strtoull.c revision 73152 
1/*-
2 * Copyright (c) 1992, 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)
35static char sccsid[] = "@(#)strtouq.c	8.1 (Berkeley) 6/4/93";
36#endif /* LIBC_SCCS and not lint */
37
38#ifndef lint
39static const char rcsid[] =
40  "$FreeBSD: head/lib/libc/stdlib/strtoull.c 73152 2001-02-27 13:33:07Z obrien $";
41#endif
42
43#include <sys/types.h>
44
45#include <limits.h>
46#include <errno.h>
47#include <ctype.h>
48#include <stdlib.h>
49
50/*
51 * Convert a string to an unsigned long long integer.
52 *
53 * Ignores `locale' stuff.  Assumes that the upper and lower case
54 * alphabets and digits are each contiguous.
55 */
56unsigned long long
57strtoull(nptr, endptr, base)
58	const char *nptr;
59	char **endptr;
60	register int base;
61{
62	register const char *s = nptr;
63	register unsigned long long acc;
64	register unsigned char c;
65	register unsigned long long qbase, cutoff;
66	register int neg, any, cutlim;
67
68	/*
69	 * See strtoq for comments as to the logic used.
70	 */
71	s = nptr;
72	do {
73		c = *s++;
74	} while (isspace(c));
75	if (c == '-') {
76		neg = 1;
77		c = *s++;
78	} else {
79		neg = 0;
80		if (c == '+')
81			c = *s++;
82	}
83	if ((base == 0 || base == 16) &&
84	    c == '0' && (*s == 'x' || *s == 'X')) {
85		c = s[1];
86		s += 2;
87		base = 16;
88	}
89	if (base == 0)
90		base = c == '0' ? 8 : 10;
91	qbase = (unsigned)base;
92	cutoff = (unsigned long long)ULLONG_MAX / qbase;
93	cutlim = (unsigned long long)ULLONG_MAX % qbase;
94	for (acc = 0, any = 0;; c = *s++) {
95		if (!isascii(c))
96			break;
97		if (isdigit(c))
98			c -= '0';
99		else if (isalpha(c))
100			c -= isupper(c) ? 'A' - 10 : 'a' - 10;
101		else
102			break;
103		if (c >= base)
104			break;
105		if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim))
106			any = -1;
107		else {
108			any = 1;
109			acc *= qbase;
110			acc += c;
111		}
112	}
113	if (any < 0) {
114		acc = ULLONG_MAX;
115		errno = ERANGE;
116	} else if (neg)
117		acc = -acc;
118	if (endptr != 0)
119		*endptr = (char *)(any ? s - 1 : nptr);
120	return (acc);
121}
122