gen/libsa/strtol.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Portions Copyright (c) 1999 Apple Computer, Inc.  All Rights
   7  * Reserved.  This file contains Original Code and/or Modifications of
   8  * Original Code as defined in and that are subject to the Apple Public
   9  * Source License Version 1.1 (the "License").  You may not use this file
  10  * except in compliance with the License.  Please obtain a copy of the
  11  * License at http://www.apple.com/publicsource and read it before using
  12  * this file.
  13  *
  14  * The Original Code and all software distributed under the License are
  15  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  16  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  17  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE OR NON- INFRINGEMENT.  Please see the
  19  * License for the specific language governing rights and limitations
  20  * under the License.
  21  *
  22  * @APPLE_LICENSE_HEADER_END@
  23  */
  24 /*-
  25  * Copyright (c) 1990 The Regents of the University of California.
  26  * All rights reserved.
  27  *
  28  * Redistribution and use in source and binary forms, with or without
  29  * modification, are permitted provided that the following conditions
  30  * are met:
  31  * 1. Redistributions of source code must retain the above copyright
  32  *    notice, this list of conditions and the following disclaimer.
  33  * 2. Redistributions in binary form must reproduce the above copyright
  34  *    notice, this list of conditions and the following disclaimer in the
  35  *    documentation and/or other materials provided with the distribution.
  36  * 3. All advertising materials mentioning features or use of this software
  37  *    must display the following acknowledgement:
  38  *      This product includes software developed by the University of
  39  *      California, Berkeley and its contributors.
  40  * 4. Neither the name of the University nor the names of its contributors
  41  *    may be used to endorse or promote products derived from this software
  42  *    without specific prior written permission.
  43  *
  44  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  45  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  46  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  47  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  48  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  49  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  50  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  51  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  52  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  53  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  54  * SUCH DAMAGE.
  55  */
  56
  57 /* Modified by Curtis Galloway at NeXT June 1993,
  58  * for use in the standalone library.
  59  */
  60
  61 #if defined(LIBC_SCCS) && !defined(lint)
  62 static char sccsid[] = "@(#)strtol.c    5.4 (Berkeley) 2/23/91";
  63 #endif /* LIBC_SCCS and not lint */
  64
  65 #include <limits.h>
  66 #include <errno.h>
  67 //#include <stdlib.h>
  68 #import "libsa.h"
  69
  70 #import "ctype.h"
  71
  72
  73 /* Fudge here -- to save space, make strtol and strtoul do the same
  74  * conversion.  If you really need that extra range on strtoul, too bad.
  75  */
  76
  77 #define SIGNED          1
  78 #define UNSIGNED        0
  79
  80
  81 /*
  82  * Convert a string to a long integer.
  83  *
  84  * Ignores `locale' stuff.  Assumes that the upper and lower case
  85  * alphabets and digits are each contiguous.
  86  */
  87 static long
  88 actual_strtol(
  89     const char *nptr,
  90     char **endptr,
  91     register int base,
  92     int is_signed
  93 )
  94 {
  95         register const char *s = nptr;
  96         register unsigned long acc;
  97         register int c;
  98         register unsigned long cutoff;
  99         register int neg = 0, any, cutlim;
 100
 101         /*
 102          * Skip white space and pick up leading +/- sign if any.
 103          * If base is 0, allow 0x for hex and 0 for octal, else
 104          * assume decimal; if base is already 16, allow 0x.
 105          */
 106         do {
 107                 c = *s++;
 108         } while (isspace(c));
 109         if (is_signed && c == '-') {
 110                 neg = 1;
 111                 c = *s++;
 112         } else if (c == '+')
 113                 c = *s++;
 114         if ((base == 0 || base == 16) &&
 115             c == '0' && (*s == 'x' || *s == 'X')) {
 116                 c = s[1];
 117                 s += 2;
 118                 base = 16;
 119         }
 120         if (base == 0)
 121                 base = c == '0' ? 8 : 10;
 122
 123         /*
 124          * Compute the cutoff value between legal numbers and illegal
 125          * numbers.  That is the largest legal value, divided by the
 126          * base.  An input number that is greater than this value, if
 127          * followed by a legal input character, is too big.  One that
 128          * is equal to this value may be valid or not; the limit
 129          * between valid and invalid numbers is then based on the last
 130          * digit.  For instance, if the range for longs is
 131          * [-2147483648..2147483647] and the input base is 10,
 132          * cutoff will be set to 214748364 and cutlim to either
 133          * 7 (neg==0) or 8 (neg==1), meaning that if we have accumulated
 134          * a value > 214748364, or equal but the next digit is > 7 (or 8),
 135          * the number is too big, and we will return a range error.
