1 /* $OpenBSD: strtoull.c,v 1.7 2014/09/13 20:10:12 schwarze Exp $ */
2 /*
3 * Copyright (c) 1992 The Regents of the University of California.
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 3. Neither the name of the University nor the names of its contributors
15 * may be used to endorse or promote products derived from this software
16 * without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 */
30
31 #include <sys/types.h>
32
33 #include <ctype.h>
34 #include <errno.h>
35 #include <limits.h>
36 #include <stdlib.h>
37
38 /*
39 * Convert a string to an unsigned long long.
40 *
41 * Ignores `locale' stuff. Assumes that the upper and lower case
42 * alphabets and digits are each contiguous.
43 */
44 unsigned long long
strtoull(const char * nptr,char ** endptr,int base)45 strtoull(const char *nptr, char **endptr, int base)
46 {
47 const char *s;
48 unsigned long long acc, cutoff;
49 int c;
50 int neg, any, cutlim;
51
52 /*
53 * See strtoll for comments as to the logic used.
54 */
55 if (base < 0 || base == 1 || base > 36) {
56 if (endptr != 0)
57 *endptr = (char *)nptr;
58 errno = EINVAL;
59 return 0;
60 }
61
62 s = nptr;
63 do {
64 c = (unsigned char) *s++;
65 } while (isspace(c));
66 if (c == '-') {
67 neg = 1;
68 c = *s++;
69 } else {
70 neg = 0;
71 if (c == '+')
72 c = *s++;
73 }
74 if ((base == 0 || base == 16) &&
75 c == '0' && (*s == 'x' || *s == 'X')) {
76 c = s[1];
77 s += 2;
78 base = 16;
79 }
80 if (base == 0)
81 base = c == '0' ? 8 : 10;
82
83 cutoff = ULLONG_MAX / (unsigned long long)base;
84 cutlim = ULLONG_MAX % (unsigned long long)base;
85 for (acc = 0, any = 0;; c = (unsigned char) *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)
95 continue;
96 if (acc > cutoff || (acc == cutoff && c > cutlim)) {
97 any = -1;
98 acc = ULLONG_MAX;
99 errno = ERANGE;
100 } else {
101 any = 1;
102 acc *= (unsigned long long)base;
103 acc += c;
104 }
105 }
106 if (neg && any > 0)
107 acc = -acc;
108 if (endptr != 0)
109 *endptr = (char *) (any ? s - 1 : nptr);
110 return (acc);
111 }
112
113 __strong_alias(strtouq, strtoull);
114