lib/gstr.c

   1 /*
   2  *      Copyright (C) 2002 Nikos Mavroyanopoulos
   3  *
   4  * This file is part of LIBASN1.
   5  *
   6  * The LIBTASN1 library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,  USA
  19  */
  20
  21 #include <int.h>
  22
  23 /* These function are like strcat, strcpy. They only
  24  * do bounds checking (they shouldn't cause buffer overruns),
  25  * and they always produce null terminated strings.
  26  *
  27  * They should be used only with null terminated strings.
  28  */
  29 void _asn1_str_cat( char* dest, size_t dest_tot_size, const char* src) {
  30 size_t str_size = strlen(src);
  31 size_t dest_size = strlen(dest);
  32
  33         if ( dest_tot_size - dest_size > str_size) {
  34                 strcat( dest, src);
  35         } else {
  36                 if ( dest_tot_size - dest_size > 0) {
  37                         strncat( dest, src, (dest_tot_size - dest_size) -1);
  38                         dest[dest_tot_size-1] = 0;
  39                 }
  40         }
  41 }
  42
  43 void _asn1_str_cpy( char* dest, size_t dest_tot_size, const char* src) {
  44 size_t str_size = strlen(src);
  45
  46         if ( dest_tot_size > str_size) {
  47                 strcpy( dest, src);
  48         } else {
  49                 if ( dest_tot_size > 0) {
  50                         strncpy( dest, src, (dest_tot_size) -1);
  51                         dest[dest_tot_size-1] = 0;
  52                 }
  53         }
  54 }
  55
  56 void _asn1_mem_cpy( char* dest, size_t dest_tot_size, const char* src, size_t src_size)
  57 {
  58
  59         if ( dest_tot_size >= src_size) {
  60                 memcpy( dest, src, src_size);
  61         } else {
  62                 if ( dest_tot_size > 0) {
  63                         memcpy( dest, src, dest_tot_size);
  64                 }
  65         }
  66 }