xref: /aoo41x/main/store/source/stordata.hxx (revision 1a5fa39b)

/**************************************************************
 *
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 *
 *************************************************************/



#ifndef _STORE_STORDATA_HXX_
#define _STORE_STORDATA_HXX_

#include "sal/types.h"
#include "sal/macros.h"

#include "store/types.h"
#include "storbase.hxx"

namespace store
{

/*========================================================================
 *
 * OStoreDataPageData.
 *
 *======================================================================*/
#define STORE_MAGIC_DATAPAGE sal_uInt32(0x94190310)

struct OStoreDataPageData : public store::OStorePageData
{
	typedef OStorePageData       base;
	typedef OStoreDataPageData   self;

	typedef OStorePageDescriptor D;

	/** Representation.
	*/
	sal_uInt8 m_pData[1];

    /** type.
     */
    static const sal_uInt32 theTypeId = STORE_MAGIC_DATAPAGE;

	/** size.
	*/
    static const size_t     theSize     = 0;
    static const sal_uInt16 thePageSize = base::theSize + self::theSize;
    STORE_STATIC_ASSERT(STORE_MINIMUM_PAGESIZE >= self::thePageSize);

	/** capacity.
	*/
	static sal_uInt16 capacity (const D& rDescr) // @see inode::ChunkDescriptor
	{
		return (store::ntohs(rDescr.m_nSize) - self::thePageSize);
	}
	sal_uInt16 capacity() const
	{
		return self::capacity (base::m_aDescr);
	}

	/** usage.
	*/
	sal_uInt16 usage() const
	{
		return (store::ntohs(base::m_aDescr.m_nUsed) - self::thePageSize);
	}

	/** Construction.
	*/
	explicit OStoreDataPageData (sal_uInt16 nPageSize = self::thePageSize)
		: base (nPageSize)
	{
		base::m_aGuard.m_nMagic = store::htonl(self::theTypeId);
		base::m_aDescr.m_nUsed  = store::htons(self::thePageSize);
		if (capacity()) memset (m_pData, 0, capacity());
	}

	/** guard (external representation).
	*/
	void guard() {}

	/** verify (external representation).
	*/
	storeError verify() const { return store_E_None; }
};

/*========================================================================
 *
 * OStoreDataPageObject.
 *
 *======================================================================*/
class OStoreDataPageObject : public store::OStorePageObject
{
	typedef OStorePageObject     base;
	typedef OStoreDataPageData   page;

public:
	/** Construction.
	*/
	explicit OStoreDataPageObject (PageHolder const & rxPage = PageHolder())
        : OStorePageObject (rxPage)
    {}

	/** External representation.
	 */
    virtual storeError guard  (sal_uInt32 nAddr);
    virtual storeError verify (sal_uInt32 nAddr) const;
};

/*========================================================================
 *
 * OStoreIndirectionPageData.
 *
 *======================================================================*/
#define STORE_MAGIC_INDIRECTPAGE sal_uInt32(0x89191107)

struct OStoreIndirectionPageData : public store::OStorePageData
{
	typedef OStorePageData            base;
	typedef OStoreIndirectionPageData self;

	typedef OStorePageGuard           G;
	typedef OStorePageDescriptor      D;

	/** Representation.
	*/
	G          m_aGuard;
	sal_uInt32 m_pData[1];

    /** type.
     */
    static const sal_uInt32 theTypeId = STORE_MAGIC_INDIRECTPAGE;

	/** size.
     */
    static const size_t     theSize     = sizeof(G);
    static const sal_uInt16 thePageSize = base::theSize + self::theSize;
    STORE_STATIC_ASSERT(STORE_MINIMUM_PAGESIZE >= self::thePageSize);

	/** capacity.
	*/
	static sal_uInt16 capacity (const D& rDescr)
	{
		return (store::ntohs(rDescr.m_nSize) - self::thePageSize);
	}
	sal_uInt16 capacity() const
	{
		return self::capacity (base::m_aDescr);
	}

	/** capacityCount.
	*/
	static sal_uInt16 capacityCount (const D& rDescr) // @see DirectoryPageObject::scope()
	{
		return sal_uInt16(capacity(rDescr) / sizeof(sal_uInt32));
	}
	sal_uInt16 capacityCount() const
	{
		return sal_uInt16(capacity() / sizeof(sal_uInt32));
	}

