contrib/sendmail-8.14/libsm/strto.c

   1 /*
   2  * Copyright (c) 2000-2001 Sendmail, Inc. and its suppliers.
   3  *      All rights reserved.
   4  * Copyright (c) 1992
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * By using this file, you agree to the terms and conditions set
   8  * forth in the LICENSE file which can be found at the top level of
   9  * the sendmail distribution.
  10  */
  11
  12 #include <sm/gen.h>
  13 SM_IDSTR(id, "@(#)$Id: strto.c,v 1.18 2001/12/30 04:59:37 gshapiro Exp $")
  14
  15 #include <sys/param.h>
  16 #include <sys/types.h>
  17 #include <stdlib.h>
  18 #include <ctype.h>
  19 #include <errno.h>
  20 #include <sm/limits.h>
  21 #include <sm/conf.h>
  22 #include <sm/string.h>
  23
  24 /*
  25 **  SM_STRTOLL --  Convert a string to a (signed) long long integer.
  26 **
  27 **  Ignores `locale' stuff.  Assumes that the upper and lower case
  28 **  alphabets and digits are each contiguous.
  29 **
  30 **      Parameters:
  31 **              nptr -- string containing number
  32 **              endptr -- location of first invalid character
  33 **              base -- numeric base that 'nptr' number is based in
  34 **
  35 **      Returns:
  36 **              Failure: on underflow LLONG_MIN is returned; on overflow
  37 **                      LLONG_MAX is returned and errno is set.
  38 **                      When 'endptr' == '\0' then the entire string 'nptr'
  39 **                      was valid.
  40 **              Success: returns the converted number
  41 */
  42
  43 LONGLONG_T
  44 sm_strtoll(nptr, endptr, base)
  45         const char *nptr;
  46         char **endptr;
  47         register int base;
  48 {
  49         register bool neg;
  50         register const char *s;
  51         register LONGLONG_T acc, cutoff;
  52         register int c;
  53         register int any, cutlim;
  54
  55         /*
  56         **  Skip white space and pick up leading +/- sign if any.
  57         **  If base is 0, allow 0x for hex and 0 for octal, else
  58         **  assume decimal; if base is already 16, allow 0x.
  59         */
  60
  61         s = nptr;
  62         do
  63         {
  64                 c = (unsigned char) *s++;
  65         } while (isascii(c) && isspace(c));
  66         if (c == '-')
  67         {
  68                 neg = true;
  69                 c = *s++;
  70         }
  71         else
  72         {
  73                 neg = false;
  74                 if (c == '+')
  75                         c = *s++;
  76         }
  77         if ((base == 0 || base == 16) &&
  78             c == '0' && (*s == 'x' || *s == 'X'))
  79         {
  80                 c = s[1];
  81                 s += 2;
  82                 base = 16;
  83         }
  84         if (base == 0)
  85                 base = c == '0' ? 8 : 10;
  86
  87         /*
  88         **  Compute the cutoff value between legal numbers and illegal
  89         **  numbers.  That is the largest legal value, divided by the
  90         **  base.  An input number that is greater than this value, if
  91         **  followed by a legal input character, is too big.  One that
  92         **  is equal to this value may be valid or not; the limit
  93         **  between valid and invalid numbers is then based on the last
  94         **  digit.  For instance, if the range for long-long's is
  95         **  [-9223372036854775808..9223372036854775807] and the input base
  96         **  is 10, cutoff will be set to 922337203685477580 and cutlim to
  97         **  either 7 (!neg) or 8 (neg), meaning that if we have
  98         **  accumulated a value > 922337203685477580, or equal but the
  99         **  next digit is > 7 (or 8), the number is too big, and we will
 100         **  return a range error.
 101         **
 102         **  Set any if any `digits' consumed; make it negative to indicate
 103         **  overflow.
