stdlib/FreeBSD/strtoull.c

   1 /*-
   2  * Copyright (c) 1992, 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 #if defined(LIBC_SCCS) && !defined(lint)
  35 static char sccsid[] = "@(#)strtouq.c   8.1 (Berkeley) 6/4/93";
  36 #endif /* LIBC_SCCS and not lint */
  37 #include <sys/cdefs.h>
  38 __FBSDID("$FreeBSD: src/lib/libc/stdlib/strtoull.c,v 1.18 2002/09/06 11:23:59 tjr Exp $");
  39
  40 #include <limits.h>
  41 #include <errno.h>
  42 #include <ctype.h>
  43 #include <stdlib.h>
  44
  45 /*
  46  * Convert a string to an unsigned long long integer.
  47  *
  48  * Assumes that the upper and lower case
  49  * alphabets and digits are each contiguous.
  50  */
  51 unsigned long long
  52 strtoull(const char * __restrict nptr, char ** __restrict endptr, int base)
  53 {
  54         const char *s;
  55         unsigned long long acc;
  56         char c;
  57         unsigned long long cutoff;
  58         int neg, any, cutlim;
  59
  60         /*
  61          * See strtoq for comments as to the logic used.
  62          */
  63         s = nptr;
  64         do {
  65                 c = *s++;
  66         } while (isspace((unsigned char)c));
  67         if (c == '-') {
  68                 neg = 1;
  69                 c = *s++;
  70         } else {
  71                 neg = 0;
  72                 if (c == '+')
  73                         c = *s++;
  74         }
  75         if ((base == 0 || base == 16) &&
  76             c == '0' && (*s == 'x' || *s == 'X')) {
  77                 c = s[1];
  78                 s += 2;
  79                 base = 16;
  80         }
  81         if (base == 0)
  82                 base = c == '0' ? 8 : 10;
  83         acc = any = 0;
  84         if (base < 2 || base > 36)
  85                 goto noconv;
  86
  87         cutoff = ULLONG_MAX / base;
  88         cutlim = ULLONG_MAX % base;
  89         for ( ; ; c = *s++) {
  90                 if (c >= '0' && c <= '9')
  91                         c -= '0';
  92                 else if (c >= 'A' && c <= 'Z')
  93                         c -= 'A' - 10;
  94                 else if (c >= 'a' && c <= 'z')
  95                         c -= 'a' - 10;
  96                 else
  97                         break;
  98                 if (c >= base)
  99                         break;
 100                 if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim))
 101                         any = -1;
 102                 else {
 103                         any = 1;
 104                         acc *= base;
 105                         acc += c;
 106                 }
 107         }
 108         if (any < 0) {
 109                 acc = ULLONG_MAX;
 110                 errno = ERANGE;
 111         } else if (!any) {
 112 noconv:
 113                 errno = EINVAL;
 114         } else if (neg)
 115                 acc = -acc;
 116         if (endptr != NULL)
 117                 *endptr = (char *)(any ? s - 1 : nptr);
 118         return (acc);
 119 }