142 lines
4.4 KiB
C
142 lines
4.4 KiB
C
/*-
|
|
* Copyright (c) 1990, 1993
|
|
* The 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. All advertising materials mentioning features or use of this software
|
|
* must display the following acknowledgement:
|
|
* This product includes software developed by the University of
|
|
* California, Berkeley and its contributors.
|
|
* 4. 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.
|
|
*/
|
|
|
|
#if defined(LIBC_SCCS) && !defined(lint)
|
|
static char sccsid[] = "@(#)strtol.c 8.1 (Berkeley) 6/4/93";
|
|
#endif /* LIBC_SCCS and not lint */
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include <limits.h>
|
|
#include <ctype.h>
|
|
#include <errno.h>
|
|
#include <stdlib.h>
|
|
|
|
|
|
/*
|
|
* Convert a string to a long integer.
|
|
*
|
|
* Assumes that the upper and lower case
|
|
* alphabets and digits are each contiguous.
|
|
*/
|
|
long
|
|
strtol(const char * __restrict nptr, char ** __restrict endptr, int base)
|
|
{
|
|
const char *s;
|
|
unsigned long acc;
|
|
char c;
|
|
unsigned long cutoff;
|
|
int neg, any, cutlim;
|
|
|
|
/*
|
|
* Skip white space and pick up leading +/- sign if any.
|
|
* If base is 0, allow 0x for hex and 0 for octal, else
|
|
* assume decimal; if base is already 16, allow 0x.
|
|
*/
|
|
s = nptr;
|
|
do {
|
|
c = *s++;
|
|
} while (isspace((unsigned char)c));
|
|
if (c == '-') {
|
|
neg = 1;
|
|
c = *s++;
|
|
} else {
|
|
neg = 0;
|
|
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;
|
|
acc = any = 0;
|
|
if (base < 2 || base > 36)
|
|
goto noconv;
|
|
|
|
/*
|
|
* Compute the cutoff value between legal numbers and illegal
|
|
* numbers. That is the largest legal value, divided by the
|
|
* base. An input number that is greater than this value, if
|
|
* followed by a legal input character, is too big. One that
|
|
* is equal to this value may be valid or not; the limit
|
|
* between valid and invalid numbers is then based on the last
|
|
* digit. For instance, if the range for longs is
|
|
* [-2147483648..2147483647] and the input base is 10,
|
|
* cutoff will be set to 214748364 and cutlim to either
|
|
* 7 (neg==0) or 8 (neg==1), meaning that if we have accumulated
|
|
* a value > 214748364, or equal but the next digit is > 7 (or 8),
|
|
* the number is too big, and we will return a range error.
|
|
*
|
|
* Set 'any' if any `digits' consumed; make it negative to indicate
|
|
* overflow.
|
|
*/
|
|
cutoff = neg ? (unsigned long)-(LONG_MIN + LONG_MAX) + LONG_MAX
|
|
: LONG_MAX;
|
|
cutlim = cutoff % base;
|
|
cutoff /= base;
|
|
for ( ; ; c = *s++) {
|
|
if (c >= '0' && c <= '9')
|
|
c -= '0';
|
|
else if (c >= 'A' && c <= 'Z')
|
|
c -= 'A' - 10;
|
|
else if (c >= 'a' && c <= 'z')
|
|
c -= '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 = neg ? LONG_MIN : LONG_MAX;
|
|
errno = ERANGE;
|
|
} else if (!any) {
|
|
noconv:
|
|
errno = EINVAL;
|
|
} else if (neg)
|
|
acc = -acc;
|
|
if (endptr != NULL)
|
|
*endptr = (char *)(any ? s - 1 : nptr);
|
|
return (acc);
|
|
}
|