1/*-
2 * Copyright (c) 1990, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Chris Torek.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 4. Neither the name of the University nor the names of its contributors
17 *    may be used to endorse or promote products derived from this software
18 *    without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33#include <sys/cdefs.h>
34__FBSDID("$FreeBSD$");
35
36#include <sys/param.h>
37#include <sys/systm.h>
38#include <sys/ctype.h>
39#include <sys/limits.h>
40
41/*
42 * Convert a string to an unsigned quad integer.
43 *
44 * Ignores `locale' stuff.  Assumes that the upper and lower case
45 * alphabets and digits are each contiguous.
46 */
47u_quad_t
48strtouq(const char *nptr, char **endptr, int base)
49{
50	const char *s = nptr;
51	u_quad_t acc;
52	unsigned char c;
53	u_quad_t qbase, cutoff;
54	int neg, any, cutlim;
55
56	/*
57	 * See strtoq for comments as to the logic used.
58	 */
59	do {
60		c = *s++;
61	} while (isspace(c));
62	if (c == '-') {
63		neg = 1;
64		c = *s++;
65	} else {
66		neg = 0;
67		if (c == '+')
68			c = *s++;
69	}
70	if ((base == 0 || base == 16) &&
71	    c == '0' && (*s == 'x' || *s == 'X')) {
72		c = s[1];
73		s += 2;
74		base = 16;
75	}
76	if (base == 0)
77		base = c == '0' ? 8 : 10;
78	qbase = (unsigned)base;
79	cutoff = (u_quad_t)UQUAD_MAX / qbase;
80	cutlim = (u_quad_t)UQUAD_MAX % qbase;
81	for (acc = 0, any = 0;; c = *s++) {
82		if (!isascii(c))
83			break;
84		if (isdigit(c))
85			c -= '0';
86		else if (isalpha(c))
87			c -= isupper(c) ? 'A' - 10 : 'a' - 10;
88		else
89			break;
90		if (c >= base)
91			break;
92		if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim))
93			any = -1;
94		else {
95			any = 1;
96			acc *= qbase;
97			acc += c;
98		}
99	}
100	if (any < 0) {
101		acc = UQUAD_MAX;
102	} else if (neg)
103		acc = -acc;
104	if (endptr != 0)
105		*endptr = __DECONST(char *, any ? s - 1 : nptr);
106	return (acc);
107}
108