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 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by the University of
16 *	California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34
35#include <limits.h>
36#include <ctype.h>
37#include <errno.h>
38#include <stdlib.h>
39
40#include <errno_private.h>
41
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		c = s[1];
79		s += 2;
80		base = 16;
81	}
82	if (base == 0)
83		base = c == '0' ? 8 : 10;
84	acc = any = 0;
85	if (base < 2 || base > 36)
86		goto noconv;
87
88	/*
89	 * Compute the cutoff value between legal numbers and illegal
90	 * numbers.  That is the largest legal value, divided by the
91	 * base.  An input number that is greater than this value, if
92	 * followed by a legal input character, is too big.  One that
93	 * is equal to this value may be valid or not; the limit
94	 * between valid and invalid numbers is then based on the last
95	 * digit.  For instance, if the range for longs is
96	 * [-2147483648..2147483647] and the input base is 10,
97	 * cutoff will be set to 214748364 and cutlim to either
98	 * 7 (neg==0) or 8 (neg==1), meaning that if we have accumulated
99	 * a value > 214748364, or equal but the next digit is > 7 (or 8),
100	 * the number is too big, and we will return a range error.
101	 *
102	 * Set 'any' if any `digits' consumed; make it negative to indicate
103	 * overflow.
104	 */
105	cutoff = neg ? (unsigned long)-(LONG_MIN + LONG_MAX) + LONG_MAX
106	    : LONG_MAX;
107	cutlim = cutoff % base;
108	cutoff /= base;
109	for ( ; ; c = *s++) {
110		if (c >= '0' && c <= '9')
111			c -= '0';
112		else if (c >= 'A' && c <= 'Z')
113			c -= 'A' - 10;
114		else if (c >= 'a' && c <= 'z')
115			c -= 'a' - 10;
116		else
117			break;
118		if (c >= base)
119			break;
120		if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim))
121			any = -1;
122		else {
123			any = 1;
124			acc *= base;
125			acc += c;
126		}
127	}
128	if (any < 0) {
129		acc = neg ? LONG_MIN : LONG_MAX;
130		__set_errno(ERANGE);
131	} else if (!any) {
132noconv:
133		__set_errno(EINVAL);
134	} else if (neg)
135		acc = -acc;
136	if (endptr != NULL)
137		*endptr = (char *)(any ? s - 1 : nptr);
138	return (acc);
139}
140
141
142long __strtol_internal(const char *number, char **_end, int base, int group);
143
144long
145__strtol_internal(const char *number, char **_end, int base, int group)
146{
147	// ToDo: group is currently not supported!
148	(void)group;
149
150	return strtol(number, _end, base);
151}
152
153