1/*-
2 * Copyright (c) 1990, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 4. Neither the name of the University nor the names of its contributors
14 *    may be used to endorse or promote products derived from this software
15 *    without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#if defined(LIBC_SCCS) && !defined(lint)
31static char sccsid[] = "@(#)strtol.c	8.1 (Berkeley) 6/4/93";
32#endif /* LIBC_SCCS and not lint */
33#include <sys/cdefs.h>
34__FBSDID("$FreeBSD: src/lib/libc/stdlib/strtol.c,v 1.20 2007/01/09 00:28:10 imp Exp $");
35
36#include "xlocale_private.h"
37
38#include <limits.h>
39#include <ctype.h>
40#include <errno.h>
41#include <stdlib.h>
42
43
44/*
45 * Convert a string to a long integer.
46 *
47 * Assumes that the upper and lower case
48 * alphabets and digits are each contiguous.
49 */
50long
51strtol_l(const char * __restrict nptr, char ** __restrict endptr, int base,
52    locale_t loc)
53{
54	const char *s;
55	unsigned long acc;
56	char c;
57	unsigned long cutoff;
58	int neg, any, cutlim;
59
60	NORMALIZE_LOCALE(loc);
61	/*
62	 * Skip white space and pick up leading +/- sign if any.
63	 * If base is 0, allow 0x for hex and 0 for octal, else
64	 * assume decimal; if base is already 16, allow 0x.
65	 */
66	s = nptr;
67	do {
68		c = *s++;
69	} while (isspace_l((unsigned char)c, loc));
70	if (c == '-') {
71		neg = 1;
72		c = *s++;
73	} else {
74		neg = 0;
75		if (c == '+')
76			c = *s++;
77	}
78	if ((base == 0 || base == 16) &&
79	    c == '0' && (*s == 'x' || *s == 'X') &&
80	    ((s[1] >= '0' && s[1] <= '9') ||
81	    (s[1] >= 'A' && s[1] <= 'F') ||
82	    (s[1] >= 'a' && s[1] <= 'f'))) {
83		c = s[1];
84		s += 2;
85		base = 16;
86	}
87	if (base == 0)
88		base = c == '0' ? 8 : 10;
89	acc = any = 0;
90	if (base < 2 || base > 36)
91		goto noconv;
92
93	/*
94	 * Compute the cutoff value between legal numbers and illegal
95	 * numbers.  That is the largest legal value, divided by the
96	 * base.  An input number that is greater than this value, if
97	 * followed by a legal input character, is too big.  One that
98	 * is equal to this value may be valid or not; the limit
99	 * between valid and invalid numbers is then based on the last
100	 * digit.  For instance, if the range for longs is
101	 * [-2147483648..2147483647] and the input base is 10,
102	 * cutoff will be set to 214748364 and cutlim to either
103	 * 7 (neg==0) or 8 (neg==1), meaning that if we have accumulated
104	 * a value > 214748364, or equal but the next digit is > 7 (or 8),
105	 * the number is too big, and we will return a range error.
106	 *
107	 * Set 'any' if any `digits' consumed; make it negative to indicate
108	 * overflow.
109	 */
110	cutoff = neg ? (unsigned long)-(LONG_MIN + LONG_MAX) + LONG_MAX
111	    : LONG_MAX;
112	cutlim = cutoff % base;
113	cutoff /= base;
114	for ( ; ; c = *s++) {
115		if (c >= '0' && c <= '9')
116			c -= '0';
117		else if (c >= 'A' && c <= 'Z')
118			c -= 'A' - 10;
119		else if (c >= 'a' && c <= 'z')
120			c -= 'a' - 10;
121		else
122			break;
123		if (c >= base)
124			break;
125		if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim))
126			any = -1;
127		else {
128			any = 1;
129			acc *= base;
130			acc += c;
131		}
132	}
133	if (any < 0) {
134		acc = neg ? LONG_MIN : LONG_MAX;
135		errno = ERANGE;
136	} else if (!any) {
137noconv:
138		errno = EINVAL;
139	} else if (neg)
140		acc = -acc;
141	if (endptr != NULL)
142		*endptr = (char *)(any ? s - 1 : nptr);
143	return (acc);
144}
145
146long
147strtol(const char * __restrict nptr, char ** __restrict endptr, int base)
148{
149	return strtol_l(nptr, endptr, base, __current_locale());
150}
151