vx32

Local 9vx git repository for patches.
git clone git://r-36.net/vx32
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strtoul.c (3402B)


      1 /*
      2  * Copyright (c) 1990, 1993
      3  *	The Regents of the University of California.  All rights reserved.
      4  *
      5  * Redistribution and use in source and binary forms, with or without
      6  * modification, are permitted provided that the following conditions
      7  * are met:
      8  * 1. Redistributions of source code must retain the above copyright
      9  *    notice, this list of conditions and the following disclaimer.
     10  * 2. Redistributions in binary form must reproduce the above copyright
     11  *    notice, this list of conditions and the following disclaimer in the
     12  *    documentation and/or other materials provided with the distribution.
     13  * 3. All advertising materials mentioning features or use of this software
     14  *    must display the following acknowledgement:
     15  *	This product includes software developed by the University of
     16  *	California, Berkeley and its contributors.
     17  * 4. Neither the name of the University nor the names of its contributors
     18  *    may be used to endorse or promote products derived from this software
     19  *    without specific prior written permission.
     20  *
     21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     31  * SUCH DAMAGE.
     32  */
     33 
     34 #include <limits.h>
     35 #include <ctype.h>
     36 #include <errno.h>
     37 #include <stdlib.h>
     38 
     39 /*
     40  * Convert a string to an unsigned long integer.
     41  *
     42  * Assumes that the upper and lower case
     43  * alphabets and digits are each contiguous.
     44  */
     45 unsigned long
     46 strtoul(const char * __restrict nptr, char ** __restrict endptr, int base)
     47 {
     48 	const char *s;
     49 	unsigned long acc;
     50 	char c;
     51 	unsigned long cutoff;
     52 	int neg, any, cutlim;
     53 
     54 	/*
     55 	 * See strtol for comments as to the logic used.
     56 	 */
     57 	s = nptr;
     58 	do {
     59 		c = *s++;
     60 	} while (isspace((unsigned char)c));
     61 	if (c == '-') {
     62 		neg = 1;
     63 		c = *s++;
     64 	} else {
     65 		neg = 0;
     66 		if (c == '+')
     67 			c = *s++;
     68 	}
     69 	if ((base == 0 || base == 16) &&
     70 	    c == '0' && (*s == 'x' || *s == 'X') &&
     71 	    ((s[1] >= '0' && s[1] <= '9') ||
     72 	    (s[1] >= 'A' && s[1] <= 'F') ||
     73 	    (s[1] >= 'a' && s[1] <= 'f'))) {
     74 		c = s[1];
     75 		s += 2;
     76 		base = 16;
     77 	}
     78 	if (base == 0)
     79 		base = c == '0' ? 8 : 10;
     80 	acc = any = 0;
     81 	if (base < 2 || base > 36)
     82 		goto noconv;
     83 
     84 	cutoff = ULONG_MAX / base;
     85 	cutlim = ULONG_MAX % base;
     86 	for ( ; ; c = *s++) {
     87 		if (c >= '0' && c <= '9')
     88 			c -= '0';
     89 		else if (c >= 'A' && c <= 'Z')
     90 			c -= 'A' - 10;
     91 		else if (c >= 'a' && c <= 'z')
     92 			c -= 'a' - 10;
     93 		else
     94 			break;
     95 		if (c >= base)
     96 			break;
     97 		if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim))
     98 			any = -1;
     99 		else {
    100 			any = 1;
    101 			acc *= base;
    102 			acc += c;
    103 		}
    104 	}
    105 	if (any < 0) {
    106 		acc = ULONG_MAX;
    107 		errno = ERANGE;
    108 	} else if (!any) {
    109 noconv:
    110 		errno = EINVAL;
    111 	} else if (neg)
    112 		acc = -acc;
    113 	if (endptr != NULL)
    114 		*endptr = (char *)(any ? s - 1 : nptr);
    115 	return (acc);
    116 }