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. 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#include <limits.h>
35#include <ctype.h>
36#include <errno.h>
37#if 0
38#include <stdlib.h>
39#endif
40#include "ansidecl.h"
41
42#ifndef ULONG_MAX
43#define	ULONG_MAX	((unsigned long)(~0L))		/* 0xFFFFFFFF */
44#endif
45
46/*
47 * Convert a string to an unsigned long integer.
48 *
49 * Ignores `locale' stuff.  Assumes that the upper and lower case
50 * alphabets and digits are each contiguous.
51 */
52unsigned long
53strtoul(nptr, endptr, base)
54	const char *nptr;
55	char **endptr;
56	register int base;
57{
58	register const char *s = nptr;
59	register unsigned long acc;
60	register int c;
61	register unsigned long cutoff;
62	register int neg = 0, any, cutlim;
63
64	/*
65	 * See strtol for comments as to the logic used.
66	 */
67	do {
68		c = *s++;
69	} while (isspace(c));
70	if (c == '-') {
71		neg = 1;
72		c = *s++;
73	} else if (c == '+')
74		c = *s++;
75	if ((base == 0 || base == 16) &&
76	    c == '0' && (*s == 'x' || *s == 'X')) {
77		c = s[1];
78		s += 2;
79		base = 16;
80	}
81	if (base == 0)
82		base = c == '0' ? 8 : 10;
83	cutoff = (unsigned long)ULONG_MAX / (unsigned long)base;
84	cutlim = (unsigned long)ULONG_MAX % (unsigned long)base;
85	for (acc = 0, any = 0;; c = *s++) {
86		if (isdigit(c))
87			c -= '0';
88		else if (isalpha(c))
89			c -= isupper(c) ? 'A' - 10 : 'a' - 10;
90		else
91			break;
92		if (c >= base)
93			break;
94		if (any < 0 || acc > cutoff || acc == cutoff && c > cutlim)
95			any = -1;
96		else {
97			any = 1;
98			acc *= base;
99			acc += c;
100		}
101	}
102	if (any < 0) {
103		acc = ULONG_MAX;
104		errno = ERANGE;
105	} else if (neg)
106		acc = -acc;
107	if (endptr != 0)
108		*endptr = (char *) (any ? s - 1 : nptr);
109	return (acc);
110}
111