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cde/cde/lib/DtMmdb/compression/huffman.h

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C++

/*
* CDE - Common Desktop Environment
*
* Copyright (c) 1993-2012, The Open Group. All rights reserved.
*
* These libraries and programs are free software; you can
* redistribute them and/or modify them under the terms of the GNU
* Lesser General Public License as published by the Free Software
* Foundation; either version 2 of the License, or (at your option)
* any later version.
*
* These libraries and programs are distributed in the hope that
* they will be useful, but WITHOUT ANY WARRANTY; without even the
* implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
* PURPOSE. See the GNU Lesser General Public License for more
* details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with these libraries and programs; if not, write
* to the Free Software Foundation, Inc., 51 Franklin Street, Fifth
* Floor, Boston, MA 02110-1301 USA
*/
/*
* $XConsortium: huffman.h /main/3 1996/06/11 17:15:11 cde-hal $
*
* Copyright (c) 1993 HAL Computer Systems International, Ltd.
* All rights reserved. Unpublished -- rights reserved under
* the Copyright Laws of the United States. USE OF A COPYRIGHT
* NOTICE IS PRECAUTIONARY ONLY AND DOES NOT IMPLY PUBLICATION
* OR DISCLOSURE.
*
* THIS SOFTWARE CONTAINS CONFIDENTIAL INFORMATION AND TRADE
* SECRETS OF HAL COMPUTER SYSTEMS INTERNATIONAL, LTD. USE,
* DISCLOSURE, OR REPRODUCTION IS PROHIBITED WITHOUT THE
* PRIOR EXPRESS WRITTEN PERMISSION OF HAL COMPUTER SYSTEMS
* INTERNATIONAL, LTD.
*
* RESTRICTED RIGHTS LEGEND
* Use, duplication, or disclosure by the Government is subject
* to the restrictions as set forth in subparagraph (c)(l)(ii)
* of the Rights in Technical Data and Computer Software clause
* at DFARS 252.227-7013.
*
* HAL COMPUTER SYSTEMS INTERNATIONAL, LTD.
* 1315 Dell Avenue
* Campbell, CA 95008
*
*/
#ifndef _huff_h
#define _huff_h 1
#include "compression/abs_agent.h"
#include "compression/trie.h"
////////////////////////////////////////
//
////////////////////////////////////////
class htr_node
{
public:
htr_node* left;
htr_node* right;
encoding_unit* eu;
unsigned long freq;
htr_node* parent;
public:
htr_node(encoding_unit* eu, htr_node* lt = 0, htr_node* rt = 0);
htr_node(unsigned long freq, htr_node* lt = 0, htr_node* rt = 0);
~htr_node();
};
////////////////////////////////////////
//
////////////////////////////////////////
class huff : public compress_agent
{
protected:
encoding_unit** e_units;
unsigned int cts ;
trie* tri;
htr_node* htr_root;
protected:
void build_tree();
void calculate_code();
encoding_unit* get_e_unit(unsigned char*& data, int len);
public:
huff();
virtual ~huff() ;
virtual void compress(const buffer& uncompressed, buffer& compressed) ;
virtual void decompress(buffer& compressed, buffer& uncompressed) ;
ostream& print_alphabet(ostream& out);
MMDB_SIGNATURES(huff);
// compacted disk representation In and Out functions
virtual int cdr_sizeof();
virtual io_status cdrOut(buffer&);
virtual io_status cdrIn(buffer&);
// get data to compute the alphabet
virtual io_status build_dict(lex_func_t f_lex, getchar_func_t f_getchar);
};
extern huff g_huff_agent;
#endif