);
406 b2cfc4e2 2003-09-30 devnull 	prec = FDEFLT;
407 b2cfc4e2 2003-09-30 devnull 	fl = fmt->flags;
408 b2cfc4e2 2003-09-30 devnull 	fmt->flags = 0;
409 b2cfc4e2 2003-09-30 devnull 	if(fl & FmtPrec)
410 b2cfc4e2 2003-09-30 devnull 		prec = fmt->prec;
411 b2cfc4e2 2003-09-30 devnull 	chr = fmt->r;
412 b2cfc4e2 2003-09-30 devnull 	ucase = 0;
413 b2cfc4e2 2003-09-30 devnull 	if(chr == 'E'){
414 b2cfc4e2 2003-09-30 devnull 		chr = 'e';
415 b2cfc4e2 2003-09-30 devnull 		ucase = 1;
416 b2cfc4e2 2003-09-30 devnull 	}else if(chr == 'F'){
417 b2cfc4e2 2003-09-30 devnull 		chr = 'f';
418 b2cfc4e2 2003-09-30 devnull 		ucase = 1;
419 b2cfc4e2 2003-09-30 devnull 	}else if(chr == 'G'){
420 b2cfc4e2 2003-09-30 devnull 		chr = 'g';
421 b2cfc4e2 2003-09-30 devnull 		ucase = 1;
422 b2cfc4e2 2003-09-30 devnull 	}
423 b2cfc4e2 2003-09-30 devnull 	if(prec > 0 && chr == 'g')
424 b2cfc4e2 2003-09-30 devnull 		prec--;
425 b2cfc4e2 2003-09-30 devnull 	if(prec < 0)
426 b2cfc4e2 2003-09-30 devnull 		prec = 0;
427 b2cfc4e2 2003-09-30 devnull 
428 b2cfc4e2 2003-09-30 devnull 	xdodtoa(s1, f, chr, prec, &e, &sign);
429 b2cfc4e2 2003-09-30 devnull 	e--;
430 b2cfc4e2 2003-09-30 devnull 	if(*s1 == 'i' || *s1 == 'n'){
431 b2cfc4e2 2003-09-30 devnull 		if(ucase){
432 b2cfc4e2 2003-09-30 devnull 			if(*s1 == 'i'){
433 b2cfc4e2 2003-09-30 devnull 				strcpy(s1, "INF");
434 b2cfc4e2 2003-09-30 devnull 			}else{
435 b2cfc4e2 2003-09-30 devnull 				strcpy(s1, "NAN");
436 b2cfc4e2 2003-09-30 devnull 			}
437 b2cfc4e2 2003-09-30 devnull 		}
438 b2cfc4e2 2003-09-30 devnull 		fmt->flags = fl & (FmtWidth|FmtLeft);
439 b2cfc4e2 2003-09-30 devnull 		return __fmtcpy(fmt, (const void*)s1, 3, 3);
440 b2cfc4e2 2003-09-30 devnull 	}
441 b2cfc4e2 2003-09-30 devnull 
442 b2cfc4e2 2003-09-30 devnull 	/*
443 b2cfc4e2 2003-09-30 devnull 	 * copy into final place
444 b2cfc4e2 2003-09-30 devnull 	 * c1 digits of leading '0'
445 b2cfc4e2 2003-09-30 devnull 	 * c2 digits from conversion
446 b2cfc4e2 2003-09-30 devnull 	 * c3 digits of trailing '0'
447 b2cfc4e2 2003-09-30 devnull 	 * c4 digits after '.'
