From b7e9f344715e39b0b48ec3471d40af2dd510572e Mon Sep 17 00:00:00 2001 From: Pavol Marko Date: Thu, 22 Jul 2004 13:05:03 +0000 Subject: [PATCH] Changed to use the miniLZO compression library --- amxmodx/amxxfile.cpp | 361 ++++--------------------------------------- amxmodx/amxxfile.h | 24 +-- 2 files changed, 32 insertions(+), 353 deletions(-) diff --git a/amxmodx/amxxfile.cpp b/amxmodx/amxxfile.cpp index 6ee4b94a..5ca740f1 100755 --- a/amxmodx/amxxfile.cpp +++ b/amxmodx/amxxfile.cpp @@ -31,341 +31,11 @@ #include "amxmodx.h" #include "amxxfile.h" -/***************** - ****** RLE ****** - *****************/ - -/************************************************************************* -* Name: rle.c -* Author: Marcus Geelnard -* Description: RLE coder/decoder implementation. -* Reentrant: Yes -* $Id$ -* -* RLE (Run Length Encoding) is the simplest possible lossless compression -* method. Nevertheless it serves a purpose, even in state of the art -* compression (it is used in JPEG compression, for instance). The basic -* principle is to identify sequences of equal bytes, and replace them with -* the byte in question and a repetition count (coded in some clever -* fashion). -* -* There are several different ways to do RLE. The particular method -* implemented here is a very efficient one. Instead of coding runs for -* both repeating and non-repeating sections, a special marker byte is -* used to indicate the start of a repeating section. Non-repeating -* sections can thus have any length without being interrupted by control -* bytes, except for the rare case when the special marker byte appears in -* the non-repeating section (which is coded with at most two bytes). For -* optimal efficiency, the marker byte is chosen as the least frequent -* (perhaps even non-existent) symbol in the input stream. -* -* Repeating runs can be as long as 32768 bytes. Runs shorter than 129 -* bytes require three bytes for coding (marker + count + symbol), whereas -* runs longer than 128 bytes require four bytes for coding (marker + -* counthi|0x80 + countlo + symbol). This is normally a win in compression, -* and it's very seldom a loss of compression ratio compared to using a -* fixed coding of three bytes (which allows coding a run of 256 bytes in -* just three bytes). -* -* With this scheme, the worst case compression result is -* (257/256)*insize + 1. -* -*------------------------------------------------------------------------- -* Note: This code is based on the code found in "codrle2.c" and -* "dcodrle2.c" by David Bourgin, as described in "Introduction to the -* losslessy compression schemes", 1994. The main differences from Davids -* implementation are the addition of long (15-bit) run counts, the removal -* of file I/O (this implementation works solely with preallocated memory -* buffers), and that the code is now 100% reentrant. -*------------------------------------------------------------------------- -* Copyright (c) 2003-2004 Marcus Geelnard -* -* This software is provided 'as-is', without any express or implied -* warranty. In no event will the authors be held liable for any damages -* arising from the use of this software. -* -* Permission is granted to anyone to use this software for any purpose, -* including commercial applications, and to alter it and redistribute it -* freely, subject to the following restrictions: -* -* 1. The origin of this software must not be misrepresented; you must not -* claim that you wrote the original software. If you use this software -* in a product, an acknowledgment in the product documentation would -* be appreciated but is not required. -* -* 2. Altered source versions must be plainly marked as such, and must not -* be misrepresented as being the original software. -* -* 3. This notice may not be removed or altered from any source -* distribution. -* -* Marcus Geelnard -* marcus.geelnard at home.se -*************************************************************************/ - -#include "amxxfile.h" - -/************************************************************************* -* INTERNAL