	/** Construction.
	*/
	explicit OStoreIndirectionPageData (sal_uInt16 nPageSize)
		: base (nPageSize)
	{
		base::m_aGuard.m_nMagic = store::htonl(self::theTypeId);
		base::m_aDescr.m_nUsed  = store::htons(self::thePageSize);
		self::m_aGuard.m_nMagic = store::htonl(0);
		memset (m_pData, STORE_PAGE_NULL, capacity());
	}

	/** guard (external representation).
	*/
	void guard()
	{
		sal_uInt32 nCRC32 = 0;
		nCRC32 = rtl_crc32 (nCRC32, &m_aGuard.m_nMagic, sizeof(sal_uInt32));
		nCRC32 = rtl_crc32 (nCRC32, m_pData, capacity());
		m_aGuard.m_nCRC32 = store::htonl(nCRC32);
	}

	/** verify (external representation).
	*/
	storeError verify() const
	{
		sal_uInt32 nCRC32 = 0;
		nCRC32 = rtl_crc32 (nCRC32, &m_aGuard.m_nMagic, sizeof(sal_uInt32));
		nCRC32 = rtl_crc32 (nCRC32, m_pData, capacity());
		if (m_aGuard.m_nCRC32 != store::htonl(nCRC32))
			return store_E_InvalidChecksum;
		else
			return store_E_None;
	}
};

/*========================================================================
 *
 * OStoreIndirectionPageObject.
 *
 *======================================================================*/
class OStoreIndirectionPageObject : public store::OStorePageObject
{
	typedef OStorePageObject          base;
	typedef OStoreIndirectionPageData page;

public:
	/** Construction.
	*/
    explicit OStoreIndirectionPageObject (PageHolder const & rxPage = PageHolder())
        : OStorePageObject (rxPage)
    {}

	/** External representation.
	*/
    storeError loadOrCreate (
        sal_uInt32       nAddr,
        OStorePageBIOS & rBIOS);

    virtual storeError guard  (sal_uInt32 nAddr);
    virtual storeError verify (sal_uInt32 nAddr) const;

	/** read (indirect data page).
	*/
	storeError read (
		sal_uInt16             nSingle,
		OStoreDataPageObject  &rData,
		OStorePageBIOS        &rBIOS);

	storeError read (
		sal_uInt16             nDouble,
		sal_uInt16             nSingle,
		OStoreDataPageObject  &rData,
		OStorePageBIOS        &rBIOS);

	storeError read (
		sal_uInt16             nTriple,
		sal_uInt16             nDouble,
		sal_uInt16             nSingle,
		OStoreDataPageObject  &rData,
		OStorePageBIOS        &rBIOS);

	/** write (indirect data page).
	*/
	storeError write (
		sal_uInt16             nSingle,
		OStoreDataPageObject  &rData,
		OStorePageBIOS        &rBIOS);

	storeError write (
		sal_uInt16             nDouble,
		sal_uInt16             nSingle,
		OStoreDataPageObject  &rData,
		OStorePageBIOS        &rBIOS);

	storeError write (
		sal_uInt16             nTriple,
		sal_uInt16             nDouble,
		sal_uInt16             nSingle,
		OStoreDataPageObject  &rData,
		OStorePageBIOS        &rBIOS);

	/** truncate (indirect data page).
	*/
	storeError truncate (
		sal_uInt16             nSingle,
		OStorePageBIOS        &rBIOS);

	storeError truncate (
		sal_uInt16             nDouble,
		sal_uInt16             nSingle,
		OStorePageBIOS        &rBIOS);

	storeError truncate (
		sal_uInt16             nTriple,
		sal_uInt16             nDouble,
		sal_uInt16             nSingle,
		OStorePageBIOS        &rBIOS);
};

/*========================================================================
 *
 * OStorePageNameBlock.
 *
 *======================================================================*/
struct OStorePageNameBlock
{
	typedef OStorePageGuard G;
	typedef OStorePageKey   K;

	/** Representation.
	*/
	G          m_aGuard;
	K          m_aKey;
	sal_uInt32 m_nAttrib;
	sal_Char   m_pData[STORE_MAXIMUM_NAMESIZE];

