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/*
* Copyright (C) 2001, 2002, and 2003 Roy Keene
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* email: dact@rkeene.org
*/
/*
Example block compression routine for interfacing with DACT.
This does no compression.
(This is used as the minimum case, so block can be atmost blk_size
+3 bytes in size)
*/
#include "dact.h"
#include "comp_plain.h"
#include <stdio.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_STRING_H
#include <string.h>
#endif
/*
mode - DACT_MODE_COMPR or DACT_MODE_DECMP
Determine whether to compress or decompress.
prev_block - Previous (uncompressed) block.
curr_block - The data to be compressed.
out_block - Where to put data after compression.
blk_size - Size of prev_block and curr_block.
*/
int comp_plain_algo(int mode, unsigned char *prev_block, unsigned char *curr_block, char *out_block, int blk_size, int bufsize) {
switch(mode) {
case DACT_MODE_COMPR:
return(comp_plain_compress(prev_block, curr_block, out_block, blk_size, bufsize));
break; /* Heh */
case DACT_MODE_DECMP:
return(comp_plain_decompress(prev_block, curr_block, out_block, blk_size, bufsize));
break;
default:
printf("Unsupported mode: %i\n", mode);
return(-1);
}
}
int comp_plain_compress(unsigned char *prev_block, unsigned char *curr_block, char *out_block, int blk_size, int bufsize) {
memcpy(out_block,curr_block,blk_size);
return(blk_size);
}
int comp_plain_decompress(unsigned char *prev_block, unsigned char *curr_block, char *out_block, int blk_size, int bufsize) {
memcpy(out_block,curr_block,blk_size);
return(blk_size);
}
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