tldm-universe/Ardent/UV/gcidir/include/pi.lh.h

/******************************************************************************
*
*	Definitions for PI/open Dynamic (LH) files
*
*	Module	%M%	Version	%I% 	Date	%H%
*
*	(c) Copyright 1998 Ardent Software Inc. - All Rights Reserved
*	This is unpublished proprietary source code of Ardent Software Inc.
*	The copyright notice above does not evidence any actual or intended
*	publication of such source code.
*
*******************************************************************************
*
*	Maintenence log - insert most recent change descriptions at top
*
*	Date.... GTAR# WHO Description.........................................
*	10/14/98 23801 SAP Change copyrights. 
*	05/17/96 18433 WSM Changes to allow conversion on any platform.
*	06/21/94 14342 ALC Added new block type to detect files where
*				conversion started.
*	05/19/94 14011 ALC Added def's for AK file removal.
*	05/05/94 13934 ALC Removed unused detail.
*	10/20/93 12303 ALC Initial implementation
*				Module constructed from a number of PI/open
*				include files.
*
******************************************************************************/


/*
 * PI/open file configuration parameters
 */
#define MAX_BLOCK       4       /* maximum block allowed */
#define MAX_IDLEN	220	/* maximum PI/open ID length */
#define MAX_OPTIONS	10	/* Max number of UFS types supported */
#define OPTION_BUFFER_BYTES	800	/* Storage for option strings in hdr */
#define	LH_FIRSTINDEXSUBFILE	2	/* First AK index file suffix */	
#define	MAX_SUBFILES		256	/* Max AK suffix is 1 less */


/*
 * offsetof(): Constant expression the value of which is the offset in bytes
 * from the beginning of a structure 'type' of the member 'identifier'
 * (which cannot be a bit field).
 */
#if defined(offsetof)
#undef offsetof
#endif
#define offsetof(type, identifier) ((char*)&((type*)0)->identifier - (char*)0)


/*
 * Types of blocks in PI/open dynamic files
 */
#define BT_MINVALUE	29030	/* minimum legal type */
#define BT_FREEBLOCK	29030	/* block on free list */
#define BT_ALLOCBLOCK	29031	/* just allocated block */
#define BT_PRIMARY	29032	/* primary file header */
#define BT_OVERFLOW	29033	/* overflow file header */
#define BT_BUCKET	29034	/* bucket containing records */
#define BT_BIGRECORD	29035	/* data for a big record */
#define BT_OPTIONDATA	29036	/* data block for options like AK */
#define BT_MAXVALUE	29036	/* maximum legal type */
#define BT_CONVERTING	29037	/* Converting to uniVerse, illegal PI/open value */


/*
 * Macros to split block-number-size values into block numbers
 * and block sizes.  Block number is stored in lower 24 bits of
 * a bin(31), and block size is stored in upper 8 bits.
 */
#define BNS_MODVALUE    16777216 /* value to split block and size (2^24) */
#define HEADER_BLOCK    0       /* block number for file headers */


/*
 * Macros to build a bns value from a blocknumber and blocksize
 * and obtain the block number or block size from a bns value
 */
#define bns_number(bns)		((bns) % BNS_MODVALUE)
#define bns_size(bns)		((bns) / BNS_MODVALUE)


/*
 * Structure of block headers for each type of block.
 * This structure appears at the beginning of every type of block.
 * The first part of this structure is common among all types of
 * blocks.  Later parts of the definition describe variant sections
 * of the structure based on block type.
 */

typedef struct lh_params_t lh_params_t;
struct lh_params_t {
	short	b_hash;			/* which hash algorithm to use */
	short	b_bucketsize;		/* block size of each primary bucket */
	int	b_minmod;		/* smallest number of groups allowed */
	int	b_bigrecordchars;	/* data size for using big records */
	short	b_minload;		/* minimum desirable loading factor */
	short	b_maxload;		/* maximum desirable loading factor */
};

typedef struct lh_state_t lh_state_t;
struct lh_state_t {
	uint	b_modulus;		/* current number of groups in file */
	int	b_modvalue;		/* current power of two for split */
	int	b_nextsplit;		/* next bucket for splitting */
};

typedef struct lh_state2_t lh_state2_t;
struct lh_state2_t {
	int	b_loadwords;		/* non-big record words in the file */
};