	/** size.
	*/
    static const size_t theSize = sizeof(G) + sizeof(K) + sizeof(sal_uInt32) + sizeof(sal_Char[STORE_MAXIMUM_NAMESIZE]);

	/** initialize.
	*/
	void initialize (void)
	{
		m_aGuard  = G();
		m_aKey    = K();
		m_nAttrib = 0;
		memset (m_pData, 0, sizeof(m_pData));
	}

	/** Construction.
	*/
	OStorePageNameBlock (void)
		: m_aGuard(), m_aKey(), m_nAttrib (0)
	{
		memset (m_pData, 0, sizeof(m_pData));
	}

	/** guard (external representation).
	*/
	void guard()
	{
		sal_uInt32 nCRC32 = 0;
		nCRC32 = rtl_crc32 (nCRC32, &m_aGuard.m_nMagic, sizeof(sal_uInt32));
		nCRC32 = rtl_crc32 (nCRC32, &m_aKey, theSize - sizeof(G));
		m_aGuard.m_nCRC32 = store::htonl(nCRC32);
	}

	/** verify (external representation).
	*/
	storeError verify() const
	{
		sal_uInt32 nCRC32 = 0;
		nCRC32 = rtl_crc32 (nCRC32, &m_aGuard.m_nMagic, sizeof(sal_uInt32));
		nCRC32 = rtl_crc32 (nCRC32, &m_aKey, theSize - sizeof(G));
		if (m_aGuard.m_nCRC32 != store::htonl(nCRC32))
			return store_E_InvalidChecksum;
		else
			return store_E_None;
	}
};

/*========================================================================
 *
 * OStoreDirectoryDataBlock.
 *
 *======================================================================*/
#define STORE_LIMIT_DATAPAGE_DIRECT 16
#define STORE_LIMIT_DATAPAGE_SINGLE  8
#define STORE_LIMIT_DATAPAGE_DOUBLE  1
#define STORE_LIMIT_DATAPAGE_TRIPLE  1

struct OStoreDirectoryDataBlock
{
	typedef OStorePageGuard G;

	/** LinkDescriptor.
	*/
	struct LinkDescriptor
	{
		/** Representation.
		*/
		sal_uInt16 m_nIndex0;
		sal_uInt16 m_nIndex1;
		sal_uInt16 m_nIndex2;
		sal_uInt16 m_nIndex3;

		/** Construction.
		*/
		LinkDescriptor (void)
			: m_nIndex0 ((sal_uInt16)(~0)),
			  m_nIndex1 ((sal_uInt16)(~0)),
			  m_nIndex2 ((sal_uInt16)(~0)),
			  m_nIndex3 ((sal_uInt16)(~0))
		{}
	};

	/** LinkTable.
	*/
	struct LinkTable
	{
		/** Representation.
		*/
		sal_uInt32 m_pDirect[STORE_LIMIT_DATAPAGE_DIRECT];
		sal_uInt32 m_pSingle[STORE_LIMIT_DATAPAGE_SINGLE];
		sal_uInt32 m_pDouble[STORE_LIMIT_DATAPAGE_DOUBLE];
		sal_uInt32 m_pTriple[STORE_LIMIT_DATAPAGE_TRIPLE];

		/** initialize.
		*/
		void initialize (void)
		{
		  memset(m_pDirect, STORE_PAGE_NULL, sizeof(m_pDirect));
		  memset(m_pSingle, STORE_PAGE_NULL, sizeof(m_pSingle));
		  memset(m_pDouble, STORE_PAGE_NULL, sizeof(m_pDouble));
		  memset(m_pTriple, STORE_PAGE_NULL, sizeof(m_pTriple));
		}

		/** Construction.
		*/
		LinkTable (void)
		{
		  initialize();
		}
	};

	/** Representation.
	*/
	G          m_aGuard;
	LinkTable  m_aTable;
	sal_uInt32 m_nDataLen;

	/** size.
     */
    static const size_t theSize = sizeof(G) + sizeof(LinkTable) + sizeof(sal_uInt32);

	/** initialize.
	*/
	void initialize (void)
	{
		m_aGuard = G();
		m_aTable.initialize();
		m_nDataLen = 0;
	}

	/** Construction.
	*/
	OStoreDirectoryDataBlock (void)
		: m_aGuard(), m_aTable(), m_nDataLen (0)
	{}

