l3lib/l3lib_vc6/llstream_modzip.h

//
// G A M E.O.N.E - LOW LEVEL LIB V1.0
// Copyright (C) 2001 LEVEL ONE ENTERTAINMENT, 
// Licensed under the terms of LGPL.
//:---------------------------------------------------------------------------
//:Description
//
// LOW LEVEL ZIP MODULE INCLUDE FILE
//
//:---------------------------------------------------------------------------

#ifndef _MODZIP_H
#define _MODZIP_H

#include "lib_base.h"
#include "llstream.h"



typedef TxU16 ush;
typedef TxU8 uch;
typedef TxU32 ulg;

typedef enum 
	{   NOT_INITIALIZED,			// do nothing
	 	COPY, 						// copy stored data
		INIT_BLOCK, 				// initialize next block to inflate
		INFLATE_CODES,				// decompress current block
		INFLATE_STORED,				// decompress current stored block
		INFLATE_END   				// all finished, do the cleanup
	}	eInflateStatus;
	

struct huft {
  uch e;                /* number of extra bits or operation */
  uch b;                /* number of bits in this code or subcode */
  union {
    ush n;              /* literal, length base, or distance base */
    struct huft *t;     /* pointer to next level of table */
  } v;
};


typedef struct directory
{
	char	*filename;
	long	crc;
	long	filepos;	
	long	uncompressed_size;
	long	compressed_size;
	short	method;
	int		offset; // offset zu daten wenn method=STORED. offset=grösse vom zipheader
	struct	directory	*next;
} directory;



class CModZipfile : public CStreamModule  
{
//-------------------------------------------------------------------------------------------------
//															construction / destruction		
//-------------------------------------------------------------------------------------------------
public:
	CModZipfile();
	virtual ~CModZipfile();

//-------------------------------------------------------------------------------------------------
//															public member functions	
//-------------------------------------------------------------------------------------------------
public:
	virtual		int	read(void *ioBuf, int iNum);
	virtual		int	write(void *ioBuf, int iNum);
	virtual		int		ioCtl( char *iCmd, void *ioOption );// send a command down the stream

	CStreamModule *Clone();
//-------------------------------------------------------------------------------------------------
//															instance variables	
//-------------------------------------------------------------------------------------------------
private:
	directory	*mDirectoryList;
	directory	*mSelectedFile;

//-------------------------------------------------------------------------------------------------
//															helper functions
//-------------------------------------------------------------------------------------------------
private:
	void	Reset(void);
	int		InitUnzip(void);
	int		BuildDirectory(void);
	void	DumpDir(void);
	int		SelectZipfile( char* iFilename );
	int	RetrieveBuffer(void *ioBuf, int iNum);
	void	CleanUp(void);

	void	ResetBufs(void);
	void	flush_window(void);
	TxU8 fillinbuf(int eof_ok);
	int 	huft_build (TxU32 *, TxU32, TxU32,
						ush *, ush *, struct huft **, int *);
	void	huft_free (struct huft *);
	int inflate_codes (void); //struct huft *, struct huft *, int, int);
	int inflate_stored (void);
	int inflate_fixed (void);
	int inflate_dynamic (void);
	int inflate_block (void);
	int inflate (void);
	TxU8 fill_inbuf(int eof_ok);                               


//-------------------------------------------------------------------------------------------------
//															buffer related variables
//-------------------------------------------------------------------------------------------------
private:                                        
	TxU8	*mOutbuf;		// Outputbuffer
	int		mOutcnt;		// num of bytes ready to flush
	int		mReadcnt;		// num of bytes removed from Outputbuffer
	
	int	mBytes_out;				// total number of decompressed bytes read
	int	mBytes_in;				// total number of compressed bytes read
	
	TxU8	*mInbuf;		// Inputbuffer
	int		mInptr;			// Read Index of Inputbuffer
	int		mInsize;		// number of bytes in Inputbuffer
	
	TxU16	*mDistbuf;		// Distance buffer
	TxU8	*mWindow;		// buffer to uncompressed file
	TxU16	*mTabprefix;	// ?
	TxU32	mCrc;			// crc shift register

//-------------------------------------------------------------------------------------------------
//															inflate related variables
//-------------------------------------------------------------------------------------------------
	eInflateStatus	mInflateStatus;	// controls reentrant inflate routines

	int 			mLastBlock;    	// last block flag 
  	int				mHufts;			// maximum struct huft's (h) malloc'ed
  	TxU32	mOrigCrc;		// crc reported from zipfile
  	int			mOrigLen;		// length reported from zipfile
	int			mCompLen;		// length of compressed file
	TxU32	mBitBuffer;		// bit buffer
	TxU32	mBits;			// bits in bit buffer
	int			mBlocksize;		// number of bytes in block  
	struct huft 	*mTl;			// literal/length tables
	struct huft 	*mTd;			// distance decoder tables
	int 			mBl;			// number of bits decoded by mTl[] 
	int 			mBd;			// number of bits decoded by mTd[]
	

//-------------------------------------------------------------------------------------------------
//															inflate codes related variables
//-------------------------------------------------------------------------------------------------
	TxU32 e;  			/* table entry flag/number of extra bits */
	TxU32 n, d;        	/* length and index for copy */
	struct huft *t;           	/* pointer to table entry */
	TxU32 ml, md;      	/* masks for bl and bd bits */
	  
	TxU32	hsrcl[288];     /* length list for huft_build */
	TxU32	hsrcd[288];     /* distance list for huft_build */
  
};

#endif // _MOD_ZIP_H