usr/src/common/util/strtoul.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21
  22 /*
  23  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 /*      Copyright (c) 1988 AT&T */
  28 /*        All Rights Reserved   */
  29
  30 #if     defined(_KERNEL)
  31 #include <sys/null.h>
  32 #endif  /* _KERNEL */
  33
  34 #if     defined(_KERNEL) && !defined(_BOOT)
  35 #include <sys/errno.h>
  36 #else   /* _KERNEL && !_BOOT */
  37 #if     !defined(_BOOT) && !defined(_KMDB) && !defined(_STANDALONE)
  38 #include "lint.h"
  39 #endif  /* !_BOOT && !_KMDB && !_STANDALONE */
  40 #if     defined(_STANDALONE)
  41 #include <sys/cdefs.h>
  42 #include <stand.h>
  43 #include <limits.h>
  44 #else
  45 #include <errno.h>
  46 #include <ctype.h>
  47 #include <limits.h>
  48 #include <stdlib.h>
  49 #endif  /* _STANDALONE */
  50 #endif  /* _KERNEL && !_BOOT */
  51 #include "strtolctype.h"
  52 #include <sys/types.h>
  53
  54 #if     defined(_KERNEL) && !defined(_BOOT)
  55 int
  56 ddi_strtoul(const char *str, char **nptr, int base, unsigned long *result)
  57 #else   /* _KERNEL && !_BOOT */
  58 unsigned long
  59 strtoul(const char *str, char **nptr, int base)
  60 #endif  /* _KERNEL && !_BOOT */
  61 {
  62         unsigned long val;
  63         int c;
  64         int xx;
  65         int neg = 0;
  66         unsigned long multmax;
  67         const char **ptr = (const char **)nptr;
  68         const unsigned char *ustr = (const unsigned char *)str;
  69
  70         if (ptr != NULL)
  71                 *ptr = (char *)ustr; /* in case no number is formed */
  72         if (base < 0 || base > MBASE || base == 1) {
  73                 /* base is invalid -- should be a fatal error */
  74 #if     defined(_KERNEL) && !defined(_BOOT)
  75                 return (EINVAL);
  76 #else   /* _KERNEL && !_BOOT */
  77                 errno = EINVAL;
  78                 return (0);
  79 #endif  /* _KERNEL && !_BOOT */
  80         }
  81         if (!isalnum(c = *ustr)) {
  82                 while (isspace(c))
  83                         c = *++ustr;
  84                 switch (c) {
  85                 case '-':
  86                         neg++;
  87                         /* FALLTHROUGH */
  88                 case '+':
  89                         c = *++ustr;
  90                 }
  91         }
  92         if (base == 0) {
  93                 if (c != '0')
  94                         base = 10;
  95                 else if (ustr[1] == 'x' || ustr[1] == 'X')
  96                         base = 16;
  97                 else
  98                         base = 8;
  99         }
 100         /*
 101          * for any base > 10, the digits incrementally following
 102          *      9 are assumed to be "abc...z" or "ABC...Z"
 103          */
 104         if (!lisalnum(c) || (xx = DIGIT(c)) >= base) {
 105                 /* no number formed */
 106 #if     defined(_KERNEL) && !defined(_BOOT)
 107                 return (EINVAL);
 108 #else   /* _KERNEL && !_BOOT */
 109                 return (0);
 110 #endif  /* _KERNEL && !_BOOT */
 111         }
 112         if (base == 16 && c == '0' && (ustr[1] == 'x' || ustr[1] == 'X') &&
 113             isxdigit(ustr[2]))
 114                 c = *(ustr += 2); /* skip over leading "0x" or "0X" */
 115
 116         multmax = ULONG_MAX / (unsigned long)base;
 117         val = DIGIT(c);
 118         for (c = *++ustr; lisalnum(c) && (xx = DIGIT(c)) < base; ) {
 119                 if (val > multmax)
 120                         goto overflow;
 121                 val *= base;
 122                 if (ULONG_MAX - val < (unsigned long)xx)
 123                         goto overflow;
 124                 val += xx;
 125                 c = *++ustr;
 126         }
 127         if (ptr != NULL)
 128                 *ptr = (char *)ustr;
 129 #if     defined(_KERNEL) && !defined(_BOOT)
 130         *result = neg ? -val : val;
 131         return (0);
 132 #else   /* _KERNEL && !_BOOT */
 133         return (neg ? -val : val);
 134 #endif  /* _KERNEL && !_BOOT */
 135
 136 overflow:
 137         for (c = *++ustr; lisalnum(c) && (xx = DIGIT(c)) < base; (c = *++ustr))
 138                 ;
 139         if (ptr != NULL)
 140                 *ptr = (char *)ustr;
 141 #if     defined(_KERNEL) && !defined(_BOOT)
 142         return (ERANGE);
 143 #else   /* _KERNEL && !_BOOT */
 144         errno = ERANGE;
 145         return (ULONG_MAX);
 146 #endif  /* _KERNEL && !_BOOT */
 147 }