	/** guard (external representation).
	*/
	void guard()
	{
		sal_uInt32 nCRC32 = 0;
		nCRC32 = rtl_crc32 (nCRC32, &m_aGuard.m_nMagic, sizeof(sal_uInt32));
		nCRC32 = rtl_crc32 (nCRC32, &m_aTable, theSize - sizeof(G));
		m_aGuard.m_nCRC32 = store::htonl(nCRC32);
	}

	/** verify (external representation).
	*/
	storeError verify() const
	{
		sal_uInt32 nCRC32 = 0;
		nCRC32 = rtl_crc32 (nCRC32, &m_aGuard.m_nMagic, sizeof(sal_uInt32));
		nCRC32 = rtl_crc32 (nCRC32, &m_aTable, theSize - sizeof(G));
		if (m_aGuard.m_nCRC32 != store::htonl(nCRC32))
			return store_E_InvalidChecksum;
		else
			return store_E_None;
	}

	/** direct.
	*/
	static sal_uInt16 directCount (void)
	{
		return ((sal_uInt16)(STORE_LIMIT_DATAPAGE_DIRECT));
	}
	sal_uInt32 directLink (sal_uInt16 nIndex) const
	{
		if (nIndex < directCount())
			return store::ntohl(m_aTable.m_pDirect[nIndex]);
		else
			return STORE_PAGE_NULL;
	}
	void directLink (sal_uInt16 nIndex, sal_uInt32 nAddr)
	{
		if (nIndex < directCount())
			m_aTable.m_pDirect[nIndex] = store::htonl(nAddr);
	}

	/** single.
	*/
	static sal_uInt16 singleCount (void)
	{
		return ((sal_uInt16)(STORE_LIMIT_DATAPAGE_SINGLE));
	}
	sal_uInt32 singleLink (sal_uInt16 nIndex) const
	{
		if (nIndex < singleCount())
			return store::ntohl(m_aTable.m_pSingle[nIndex]);
		else
			return STORE_PAGE_NULL;
	}
	void singleLink (sal_uInt16 nIndex, sal_uInt32 nAddr)
	{
		if (nIndex < singleCount())
			m_aTable.m_pSingle[nIndex] = store::htonl(nAddr);
	}

	/** double.
	*/
	static sal_uInt16 doubleCount (void)
	{
		return ((sal_uInt16)(STORE_LIMIT_DATAPAGE_DOUBLE));
	}
	sal_uInt32 doubleLink (sal_uInt16 nIndex) const
	{
		if (nIndex < doubleCount())
			return store::ntohl(m_aTable.m_pDouble[nIndex]);
		else
			return STORE_PAGE_NULL;
	}
	void doubleLink (sal_uInt16 nIndex, sal_uInt32 nAddr)
	{
		if (nIndex < doubleCount())
			m_aTable.m_pDouble[nIndex] = store::htonl(nAddr);
	}

	/** triple.
	*/
	static sal_uInt16 tripleCount (void)
	{
		return ((sal_uInt16)(STORE_LIMIT_DATAPAGE_TRIPLE));
	}
	sal_uInt32 tripleLink (sal_uInt16 nIndex) const
	{
		if (nIndex < tripleCount())
			return store::ntohl(m_aTable.m_pTriple[nIndex]);
		else
			return STORE_PAGE_NULL;
	}
	void tripleLink (sal_uInt16 nIndex, sal_uInt32 nAddr)
	{
		if (nIndex < tripleCount())
			m_aTable.m_pTriple[nIndex] = store::htonl(nAddr);
	}
};

/*========================================================================
 *
 * OStoreDirectoryPageData.
 *
 *======================================================================*/
#define STORE_MAGIC_DIRECTORYPAGE sal_uInt32(0x62190120)

struct OStoreDirectoryPageData : public store::OStorePageData
{
	typedef OStorePageData           base;
	typedef OStoreDirectoryPageData  self;

	typedef OStorePageDescriptor     D;
	typedef OStorePageNameBlock      NameBlock;
	typedef OStoreDirectoryDataBlock DataBlock;

	/** Representation.
     */
	NameBlock m_aNameBlock;
	DataBlock m_aDataBlock;
	sal_uInt8 m_pData[1];

    /** type.
     */
    static const sal_uInt32 theTypeId = STORE_MAGIC_DIRECTORYPAGE;

