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 #if defined(LIBC_SCCS) && !defined(lint)
38 static char sccsid[] = "@(#)strtol.c 8.1 (Berkeley) 6/4/93";
39 #endif /* LIBC_SCCS and not lint */
40 #include <limits.h>
41 #include <ctype.h>
42 #include <errno.h>
43 #include <stdlib.h>
44 #include "xlocale_private.h"
45
46 /*
47 * Convert a string to a long integer.
48 *
49 * Assumes that the upper and lower case
50 * alphabets and digits are each contiguous.
51 */
52 long
strtol_l(const char * __restrict nptr,char ** __restrict endptr,int base,locale_t locale)53 strtol_l(const char * __restrict nptr, char ** __restrict endptr, int base,
54 locale_t locale)
55 {
56 const char *s;
57 unsigned long acc;
58 char c;
59 unsigned long cutoff;
60 int neg, any, cutlim;
61 FIX_LOCALE(locale);
62
63 /*
64 * Skip white space and pick up leading +/- sign if any.
65 * If base is 0, allow 0x for hex and 0 for octal, else
66 * assume decimal; if base is already 16, allow 0x.
67 */
68 s = nptr;
69 do {
70 c = *s++;
71 } while (isspace_l((unsigned char)c, locale));
72 if (c == '-') {
73 neg = 1;
74 c = *s++;
75 } else {
76 neg = 0;
77 if (c == '+')
78 c = *s++;
79 }
80 if ((base == 0 || base == 16) &&
81 c == '0' && (*s == 'x' || *s == 'X') &&
82 ((s[1] >= '0' && s[1] <= '9') ||
83 (s[1] >= 'A' && s[1] <= 'F') ||
84 (s[1] >= 'a' && s[1] <= 'f'))) {
85 c = s[1];
86 s += 2;
87 base = 16;
88 }
89 if ((base == 0 || base == 2) &&
90 c == '0' && (*s == 'b' || *s == 'B') &&
91 (s[1] >= '0' && s[1] <= '1')) {
92 c = s[1];
93 s += 2;
94 base = 2;
95 }
96 if (base == 0)
97 base = c == '0' ? 8 : 10;
98 acc = any = 0;
99 if (base < 2 || base > 36)
100 goto noconv;
101
102 /*
103 * Compute the cutoff value between legal numbers and illegal
104 * numbers. That is the largest legal value, divided by the
105 * base. An input number that is greater than this value, if
106 * followed by a legal input character, is too big. One that
107 * is equal to this value may be valid or not; the limit
108 * between valid and invalid numbers is then based on the last
109 * digit. For instance, if the range for longs is
110 * [-2147483648..2147483647] and the input base is 10,
111 * cutoff will be set to 214748364 and cutlim to either
112 * 7 (neg==0) or 8 (neg==1), meaning that if we have accumulated
113 * a value > 214748364, or equal but the next digit is > 7 (or 8),
114 * the number is too big, and we will return a range error.
115 *
116 * Set 'any' if any `digits' consumed; make it negative to indicate
117 * overflow.
118 */
119 cutoff = neg ? (unsigned long)-(LONG_MIN + LONG_MAX) + LONG_MAX
120 : LONG_MAX;
121 cutlim = cutoff % base;
122 cutoff /= base;
123 for ( ; ; c = *s++) {
124 if (c >= '0' && c <= '9')
125 c -= '0';
126 else if (c >= 'A' && c <= 'Z')
127 c -= 'A' - 10;
128 else if (c >= 'a' && c <= 'z')
129 c -= 'a' - 10;
130 else
131 break;
132 if (c >= base)
133 break;
134 if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim))
135 any = -1;
136 else {
137 any = 1;
138 acc *= base;
139 acc += c;
140 }
141 }
142 if (any < 0) {
143 acc = neg ? LONG_MIN : LONG_MAX;
144 errno = ERANGE;
145 } else if (!any) {
146 noconv:
147 errno = EINVAL;
148 } else if (neg)
149 acc = -acc;
150 if (endptr != NULL)
151 *endptr = (char *)(any ? s - 1 : nptr);
152 return (acc);
153 }
154 long
strtol(const char * __restrict nptr,char ** __restrict endptr,int base)155 strtol(const char * __restrict nptr, char ** __restrict endptr, int base)
156 {
157 return strtol_l(nptr, endptr, base, __get_locale());
158 }
159