external/bsd/bind/dist/lib/isc/strtoul.c

   1 /*      $NetBSD: strtoul.c,v 1.5 2014/12/10 04:37:59 christos Exp $     */
   2
   3 /*
   4  * Copyright (C) 2004, 2005, 2007, 2014  Internet Systems Consortium, Inc. ("ISC")
   5  * Copyright (C) 2003  Internet Software Consortium.
   6  *
   7  * Permission to use, copy, modify, and/or distribute this software for any
   8  * purpose with or without fee is hereby granted, provided that the above
   9  * copyright notice and this permission notice appear in all copies.
  10  *
  11  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
  12  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
  13  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
  14  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
  15  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
  16  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  17  * PERFORMANCE OF THIS SOFTWARE.
  18  */
  19
  20 /*
  21  * Copyright (c) 1990, 1993
  22  *      The Regents of the University of California.  All rights reserved.
  23  *
  24  * Redistribution and use in source and binary forms, with or without
  25  * modification, are permitted provided that the following conditions
  26  * are met:
  27  * 1. Redistributions of source code must retain the above copyright
  28  *    notice, this list of conditions and the following disclaimer.
  29  * 2. Redistributions in binary form must reproduce the above copyright
  30  *    notice, this list of conditions and the following disclaimer in the
  31  *    documentation and/or other materials provided with the distribution.
  32  * 3. Neither the name of the University nor the names of its contributors
  33  *    may be used to endorse or promote products derived from this software
  34  *    without specific prior written permission.
  35  *
  36  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  37  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  38  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  39  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  40  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  41  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  42  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  43  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  44  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  45  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  46  * SUCH DAMAGE.
  47  */
  48
  49 /*! \file */
  50 #if defined(LIBC_SCCS) && !defined(lint)
  51 static char sccsid[] = "@(#)strtoul.c   8.1 (Berkeley) 6/4/93";
  52 #endif /* LIBC_SCCS and not lint */
  53
  54 /* Id: strtoul.c,v 1.7 2007/06/19 23:47:17 tbox Exp  */
  55
  56 #include <config.h>
  57
  58 #include <limits.h>
  59 #include <ctype.h>
  60 #include <errno.h>
  61
  62 #include <isc/stdlib.h>
  63 #include <isc/util.h>
  64
  65 /*!
  66  * Convert a string to an unsigned long integer.
  67  *
  68  * Ignores `locale' stuff.  Assumes that the upper and lower case
  69  * alphabets and digits are each contiguous.
  70  */
  71 unsigned long
  72 isc_strtoul(const char *nptr, char **endptr, int base) {
  73         const char *s = nptr;
  74         unsigned long acc;
  75         unsigned char c;
  76         unsigned long cutoff;
  77         int neg = 0, any, cutlim;
  78
  79         /*
  80          * See strtol for comments as to the logic used.
  81          */
  82         do {
  83                 c = *s++;
  84         } while (isspace(c));
  85         if (c == '-') {
  86                 neg = 1;
  87                 c = *s++;
  88         } else if (c == '+')
  89                 c = *s++;
  90         if ((base == 0 || base == 16) &&
  91             c == '0' && (*s == 'x' || *s == 'X')) {
  92                 c = s[1];
  93                 s += 2;
  94                 base = 16;
  95         }
  96         if (base == 0)
  97                 base = c == '0' ? 8 : 10;
  98         cutoff = (unsigned long)ULONG_MAX / (unsigned long)base;
  99         cutlim = (unsigned long)ULONG_MAX % (unsigned long)base;
 100         for (acc = 0, any = 0;; c = *s++) {
 101                 if (!isascii(c))
 102                         break;
 103                 if (isdigit(c))
 104                         c -= '0';
 105                 else if (isalpha(c))
 106                         c -= isupper(c) ? 'A' - 10 : 'a' - 10;
 107                 else
 108                         break;
 109                 if (c >= base)
 110                         break;
 111                 if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim))
 112                         any = -1;
 113                 else {
 114                         any = 1;
 115                         acc *= base;
 116                         acc += c;
 117                 }
 118         }
 119         if (any < 0) {
 120                 acc = ULONG_MAX;
 121                 errno = ERANGE;
 122         } else if (neg)
 123                 acc = -acc;
 124         if (endptr != 0)
 125                 DE_CONST(any ? s - 1 : nptr, *endptr);
 126         return (acc);
 127 }