	/** size.
     */
    static const size_t     theSize     = NameBlock::theSize + DataBlock::theSize;
    static const sal_uInt16 thePageSize = base::theSize + self::theSize;
    STORE_STATIC_ASSERT(STORE_MINIMUM_PAGESIZE >= self::thePageSize);

	/** capacity.
	*/
	sal_uInt16 capacity() const
	{
		return (store::ntohs(base::m_aDescr.m_nSize) - self::thePageSize);
	}

	/** usage.
	*/
	sal_uInt16 usage() const
	{
		return (store::ntohs(base::m_aDescr.m_nUsed) - self::thePageSize);
	}

	/** initialize.
	*/
	void initialize (void)
	{
		base::m_aGuard.m_nMagic = store::htonl(self::theTypeId);
		base::m_aDescr.m_nUsed  = store::htons(self::thePageSize);

		m_aNameBlock.initialize();
		m_aDataBlock.initialize();

		memset (m_pData, 0, capacity());
	}

	/** Construction.
	*/
	explicit OStoreDirectoryPageData (sal_uInt16 nPageSize)
		: base (nPageSize), m_aNameBlock(), m_aDataBlock()
	{
		base::m_aGuard.m_nMagic = store::htonl(self::theTypeId);
		base::m_aDescr.m_nUsed  = store::htons(self::thePageSize);
		memset (m_pData, 0, capacity());
	}

	/** guard (external representation).
	*/
	void guard()
	{
		m_aNameBlock.guard();
		m_aDataBlock.guard();
	}

	/** verify (external representation).
	*/
	storeError verify() const
	{
		storeError eErrCode = m_aNameBlock.verify();
		if (eErrCode == store_E_None)
			eErrCode = m_aDataBlock.verify();
		return eErrCode;
	}

	/** ChunkDescriptor.
	*/
	struct ChunkDescriptor
	{
		/** Representation.
		*/
		sal_uInt32 m_nPage;
		sal_uInt16 m_nOffset;
		sal_uInt16 m_nLength;

		/** Construction.
		*/
		ChunkDescriptor (sal_uInt32 nPosition, sal_uInt16 nCapacity)
		{
			m_nPage   = nPosition / nCapacity;
			m_nOffset = (sal_uInt16)((nPosition % nCapacity) & 0xffff);
			m_nLength = nCapacity - m_nOffset;
		}
	};

	/** ChunkScope.
	*/
	enum ChunkScope
	{
		SCOPE_INTERNAL,
		SCOPE_EXTERNAL,
		SCOPE_DIRECT,
		SCOPE_SINGLE,
		SCOPE_DOUBLE,
		SCOPE_TRIPLE,
		SCOPE_UNREACHABLE,
		SCOPE_UNKNOWN
	};

	/** scope (internal).
	*/
	ChunkScope scope (sal_uInt32 nPosition) const
	{
		sal_uInt32 nCapacity = capacity();
		if (nPosition < nCapacity)
			return SCOPE_INTERNAL;
		else
			return SCOPE_EXTERNAL;
	}
};

/*========================================================================
 *
 * OStoreDirectoryPageObject.
 *
 *======================================================================*/
class OStoreDirectoryPageObject : public store::OStorePageObject
{
	typedef OStorePageObject          base;
	typedef OStoreDirectoryPageData   page;
	typedef OStoreIndirectionPageData indirect;

	typedef OStorePageDescriptor      D;

public:
	/** Construction.
	*/
    explicit OStoreDirectoryPageObject (PageHolder const & rxPage = PageHolder())
        : OStorePageObject (rxPage)
    {}

	/** External representation.
	*/
	virtual storeError guard  (sal_uInt32 nAddr);
	virtual storeError verify (sal_uInt32 nAddr) const;

	/** attrib.
	*/
	sal_uInt32 attrib (void) const
	{
		return store::ntohl(PAGE().m_aNameBlock.m_nAttrib);
	}
	void attrib (sal_uInt32 nAttrib)
	{
		PAGE().m_aNameBlock.m_nAttrib = store::htonl(nAttrib);
		touch();
	}

	/** key.
	*/
	OStorePageKey key (void) const
	{
		return PAGE().m_aNameBlock.m_aKey;
	}
	void key (OStorePageKey const & rKey)
	{
		PAGE().m_aNameBlock.m_aKey = rKey;
		touch();
	}

