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-rw-r--r--lib/strtod.c189
1 files changed, 0 insertions, 189 deletions
diff --git a/lib/strtod.c b/lib/strtod.c
deleted file mode 100644
index 7b48754e..00000000
--- a/lib/strtod.c
+++ /dev/null
@@ -1,189 +0,0 @@
1/* Copyright (C) 1991, 1992, 1997, 1999, 2003 Free Software Foundation, Inc.
2
3 This program is free software; you can redistribute it and/or modify
4 it under the terms of the GNU General Public License as published by
5 the Free Software Foundation; either version 2, or (at your option)
6 any later version.
7
8 This program is distributed in the hope that it will be useful,
9 but WITHOUT ANY WARRANTY; without even the implied warranty of
10 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 GNU General Public License for more details.
12
13 You should have received a copy of the GNU General Public License
14 along with this program; if not, write to the Free Software Foundation,
15 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
16
17#ifdef HAVE_CONFIG_H
18# include <config.h>
19#endif
20
21#include <errno.h>
22#ifndef errno
23extern int errno;
24#endif
25
26#include <ctype.h>
27
28#if defined (STDC_HEADERS) || (!defined (isascii) && !defined (HAVE_ISASCII))
29# define IN_CTYPE_DOMAIN(c) 1
30#else
31# define IN_CTYPE_DOMAIN(c) isascii(c)
32#endif
33
34#define ISSPACE(c) (IN_CTYPE_DOMAIN (c) && isspace (c))
35#define ISDIGIT(c) (IN_CTYPE_DOMAIN (c) && isdigit (c))
36#define TOLOWER(c) (IN_CTYPE_DOMAIN (c) ? tolower(c) : (c))
37
38#include <math.h>
39
40#include <float.h>
41#include <stdlib.h>
42#include <string.h>
43
44/* Convert NPTR to a double. If ENDPTR is not NULL, a pointer to the
45 character after the last one used in the number is put in *ENDPTR. */
46double
47strtod (const char *nptr, char **endptr)
48{
49 register const char *s;
50 short int sign;
51
52 /* The number so far. */
53 double num;
54
55 int got_dot; /* Found a decimal point. */
56 int got_digit; /* Seen any digits. */
57
58 /* The exponent of the number. */
59 long int exponent;
60
61 if (nptr == NULL)
62 {
63 errno = EINVAL;
64 goto noconv;
65 }
66
67 s = nptr;
68
69 /* Eat whitespace. */
70 while (ISSPACE (*s))
71 ++s;
72
73 /* Get the sign. */
74 sign = *s == '-' ? -1 : 1;
75 if (*s == '-' || *s == '+')
76 ++s;
77
78 num = 0.0;
79 got_dot = 0;
80 got_digit = 0;
81 exponent = 0;
82 for (;; ++s)
83 {
84 if (ISDIGIT (*s))
85 {
86 got_digit = 1;
87
88 /* Make sure that multiplication by 10 will not overflow. */
89 if (num > DBL_MAX * 0.1)
90 /* The value of the digit doesn't matter, since we have already
91 gotten as many digits as can be represented in a `double'.
92 This doesn't necessarily mean the result will overflow.
93 The exponent may reduce it to within range.
94
95 We just need to record that there was another
96 digit so that we can multiply by 10 later. */
97 ++exponent;
98 else
99 num = (num * 10.0) + (*s - '0');
100
101 /* Keep track of the number of digits after the decimal point.
102 If we just divided by 10 here, we would lose precision. */
103 if (got_dot)
104 --exponent;
105 }
106 else if (!got_dot && *s == '.')
107 /* Record that we have found the decimal point. */
108 got_dot = 1;
109 else
110 /* Any other character terminates the number. */
111 break;
112 }
113
114 if (!got_digit)
115 goto noconv;
116
117 if (TOLOWER (*s) == 'e')
118 {
119 /* Get the exponent specified after the `e' or `E'. */
120 int save = errno;
121 char *end;
122 long int exp;
123
124 errno = 0;
125 ++s;
126 exp = strtol (s, &end, 10);
127 if (errno == ERANGE)
128 {
129 /* The exponent overflowed a `long int'. It is probably a safe
130 assumption that an exponent that cannot be represented by
131 a `long int' exceeds the limits of a `double'. */
132 if (endptr != NULL)
133 *endptr = end;
134 if (exp < 0)
135 goto underflow;
136 else
137 goto overflow;
138 }
139 else if (end == s)
140 /* There was no exponent. Reset END to point to
141 the 'e' or 'E', so *ENDPTR will be set there. */
142 end = (char *) s - 1;
143 errno = save;
144 s = end;
145 exponent += exp;
146 }
147
148 if (endptr != NULL)
149 *endptr = (char *) s;
150
151 if (num == 0.0)
152 return 0.0;
153
154 /* Multiply NUM by 10 to the EXPONENT power,
155 checking for overflow and underflow. */
156
157 if (exponent < 0)
158 {
159 if (num < DBL_MIN * pow (10.0, (double) -exponent))
160 goto underflow;
161 }
162 else if (exponent > 0)
163 {
164 if (num > DBL_MAX * pow (10.0, (double) -exponent))
165 goto overflow;
166 }
167
168 num *= pow (10.0, (double) exponent);
169
170 return num * sign;
171
172overflow:
173 /* Return an overflow error. */
174 errno = ERANGE;
175 return HUGE_VAL * sign;
176
177underflow:
178 /* Return an underflow error. */
179 if (endptr != NULL)
180 *endptr = (char *) nptr;
181 errno = ERANGE;
182 return 0.0;
183
184noconv:
185 /* There was no number. */
186 if (endptr != NULL)
187 *endptr = (char *) nptr;
188 return 0.0;
189}