1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1990, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Chris Torek.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35 #include <sys/cdefs.h>
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 */
47 u_quad_t
strtouq(const char * nptr,char ** endptr,int base)48 strtouq(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 != NULL)
105 *endptr = __DECONST(char *, any ? s - 1 : nptr);
106 return (acc);
107 }
108