compat/swab.c

   1 /*****************************************************************************
   2  * swab.c: swab() replacement
   3  *****************************************************************************
   4  * Copyright © 2009 VLC authors and VideoLAN
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU Lesser General Public License as published by
   8  * the Free Software Foundation; either version 2.1 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program 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
  14  * GNU Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public License
  17  * along with this program; if not, write to the Free Software Foundation,
  18  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  19  *****************************************************************************/
  20
  21 #ifdef HAVE_CONFIG_H
  22 # include <config.h>
  23 #endif
  24
  25 #include <stdlib.h>
  26 #include <stdint.h>
  27
  28 void swab( const void *p_src_, void *p_dst_, ssize_t n )
  29 {
  30     const uint8_t *p_src = p_src_;
  31     uint8_t *p_dst = p_dst_;
  32
  33     if( n < 0 )
  34         return;
  35
  36     for( ssize_t i = 0; i < n-1; i += 2 )
  37     {
  38         uint8_t i_tmp = p_src[i+0];
  39         p_dst[i+0] = p_src[i+1];
  40         p_dst[i+1] = i_tmp;
  41     }
  42 }
  43