1 /* Copyright (c) 2005, Dmitry Xmelkov
2 All rights reserved.
3
4 Redistribution and use in source and binary forms, with or without
5 modification, are permitted provided that the following conditions are met:
6
7 * Redistributions of source code must retain the above copyright
8 notice, this list of conditions and the following disclaimer.
9 * Redistributions in binary form must reproduce the above copyright
10 notice, this list of conditions and the following disclaimer in
11 the documentation and/or other materials provided with the
12 distribution.
13 * Neither the name of the copyright holders nor the names of
14 contributors may be used to endorse or promote products derived
15 from this software without specific prior written permission.
16
17 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
18 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
21 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
22 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
23 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
24 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
25 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
26 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
27 POSSIBILITY OF SUCH DAMAGE. */
28
29 /* $Id: dtoa_prf.c 1944 2009-04-01 23:12:20Z arcanum $ */
30
31 #include "ftoa_engine.h"
32 #include "dtoa_conv.h"
33 #include "sectionname.h"
34
35 ATTRIBUTE_CLIB_SECTION
36 int
dtoa_prf(double val,char * s,unsigned char width,unsigned char prec,unsigned char flags)37 dtoa_prf (double val, char *s, unsigned char width, unsigned char prec,
38 unsigned char flags)
39 {
40 int exp;
41 int n;
42 unsigned char vtype;
43 unsigned char sign;
44 unsigned char ndigs;
45 unsigned char buf[9];
46
47 ndigs = prec < 60 ? prec + 1 : 60;
48 exp = __ftoa_engine (val, (char *)buf, 7, ndigs);
49 vtype = buf[0];
50
51 sign = 0;
52 if ((vtype & (FTOA_MINUS | FTOA_NAN)) == FTOA_MINUS)
53 sign = '-';
54 else if (flags & DTOA_PLUS)
55 sign = '+';
56 else if (flags & DTOA_SPACE)
57 sign = ' ';
58
59 if (vtype & FTOA_NAN) {
60 ndigs = sign ? 4 : 3;
61 width = (width > ndigs) ? width - ndigs : 0;
62 if (!(flags & DTOA_LEFT)) {
63 while (width) {
64 *s++ = ' ';
65 width--;
66 }
67 }
68 if (sign) *s++ = sign;
69 if (flags & DTOA_UPPER) {
70 *s++ = 'N'; *s++ = 'A'; *s++ = 'N';
71 } else {
72 *s++ = 'n'; *s++ = 'a'; *s++ = 'n';
73 }
74 while (width) {
75 *s++ = ' ';
76 width--;
77 }
78 *s = 0;
79 return DTOA_NONFINITE;
80 }
81
82 if (vtype & FTOA_INF) {
83 ndigs = sign ? 4 : 3;
84 width = (width > ndigs) ? width - ndigs : 0;
85 if (!(flags & DTOA_LEFT)) {
86 while (width) {
87 *s++ = ' ';
88 width--;
89 }
90 }
91 if (sign) *s++ = sign;
92 if (flags & DTOA_UPPER) {
93 *s++ = 'I'; *s++ = 'N'; *s++ = 'F';
94 } else {
95 *s++ = 'i'; *s++ = 'n'; *s++ = 'f';
96 }
97 while (width) {
98 *s++ = ' ';
99 width--;
100 }
101 *s = 0;
102 return DTOA_NONFINITE;
103 }
104
105 n = (sign ? 1 : 0) + (exp>0 ? exp+1 : 1) + (prec ? prec+1 : 0);
106 width = width > n ? width - n : 0;
107
108 if (!(flags & DTOA_LEFT) && !(flags & DTOA_ZFILL)) {
109 while (width) {
110 *s++ = ' ';
111 width--;
112 }
113 }
114 if (sign) *s++ = sign;
115 if (!(flags & DTOA_LEFT)) {
116 while (width) {
117 *s++ = '0';
118 width--;
119 }
120 }
121
122 ndigs += exp; /* exp is resticted approx. -40 .. +40 */
123 sign = buf[1];
124 if ((vtype & FTOA_CARRY) && sign == '1')
125 ndigs -= 1;
126 if ((signed char)ndigs < 1)
127 ndigs = 1;
128 else if (ndigs > 8)
129 ndigs = 8;
130
131 n = exp > 0 ? exp : 0;
132 do {
133 if (n == -1)
134 *s++ = '.';
135 flags = (n <= exp && n > exp - ndigs) ? buf[exp - n + 1] : '0';
136 if (--n < -prec)
137 break;
138 *s++ = flags;
139 } while (1);
140 if ( n == exp && (sign > '5' || (sign == '5' && !(vtype & FTOA_CARRY))) )
141 flags = '1';
142 *s++ = flags;
143
144 while (width) {
145 *s++ = ' ';
146 width--;
147 }
148 *s++ = 0;
149
150 return 0;
151 }
152 /*** end of file ***/
153