strtoumax.c revision 330897 
1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
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 * 3. 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#if defined(LIBC_SCCS) && !defined(lint)
38static char sccsid[] = "from @(#)strtoul.c	8.1 (Berkeley) 6/4/93";
39#endif /* LIBC_SCCS and not lint */
40#include <sys/cdefs.h>
41__FBSDID("$FreeBSD: stable/11/lib/libc/stdlib/strtoumax.c 330897 2018-03-14 03:19:51Z eadler $");
42
43#include <ctype.h>
44#include <errno.h>
45#include <stdlib.h>
46#include <inttypes.h>
47#include "xlocale_private.h"
48
49/*
50 * Convert a string to a uintmax_t integer.
51 *
52 * Assumes that the upper and lower case
53 * alphabets and digits are each contiguous.
54 */
55uintmax_t
56strtoumax_l(const char * __restrict nptr, char ** __restrict endptr, int base,
57		locale_t locale)
58{
59	const char *s;
60	uintmax_t acc;
61	char c;
62	uintmax_t cutoff;
63	int neg, any, cutlim;
64	FIX_LOCALE(locale);
65
66	/*
67	 * See strtoimax for comments as to the logic used.
68	 */
69	s = nptr;
70	do {
71		c = *s++;
72	} while (isspace_l((unsigned char)c, locale));
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 = UINTMAX_MAX / base;
97	cutlim = UINTMAX_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 = UINTMAX_MAX;
119		errno = ERANGE;
120	} else if (!any) {
121noconv:
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}
129uintmax_t
130strtoumax(const char * __restrict nptr, char ** __restrict endptr, int base)
131{
132	return strtoumax_l(nptr, endptr, base, __get_locale());
133}
134