Subversion Repositories shark

Rev

Go to most recent revision | Details | Last modification | View Log | RSS feed

Rev Author Line No. Line
2 pj 1
/*
2
 * Copyright (c) 1990, 1993
3
 *      The Regents of the University of California.  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. All advertising materials mentioning features or use of this software
14
 *    must display the following acknowledgement:
15
 *      This product includes software developed by the University of
16
 *      California, Berkeley and its contributors.
17
 * 4. Neither the name of the University nor the names of its contributors
18
 *    may be used to endorse or promote products derived from this software
19
 *    without specific prior written permission.
20
 *
21
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31
 * SUCH DAMAGE.
32
 */
33
 
34
#if defined(LIBC_SCCS) && !defined(lint)
35
static char sccsid[] = "@(#)strtoul.c   8.1 (Berkeley) 6/4/93";
36
#endif /* LIBC_SCCS and not lint */
37
 
38
#include <limits.h>
39
#include <ctype.h>
40
#include <errno.h>
41
#include <stdlib.h>
42
 
43
/*
44
 * Convert a string to an unsigned long integer.
45
 *
46
 * Ignores `locale' stuff.  Assumes that the upper and lower case
47
 * alphabets and digits are each contiguous.
48
 */
49
unsigned long
50
strtoul(nptr, endptr, base)
51
        const char *nptr;
52
        char **endptr;
53
        register int base;
54
{
55
        register const char *s = nptr;
56
        register unsigned long acc;
57
        register unsigned char c;
58
        register unsigned long cutoff;
59
        register int neg = 0, any, cutlim;
60
 
61
        /*
62
         * See strtol for comments as to the logic used.
63
         */
64
        do {
65
                c = *s++;
66
        } while (isspace(c));
67
        if (c == '-') {
68
                neg = 1;
69
                c = *s++;
70
        } else if (c == '+')
71
                c = *s++;
72
        if ((base == 0 || base == 16) &&
73
            c == '0' && (*s == 'x' || *s == 'X')) {
74
                c = s[1];
75
                s += 2;
76
                base = 16;
77
        }
78
        if (base == 0)
79
                base = c == '0' ? 8 : 10;
80
        cutoff = (unsigned long)ULONG_MAX / (unsigned long)base;
81
        cutlim = (unsigned long)ULONG_MAX % (unsigned long)base;
82
        for (acc = 0, any = 0;; c = *s++) {
83
                if (!isascii(c))
84
                        break;
85
                if (isdigit(c))
86
                        c -= '0';
87
                else if (isalpha(c))
88
                        c -= isupper(c) ? 'A' - 10 : 'a' - 10;
89
                else
90
                        break;
91
                if (c >= base)
92
                        break;
93
                if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim))
94
                        any = -1;
95
                else {
96
                        any = 1;
97
                        acc *= base;
98
                        acc += c;
99
                }
100
        }
101
        if (any < 0) {
102
                acc = ULONG_MAX;
103
                errno = ERANGE;
104
        } else if (neg)
105
                acc = -acc;
106
        if (endptr != 0)
107
                *endptr = (char *)(any ? s - 1 : nptr);
108
        return (acc);
109
}