/****************************************************************************
 |
 |	(C) Copyright 1985, 1991, 1993, 1996-1999 Novell, Inc.
 |	All Rights Reserved.
 |
 |	This program is free software; you can redistribute it and/or
 |	modify it under the terms of version 2 of the GNU General Public
 |	License as published by the Free Software Foundation.
 |
 |	This program is distributed in the hope that it will be useful,
 |	but WITHOUT ANY WARRANTY; without even the implied warranty of
 |	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 |	GNU General Public License for more details.
 |
 |	You should have received a copy of the GNU General Public License
 |	along with this program; if not, contact Novell, Inc.
 |
 |	To contact Novell about this file by physical or electronic mail,
 |	you may find current contact information at www.novell.com
 |
 |***************************************************************************
 |
 |	 NSS Compression Management module
 |
 |---------------------------------------------------------------------------
 |
 | $Author: taysom $
 | $Date: 2004-12-31 01:10:58 +0530 (Fri, 31 Dec 2004) $
 |
 | $RCSfile$
 | $Revision: 465 $
 |
 |---------------------------------------------------------------------------
 |	Module Description:
 |
 +-------------------------------------------------------------------------*/
#ifndef _COMN_COMPRESS_H_
#define _COMN_COMPRESS_H_

#define COMP_METADATA_LAYOUT    1
/*
 * File/directory datastream's Compression Information
 * Stored in the rootBeast's RootVariableData area of uncompressed data streams.
 */
/* Persistent portion */
typedef struct PersistentCompressInfo_s
{
        Zid_t compZid;       /* ZID of the compressed stream's rootBeast */
        LONG chunkSize;      /* Compression Chunk size (0 means whole file) */

        /*
         * An (un)compressed version of a chunk is precious if it contains valid
         * user data and should not be discarded, either because it is the only
         * valid copy, or because the user told us not to discard it (eg, by
         * setting file attributes or through NetWare Set parameters)
         */
        LONG UCprecious;    /* # precious uncompressed chunks */
        LONG Cprecious;      /* # precious compressed chunks */
        Blknum_t purgeableBlks; /* # purgeable blocks currently contributed
                                 * by this beast to the volume's
                                 * VOLpurgeableBlks count */
        BYTE algoID;         /* Algorithm ID (Compression Manager-specific) */
        BYTE algoVersion;
        BYTE status;         /* Data stream's compression status */
#define COMP_STATUS_UNCOMPRESSED          0x1  /* Uncompressed data valid */
#define COMP_STATUS_COMPRESSED            0x2  /* Compressed data valid */
#define COMP_STATUS_FAILURE               0x4  /* Comp/decomp attempt
                                                * failed */
#define COMP_STATUS_CLEAN                 0x8  /* No extraneous data/metadata */
#define COMP_STATUS_NBITS                 4    /* #bits for chunk comp status */

#define CHUNK_COMPRESSED(_status)     ((_status) & COMP_STATUS_COMPRESSED)
#define CHUNK_UNCOMPRESSED(_status)   ((_status) & COMP_STATUS_UNCOMPRESSED)
#define ISVALID_COMP_CHUNK(_status)   CHUNK_COMPRESSED(_status)
#define ISVALID_UNCOMP_CHUNK(_status) CHUNK_UNCOMPRESSED(_status)
#define COMP_FAILED(_status)          ((_status) & COMP_STATUS_FAILURE)
#define BEAST_CLEAN(_status)          ((_status) & COMP_STATUS_CLEAN)
#define BEAST_COMPRESSED(_compInfo)   ((_compInfo)->p.UCprecious == 0)
#define BEAST_UNCOMPRESSED(_compInfo) ((_compInfo)->p.Cprecious == 0)
#define CHUNKY_COMPRESSION(_compInfo) ((_compInfo)->p.chunkSize != 0)

        BYTE action;		/* misc actions that has been taken */
#define COMP_ACTION_ADD_COMPLOG			  0x1  /* PLOG_BEAST_COMP_CLEANUP is added */
#define COMP_ACTION_ENABLE_IO_WRITE		  0x2  /* A write is done when ENABLE_IO_XXX */

} NSS_MEDIA_STRUCTURE(PersistentCompressInfo_s,action) PersistentCompressInfo_s;

typedef struct PackedCompInfo_s
{
    WORD rvdID;
    WORD rvdLayout;
    PersistentCompressInfo_s cmInfo;
} NSS_MEDIA_STRUCTURE(PackedCompInfo_s,cmInfo) PackedCompInfo_s;

typedef struct CompressInfo_s
{
    PersistentCompressInfo_s p; /* Persistent portion */

    /* Non-persistent portion */
    DQhead_t CM_activities; /* Head of list of ongoing (de)compression
                             * activities for this beast */
    DQhead_t dataWaiters;  /* Head of list of all threads waiting for
                             * uncompressed data to become available */
} CompressInfo_s;

typedef struct UncompressInfo_s
{
	Zid_t		uncompBeastZid;
	Zid_t		uncompParentZid;
	BOOL		uncompBeastDeleted;
} UncompressInfo_s;


#define MAX_ZIDS_PER_SCOOP 100

STATUS comnCompressInit();
void comnCompressUninit();

STATUS
compSetup(
        GeneralMsg_s *genMsg,
        RootBeast_s *uncompBeast,
        RootBeast_s **compBeast,    /* out */
        Xaction_s *xaction);

STATUS
compCleanup(
        GeneralMsg_s *genMsg,
        RootBeast_s *uncompBeast,
        RootBeast_s *compBeast,
        BOOL recovery,
        Xaction_s **xaction);

STATUS
decompSetup(
        GeneralMsg_s *genMsg,
        RootBeast_s *uncompBeast,
        Xaction_s *xaction);

STATUS
decompCleanup(
        GeneralMsg_s *genMsg,
        RootBeast_s *uncompBeast,
        RootBeast_s *compBeast,
        BOOL recovery,
        Xaction_s *xaction);

Buffer_s *
CM_fetchFileBlk(
        GeneralMsg_s *genMsg,
        RootBeast_s *beast,
        Blknum_t blknum,
        NINT mode,
        Blknum_t *holeBlks); /* out */

void
updateBeastPurgeableBlksCnt(
        GeneralMsg_s *genMsg,
        NamedBeast_s *beast,
        RootBeast_s *compBeast,
        BOOL includeCompBeastInfo, /* Include compBeast's blks also (if any) */
        Xaction_s *xaction);

STATUS setBeastCompAttr(
	RootBeast_s *uncompBeast,
	NINT desiredAttr,
	Xaction_s *xaction,
	BOOL commitChange);

void setVolCompStats(
	RootBeast_s *uncompBeast,
	RootBeast_s *compBeast,
	Xaction_s *xaction,
	BOOL addStats);

RootBeast_s *CM_LookupCompBeast(
	GeneralMsg_s	*genMsg,
    RootBeast_s		*beast,
    CompressInfo_s	*compInfo,
	NINT			latchType);
#endif /* _COMN_COMPRESS_H_ */