zephyr/lib/libc/minimal/source/stdlib/strtoul.c
Abramo Bagnara 8521b43546 coding guidelines: comply with MISRA C:2012 Rule 21.13
MISRA C:2012 Rule 21.13 (Any value passed to a function in <ctype.h>
shall be representable as an unsigned char or be the value EOF).

Functions in <ctype.h> have undefined behavior if they are called with
any other value. Callers affected by this change are not prepared to
handle EOF anyway. The addition of these casts avoids the issue
and does not result in any performance penalty.

Signed-off-by: Abramo Bagnara <abramo.bagnara@bugseng.com>
Signed-off-by: Simon Hein <SHein@baumer.com>
2022-06-30 17:34:28 -04:00

107 lines
3.1 KiB
C

/* SPDX-License-Identifier: BSD-3-Clause */
/*
* Copyright (c) 1990 Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <limits.h>
#include <ctype.h>
#include <errno.h>
#include <stdlib.h>
/*
* Convert a string to an unsigned long integer.
*
* Ignores `locale' stuff. Assumes that the upper and lower case
* alphabets and digits are each contiguous.
*/
unsigned long strtoul(const char *nptr, char **endptr, register int base)
{
register const char *s = nptr;
register unsigned long acc;
register int c;
register unsigned long cutoff;
register int neg = 0, any, cutlim;
/*
* See strtol for comments as to the logic used.
*/
do {
c = *s++;
} while (isspace((unsigned char)c));
if (c == '-') {
neg = 1;
c = *s++;
} else if (c == '+') {
c = *s++;
}
if ((base == 0 || base == 16) &&
c == '0' && (*s == 'x' || *s == 'X')) {
c = s[1];
s += 2;
base = 16;
}
if (base == 0) {
base = c == '0' ? 8 : 10;
}
cutoff = (unsigned long)ULONG_MAX / (unsigned long)base;
cutlim = (unsigned long)ULONG_MAX % (unsigned long)base;
for (acc = 0, any = 0;; c = *s++) {
if (isdigit((unsigned char)c)) {
c -= '0';
} else if (isalpha((unsigned char)c)) {
c -= isupper((unsigned char)c) ? 'A' - 10 : 'a' - 10;
} else {
break;
}
if (c >= base) {
break;
}
if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim)) {
any = -1;
} else {
any = 1;
acc *= base;
acc += c;
}
}
if (any < 0) {
acc = ULONG_MAX;
errno = ERANGE;
} else if (neg) {
acc = -acc;
}
if (endptr != NULL) {
*endptr = (char *)(any ? s - 1 : nptr);
}
return acc;
}