 104         */
 105
 106         cutoff = neg ? LLONG_MIN : LLONG_MAX;
 107         cutlim = cutoff % base;
 108         cutoff /= base;
 109         if (neg)
 110         {
 111                 if (cutlim > 0)
 112                 {
 113                         cutlim -= base;
 114                         cutoff += 1;
 115                 }
 116                 cutlim = -cutlim;
 117         }
 118         for (acc = 0, any = 0;; c = (unsigned char) *s++)
 119         {
 120                 if (isascii(c) && isdigit(c))
 121                         c -= '0';
 122                 else if (isascii(c) && isalpha(c))
 123                         c -= isupper(c) ? 'A' - 10 : 'a' - 10;
 124                 else
 125                         break;
 126                 if (c >= base)
 127                         break;
 128                 if (any < 0)
 129                         continue;
 130                 if (neg)
 131                 {
 132                         if (acc < cutoff || (acc == cutoff && c > cutlim))
 133                         {
 134                                 any = -1;
 135                                 acc = LLONG_MIN;
 136                                 errno = ERANGE;
 137                         }
 138                         else
 139                         {
 140                                 any = 1;
 141                                 acc *= base;
 142                                 acc -= c;
 143                         }
 144                 }
 145                 else
 146                 {
 147                         if (acc > cutoff || (acc == cutoff && c > cutlim))
 148                         {
 149                                 any = -1;
 150                                 acc = LLONG_MAX;
 151                                 errno = ERANGE;
 152                         }
 153                         else
 154                         {
 155                                 any = 1;
 156                                 acc *= base;
 157                                 acc += c;
 158                         }
 159                 }
 160         }
 161         if (endptr != 0)
 162                 *endptr = (char *) (any ? s - 1 : nptr);
 163         return acc;
 164 }
 165
 166 /*
 167 **  SM_STRTOULL --  Convert a string to an unsigned long long integer.
 168 **
 169 **  Ignores `locale' stuff.  Assumes that the upper and lower case
 170 **  alphabets and digits are each contiguous.
 171 **
 172 **      Parameters:
 173 **              nptr -- string containing (unsigned) number
 174 **              endptr -- location of first invalid character
 175 **              base -- numeric base that 'nptr' number is based in
 176 **
 177 **      Returns:
 178 **              Failure: on overflow ULLONG_MAX is returned and errno is set.
 179 **                      When 'endptr' == '\0' then the entire string 'nptr'
 180 **                      was valid.
 181 **              Success: returns the converted number
 182 */
 183
 184 ULONGLONG_T
 185 sm_strtoull(nptr, endptr, base)
 186         const char *nptr;
 187         char **endptr;
 188         register int base;
 189 {
 190         register const char *s;
 191         register ULONGLONG_T acc, cutoff;
 192         register int c;
 193         register bool neg;
 194         register int any, cutlim;
 195
 196         /* See sm_strtoll for comments as to the logic used. */
 197         s = nptr;
 198         do
 199         {
 200                 c = (unsigned char) *s++;
 201         } while (isascii(c) && isspace(c));
 202         neg = (c == '-');
 203         if (neg)
 204         {
 205                 c = *s++;
 206         }
 207         else
 208         {
 209                 if (c == '+')
 210                         c = *s++;
 211         }
 212         if ((base == 0 || base == 16) &&
 213             c == '0' && (*s == 'x' || *s == 'X'))
 214         {
 215                 c = s[1];
 216                 s += 2;
 217                 base = 16;
 218         }
 219         if (base == 0)
 220                 base = c == '0' ? 8 : 10;
 221
 222         cutoff = ULLONG_MAX / (ULONGLONG_T)base;
 223         cutlim = ULLONG_MAX % (ULONGLONG_T)base;
 224         for (acc = 0, any = 0;; c = (unsigned char) *s++)
 225         {
 226                 if (isascii(c) && isdigit(c))
 227                         c -= '0';
 228                 else if (isascii(c) && isalpha(c))
 229                         c -= isupper(c) ? 'A' - 10 : 'a' - 10;
 230                 else
 231                         break;
 232                 if (c >= base)
 233                         break;
 234                 if (any < 0)
 235                         continue;
 236                 if (acc > cutoff || (acc == cutoff && c > cutlim))
 237                 {
 238                         any = -1;
 239                         acc = ULLONG_MAX;
 240                         errno = ERANGE;
 241                 }
 242                 else
 243                 {
 244                         any = 1;
 245                         acc *= (ULONGLONG_T)base;
 246                         acc += c;
 247                 }
 248         }
 249         if (neg && any > 0)
 250                 acc = -((LONGLONG_T) acc);
 251         if (endptr != 0)
 252                 *endptr = (char *) (any ? s - 1 : nptr);
 253         return acc;
 254 }