 136          *
 137          * Set any if any `digits' consumed; make it negative to indicate
 138          * overflow.
 139          */
 140         cutoff = neg ? -(unsigned long)LONG_MIN : LONG_MAX;
 141         cutlim = cutoff % (unsigned long)base;
 142         cutoff /= (unsigned long)base;
 143         for (acc = 0, any = 0;; c = *s++) {
 144                 if (isdigit(c))
 145                         c -= '0';
 146                 else if (isalpha(c))
 147                         c -= isupper(c) ? 'A' - 10 : 'a' - 10;
 148                 else
 149                         break;
 150                 if (c >= base)
 151                         break;
 152                 if (any < 0 || acc > cutoff || acc == cutoff && c > cutlim)
 153                         any = -1;
 154                 else {
 155                         any = 1;
 156                         acc *= base;
 157                         acc += c;
 158                 }
 159         }
 160         if (any < 0) {
 161                 acc = neg ? LONG_MIN : LONG_MAX;
 162                 errno = ERANGE;
 163         } else if (neg)
 164                 acc = -acc;
 165         if (endptr != 0)
 166                 *endptr = any ? s - 1 : (char *)nptr;
 167         return (acc);
 168 }
 169
 170 long
 171 strtol(
 172     const char *nptr,
 173     char **endptr,
 174     register int base
 175 )
 176 {
 177     return actual_strtol(nptr, endptr, base, SIGNED);
 178 }
 179
 180 unsigned long
 181 strtoul(
 182     const char *nptr,
 183     char **endptr,
 184     register int base
 185 )
 186 {
 187     return actual_strtol(nptr, endptr, base, UNSIGNED);
 188 }
 189
 190 #if notdef
 191 /*
 192  * Convert a string to an unsigned long integer.
 193  *
 194  * Ignores `locale' stuff.  Assumes that the upper and lower case
 195  * alphabets and digits are each contiguous.
 196  */
 197 unsigned long
 198 strtoul(nptr, endptr, base)
 199         const char *nptr;
 200         char **endptr;
 201         register int base;
 202 {
 203         register const char *s = nptr;
 204         register unsigned long acc;
 205         register int c;
 206         register unsigned long cutoff;
 207         register int neg = 0, any, cutlim;
 208
 209         /*
 210          * See strtol for comments as to the logic used.
 211          */
 212         do {
 213                 c = *s++;
 214         } while (isspace(c));
 215         if (c == '-') {
 216                 neg = 1;
 217                 c = *s++;
 218         } else if (c == '+')
 219                 c = *s++;
 220         if ((base == 0 || base == 16) &&
 221             c == '0' && (*s == 'x' || *s == 'X')) {
 222                 c = s[1];
 223                 s += 2;
 224                 base = 16;
 225         }
 226         if (base == 0)
 227                 base = c == '0' ? 8 : 10;
 228         cutoff = (unsigned long)ULONG_MAX / (unsigned long)base;
 229         cutlim = (unsigned long)ULONG_MAX % (unsigned long)base;
 230         for (acc = 0, any = 0;; c = *s++) {
 231                 if (isdigit(c))
 232                         c -= '0';
 233                 else if (isalpha(c))
 234                         c -= isupper(c) ? 'A' - 10 : 'a' - 10;
 235                 else
 236                         break;
 237                 if (c >= base)
 238                         break;
 239                 if (any < 0 || acc > cutoff || acc == cutoff && c > cutlim)
 240                         any = -1;
 241                 else {
 242                         any = 1;
 243                         acc *= base;
 244                         acc += c;
 245                 }
 246         }
 247         if (any < 0) {
 248                 acc = ULONG_MAX;
 249                 errno = ERANGE;
 250         } else if (neg)
 251                 acc = -acc;
 252         if (endptr != 0)
 253                 *endptr = any ? s - 1 : (char *)nptr;
 254         return (acc);
 255 }
 256
 257 #endif notdef