1 /*
2  * Copyright (c) 1990 Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. [rescinded 22 July 1999]
14  * 4. 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 #ifdef HAVE_CONFIG_H
32 #include "config.h"
33 #endif
34 #ifdef HAVE_LIMITS_H
35 #include <limits.h>
36 #endif
37 #ifdef HAVE_SYS_PARAM_H
38 #include <sys/param.h>
39 #endif
40 #include <errno.h>
41 #ifdef NEED_DECLARATION_ERRNO
42 extern int errno;
43 #endif
44 #if 0
45 #include <stdlib.h>
46 #endif
47 #include "ansidecl.h"
48 #include "safe-ctype.h"
49 
50 #ifndef ULONG_MAX
51 #define   ULONG_MAX ((unsigned long)(~0L))                  /* 0xFFFFFFFF */
52 #endif
53 
54 /*
55  * Convert a string to an unsigned long integer.
56  *
57  * Ignores `locale' stuff.  Assumes that the upper and lower case
58  * alphabets and digits are each contiguous.
59  */
60 unsigned long
strtoul(const char * nptr,char ** endptr,register int base)61 strtoul(const char *nptr, char **endptr, register int base)
62 {
63           register const char *s = nptr;
64           register unsigned long acc;
65           register int c;
66           register unsigned long cutoff;
67           register int neg = 0, any, cutlim;
68 
69           /*
70            * See strtol for comments as to the logic used.
71            */
72           do {
73                     c = *s++;
74           } while (ISSPACE(c));
75           if (c == '-') {
76                     neg = 1;
77                     c = *s++;
78           } else if (c == '+')
79                     c = *s++;
80           if ((base == 0 || base == 16) &&
81               c == '0' && (*s == 'x' || *s == 'X')) {
82                     c = s[1];
83                     s += 2;
84                     base = 16;
85           }
86           if (base == 0)
87                     base = c == '0' ? 8 : 10;
88           cutoff = (unsigned long)ULONG_MAX / (unsigned long)base;
89           cutlim = (unsigned long)ULONG_MAX % (unsigned long)base;
90           for (acc = 0, any = 0;; c = *s++) {
91                     if (ISDIGIT(c))
92                               c -= '0';
93                     else if (ISALPHA(c))
94                               c -= ISUPPER(c) ? 'A' - 10 : 'a' - 10;
95                     else
96                               break;
97                     if (c >= base)
98                               break;
99                     if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim))
100                               any = -1;
101                     else {
102                               any = 1;
103                               acc *= base;
104                               acc += c;
105                     }
106           }
107           if (any < 0) {
108                     acc = ULONG_MAX;
109                     errno = ERANGE;
110           } else if (neg)
111                     acc = -acc;
112           if (endptr != 0)
113                     *endptr = (char *) (any ? s - 1 : nptr);
114           return (acc);
115 }
116