lib/gstr.c

   1 /*
   2  *      Copyright (C) 2006 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
  25 /* These function are like strcat, strcpy. They only
  26  * do bounds checking (they shouldn't cause buffer overruns),
  27  * and they always produce null terminated strings.
  28  *
  29  * They should be used only with null terminated strings.
  30  */
  31 void _asn1_str_cat( char* dest, size_t dest_tot_size, const char* src) {
  32 size_t str_size = strlen(src);
  33 size_t dest_size = strlen(dest);
  34
  35         if ( dest_tot_size - dest_size > str_size) {
  36                 strcat( dest, src);
  37         } else {
  38                 if ( dest_tot_size - dest_size > 0) {
  39                         strncat( dest, src, (dest_tot_size - dest_size) -1);
  40                         dest[dest_tot_size-1] = 0;
  41                 }
  42         }
  43 }
  44
  45 void _asn1_str_cpy( char* dest, size_t dest_tot_size, const char* src) {
  46 size_t str_size = strlen(src);
  47
  48         if ( dest_tot_size > str_size) {
  49                 strcpy( dest, src);
  50         } else {
  51                 if ( dest_tot_size > 0) {
  52                         strncpy( dest, src, (dest_tot_size) -1);
  53                         dest[dest_tot_size-1] = 0;
  54                 }
  55         }
  56 }