typedef struct lh_fileinfo_t lh_fileinfo_t;
struct lh_fileinfo_t {
	lh_params_t	b_lhparams;	/* user selectable parameters */
	lh_state_t	b_lhstate;	/* written to file whenever changed */
	lh_state2_t	b_lhstate2;	/* written to file when closed */
};

typedef struct lh_options_t lh_options_t;
struct lh_options_t {
	int		b_optionblock[MAX_OPTIONS]; /* array of data pointers */
	char	        b_optionbuffer[OPTION_BUFFER_BYTES]; /* local storage for data */
};

typedef struct primary_block_t primary_block_t;
struct primary_block_t {
	lh_fileinfo_t	b_lhfileinfo;
	lh_options_t	b_options;      /* optional data for things like AK */
};

typedef struct overflow_block_t overflow_block_t;
struct overflow_block_t {
	int	b_blocks;		/* total number of blocks in overflow file */
	short	b_lastblocksize;	/* size of last block in file */
	int	b_freeblocks[MAX_BLOCK];  /* free list headers for free list */
	int	b_freecounts[MAX_BLOCK];  /* count of blocks in each list */
};

typedef struct bucket_block_t bucket_block_t;
struct bucket_block_t {
	int	b_groupnumber;		/* group number this bucket belongs to */
	short	b_records[1];		/* first location for record storage */
};

typedef struct bigrecord_block_t bigrecord_block_t;
struct bigrecord_block_t {
	int	b_hashvalue;		/* full hash value of record id this is for */
	char	b_recorddata[2];	/* first location of record data storage */
};

typedef struct optiondata_block_t optiondata_block_t;
struct optiondata_block_t {
	short	b_optiondatalen;	/* length of data string */
	char	b_optiondata[2];	/* data string */
};

typedef struct block_header_t block_header_t;
struct block_header_t {
	int	b_bns;			/* current block number and size */
	short	b_type;			/* block type */
	short	b_headerwords;		/* size of header (words) */
	int	b_sequence;		/* sequence number within a chain */
	int	b_nextbns;		/* next block number and size in chain of blocks */
	short	b_prevsize;		/* size of previous block */
	union b_vardata {
		primary_block_t		primary_block;
		overflow_block_t	overflow_block;
		bucket_block_t		bucket_block;
		bigrecord_block_t	bigrecord_block;
		optiondata_block_t	optiondata_block;
	} b_vardata;
};


/*
 * Format of a record.
 * The r_idlen field must be first, since it indicates the number of
 * words needed to examine the full record header including the id.
 * Negative values indicate deleted records or the end of the group.
 * The r_datablock field indicates where the data for the record is.
 * If zero, then the data begins on the next word after the record id.
 * If nonzero, then the data is in the specifed block number in the
 * overflow file, and this record ends after the record id.
 */
typedef struct record_header_t record_header_t;
struct record_header_t {
	short	r_idlen;	/* length of id (bytes) */
	int	r_nextrecord;	/* offset to next record header (words) */
	int	r_datalen;	/* length of record data (bytes) */
	int	r_bigdatabns;	/* big data block number and size, or zero */
	char	r_id[MAX_IDLEN]; /* storage for id (and possibly data) */
};


#define ID_DELETED      -1      /* special id value for deleted record */
#define ID_ENDGROUP     -2      /* special id value for end of group */
#define ID_ENDBLOCK     -3      /* special id value for end of current block */
#define ID_MINVALUE     -3      /* lowest magic id value */


/*
 * Record handling macros
 */

/* Return whether or not the record data is in large record blocks */
#define is_bigdata(rp) ((rp)->r_bigdatabns != 0)

/* Return whether or not this record is deleted */
#define is_deleted(rp) ((rp)->r_idlen == ID_DELETED)

/* Return whether or not this is the end of group */
#define is_endgroup(rp) ((rp)->r_idlen == ID_ENDGROUP)

/* Return whether or not this is the end of the block */
#define is_endblock(rp) ((rp)->r_idlen == ID_ENDBLOCK)


/*
 * Constants for handling PI/open UFS dynamic files
 * (partitioned, alternate key, and recoverable)
 */
#define FIRST_INDX_SUBFILE	2
#define NUM_AKFILES_FIELD	2
#define AU_FLAG_FIELD		3
#define FIRST_INDEX_FIELD	11
#define FIELD_NAME		2
#define NO_NULLS_FLAG		8


/*
 * Constant for determining the number of bytes in a primary block header
 */
#define PRIMARY_HEADER_BYTES	(offsetof(block_header_t, b_vardata) + sizeof(primary_block_t))

/*  END-CODE */