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      1 /*	$OpenBSD: strtoull.c,v 1.5 2005/08/08 08:05:37 espie Exp $ */
      2 /*-
      3  * Copyright (c) 1992 The Regents of the University of California.
      4  * All rights reserved.
      5  *
      6  * Redistribution and use in source and binary forms, with or without
      7  * modification, are permitted provided that the following conditions
      8  * are met:
      9  * 1. Redistributions of source code must retain the above copyright
     10  *    notice, this list of conditions and the following disclaimer.
     11  * 2. Redistributions in binary form must reproduce the above copyright
     12  *    notice, this list of conditions and the following disclaimer in the
     13  *    documentation and/or other materials provided with the distribution.
     14  * 3. Neither the name of the University nor the names of its contributors
     15  *    may be used to endorse or promote products derived from this software
     16  *    without specific prior written permission.
     17  *
     18  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     28  * SUCH DAMAGE.
     29  */
     30 
     31 /* OPENBSD ORIGINAL: lib/libc/stdlib/strtoull.c */
     32 
     33 #include "includes.h"
     34 #ifndef HAVE_STRTOULL
     35 
     36 #include <sys/types.h>
     37 
     38 #include <ctype.h>
     39 #include <errno.h>
     40 #include <limits.h>
     41 #include <stdlib.h>
     42 
     43 /*
     44  * Convert a string to an unsigned long long.
     45  *
     46  * Ignores `locale' stuff.  Assumes that the upper and lower case
     47  * alphabets and digits are each contiguous.
     48  */
     49 unsigned long long
     50 strtoull(const char *nptr, char **endptr, int base)
     51 {
     52 	const char *s;
     53 	unsigned long long acc, cutoff;
     54 	int c;
     55 	int neg, any, cutlim;
     56 
     57 	/*
     58 	 * See strtoq for comments as to the logic used.
     59 	 */
     60 	s = nptr;
     61 	do {
     62 		c = (unsigned char) *s++;
     63 	} while (isspace(c));
     64 	if (c == '-') {
     65 		neg = 1;
     66 		c = *s++;
     67 	} else {
     68 		neg = 0;
     69 		if (c == '+')
     70 			c = *s++;
     71 	}
     72 	if ((base == 0 || base == 16) &&
     73 	    c == '0' && (*s == 'x' || *s == 'X')) {
     74 		c = s[1];
     75 		s += 2;
     76 		base = 16;
     77 	}
     78 	if (base == 0)
     79 		base = c == '0' ? 8 : 10;
     80 
     81 	cutoff = ULLONG_MAX / (unsigned long long)base;
     82 	cutlim = ULLONG_MAX % (unsigned long long)base;
     83 	for (acc = 0, any = 0;; c = (unsigned char) *s++) {
     84 		if (isdigit(c))
     85 			c -= '0';
     86 		else if (isalpha(c))
     87 			c -= isupper(c) ? 'A' - 10 : 'a' - 10;
     88 		else
     89 			break;
     90 		if (c >= base)
     91 			break;
     92 		if (any < 0)
     93 			continue;
     94 		if (acc > cutoff || (acc == cutoff && c > cutlim)) {
     95 			any = -1;
     96 			acc = ULLONG_MAX;
     97 			errno = ERANGE;
     98 		} else {
     99 			any = 1;
    100 			acc *= (unsigned long long)base;
    101 			acc += c;
    102 		}
    103 	}
    104 	if (neg && any > 0)
    105 		acc = -acc;
    106 	if (endptr != 0)
    107 		*endptr = (char *) (any ? s - 1 : nptr);
    108 	return (acc);
    109 }
    110 #endif /* !HAVE_STRTOULL */
    111