1 |
|
|
/* $OpenBSD: strtoul.c,v 1.11 2017/07/06 16:23:11 millert Exp $ */ |
2 |
|
|
/* |
3 |
|
|
* Copyright (c) 1990 The Regents of the University of California. |
4 |
|
|
* All rights reserved. |
5 |
|
|
* |
6 |
|
|
* Redistribution and use in source and binary forms, with or without |
7 |
|
|
* modification, are permitted provided that the following conditions |
8 |
|
|
* are met: |
9 |
|
|
* 1. Redistributions of source code must retain the above copyright |
10 |
|
|
* notice, this list of conditions and the following disclaimer. |
11 |
|
|
* 2. Redistributions in binary form must reproduce the above copyright |
12 |
|
|
* notice, this list of conditions and the following disclaimer in the |
13 |
|
|
* documentation and/or other materials provided with the distribution. |
14 |
|
|
* 3. Neither the name of the University nor the names of its contributors |
15 |
|
|
* may be used to endorse or promote products derived from this software |
16 |
|
|
* without specific prior written permission. |
17 |
|
|
* |
18 |
|
|
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
19 |
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
20 |
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
21 |
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
22 |
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
23 |
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
24 |
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
25 |
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
26 |
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
27 |
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
28 |
|
|
* SUCH DAMAGE. |
29 |
|
|
*/ |
30 |
|
|
|
31 |
|
|
#include <ctype.h> |
32 |
|
|
#include <errno.h> |
33 |
|
|
#include <limits.h> |
34 |
|
|
#include <stdlib.h> |
35 |
|
|
|
36 |
|
|
/* |
37 |
|
|
* Convert a string to an unsigned long integer. |
38 |
|
|
* |
39 |
|
|
* Ignores `locale' stuff. Assumes that the upper and lower case |
40 |
|
|
* alphabets and digits are each contiguous. |
41 |
|
|
*/ |
42 |
|
|
unsigned long |
43 |
|
|
strtoul(const char *nptr, char **endptr, int base) |
44 |
|
|
{ |
45 |
|
|
const char *s; |
46 |
|
|
unsigned long acc, cutoff; |
47 |
|
|
int c; |
48 |
|
|
int neg, any, cutlim; |
49 |
|
|
|
50 |
|
|
/* |
51 |
|
|
* See strtol for comments as to the logic used. |
52 |
|
|
*/ |
53 |
|
|
if (base < 0 || base == 1 || base > 36) { |
54 |
|
|
if (endptr != 0) |
55 |
|
|
*endptr = (char *)nptr; |
56 |
|
|
errno = EINVAL; |
57 |
|
|
return 0; |
58 |
|
|
} |
59 |
|
|
|
60 |
|
|
s = nptr; |
61 |
|
|
do { |
62 |
|
|
c = (unsigned char) *s++; |
63 |
|
|
} while (isspace(c)); |
64 |
|
|
if (c == '-') { |
65 |
|
|
neg = 1; |
66 |
|
|
c = *s++; |
67 |
|
|
} else { |
68 |
|
|
neg = 0; |
69 |
|
|
if (c == '+') |
70 |
|
|
c = *s++; |
71 |
|
|
} |
72 |
|
|
if ((base == 0 || base == 16) && c == '0' && |
73 |
|
|
(*s == 'x' || *s == 'X') && isxdigit((unsigned char)s[1])) { |
74 |
|
|
c = s[1]; |
75 |
|
|
s += 2; |
76 |
|
|
base = 16; |
77 |
|
|
} |
78 |
|
|
if (base == 0) |
79 |
|
|
base = c == '0' ? 8 : 10; |
80 |
|
|
|
81 |
|
|
cutoff = ULONG_MAX / (unsigned long)base; |
82 |
|
|
cutlim = ULONG_MAX % (unsigned long)base; |
83 |
|
|
for (acc = 0, any = 0;; c = (unsigned char) *s++) { |
84 |
|
|
if (isdigit(c)) |
85 |
|
|
c -= '0'; |
86 |
|
|
else if (isalpha(c)) |
87 |
|
|
c -= isupper(c) ? 'A' - 10 : 'a' - 10; |
88 |
|
|
else |
89 |
|
|
break; |
90 |
|
|
if (c >= base) |
91 |
|
|
break; |
92 |
|
|
if (any < 0) |
93 |
|
|
continue; |
94 |
|
|
if (acc > cutoff || (acc == cutoff && c > cutlim)) { |
95 |
|
|
any = -1; |
96 |
|
|
acc = ULONG_MAX; |
97 |
|
|
errno = ERANGE; |
98 |
|
|
} else { |
99 |
|
|
any = 1; |
100 |
|
|
acc *= (unsigned long)base; |
101 |
|
|
acc += c; |
102 |
|
|
} |
103 |
|
|
} |
104 |
|
|
if (neg && any > 0) |
105 |
|
|
acc = -acc; |
106 |
|
|
if (endptr != 0) |
107 |
|
|
*endptr = (char *) (any ? s - 1 : nptr); |
108 |
|
|
return (acc); |
109 |
|
|
} |
110 |
|
|
DEF_STRONG(strtoul); |