xref: /netbsd-src/common/lib/libc/stdlib/strtoull.c (revision 8b0f9554ff8762542c4defc4f70e1eb76fb508fa)
1 /*	$NetBSD: strtoull.c,v 1.1 2006/10/08 03:14:55 thorpej Exp $	*/
2 
3 /*
4  * Copyright (c) 1990, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #if !defined(_KERNEL) && !defined(_STANDALONE)
33 #include <sys/cdefs.h>
34 #if defined(LIBC_SCCS) && !defined(lint)
35 #if 0
36 static char sccsid[] = "from: @(#)strtoul.c	8.1 (Berkeley) 6/4/93";
37 #else
38 __RCSID("$NetBSD: strtoull.c,v 1.1 2006/10/08 03:14:55 thorpej Exp $");
39 #endif
40 #endif /* LIBC_SCCS and not lint */
41 
42 #include "namespace.h"
43 #include <assert.h>
44 #include <ctype.h>
45 #include <errno.h>
46 #include <limits.h>
47 #include <stdlib.h>
48 
49 #ifdef __weak_alias
50 __weak_alias(strtoull, _strtoull)
51 #endif
52 
53 #else /* !_KERNEL && !_STANDALONE */
54 #include <sys/param.h>
55 #include <lib/libkern/libkern.h>
56 #define	isspace(x) ((x) == ' ' || (x) == '\t' || (x) == '\n' || (x) == '\r')
57 #define	isdigit(x) ((x) >= '0' && (x) <= '9')
58 #define	isalpha(x) (((x) >= 'a' && (x) <= 'z') || ((x) >= 'A' && (x) <= 'Z'))
59 #define	toupper(x) ((x) & ~0x20)
60 #endif
61 
62 /*
63  * Convert a string to an unsigned long long integer.
64  *
65  * Ignores `locale' stuff.  Assumes that the upper and lower case
66  * alphabets and digits are each contiguous.
67  */
68 /* LONGLONG */
69 unsigned long long int
70 strtoull(nptr, endptr, base)
71 	const char *nptr;
72 	char **endptr;
73 	int base;
74 {
75 	const char *s;
76 	/* LONGLONG */
77 	unsigned long long int acc, cutoff;
78 	int c;
79 	int neg, any, cutlim;
80 
81 	_DIAGASSERT(nptr != NULL);
82 	/* endptr may be NULL */
83 
84 	/*
85 	 * See strtol for comments as to the logic used.
86 	 */
87 	s = nptr;
88 	do {
89 		c = (unsigned char) *s++;
90 	} while (isspace(c));
91 	if (c == '-') {
92 		neg = 1;
93 		c = *s++;
94 	} else {
95 		neg = 0;
96 		if (c == '+')
97 			c = *s++;
98 	}
99 	if ((base == 0 || base == 16) &&
100 	    c == '0' && (*s == 'x' || *s == 'X')) {
101 		c = s[1];
102 		s += 2;
103 		base = 16;
104 	}
105 	if (base == 0)
106 		base = c == '0' ? 8 : 10;
107 
108 	/* LONGLONG */
109 	cutoff = ULLONG_MAX / (unsigned long long int)base;
110 	/* LONGLONG */
111 	cutlim = (int)(ULLONG_MAX % (unsigned long long int)base);
112 	for (acc = 0, any = 0;; c = (unsigned char) *s++) {
113 		if (isdigit(c))
114 			c -= '0';
115 		else if (isalpha(c)) {
116 #if defined(_KERNEL) || defined(_STANDALONE)
117 			c = toupper(c) - 'A' + 10;
118 #else
119 			c -= isupper(c) ? 'A' - 10 : 'a' - 10;
120 #endif
121 		} else
122 			break;
123 		if (c >= base)
124 			break;
125 		if (any < 0)
126 			continue;
127 		if (acc > cutoff || (acc == cutoff && c > cutlim)) {
128 #if defined(_KERNEL) || defined(_STANDALONE)
129 			if (endptr)
130 				*endptr = __UNCONST(nptr);
131 			return (ULLONG_MAX);
132 #else
133 			any = -1;
134 			acc = ULLONG_MAX;
135 			errno = ERANGE;
136 #endif
137 		} else {
138 			any = 1;
139 			/* LONGLONG */
140 			acc *= (unsigned long long int)base;
141 			acc += c;
142 		}
143 	}
144 	if (neg && any > 0)
145 		acc = -acc;
146 	if (endptr != 0)
147 		*endptr = __UNCONST(any ? s - 1 : nptr);
148 	return (acc);
149 }
150