usr/src/common/util/strtol.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 2011 Nexenta Systems, Inc. All rights reserved.
  24  */
  25
  26 /*
  27  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
  28  * Use is subject to license terms.
  29  */
  30
  31 /*      Copyright (c) 1988 AT&T */
  32 /*        All Rights Reserved   */
  33
  34 #if     defined(_KERNEL) && !defined(_BOOT)
  35 #include <sys/errno.h>
  36 #else   /* _KERNEL && !_BOOT */
  37 #if     !defined(_BOOT) && !defined(_KMDB)
  38 #include "lint.h"
  39 #endif  /* !_BOOT && !_KMDB */
  40 #include <errno.h>
  41 #include <ctype.h>
  42 #include <limits.h>
  43 #include <stdlib.h>
  44 #endif  /* _KERNEL && !_BOOT */
  45 #include "strtolctype.h"
  46 #include <sys/types.h>
  47
  48 #if     defined(_KERNEL) && !defined(_BOOT)
  49 int
  50 ddi_strtol(const char *str, char **nptr, int base, long *result)
  51 #else   /* _KERNEL && !_BOOT */
  52 long
  53 strtol(const char *str, char **nptr, int base)
  54 #endif  /* _KERNEL && !_BOOT */
  55 {
  56         long val;
  57         int c;
  58         int xx;
  59         int neg = 0;
  60         long multmin;
  61         long limit;
  62         const char **ptr = (const char **)nptr;
  63         const unsigned char *ustr = (const unsigned char *)str;
  64
  65         if (ptr != (const char **)0)
  66                 *ptr = (char *)ustr; /* in case no number is formed */
  67         if (base < 0 || base > MBASE || base == 1) {
  68                 /* base is invalid -- should be a fatal error */
  69 #if     defined(_KERNEL) && !defined(_BOOT)
  70                 return (EINVAL);
  71 #else   /* _KERNEL && !_BOOT */
  72                 errno = EINVAL;
  73                 return (0);
  74 #endif  /* _KERNEL && !_BOOT */
  75         }
  76         if (!isalnum(c = *ustr)) {
  77                 while (isspace(c))
  78                         c = *++ustr;
  79                 switch (c) {
  80                 case '-':
  81                         neg++;
  82                         /* FALLTHROUGH */
  83                 case '+':
  84                         c = *++ustr;
  85                 }
  86         }
  87         if (base == 0)
  88                 if (c != '0')
  89                         base = 10;
  90                 else if (ustr[1] == 'x' || ustr[1] == 'X')
  91                         base = 16;
  92                 else
  93                         base = 8;
  94         /*
  95          * for any base > 10, the digits incrementally following
  96          *      9 are assumed to be "abc...z" or "ABC...Z"
  97          */
  98         if (!lisalnum(c) || (xx = DIGIT(c)) >= base) {
  99                 /* no number formed */
 100 #if     defined(_KERNEL) && !defined(_BOOT)
 101                 return (EINVAL);
 102 #else   /* _KERNEL && !_BOOT */
 103                 errno = EINVAL;
 104                 return (0);
 105 #endif  /* _KERNEL && !_BOOT */
 106         }
 107         if (base == 16 && c == '0' && (ustr[1] == 'x' || ustr[1] == 'X') &&
 108             isxdigit(ustr[2]))
 109                 c = *(ustr += 2); /* skip over leading "0x" or "0X" */
 110
 111         /* this code assumes that abs(LONG_MIN) >= abs(LONG_MAX) */
 112         if (neg)
 113                 limit = LONG_MIN;
 114         else
 115                 limit = -LONG_MAX;
 116         multmin = limit / (long)base;
 117         val = -DIGIT(c);
 118         for (c = *++ustr; lisalnum(c) && (xx = DIGIT(c)) < base; ) {
 119                 /* accumulate neg avoids surprises near LONG_MAX */
 120                 if (val < multmin)
 121                         goto overflow;
 122                 val *= base;
 123                 if (val < limit + xx)
 124                         goto overflow;
 125                 val -= xx;
 126                 c = *++ustr;
 127         }
 128         if (ptr != (const char **)0)
 129                 *ptr = (char *)ustr;
 130 #if     defined(_KERNEL) && !defined(_BOOT)
 131         *result = neg ? val : -val;
 132         return (0);
 133 #else   /* _KERNEL && !_BOOT */
 134         return (neg ? val : -val);
 135 #endif  /* _KERNEL && !_BOOT */
 136
 137 overflow:
 138         for (c = *++ustr; lisalnum(c) && (xx = DIGIT(c)) < base; (c = *++ustr))
 139                 ;
 140         if (ptr != (const char **)0)
 141                 *ptr = (char *)ustr;
 142 #if     defined(_KERNEL) && !defined(_BOOT)
 143         return (ERANGE);
 144 #else   /* _KERNEL && !_BOOT */
 145         errno = ERANGE;
 146         return (neg ? LONG_MIN : LONG_MAX);
 147 #endif  /* _KERNEL && !_BOOT */
 148 }