448 b2cfc4e2 2003-09-30 devnull 	 */
449 b2cfc4e2 2003-09-30 devnull 	c1 = 0;
450 b2cfc4e2 2003-09-30 devnull 	c2 = prec + 1;
451 b2cfc4e2 2003-09-30 devnull 	c3 = 0;
452 b2cfc4e2 2003-09-30 devnull 	c4 = prec;
453 b2cfc4e2 2003-09-30 devnull 	switch(chr) {
454 b2cfc4e2 2003-09-30 devnull 	default:
455 b2cfc4e2 2003-09-30 devnull 		chr = 'e';
456 b2cfc4e2 2003-09-30 devnull 		break;
457 b2cfc4e2 2003-09-30 devnull 	case 'g':
458 b2cfc4e2 2003-09-30 devnull 		/*
459 b2cfc4e2 2003-09-30 devnull 		 * decide on 'e' of 'f' style convers
460 b2cfc4e2 2003-09-30 devnull 		 */
461 b2cfc4e2 2003-09-30 devnull 		if(e >= -4 && e <= prec) {
462 b2cfc4e2 2003-09-30 devnull 			c1 = -e;
463 b2cfc4e2 2003-09-30 devnull 			c4 = prec - e;
464 b2cfc4e2 2003-09-30 devnull 			chr = 'h';	/* flag for 'f' style */
465 b2cfc4e2 2003-09-30 devnull 		}
466 b2cfc4e2 2003-09-30 devnull 		break;
467 b2cfc4e2 2003-09-30 devnull 	case 'f':
468 b2cfc4e2 2003-09-30 devnull 		c1 = -e;
469 b2cfc4e2 2003-09-30 devnull 		if(c1 > prec)
470 b2cfc4e2 2003-09-30 devnull 			c1 = prec + 1;
471 b2cfc4e2 2003-09-30 devnull 		c2 += e;
472 b2cfc4e2 2003-09-30 devnull 		break;
473 b2cfc4e2 2003-09-30 devnull 	}
474 b2cfc4e2 2003-09-30 devnull 
475 b2cfc4e2 2003-09-30 devnull 	/*
476 b2cfc4e2 2003-09-30 devnull 	 * clean up c1 c2 and c3
477 b2cfc4e2 2003-09-30 devnull 	 */
478 b2cfc4e2 2003-09-30 devnull 	if(c1 < 0)
479 b2cfc4e2 2003-09-30 devnull 		c1 = 0;
480 b2cfc4e2 2003-09-30 devnull 	if(c2 < 0)
481 b2cfc4e2 2003-09-30 devnull 		c2 = 0;
482 b2cfc4e2 2003-09-30 devnull 	if(c2 > NSIGNIF) {
483 b2cfc4e2 2003-09-30 devnull 		c3 = c2-NSIGNIF;
484 b2cfc4e2 2003-09-30 devnull 		c2 = NSIGNIF;
485 b2cfc4e2 2003-09-30 devnull 	}
486 b2cfc4e2 2003-09-30 devnull 
487 b2cfc4e2 2003-09-30 devnull 	/*
488 b2cfc4e2 2003-09-30 devnull 	 * trim trailing zeros for %g
489 b2cfc4e2 2003-09-30 devnull 	 */
490 b2cfc4e2 2003-09-30 devnull 	if(!(fl & FmtSharp)
491 b2cfc4e2 2003-09-30 devnull 	&& (chr == 'g' || chr == 'h')){
492 b2cfc4e2 2003-09-30 devnull 		if(c4 >= c3){
493 b2cfc4e2 2003-09-30 devnull 			c4 -= c3;
494 b2cfc4e2 2003-09-30 devnull 			c3 = 0;
495 b2cfc4e2 2003-09-30 devnull 		}else{
496 b2cfc4e2 2003-09-30 devnull 			c3 -= c4;
497 b2cfc4e2 2003-09-30 devnull 			c4 = 0;
498 b2cfc4e2 2003-09-30 devnull 		}
499 b2cfc4e2 2003-09-30 devnull 		while(c4 && c2 > 1 && s1[c2 - 1] == '0'){
500 b2cfc4e2 2003-09-30 devnull 			c4--;
501 b2cfc4e2 2003-09-30 devnull 			c2--;
502 b2cfc4e2 2003-09-30 devnull 		}
503 b2cfc4e2 2003-09-30 devnull 	}
