lib/safe-atoi.c

   1 /* safe-atoi.c -- checked string-to-int conversion.
   2    Copyright (C) 2007, 2010 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation, either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16 */
  17
  18 #include <config.h>
  19 #include <limits.h>
  20 #include <stdlib.h>
  21 #include <errno.h>
  22
  23 #include "safe-atoi.h"
  24 #include "quotearg.h"
  25 #include "error.h"
  26
  27
  28 #if ENABLE_NLS
  29 # include <libintl.h>
  30 # define _(Text) gettext (Text)
  31 #else
  32 # define _(Text) Text
  33 #endif
  34 #ifdef gettext_noop
  35 # define N_(String) gettext_noop (String)
  36 #else
  37 /* See locate.c for explanation as to why not use (String) */
  38 # define N_(String) String
  39 #endif
  40
  41
  42 int
  43 safe_atoi (const char *s, enum quoting_style style)
  44 {
  45   long lval;
  46   char *end;
  47
  48   errno = 0;
  49   lval = strtol (s, &end, 10);
  50   if ( (LONG_MAX == lval) || (LONG_MIN == lval) )
  51     {
  52       /* max/min possible value, or an error. */
  53       if (errno == ERANGE)
  54         {
  55           /* too big, or too small. */
  56           error (EXIT_FAILURE, errno, "%s", s);
  57         }
  58       else
  59         {
  60           /* not a valid number */
  61           error (EXIT_FAILURE, errno, "%s", s);
  62         }
  63       /* Otherwise, we do a range chack against INT_MAX and INT_MIN
  64        * below.
  65        */
  66     }
  67
  68   if (lval > INT_MAX || lval < INT_MIN)
  69     {
  70       /* The number was in range for long, but not int. */
  71       errno = ERANGE;
  72       error (EXIT_FAILURE, errno, "%s", s);
  73     }
  74   else if (*end)
  75     {
  76       error (EXIT_FAILURE, errno, _("Unexpected suffix %s on %s"),
  77              quotearg_n_style (0, style, end),
  78              quotearg_n_style (1, style, s));
  79     }
  80   else if (end == s)
  81     {
  82       error (EXIT_FAILURE, errno, _("Expected an integer: %s"),
  83              quotearg_n_style (0, style, s));
  84     }
  85   return (int)lval;
  86 }