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 * $Id: strtol.c,v 12.3 2006/05/28 14:04:59 bostic Exp $
34 */
35
36#include "db_config.h"
37
38#include "db_int.h"
39
40/*
41 * Convert a string to a long integer.
42 *
43 * Assumes that the upper and lower case
44 * alphabets and digits are each contiguous.
45 *
46 * PUBLIC: #ifndef HAVE_STRTOL
47 * PUBLIC: long strtol __P((const char *, char **, int));
48 * PUBLIC: #endif
49 */
50long
51strtol(nptr, endptr, base)
52	const char * nptr;
53	char ** endptr;
54	int base;
55{
56	const char *s;
57	unsigned long acc;
58	char c;
59	unsigned long cutoff;
60	int neg, any, cutlim;
61
62	/*
63	 * Skip white space and pick up leading +/- sign if any.
64	 * If base is 0, allow 0x for hex and 0 for octal, else
65	 * assume decimal; if base is already 16, allow 0x.
66	 */
67	s = nptr;
68	do {
69		c = *s++;
70	} while (isspace((unsigned char)c));
71	if (c == '-') {
72		neg = 1;
73		c = *s++;
74	} else {
75		neg = 0;
76		if (c == '+')
77			c = *s++;
78	}
79	if ((base == 0 || base == 16) &&
80	    c == '0' && (*s == 'x' || *s == 'X')) {
81		c = s[1];
82		s += 2;
83		base = 16;
84	}
85	if (base == 0)
86		base = c == '0' ? 8 : 10;
87	acc = any = 0;
88	if (base < 2 || base > 36)
89		goto noconv;
90
91	/*
92	 * Compute the cutoff value between legal numbers and illegal
93	 * numbers.  That is the largest legal value, divided by the
94	 * base.  An input number that is greater than this value, if
95	 * followed by a legal input character, is too big.  One that
96	 * is equal to this value may be valid or not; the limit
97	 * between valid and invalid numbers is then based on the last
98	 * digit.  For instance, if the range for longs is
99	 * [-2147483648..2147483647] and the input base is 10,
100	 * cutoff will be set to 214748364 and cutlim to either
101	 * 7 (neg==0) or 8 (neg==1), meaning that if we have accumulated
102	 * a value > 214748364, or equal but the next digit is > 7 (or 8),
103	 * the number is too big, and we will return a range error.
104	 *
105	 * Set 'any' if any `digits' consumed; make it negative to indicate
106	 * overflow.
107	 */
108	cutoff = neg ? (unsigned long)-(LONG_MIN + LONG_MAX) + LONG_MAX
109	    : LONG_MAX;
110	cutlim = cutoff % base;
111	cutoff /= base;
112	for ( ; ; c = *s++) {
113		if (c >= '0' && c <= '9')
114			c -= '0';
115		else if (c >= 'A' && c <= 'Z')
116			c -= 'A' - 10;
117		else if (c >= 'a' && c <= 'z')
118			c -= 'a' - 10;
119		else
120			break;
121		if (c >= base)
122			break;
123		if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim))
124			any = -1;
125		else {
126			any = 1;
127			acc *= base;
128			acc += c;
129		}
130	}
131	if (any < 0) {
132		acc = neg ? LONG_MIN : LONG_MAX;
133		errno = ERANGE;
134	} else if (!any) {
135noconv:
136		errno = EINVAL;
137	} else if (neg)
138		acc = -(long)acc;
139	if (endptr != NULL)
140		*endptr = (char *)(any ? s - 1 : nptr);
141	return (acc);
142}
143