504 b2cfc4e2 2003-09-30 devnull 
505 b2cfc4e2 2003-09-30 devnull 	/*
506 b2cfc4e2 2003-09-30 devnull 	 * calculate the total length
507 b2cfc4e2 2003-09-30 devnull 	 */
508 b2cfc4e2 2003-09-30 devnull 	n = c1 + c2 + c3;
509 b2cfc4e2 2003-09-30 devnull 	if(sign || (fl & (FmtSign|FmtSpace)))
510 b2cfc4e2 2003-09-30 devnull 		n++;
511 b2cfc4e2 2003-09-30 devnull 	if(c4 || (fl & FmtSharp)){
512 b2cfc4e2 2003-09-30 devnull 		n++;
513 b2cfc4e2 2003-09-30 devnull 	}
514 b2cfc4e2 2003-09-30 devnull 	if(chr == 'e' || chr == 'g'){
515 b2cfc4e2 2003-09-30 devnull 		n += 4;
516 b2cfc4e2 2003-09-30 devnull 		if(e >= 100)
517 b2cfc4e2 2003-09-30 devnull 			n++;
518 b2cfc4e2 2003-09-30 devnull 	}
519 b2cfc4e2 2003-09-30 devnull 
520 b2cfc4e2 2003-09-30 devnull 	/*
521 b2cfc4e2 2003-09-30 devnull 	 * pad to width if right justified
522 b2cfc4e2 2003-09-30 devnull 	 */
523 b2cfc4e2 2003-09-30 devnull 	if((fl & (FmtWidth|FmtLeft)) == FmtWidth && n < fmt->width){
524 b2cfc4e2 2003-09-30 devnull 		if(fl & FmtZero){
525 b2cfc4e2 2003-09-30 devnull 			c1 += fmt->width - n;
526 b2cfc4e2 2003-09-30 devnull 		}else{
527 b2cfc4e2 2003-09-30 devnull 			if(__fmtpad(fmt, fmt->width - n) < 0){
528 b2cfc4e2 2003-09-30 devnull 				return -1;
529 b2cfc4e2 2003-09-30 devnull 			}
530 b2cfc4e2 2003-09-30 devnull 		}
531 b2cfc4e2 2003-09-30 devnull 	}
532 b2cfc4e2 2003-09-30 devnull 
533 b2cfc4e2 2003-09-30 devnull 	/*
534 b2cfc4e2 2003-09-30 devnull 	 * sign
535 b2cfc4e2 2003-09-30 devnull 	 */
536 b2cfc4e2 2003-09-30 devnull 	d = 0;
537 b2cfc4e2 2003-09-30 devnull 	if(sign)
538 b2cfc4e2 2003-09-30 devnull 		d = '-';
539 b2cfc4e2 2003-09-30 devnull 	else if(fl & FmtSign)
540 b2cfc4e2 2003-09-30 devnull 		d = '+';
541 b2cfc4e2 2003-09-30 devnull 	else if(fl & FmtSpace)
542 b2cfc4e2 2003-09-30 devnull 		d = ' ';
543 b2cfc4e2 2003-09-30 devnull 	if(d && fmtrune(fmt, d) < 0){
544 b2cfc4e2 2003-09-30 devnull 		return -1;
545 b2cfc4e2 2003-09-30 devnull 	}
546 b2cfc4e2 2003-09-30 devnull 
547 b2cfc4e2 2003-09-30 devnull 	/*
548 b2cfc4e2 2003-09-30 devnull 	 * copy digits
549 b2cfc4e2 2003-09-30 devnull 	 */
550 b2cfc4e2 2003-09-30 devnull 	c4 = c1 + c2 + c3 - c4;
551 b2cfc4e2 2003-09-30 devnull 	if(c1 > 0){
552 b2cfc4e2 2003-09-30 devnull 		if(fmtzdotpad(fmt, c1, c4) < 0){
553 b2cfc4e2 2003-09-30 devnull 			return -1;
554 b2cfc4e2 2003-09-30 devnull 		}
555 b2cfc4e2 2003-09-30 devnull 		c4 -= c1;
556 b2cfc4e2 2003-09-30 devnull 	}
557 b2cfc4e2 2003-09-30 devnull 	d = 0;
558 b2cfc4e2 2003-09-30 devnull 	if(c4 >= 0 && c4 < c2){
