xref: /netbsd-src/crypto/external/bsd/heimdal/dist/lib/roken/strtoull.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /*	$NetBSD: strtoull.c,v 1.2 2017/01/28 21:31:50 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 1992, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Copyright (c) 2011 The FreeBSD Foundation
8  * All rights reserved.
9  * Portions of this software were developed by David Chisnall
10  * under sponsorship from the FreeBSD Foundation.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #include <config.h>
38 
39 #include <string.h>
40 
41 #include <krb5/roken.h>
42 
43 /* #include <sys/cdefs.h> */
44 
45 #include <limits.h>
46 #include <errno.h>
47 #include <ctype.h>
48 #include <stdlib.h>
49 #include <stdint.h>
50 
51 /*
52  * Convert a string to an unsigned long long integer.
53  *
54  * Assumes that the upper and lower case
55  * alphabets and digits are each contiguous.
56  */
57 ROKEN_LIB_FUNCTION unsigned long long ROKEN_LIB_CALL
58 strtoull(const char * nptr, char ** endptr, int base)
59 {
60     const char *s;
61     unsigned long long acc;
62     char c;
63     unsigned long long cutoff;
64     int neg, any, cutlim;
65 
66     /*
67      * See strtoq for comments as to the logic used.
68      */
69     s = nptr;
70     do {
71 	c = *s++;
72     } while (isspace((unsigned char)c));
73     if (c == '-') {
74 	neg = 1;
75 	c = *s++;
76     } else {
77 	neg = 0;
78 	if (c == '+')
79 	    c = *s++;
80     }
81     if ((base == 0 || base == 16) &&
82         c == '0' && (*s == 'x' || *s == 'X') &&
83         ((s[1] >= '0' && s[1] <= '9') ||
84         (s[1] >= 'A' && s[1] <= 'F') ||
85         (s[1] >= 'a' && s[1] <= 'f'))) {
86 	c = s[1];
87 	s += 2;
88 	base = 16;
89     }
90     if (base == 0)
91 	base = c == '0' ? 8 : 10;
92     acc = any = 0;
93     if (base < 2 || base > 36)
94 	goto noconv;
95 
96     cutoff = ULLONG_MAX / base;
97     cutlim = ULLONG_MAX % base;
98     for ( ; ; c = *s++) {
99 	if (c >= '0' && c <= '9')
100 	    c -= '0';
101 	else if (c >= 'A' && c <= 'Z')
102 	    c -= 'A' - 10;
103 	else if (c >= 'a' && c <= 'z')
104 	    c -= 'a' - 10;
105 	else
106 	    break;
107 	if (c >= base)
108 	    break;
109 	if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim))
110 	    any = -1;
111 	else {
112 	    any = 1;
113 	    acc *= base;
114 	    acc += c;
115 	}
116     }
117     if (any < 0) {
118 	acc = ULLONG_MAX;
119 	errno = ERANGE;
120     } else if (!any) {
121 noconv:
122 	errno = EINVAL;
123     } else if (neg)
124 	acc = -acc;
125     if (endptr != NULL)
126 	*endptr = (char *)(any ? s - 1 : nptr);
127     return (acc);
128 }
129 
130