lib/minitasn1/gstr.c

   1 /*
   2  * Copyright (C) 2006, 2007, 2008, 2009 Free Software Foundation
   3  * Copyright (C) 2002 Nikos Mavroyanopoulos
   4  *
   5  * This file is part of LIBTASN1.
   6  *
   7  * The LIBTASN1 library is free software; you can redistribute it
   8  * and/or modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this library; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  20  * 02110-1301, USA
  21  */
  22
  23 #include <int.h>
  24 #include "gstr.h"
  25
  26 /* These function are like strcat, strcpy. They only
  27  * do bounds checking (they shouldn't cause buffer overruns),
  28  * and they always produce null terminated strings.
  29  *
  30  * They should be used only with null terminated strings.
  31  */
  32 void
  33 _asn1_str_cat (char *dest, size_t dest_tot_size, const char *src)
  34 {
  35   size_t str_size = strlen (src);
  36   size_t dest_size = strlen (dest);
  37
  38   if (dest_tot_size - dest_size > str_size)
  39     {
  40       strcat (dest, src);
  41     }
  42   else
  43     {
  44       if (dest_tot_size - dest_size > 0)
  45         {
  46           strncat (dest, src, (dest_tot_size - dest_size) - 1);
  47           dest[dest_tot_size - 1] = 0;
  48         }
  49     }
  50 }
  51
  52 void
  53 _asn1_str_cpy (char *dest, size_t dest_tot_size, const char *src)
  54 {
  55   size_t str_size = strlen (src);
  56
  57   if (dest_tot_size > str_size)
  58     {
  59       strcpy (dest, src);
  60     }
  61   else
  62     {
  63       if (dest_tot_size > 0)
  64         {
  65           strncpy (dest, src, (dest_tot_size) - 1);
  66           dest[dest_tot_size - 1] = 0;
  67         }
  68     }
  69 }