1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1992, 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[] = "from @(#)strtol.c    8.1 (Berkeley) 6/4/93";
39 #endif /* LIBC_SCCS and not lint */
40 // #include <sys/cdefs.h>
41 // __FBSDID("$FreeBSD$");
42 
43 #include <ctype.h>
44 #include <errno.h>
45 #include <stdlib.h>
46 #include <inttypes.h>
47 // #include "xlocale_private.h"
48 
49 /*
50  * Convert a string to an intmax_t integer.
51  *
52  * Assumes that the upper and lower case
53  * alphabets and digits are each contiguous.
54  */
55 intmax_t
strtoimax_l(const char * __restrict nptr, char ** __restrict endptr, int base)56 strtoimax_l(const char * __restrict nptr, char ** __restrict endptr, int base)
57 {
58     const char *s;
59     uintmax_t acc;
60     char c;
61     uintmax_t cutoff;
62     int neg, any, cutlim;
63     // FIX_LOCALE(locale);
64 
65     /*
66      * Skip white space and pick up leading +/- sign if any.
67      * If base is 0, allow 0x for hex and 0 for octal, else
68      * assume decimal; if base is already 16, allow 0x.
69      */
70     s = nptr;
71     do {
72         c = *s++;
73     } while (isspace((unsigned char)c));
74     if (c == '-') {
75         neg = 1;
76         c = *s++;
77     } else {
78         neg = 0;
79         if (c == '+') {
80             c = *s++;
81         }
82     }
83     if ((base == 0 || base == 16) &&
84         c == '0' && (*s == 'x' || *s == 'X') &&
85         ((s[1] >= '0' && s[1] <= '9') ||
86         (s[1] >= 'A' && s[1] <= 'F') ||
87         (s[1] >= 'a' && s[1] <= 'f'))) {
88         c = s[1];
89         s += 2;
90         base = 16;
91     }
92     if (base == 0) {
93         base = c == '0' ? 8 : 10;
94     }
95     acc = any = 0;
96     if (base < 2 || base > 36) {
97         goto noconv;
98     }
99 
100     /*
101      * Compute the cutoff value between legal numbers and illegal
102      * numbers.  That is the largest legal value, divided by the
103      * base.  An input number that is greater than this value, if
104      * followed by a legal input character, is too big.  One that
105      * is equal to this value may be valid or not; the limit
106      * between valid and invalid numbers is then based on the last
107      * digit.  For instance, if the range for intmax_t is
108      * [-9223372036854775808..9223372036854775807] and the input base
109      * is 10, cutoff will be set to 922337203685477580 and cutlim to
110      * either 7 (neg==0) or 8 (neg==1), meaning that if we have
111      * accumulated a value > 922337203685477580, or equal but the
112      * next digit is > 7 (or 8), the number is too big, and we will
113      * return a range error.
114      *
115      * Set 'any' if any `digits' consumed; make it negative to indicate
116      * overflow.
117      */
118     cutoff = neg ? (uintmax_t)-(INTMAX_MIN + INTMAX_MAX) + INTMAX_MAX
119         : INTMAX_MAX;
120     cutlim = cutoff % base;
121     cutoff /= base;
122     for (;; c = *s++) {
123         if (c >= '0' && c <= '9') {
124             c -= '0';
125         } else if (c >= 'A' && c <= 'Z') {
126             c -= 'A' - 10;
127         } else if (c >= 'a' && c <= 'z') {
128             c -= 'a' - 10;
129         } else {
130             break;
131         }
132         if (c >= base) {
133             break;
134         }
135         if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim)) {
136             any = -1;
137         } else {
138             any = 1;
139             acc *= base;
140             acc += c;
141         }
142     }
143     if (any < 0) {
144         acc = neg ? INTMAX_MIN : INTMAX_MAX;
145         errno = ERANGE;
146     } else if (!any) {
147 noconv:
148         errno = EINVAL;
149     } else if (neg) {
150         acc = -acc;
151     }
152     if (endptr != NULL) {
153         *endptr = (char *)(any ? s - 1 : nptr);
154     }
155     return (acc);
156 }
157 intmax_t
strtoimax(const char * __restrict nptr, char ** __restrict endptr, int base)158 strtoimax(const char * __restrict nptr, char ** __restrict endptr, int base)
159 {
160     return strtoimax_l(nptr, endptr, base);
161 }
162