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 [rescinded 22 July 1999]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