	/** path.
	*/
	sal_uInt32 path (void) const
	{
        page const & rPage = PAGE();
		const sal_Char * pszName = rPage.m_aNameBlock.m_pData;
		sal_uInt32       nPath   = store::ntohl(rPage.m_aNameBlock.m_aKey.m_nHigh);
		return rtl_crc32 (nPath, pszName, rtl_str_getLength(pszName));
	}

    sal_Size getName (sal_Char * pBuffer, sal_Size nBufsiz) const
    {
        sal_Char const * pszName = PAGE().m_aNameBlock.m_pData;
        sal_Size nLength = rtl_str_getLength(pszName);
        memcpy (pBuffer, pszName, SAL_MIN(nLength, nBufsiz));
        return nLength;
    }

	/** dataLength.
	*/
	sal_uInt32 dataLength (void) const
	{
		return store::ntohl(PAGE().m_aDataBlock.m_nDataLen);
	}
	void dataLength (sal_uInt32 nLength)
	{
		PAGE().m_aDataBlock.m_nDataLen = store::htonl(nLength);
		touch();
	}

	/** direct.
	*/
	sal_uInt32 directLink (sal_uInt16 nIndex) const
	{
		return PAGE().m_aDataBlock.directLink (nIndex);
	}
	void directLink (sal_uInt16 nIndex, sal_uInt32 nAddr)
	{
		PAGE().m_aDataBlock.directLink (nIndex, nAddr);
		touch();
	}

	/** single indirect.
	*/
	sal_uInt32 singleLink (sal_uInt16 nIndex) const
	{
		return PAGE().m_aDataBlock.singleLink (nIndex);
	}
	void singleLink (sal_uInt16 nIndex, sal_uInt32 nAddr)
	{
		PAGE().m_aDataBlock.singleLink (nIndex, nAddr);
		touch();
	}

	/** double indirect.
	*/
	sal_uInt32 doubleLink (sal_uInt16 nIndex) const
	{
		return PAGE().m_aDataBlock.doubleLink (nIndex);
	}
	void doubleLink (sal_uInt16 nIndex, sal_uInt32 nAddr)
	{
		PAGE().m_aDataBlock.doubleLink (nIndex, nAddr);
		touch();
	}

	/** triple indirect.
	*/
	sal_uInt32 tripleLink (sal_uInt16 nIndex) const
	{
		return PAGE().m_aDataBlock.tripleLink (nIndex);
	}
	void tripleLink (sal_uInt16 nIndex, sal_uInt32 nAddr)
	{
		PAGE().m_aDataBlock.tripleLink (nIndex, nAddr);
		touch();
	}

	/** read (external data page).
	*/
	storeError read (
		sal_uInt32             nPage,
		OStoreDataPageObject  &rData,
		OStorePageBIOS        &rBIOS);

	/** write (external data page).
	*/
	storeError write (
		sal_uInt32             nPage,
		OStoreDataPageObject  &rData,
		OStorePageBIOS        &rBIOS);

	/** truncate (external data page).
	*/
	storeError truncate (
		sal_uInt32             nPage,
		OStorePageBIOS        &rBIOS);

private:
	/** Representation.
	*/
    page & PAGE()
    {
        page * pImpl = static_cast<page*>(m_xPage.get());
        OSL_PRECOND(pImpl != 0, "OStoreDirectoryPageObject::PAGE(): Null pointer");
        return (*pImpl);
    }
    page const & PAGE() const
    {
        page const * pImpl = static_cast<page const *>(m_xPage.get());
        OSL_PRECOND(pImpl != 0, "OStoreDirectoryPageObject::PAGE(): Null pointer");
        return (*pImpl);
    }

	/** scope (external data page; private).
	*/
	page::ChunkScope scope (
		sal_uInt32                       nPage,
		page::DataBlock::LinkDescriptor &rDescr) const;

	/** truncate (external data page scope; private).
	*/
	storeError truncate (
		page::ChunkScope       eScope,
		sal_uInt16             nRemain,
		OStorePageBIOS        &rBIOS);
};

/*========================================================================
 *
 * The End.
 *
 *======================================================================*/

} // namespace store

#endif /* !_STORE_STORDATA_HXX_ */