amiga-ixemul/stdlib/strtoul.c

96 lines
2.6 KiB
C

/*
* Copyright (c) 1990 Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that: (1) source distributions retain this entire copyright
* notice and comment, and (2) distributions including binaries display
* the following acknowledgement: ``This product includes software
* developed by the University of California, Berkeley and its contributors''
* in the documentation or other materials provided with the distribution
* and in all advertising materials mentioning features or use of this
* software. 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 ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)strtoul.c 5.2 (Berkeley) 5/17/90";
#endif /* LIBC_SCCS and not lint */
#define _KERNEL
#include "ixemul.h"
#include "kprintf.h"
#include <limits.h>
#include <ctype.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, int base)
{
register const char *s = nptr;
register unsigned long acc;
register int c;
register unsigned long cutoff;
register int neg = 0, any, cutlim;
usetup;
/*
* See strtol for comments as to the logic used.
*/
do {
c = *s++;
} while (isspace(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(c))
c -= '0';
else if (isalpha(c))
c -= isupper(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;
KPRINTF (("&errno = %lx, errno = %ld\n", &errno, errno));
} else if (neg)
acc = -acc;
if (endptr != 0)
*endptr = (char *) (any ? s - 1 : nptr);
return (acc);
}