1 /* A more useful interface to strtol.
2
3 Copyright (C) 1995-1996, 1998-2001, 2003-2007, 2009-2023 Free Software
4 Foundation, Inc.
5
6 This program is free software: you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation, either version 3 of the License, or
9 (at your option) any later version.
10
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <https://www.gnu.org/licenses/>. */
18
19 /* Written by Jim Meyering. */
20
21 #ifndef __strtol
22 # define __strtol strtol
23 # define __strtol_t long int
24 # define __xstrtol xstrtol
25 # define STRTOL_T_MINIMUM LONG_MIN
26 # define STRTOL_T_MAXIMUM LONG_MAX
27 #endif
28
29 #include <config.h>
30
31 #include "xstrtol.h"
32
33 /* Some pre-ANSI implementations (e.g. SunOS 4)
34 need stderr defined if assertion checking is enabled. */
35 #include <stdio.h>
36
37 #include <ctype.h>
38 #include <errno.h>
39 #include <limits.h>
40 #include <stdckdint.h>
41 #include <stdlib.h>
42 #include <string.h>
43
44 #if XSTRTOL_INCLUDE_INTTYPES_H
45 # include <inttypes.h>
46 #endif
47
48 #include "assure.h"
49 #include "intprops.h"
50
51 static strtol_error
52 bkm_scale (__strtol_t *x, int scale_factor)
53 {
54 __strtol_t scaled;
55 if (ckd_mul (&scaled, *x, scale_factor))
56 {
57 *x = *x < 0 ? TYPE_MINIMUM (__strtol_t) : TYPE_MAXIMUM (__strtol_t);
58 return LONGINT_OVERFLOW;
59 }
60
61 *x = scaled;
62
63 return LONGINT_OK;
64 }
65
66 static strtol_error
67 bkm_scale_by_power (__strtol_t *x, int base, int power)
68 {
69 strtol_error err = LONGINT_OK;
70 while (power--)
71 err |= bkm_scale (x, base);
72 return err;
73 }
74
75 /* FIXME: comment. */
76
77 strtol_error
78 __xstrtol (const char *s, char **ptr, int strtol_base,
79 __strtol_t *val, const char *valid_suffixes)
80 {
81 char *t_ptr;
82 char **p;
83 __strtol_t tmp;
84 strtol_error err = LONGINT_OK;
85
86 assure (0 <= strtol_base && strtol_base <= 36);
87
88 p = (ptr ? ptr : &t_ptr);
89
90 errno = 0;
91
92 if (! TYPE_SIGNED (__strtol_t))
93 {
94 const char *q = s;
95 unsigned char ch = *q;
96 while (isspace (ch))
97 ch = *++q;
98 if (ch == '-')
99 return LONGINT_INVALID;
100 }
101
102 tmp = __strtol (s, p, strtol_base);
103
104 if (*p == s)
105 {
106 /* If there is no number but there is a valid suffix, assume the
107 number is 1. The string is invalid otherwise. */
108 if (valid_suffixes && **p && strchr (valid_suffixes, **p))
109 tmp = 1;
110 else
111 return LONGINT_INVALID;
112 }
113 else if (errno != 0)
114 {
115 if (errno != ERANGE)
116 return LONGINT_INVALID;
117 err = LONGINT_OVERFLOW;
118 }
119
120 /* Let valid_suffixes == NULL mean "allow any suffix". */
121 /* FIXME: update all callers except the ones that allow suffixes
122 after the number, changing last parameter NULL to "". */
123 if (!valid_suffixes)
124 {
125 *val = tmp;
126 return err;
127 }
128
129 if (**p != '\0')
130 {
131 int base = 1024;
132 int suffixes = 1;
133 strtol_error overflow;
134
135 if (!strchr (valid_suffixes, **p))
136 {
137 *val = tmp;
138 return err | LONGINT_INVALID_SUFFIX_CHAR;
139 }
140
141 switch (**p)
142 {
143 case 'E': case 'G': case 'g': case 'k': case 'K': case 'M': case 'm':
144 case 'P': case 'Q': case 'R': case 'T': case 't': case 'Y': case 'Z':
145
146 /* The "valid suffix" '0' is a special flag meaning that
147 an optional second suffix is allowed, which can change
148 the base. A suffix "B" (e.g. "100MB") stands for a power
149 of 1000, whereas a suffix "iB" (e.g. "100MiB") stands for
150 a power of 1024. If no suffix (e.g. "100M"), assume
151 power-of-1024. */
152
153 if (strchr (valid_suffixes, '0'))
154 switch (p[0][1])
155 {
156 case 'i':
157 if (p[0][2] == 'B')
158 suffixes += 2;
159 break;
160
161 case 'B':
162 case 'D': /* 'D' is obsolescent */
163 base = 1000;
164 suffixes++;
165 break;
166 }
167 }
168
169 switch (**p)
170 {
171 case 'b':
172 overflow = bkm_scale (&tmp, 512);
173 break;
174
175 case 'B':
176 /* This obsolescent first suffix is distinct from the 'B'
177 second suffix above. E.g., 'tar -L 1000B' means change
178 the tape after writing 1000 KiB of data. */
179 overflow = bkm_scale (&tmp, 1024);
180 break;
181
182 case 'c':
183 overflow = LONGINT_OK;
184 break;
185
186 case 'E': /* exa or exbi */
187 overflow = bkm_scale_by_power (&tmp, base, 6);
188 break;
189
190 case 'G': /* giga or gibi */
191 case 'g': /* 'g' is undocumented; for compatibility only */
192 overflow = bkm_scale_by_power (&tmp, base, 3);
193 break;
194
195 case 'k': /* kilo */
196 case 'K': /* kibi */
197 overflow = bkm_scale_by_power (&tmp, base, 1);
198 break;
199
200 case 'M': /* mega or mebi */
201 case 'm': /* 'm' is undocumented; for compatibility only */
202 overflow = bkm_scale_by_power (&tmp, base, 2);
203 break;
204
205 case 'P': /* peta or pebi */
206 overflow = bkm_scale_by_power (&tmp, base, 5);
207 break;
208
209 case 'Q': /* quetta or 2**100 */
210 overflow = bkm_scale_by_power (&tmp, base, 10);
211 break;
212
213 case 'R': /* ronna or 2**90 */
214 overflow = bkm_scale_by_power (&tmp, base, 9);
215 break;
216
217 case 'T': /* tera or tebi */
218 case 't': /* 't' is undocumented; for compatibility only */
219 overflow = bkm_scale_by_power (&tmp, base, 4);
220 break;
221
222 case 'w':
223 overflow = bkm_scale (&tmp, 2);
224 break;
225
226 case 'Y': /* yotta or 2**80 */
227 overflow = bkm_scale_by_power (&tmp, base, 8);
228 break;
229
230 case 'Z': /* zetta or 2**70 */
231 overflow = bkm_scale_by_power (&tmp, base, 7);
232 break;
233
234 default:
235 *val = tmp;
236 return err | LONGINT_INVALID_SUFFIX_CHAR;
237 }
238
239 err |= overflow;
240 *p += suffixes;
241 if (**p)
242 err |= LONGINT_INVALID_SUFFIX_CHAR;
243 }
244
245 *val = tmp;
246 return err;
247 }