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 * Copyright (c) 2011 The FreeBSD Foundation
8 *
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
38#include <limits.h>
39#include <ctype.h>
40#include <errno.h>
41#include <stdlib.h>
42
43/*
44 * Convert a string to a long integer.
45 *
46 * Assumes that the upper and lower case
47 * alphabets and digits are each contiguous.
48 */
49
50long
51strtol(const char * __restrict nptr, char ** __restrict endptr, int base)
52{
53	const char *s;
54	unsigned long acc;
55	char c;
56	unsigned long cutoff;
57	int neg, any, cutlim;
58
59	/*
60	 * Skip white space and pick up leading +/- sign if any.
61	 * If base is 0, allow 0x for hex and 0 for octal, else
62	 * assume decimal; if base is already 16, allow 0x.
63	 */
64	s = nptr;
65	do {
66		c = *s++;
67	} while (isspace((unsigned char)c));
68	if (c == '-') {
69		neg = 1;
70		c = *s++;
71	} else {
72		neg = 0;
73		if (c == '+')
74			c = *s++;
75	}
76	if ((base == 0 || base == 16) &&
77		c == '0' && (*s == 'x' || *s == 'X') &&
78		((s[1] >= '0' && s[1] <= '9') ||
79		(s[1] >= 'A' && s[1] <= 'F') ||
80		(s[1] >= 'a' && s[1] <= 'f'))) {
81		c = s[1];
82		s += 2;
83		base = 16;
84	}
85	if ((base == 0 || base == 2) &&
86		c == '0' && (*s == 'b' || *s == 'B') &&
87		(s[1] >= '0' && s[1] <= '1')) {
88		c = s[1];
89		s += 2;
90		base = 2;
91	}
92	if (base == 0)
93		base = c == '0' ? 8 : 10;
94	acc = any = 0;
95	if (base < 2 || base > 36)
96		goto noconv;
97
98	/*
99	 * Compute the cutoff value between legal numbers and illegal
100	 * numbers.  That is the largest legal value, divided by the
101	 * base.  An input number that is greater than this value, if
102	 * followed by a legal input character, is too big.  One that
103	 * is equal to this value may be valid or not; the limit
104	 * between valid and invalid numbers is then based on the last
105	 * digit.  For instance, if the range for longs is
106	 * [-2147483648..2147483647] and the input base is 10,
107	 * cutoff will be set to 214748364 and cutlim to either
108	 * 7 (neg==0) or 8 (neg==1), meaning that if we have accumulated
109	 * a value > 214748364, or equal but the next digit is > 7 (or 8),
110	 * the number is too big, and we will return a range error.
111	 *
112	 * Set 'any' if any `digits' consumed; make it negative to indicate
113	 * overflow.
114	 */
115	cutoff = neg ? (unsigned long)-(LONG_MIN + LONG_MAX) + LONG_MAX
116		: LONG_MAX;
117	cutlim = cutoff % base;
118	cutoff /= base;
119	for ( ; ; c = *s++) {
120		if (c >= '0' && c <= '9')
121			c -= '0';
122		else if (c >= 'A' && c <= 'Z')
123			c -= 'A' - 10;
124		else if (c >= 'a' && c <= 'z')
125			c -= 'a' - 10;
126		else
127			break;
128		if (c >= base)
129			break;
130		if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim))
131			any = -1;
132		else {
133			any = 1;
134			acc *= base;
135			acc += c;
136		}
137	}
138	if (any < 0) {
139		acc = neg ? LONG_MIN : LONG_MAX;
140		errno = ERANGE;
141	} else if (!any) {
142noconv:
143		errno = EINVAL;
144	} else if (neg)
145		acc = -acc;
146	if (endptr != NULL)
147		*endptr = (char *)(any ? s - 1 : nptr);
148	return (acc);
149}
150
151
152#ifdef __HAIKU__
153long __strtol_internal(const char *number, char **_end, int base, int group);
154
155long
156__strtol_internal(const char *number, char **_end, int base, int group)
157{
158	// ToDo: group is currently not supported!
159	(void)group;
160
161	return strtol(number, _end, base);
162}
163#endif
164