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/*****************************************
 * GOB File System
 *
 * Purpose: Provide fast, efficient disk access on a variety of platforms.
 * Implementation:
 *		The GOB system maintains two files -- GOB and GFC.  The GOB file is actually
 *		an archive of many files split into variable size, compressed blocks.  The GFC,
 *		GOB File Control, contains 3 tables -- a block table, basic file table, and
 *		extended file table.  The block table is analogous to a DOS FAT.  The basic
 *		file table contains a minimal set of file information to handle basic reading
 *		tasks.  The extended file table is optionally loaded and contains additional
 *		file information.  File names are case insensitive.
 *		  
 *		Files can be read in a normal manner.  Open, read, seek and close
 *		operations are all provided.  Files can only be written in a single
 *		contiguous chunk of blocks at the end of an archive.  Reads are processed
 *		through a configurable number of read ahead buffers to in an effort to
 *		minimize both reads and seeks.  Other operations including delete, verify, 
 *		access, and get size are also supported on files inside an archive.
 *
 *		The system supports read profiling.  By supplying a file read callback 
 *		function, the library will output the block number of each read.  This can 
 *		be used rearrange block in the archive to minimize seek times.  The 
 *		GOBRearrange sorts files in an archive.
 *
 *		Supports block based caching.  Primarily aimed at caching files off a DVD/CD
 *		to a faster hard disk.

#define GOB_MAGIC_IDENTIFIER		0x8008
#define GOB_MAX_FILE_NAME_LEN		96
#define GOB_MAX_FILES				(16*1024)
#define GOB_MAX_BLOCKS				32767
#define GOB_BLOCK_SIZE				(64*1024)
#define GOB_BLOCK_ALIGNMENT			2048
#define GOB_MEM_ALIGNMENT			64
#define GOB_COMPRESS_OVERHEAD		1024
#define GOBMARKER_STARTBLOCK		('L' | 'B' << 8 | 'T' << 16 | 'S' << 24)
#define GOBMARKER_ENDBLOCK			('L' | 'B' << 8 | 'N' << 16 | 'E' << 24)