gonzui

    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: #include <sys/types.h>
   32: 
   33: #include <ctype.h>
   34: #include <errno.h>
   35: #include <limits.h>
   36: #include <stdlib.h>
   37: 
   38: /*
   39:  * Convert a string to an unsigned long long.
   40:  *
   41:  * Ignores `locale' stuff.  Assumes that the upper and lower case
   42:  * alphabets and digits are each contiguous.
   43:  */
   44: unsigned long long
   45: strtoull(const char *nptr, char **endptr, int base)
   46: {
   47:         const char *s;
   48:         unsigned long long acc, cutoff;
   49:         int c;
   50:         int neg, any, cutlim;
   51: 
   52:         /*
   53:          * See strtoq for comments as to the logic used.
   54:          */
   55:         s = nptr;
   56:         do {
   57:                 c = (unsigned char) *s++;
   58:         } while (isspace(c));
   59:         if (c == '-') {
   60:                 neg = 1;
   61:                 c = *s++;
   62:         } else { 
   63:                 neg = 0;
   64:                 if (c == '+')
   65:                         c = *s++;
   66:         }
   67:         if ((base == 0 || base == 16) &&
   68:             c == '0' && (*s == 'x' || *s == 'X')) {
   69:                 c = s[1];
   70:                 s += 2;
   71:                 base = 16;
   72:         }
   73:         if (base == 0)
   74:                 base = c == '0' ? 8 : 10;
   75: 
   76:         cutoff = ULLONG_MAX / (unsigned long long)base;
   77:         cutlim = ULLONG_MAX % (unsigned long long)base;
   78:         for (acc = 0, any = 0;; c = (unsigned char) *s++) {
   79:                 if (isdigit(c))
   80:                         c -= '0';
   81:                 else if (isalpha(c))
   82:                         c -= isupper(c) ? 'A' - 10 : 'a' - 10;
   83:                 else
   84:                         break;
   85:                 if (c >= base)
   86:                         break;
   87:                 if (any < 0)
   88:                         continue;
   89:                 if (acc > cutoff || (acc == cutoff && c > cutlim)) {
   90:                         any = -1;
   91:                         acc = ULLONG_MAX;
   92:                         /*errno = ERANGE*/;
   93:                 } else {
   94:                         any = 1;
   95:                         acc *= (unsigned long long)base;
   96:                         acc += c;
   97:                 }
   98:         }
   99:         if (neg && any > 0)
  100:                 acc = -acc;
  101:         if (endptr != 0)
  102:                 *endptr = (char *) (any ? s - 1 : nptr);
  103:         return (acc);
  104: }
  105: 
  106: #ifdef __weak_alias
  107: __weak_alias(strtouq, strtoull);
  108: #else
  109: u_quad_t
  110: strtouq(const char *nptr, char **endptr, int base)
  111: {
  112: 
  113:         return ((u_quad_t)strtoull(nptr, endptr, base));
  114: }
  115: #endif