xref: /dragonfly/contrib/grep/lib/xstrtol.c (revision 31524921)
1 /* A more useful interface to strtol.
2 
3    Copyright (C) 1995-1996, 1998-2001, 2003-2007, 2009-2015 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 <http://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 <stdlib.h>
41 #include <string.h>
42 
43 #include "assure.h"
44 #include "intprops.h"
45 
46 /* xstrtoll.c and xstrtoull.c, which include this file, require that
47    ULLONG_MAX, LLONG_MAX, LLONG_MIN are defined, but <limits.h> does not
48    define them on all platforms.  */
49 #ifndef ULLONG_MAX
50 # define ULLONG_MAX TYPE_MAXIMUM (unsigned long long)
51 #endif
52 #ifndef LLONG_MAX
53 # define LLONG_MAX TYPE_MAXIMUM (long long int)
54 #endif
55 #ifndef LLONG_MIN
56 # define LLONG_MIN TYPE_MINIMUM (long long int)
57 #endif
58 
59 static strtol_error
60 bkm_scale (__strtol_t *x, int scale_factor)
61 {
62   if (TYPE_SIGNED (__strtol_t) && *x < STRTOL_T_MINIMUM / scale_factor)
63     {
64       *x = STRTOL_T_MINIMUM;
65       return LONGINT_OVERFLOW;
66     }
67   if (STRTOL_T_MAXIMUM / scale_factor < *x)
68     {
69       *x = STRTOL_T_MAXIMUM;
70       return LONGINT_OVERFLOW;
71     }
72   *x *= scale_factor;
73   return LONGINT_OK;
74 }
75 
76 static strtol_error
77 bkm_scale_by_power (__strtol_t *x, int base, int power)
78 {
79   strtol_error err = LONGINT_OK;
80   while (power--)
81     err |= bkm_scale (x, base);
82   return err;
83 }
84 
85 /* FIXME: comment.  */
86 
87 strtol_error
88 __xstrtol (const char *s, char **ptr, int strtol_base,
89            __strtol_t *val, const char *valid_suffixes)
90 {
91   char *t_ptr;
92   char **p;
93   __strtol_t tmp;
94   strtol_error err = LONGINT_OK;
95 
96   assure (0 <= strtol_base && strtol_base <= 36);
97 
98   p = (ptr ? ptr : &t_ptr);
99 
100   errno = 0;
101 
102   if (! TYPE_SIGNED (__strtol_t))
103     {
104       const char *q = s;
105       unsigned char ch = *q;
106       while (isspace (ch))
107         ch = *++q;
108       if (ch == '-')
109         return LONGINT_INVALID;
110     }
111 
112   tmp = __strtol (s, p, strtol_base);
113 
114   if (*p == s)
115     {
116       /* If there is no number but there is a valid suffix, assume the
117          number is 1.  The string is invalid otherwise.  */
118       if (valid_suffixes && **p && strchr (valid_suffixes, **p))
119         tmp = 1;
120       else
121         return LONGINT_INVALID;
122     }
123   else if (errno != 0)
124     {
125       if (errno != ERANGE)
126         return LONGINT_INVALID;
127       err = LONGINT_OVERFLOW;
128     }
129 
130   /* Let valid_suffixes == NULL mean "allow any suffix".  */
131   /* FIXME: update all callers except the ones that allow suffixes
132      after the number, changing last parameter NULL to "".  */
133   if (!valid_suffixes)
134     {
135       *val = tmp;
136       return err;
137     }
138 
139   if (**p != '\0')
140     {
141       int base = 1024;
142       int suffixes = 1;
143       strtol_error overflow;
144 
145       if (!strchr (valid_suffixes, **p))
146         {
147           *val = tmp;
148           return err | LONGINT_INVALID_SUFFIX_CHAR;
149         }
150 
151       if (strchr (valid_suffixes, '0'))
152         {
153           /* The "valid suffix" '0' is a special flag meaning that
154              an optional second suffix is allowed, which can change
155              the base.  A suffix "B" (e.g. "100MB") stands for a power
156              of 1000, whereas a suffix "iB" (e.g. "100MiB") stands for
157              a power of 1024.  If no suffix (e.g. "100M"), assume
158              power-of-1024.  */
159 
160           switch (p[0][1])
161             {
162             case 'i':
163               if (p[0][2] == 'B')
164                 suffixes += 2;
165               break;
166 
167             case 'B':
168             case 'D': /* 'D' is obsolescent */
169               base = 1000;
170               suffixes++;
171               break;
172             }
173         }
174 
175       switch (**p)
176         {
177         case 'b':
178           overflow = bkm_scale (&tmp, 512);
179           break;
180 
181         case 'B':
182           overflow = bkm_scale (&tmp, 1024);
183           break;
184 
185         case 'c':
186           overflow = LONGINT_OK;
187           break;
188 
189         case 'E': /* exa or exbi */
190           overflow = bkm_scale_by_power (&tmp, base, 6);
191           break;
192 
193         case 'G': /* giga or gibi */
194         case 'g': /* 'g' is undocumented; for compatibility only */
195           overflow = bkm_scale_by_power (&tmp, base, 3);
196           break;
197 
198         case 'k': /* kilo */
199         case 'K': /* kibi */
200           overflow = bkm_scale_by_power (&tmp, base, 1);
201           break;
202 
203         case 'M': /* mega or mebi */
204         case 'm': /* 'm' is undocumented; for compatibility only */
205           overflow = bkm_scale_by_power (&tmp, base, 2);
206           break;
207 
208         case 'P': /* peta or pebi */
209           overflow = bkm_scale_by_power (&tmp, base, 5);
210           break;
211 
212         case 'T': /* tera or tebi */
213         case 't': /* 't' is undocumented; for compatibility only */
214           overflow = bkm_scale_by_power (&tmp, base, 4);
215           break;
216 
217         case 'w':
218           overflow = bkm_scale (&tmp, 2);
219           break;
220 
221         case 'Y': /* yotta or 2**80 */
222           overflow = bkm_scale_by_power (&tmp, base, 8);
223           break;
224 
225         case 'Z': /* zetta or 2**70 */
226           overflow = bkm_scale_by_power (&tmp, base, 7);
227           break;
228 
229         default:
230           *val = tmp;
231           return err | LONGINT_INVALID_SUFFIX_CHAR;
232         }
233 
234       err |= overflow;
235       *p += suffixes;
236       if (**p)
237         err |= LONGINT_INVALID_SUFFIX_CHAR;
238     }
239 
240   *val = tmp;
241   return err;
242 }
243