FUNCTIONS * -*************************************************************************/ - - -/************************************************************************* -* _RLE_WriteRep() - Encode a repetition of 'symbol' repeated 'count' -* times. -*************************************************************************/ - -void CAmxxReader::_RLE_WriteRep( unsigned char *out, unsigned int *outpos, - unsigned char marker, unsigned char symbol, unsigned int count ) -{ - unsigned int i, idx; - - idx = *outpos; - if( count < 4 ) - { - if( symbol == marker ) - { - out[ idx ++ ] = marker; - out[ idx ++ ] = count-1; - if( count == 3 ) - { - out[ idx ++ ] = marker; - } - } - else - { - for( i = 0; i < count; ++ i ) - { - out[ idx ++ ] = symbol; - } - } - } - else - { - out[ idx ++ ] = marker; - -- count; - if( count >= 128 ) - { - out[ idx ++ ] = (count >> 8) | 0x80; - } - out[ idx ++ ] = count & 0xff; - out[ idx ++ ] = symbol; - } - *outpos = idx; -} - - -/************************************************************************* -* _RLE_WriteNonRep() - Encode a non-repeating symbol, 'symbol'. 'marker' -* is the marker symbol, and special care has to be taken for the case -* when 'symbol' == 'marker'. -*************************************************************************/ - -void CAmxxReader::_RLE_WriteNonRep( unsigned char *out, unsigned int *outpos, - unsigned char marker, unsigned char symbol ) -{ - unsigned int idx; - - idx = *outpos; - if( symbol == marker ) - { - out[ idx ++ ] = marker; - out[ idx ++ ] = 0; - } - else - { - out[ idx ++ ] = symbol; - } - *outpos = idx; -} - - - -/************************************************************************* -* PUBLIC FUNCTIONS * -*************************************************************************/ - - -/************************************************************************* -* RLE_Compress() - Compress a block of data using an RLE coder. -* in - Input (uncompressed) buffer. -* out - Output (compressed) buffer. This buffer must be 0.4% larger -* than the input buffer, plus one byte. -* insize - Number of input bytes. -* The function returns the size of the compressed data. -*************************************************************************/ - -int CAmxxReader::RLE_Compress( unsigned char *in, unsigned char *out, - unsigned int insize ) -{ - unsigned char byte1, byte2, marker; - unsigned int inpos, outpos, count, i, histogram[ 256 ]; - - /* Do we have anything to compress? */ - if( insize < 1 ) - { - return 0; - } - - /* Create histogram */ - for( i = 0; i < 256; ++ i ) - { - histogram[ i ] = 0; - } - for( i = 0; i < insize; ++ i ) - { - ++ histogram[ in[ i ] ]; - } - - /* Find the least common byte, and use it as the repetition marker */ - marker = 0; - for( i = 1; i < 256; ++ i ) - { - if( histogram[ i ] < histogram[ marker ] ) - { - marker = i; - } - } - - /* Remember the repetition marker for the decoder */ - out[ 0 ] = marker; - outpos = 1; - - /* Start of compression */ - byte1 = in[ 0 ]; - inpos = 1; - count = 1; - - /* Are there at least two bytes? */ - if( insize >= 2 ) - { - byte2 = in[ inpos ++ ]; - count = 2; - - /* Main compression loop */ - do - { - if( byte1 == byte2 ) - { - /* Do we meet only a sequence of identical bytes? */ - while( (inpos < insize) && (byte1 == byte2) && - (count < 32768) ) - { - byte2 = in[ inpos ++ ]; - ++ count; - } - if( byte1 == byte2 ) - { - _RLE_WriteRep( out, &outpos, marker, byte1, count ); - if( inpos < insize ) - { - byte1 = in[ inpos ++ ]; - count = 1; - } - else - { - count = 0; - } - } - else - { - _RLE_WriteRep( out, &outpos, marker, byte1, count-1 ); - byte1 = byte2; - count = 1; - } - } - else - { - /* No, then don't handle the last byte */ - _RLE_WriteNonRep( out, &outpos, marker, byte1 ); - byte1 = byte2; - count = 1; - } - if( inpos < insize ) - { - byte2 = in[ inpos ++ ]; - count = 2; - } - } - while( (inpos < insize) || (count >= 2) ); - } - - /* One byte left? */ - if( count == 1 ) - { - _RLE_WriteNonRep( out, &outpos, marker, byte1 ); - } - - return outpos; -} - - -/************************************************************************* -* RLE_Uncompress() - Uncompress a block of data using an RLE decoder. -* in - Input (compressed) buffer. -* out - Output (uncompressed) buffer. This buffer must be large -* enough to hold the uncompressed data. -* insize - Number of input bytes. -*************************************************************************/ - -void CAmxxReader::RLE_Uncompress( unsigned char *in, unsigned char *out, - unsigned int insize ) -{ - unsigned char marker, symbol; - unsigned int i, inpos, outpos, count; - - /* Do we have anything to compress? */ - if( insize < 1 ) - { - return; - } - - /* Get marker symbol from input stream */ - inpos = 0; - marker = in[ inpos ++ ]; - - /* Main decompression loop */ - outpos = 0; - do - { - symbol = in[ inpos ++ ]; - if( symbol == marker ) - { - /* We had a marker byte */ - count = in[ inpos ++ ]; - if( count < 3 ) - { - for( i = 0; i <= count; ++ i ) - { - out[ outpos ++ ] = marker; - } - } - else - { - if( count & 0x80 ) - { - count = ((count & 0x7f) << 8) + in[ inpos ++ ]; - } - symbol = in[ inpos ++ ]; - for( i = 0; i <= count; ++ i ) - { - out[ outpos ++ ] = symbol; - } - } - } - else - { - /* No marker, plain copy */ - out[ outpos ++ ] = symbol; - } - } - while( inpos < insize ); -} +#include "minilzo/minilzo.h" /********************** ****** AMXXFILE ****** **********************/ - #if defined __GNUC__ #define PACKED __attribute__((packed)) #else @@ -381,6 +51,13 @@ void CAmxxReader::RLE_Uncompress( unsigned char *in, unsigned char *out, #endif #endif +struct TableEntry +{ + CAmxxReader::mint8_t cellSize PACKED; + CAmxxReader::mint32_t origSize PACKED; // contains AMX_HEADER->stp + CAmxxReader::mint32_t offset PACKED; +}; + #define DATAREAD(addr, itemsize, itemcount) \ if (fread((addr), (itemsize), (itemcount), (m_pFile)) != (itemcount)) \ { \ @@ -403,6 +80,14 @@ CAmxxReader::CAmxxReader(const char *filename, int cellsize) m_Status = Err_None; m_CellSize = cellsize; + + // Make sure the decompressor runs + if (lzo_init() != LZO_E_OK) + { + m_Status = Err_DecompressorInit; + return; + } + m_pFile = fopen(filename, "rb"); if (!m_pFile) { @@ -567,9 +252,17 @@ CAmxxReader::Error CAmxxReader::GetSection(void *buffer) fseek(m_pFile, entry.offset, SEEK_SET); // read the data to a temporary buffer - char *tempBuffer = new char[m_SectionLength + 1]; - DATAREAD(static_cast(tempBuffer), 1, m_SectionLength); + lzo_byte *tempBuffer = new lzo_byte[m_SectionLength + 1]; + DATAREAD((void*)tempBuffer, 1, m_SectionLength); // decompress - RLE_Uncompress((unsigned char*)tempBuffer, (unsigned char*)(buffer), m_SectionLength); + lzo_uint destLen = GetBufferSize(); + int result = lzo1x_decompress_safe(tempBuffer, m_SectionLength, + (lzo_byte*)buffer, &destLen, + NULL /*unused*/ ); + if (result != LZO_E_OK) + { + m_Status = Err_Decompress; + return Err_Decompress; + } return Err_None; } \ No newline at end of file diff --git a/amxmodx/amxxfile.h b/amxmodx/amxxfile.h index e6640c98..ceee1c7c 100755 --- a/amxmodx/amxxfile.h +++ b/amxmodx/amxxfile.h @@ -42,30 +42,16 @@ public: Err_FileOpen, Err_FileRead, Err_FileInvalid, - Err_SectionNotFound + Err_SectionNotFound, + Err_DecompressorInit, + Err_Decompress }; -private: + typedef char mint8_t; typedef short mint16_t; typedef long mint32_t; - struct TableEntry - { - mint8_t cellSize; - mint32_t origSize; // contains AMX_HEADER->stp - mint32_t offset; - }; - - // These functions don't access members - static void _RLE_WriteRep(unsigned char *out, unsigned int *outpos, - unsigned char marker, unsigned char symbol, unsigned int count); - static void _RLE_WriteNonRep(unsigned char *out, unsigned int *outpos, - unsigned char marker, unsigned char symbol); - static int RLE_Compress(unsigned char *in, unsigned char *out, - unsigned int insize); - static void RLE_Uncompress(unsigned char *in, unsigned char *out, - unsigned int insize); - +private: Error m_Status; FILE *m_pFile;