//
// Copyright 2020 Electronic Arts Inc.
//
// TiberianDawn.DLL and RedAlert.dll and corresponding source code 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 3 of the License, or (at your option) any later version.
// TiberianDawn.DLL and RedAlert.dll and corresponding source code is distributed
// in the hope that it will be useful, but with permitted additional restrictions
// under Section 7 of the GPL. See the GNU General Public License in LICENSE.TXT
// distributed with this program. You should have received a copy of the
// GNU General Public License along with permitted additional restrictions
// with this program. If not, see https://github.com/electronicarts/CnC_Remastered_Collection
/* $Header: /CounterStrike/LZWOTRAW.CPP 1 3/03/97 10:25a Joe_bostic $ */
/***********************************************************************************************
*** C O N F I D E N T I A L --- W E S T W O O D S T U D I O S ***
***********************************************************************************************
* *
* Project Name : Command & Conquer *
* *
* File Name : LZWSTRAW.CPP *
* *
* Programmer : Joe L. Bostic *
* *
* Start Date : 07/02/96 *
* *
* Last Update : July 4, 1996 [JLB] *
* *
*---------------------------------------------------------------------------------------------*
* Functions: *
* LZWStraw::Get -- Fetch data through the LZW processor. *
* LZWStraw::LZWStraw -- Constructor for LZW straw object. *
* LZWStraw::~LZWStraw -- Destructor for the LZW straw. *
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
#include "lzostraw.h"
#include "lzwstraw.h"
#include "lzo.h"
#include <string.h>
#include <assert.h>
/***********************************************************************************************
* LZWStraw::LZWStraw -- Constructor for LZW straw object. *
* *
* This will initialize the LZW straw object. Whether the object is to compress or *
* decompress and the block size to use is specified. The data is compressed in blocks *
* that are sized to be quick to compress and yet still yield good compression ratios. *
* *
* INPUT: decrypt -- Should the data be decompressed? *
* *
* blocksize-- The size of the blocks to process. *
* *
* OUTPUT: none *
* *
* WARNINGS: It takes two buffers of the blocksize specified if compression is to be *
* performed. *
* *
* HISTORY: *
* 07/04/1996 JLB : Created. *
*=============================================================================================*/
LZWStraw::LZWStraw(CompControl control, int blocksize) :
Control(control),
Counter(0),
Buffer(NULL),
Buffer2(NULL),
BlockSize(blocksize)
{
SafetyMargin = BlockSize;
// SafetyMargin = BlockSize/128+1;
Buffer = new char[BlockSize+SafetyMargin];
if (control == COMPRESS) {
Buffer2 = new char[BlockSize+SafetyMargin];
}
}
/***********************************************************************************************
* LZWStraw::~LZWStraw -- Destructor for the LZW straw. *
* *
* The destructor will free up the allocated buffers that it allocated in the constructor. *
* *
* INPUT: none *
* *
* OUTPUT: none *
* *
* WARNINGS: none *
* *
* HISTORY: *
* 07/04/1996 JLB : Created. *
*=============================================================================================*/
LZWStraw::~LZWStraw(void)
{
delete [] Buffer;
Buffer = NULL;
delete [] Buffer2;
Buffer2 = NULL;
}
/***********************************************************************************************
* LZWStraw::Get -- Fetch data through the LZW processor. *
* *
* This routine will fetch the data bytes specified. It does this by first accumulating *
* a full block of data and then compressing or decompressing it as indicated. Subsequent *
* requests for data will draw from this buffer of processed data until it is exhausted *
* and another block must be fetched. *
* *
* INPUT: destbuf -- Pointer to the buffer to hold the data requested. *
* *
* length -- The number of data bytes requested. *
* *
* OUTPUT: Returns with the actual number of bytes stored into the buffer. If this number *
* is less than that requested, then this indicates that the data source has been *
* exhausted. *
* *
* WARNINGS: none *
* *
* HISTORY: *
* 07/04/1996 JLB : Created. *
*=============================================================================================*/
int LZWStraw::Get(void * destbuf, int slen)
{
assert(Buffer != NULL);
int total = 0;
/*
** Verify parameters for legality.
*/
if (destbuf == NULL || slen < 1) {
return(0);
}
while (slen > 0) {
/*
** Copy as much data is requested and available into the desired
** destination buffer.
*/
if (Counter) {
int len = (slen < Counter) ? slen : Counter;
if (Control == DECOMPRESS) {
memmove(destbuf, &Buffer[BlockHeader.UncompCount-Counter], len);
} else {
memmove(destbuf, &Buffer2[(BlockHeader.CompCount+sizeof(BlockHeader))-Counter], len);
}
destbuf = ((char *)destbuf) + len;
slen -= len;
Counter -= len;
total += len;
}
if (slen == 0) break;
if (Control == DECOMPRESS) {
int incount = Straw::Get(&BlockHeader, sizeof(BlockHeader));
if (incount != sizeof(BlockHeader)) break;
char *stageing_buffer = new char [BlockHeader.CompCount];
incount = Straw::Get(staging_buffer, BlockHeader.CompCount);
if (incount != BlockHeader.CompCount) break;
lz01x_decompress (ptr, BlockHeader.CompCount, Buffer, sizeof(Buffer), NULL);
Counter = BlockHeader.UncompCount;
} else {
BlockHeader.UncompCount = (unsigned short)Straw::Get(Buffer, BlockSize);
if (BlockHeader.UncompCount == 0) break;
int len = sizeof (Buffer2) - sizeof (BlockHeader);
char *dictionary = new char [64*1024];
lzo1x_1_compress (Buffer, BlockHeader.UncompCount, &Buffer2[sizeof(BlockHeader)], &BlockHeader.CompCount, dictionary);
delete [] dictionary;
memmove(Buffer2, &BlockHeader, sizeof(BlockHeader));
Counter = BlockHeader.CompCount+sizeof(BlockHeader);
}
}
return(total);
}