559 b2cfc4e2 2003-09-30 devnull 		if(__fmtcpy(fmt, s1, c4, c4) < 0 || fmtrune(fmt, '.') < 0)
560 b2cfc4e2 2003-09-30 devnull 			return -1;
561 b2cfc4e2 2003-09-30 devnull 		d = c4;
562 b2cfc4e2 2003-09-30 devnull 		c2 -= c4;
563 b2cfc4e2 2003-09-30 devnull 		c4 = -1;
564 b2cfc4e2 2003-09-30 devnull 	}
565 b2cfc4e2 2003-09-30 devnull 	if(__fmtcpy(fmt, (const void*)(s1 + d), c2, c2) < 0){
566 b2cfc4e2 2003-09-30 devnull 		return -1;
567 b2cfc4e2 2003-09-30 devnull 	}
568 b2cfc4e2 2003-09-30 devnull 	c4 -= c2;
569 b2cfc4e2 2003-09-30 devnull 	if(c3 > 0){
570 b2cfc4e2 2003-09-30 devnull 		if(fmtzdotpad(fmt, c3, c4) < 0){
571 b2cfc4e2 2003-09-30 devnull 			return -1;
572 b2cfc4e2 2003-09-30 devnull 		}
573 b2cfc4e2 2003-09-30 devnull 		c4 -= c3;
574 b2cfc4e2 2003-09-30 devnull 	}
575 b2cfc4e2 2003-09-30 devnull 
576 b2cfc4e2 2003-09-30 devnull 	/*
577 b2cfc4e2 2003-09-30 devnull 	 * strip trailing '0' on g conv
578 b2cfc4e2 2003-09-30 devnull 	 */
579 b2cfc4e2 2003-09-30 devnull 	if((fl & FmtSharp) && c4 == 0 && fmtrune(fmt, '.') < 0){
580 b2cfc4e2 2003-09-30 devnull 		return -1;
581 b2cfc4e2 2003-09-30 devnull 	}
582 b2cfc4e2 2003-09-30 devnull 	if(chr == 'e' || chr == 'g') {
583 b2cfc4e2 2003-09-30 devnull 		d = 0;
584 b2cfc4e2 2003-09-30 devnull 		if(ucase)
585 b2cfc4e2 2003-09-30 devnull 			s1[d++] = 'E';
586 b2cfc4e2 2003-09-30 devnull 		else
587 b2cfc4e2 2003-09-30 devnull 			s1[d++] = 'e';
588 b2cfc4e2 2003-09-30 devnull 		c1 = e;
589 b2cfc4e2 2003-09-30 devnull 		if(c1 < 0) {
590 b2cfc4e2 2003-09-30 devnull 			s1[d++] = '-';
591 b2cfc4e2 2003-09-30 devnull 			c1 = -c1;
592 b2cfc4e2 2003-09-30 devnull 		} else
593 b2cfc4e2 2003-09-30 devnull 			s1[d++] = '+';
594 b2cfc4e2 2003-09-30 devnull 		if(c1 >= 100) {
595 b2cfc4e2 2003-09-30 devnull 			s1[d++] = c1/100 + '0';
596 b2cfc4e2 2003-09-30 devnull 			c1 = c1%100;
597 b2cfc4e2 2003-09-30 devnull 		}
598 b2cfc4e2 2003-09-30 devnull 		s1[d++] = c1/10 + '0';
599 b2cfc4e2 2003-09-30 devnull 		s1[d++] = c1%10 + '0';
600 b2cfc4e2 2003-09-30 devnull 		if(__fmtcpy(fmt, s1, d, d) < 0){
601 b2cfc4e2 2003-09-30 devnull 			return -1;
602 b2cfc4e2 2003-09-30 devnull 		}
603 b2cfc4e2 2003-09-30 devnull 	}
604 b2cfc4e2 2003-09-30 devnull 	if((fl & (FmtWidth|FmtLeft)) == (FmtWidth|FmtLeft) && n < fmt->width){
605 b2cfc4e2 2003-09-30 devnull 		if(__fmtpad(fmt, fmt->width - n) < 0){
606 b2cfc4e2 2003-09-30 devnull 			return -1;
607 b2cfc4e2 2003-09-30 devnull 		}
608 b2cfc4e2 2003-09-30 devnull 	}
609 b2cfc4e2 2003-09-30 devnull 	return 0;
610 b2cfc4e2 2003-09-30 devnull }