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/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
* This file is part of the LibreOffice project.
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*
* This file incorporates work covered by the following license notice:
*
* 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 .
*/
#ifndef _STGSTRMS_HXX
#define _STGSTRMS_HXX
#include <tools/stream.hxx>
#include <vector>
class StgIo;
class StgStrm;
class StgPage;
class StgDirEntry;
// The FAT class performs FAT operations on an underlying storage stream.
// This stream is either the physical FAT stream (bPhys == sal_True ) or a normal
// storage stream, which then holds the FAT for small data allocations.
class StgFAT
{ // FAT allocator
StgStrm& rStrm; // underlying stream
sal_Int32 nMaxPage; // highest page allocated so far
short nPageSize; // physical page size
short nEntries; // FAT entries per page
short nOffset; // current offset within page
sal_Int32 nLimit; // search limit recommendation
sal_Bool bPhys; // sal_True: physical FAT
StgPage* GetPhysPage( sal_Int32 nPage );
sal_Bool MakeChain( sal_Int32 nStart, sal_Int32 nPages );
sal_Bool InitNew( sal_Int32 nPage1 );
public:
StgFAT( StgStrm& rStrm, sal_Bool bMark );
sal_Int32 FindBlock( sal_Int32& nPages );
sal_Int32 GetNextPage( sal_Int32 nPg );
sal_Int32 AllocPages( sal_Int32 nStart, sal_Int32 nPages );
sal_Bool FreePages( sal_Int32 nStart, sal_Bool bAll );
sal_Int32 GetMaxPage() { return nMaxPage; }
void SetLimit( sal_Int32 n ) { nLimit = n; }
};
// The base stream class provides basic functionality for seeking
// and accessing the data on a physical basis. It uses the built-in
// FAT class for the page allocations.
class StgStrm { // base class for all streams
protected:
StgIo& rIo; // I/O system
StgFAT* pFat; // FAT stream for allocations
StgDirEntry* pEntry; // dir entry (for ownership)
sal_Int32 nStart; // 1st data page
sal_Int32 nSize; // stream size in bytes
sal_Int32 nPos; // current byte position
sal_Int32 nPage; // current logical page
short nOffset; // offset into current page
short nPageSize; // logical page size
std::vector<sal_Int32> m_aPagesCache;
void scanBuildPageChainCache(sal_Int32 *pOptionalCalcSize = NULL);
sal_Bool Copy( sal_Int32 nFrom, sal_Int32 nBytes );
StgStrm( StgIo& );
public:
virtual ~StgStrm();
StgIo& GetIo() { return rIo; }
sal_Int32 GetPos() const { return nPos; }
sal_Int32 GetStart() const { return nStart; }
sal_Int32 GetSize() const { return nSize; }
sal_Int32 GetPage() const { return nPage; }
short GetPageSize() const { return nPageSize; }
sal_Int32 GetPages() const;
short GetOffset() const { return nOffset;}
void SetEntry( StgDirEntry& );
virtual sal_Bool SetSize( sal_Int32 );
virtual sal_Bool Pos2Page( sal_Int32 nBytePos );
virtual sal_Int32 Read( void*, sal_Int32 ) { return 0; }
virtual sal_Int32 Write( const void*, sal_Int32 ) { return 0; }
virtual StgPage* GetPhysPage( sal_Int32 nBytePos, sal_Bool bForce = sal_False );
virtual sal_Bool IsSmallStrm() const { return sal_False; }
};
// The FAT stream class provides physical access to the master FAT.
// Since this access is implemented as a StgStrm, we can use the
// FAT allocator.
class StgFATStrm : public StgStrm { // the master FAT stream
virtual sal_Bool Pos2Page( sal_Int32 nBytePos );
sal_Bool SetPage( short, sal_Int32 );
public:
StgFATStrm( StgIo& );
virtual ~StgFATStrm() {}
using StgStrm::GetPage;
sal_Int32 GetPage( short, sal_Bool, sal_uInt16 *pnMasterAlloc = 0);
virtual sal_Bool SetSize( sal_Int32 );
virtual StgPage* GetPhysPage( sal_Int32 nBytePos, sal_Bool bForce = sal_False );
};
// The stream has a size increment which normally is 1, but which can be
// set to any value is you want the size to be incremented by certain values.
class StgDataStrm : public StgStrm // a physical data stream
{
short nIncr; // size adjust increment
void Init( sal_Int32 nBgn, sal_Int32 nLen );
public:
StgDataStrm( StgIo&, sal_Int32 nBgn, sal_Int32 nLen=-1 );
StgDataStrm( StgIo&, StgDirEntry& );
void* GetPtr( sal_Int32 nPos, sal_Bool bForce, sal_Bool bDirty );
void SetIncrement( short n ) { nIncr = n ; }
virtual sal_Bool SetSize( sal_Int32 );
virtual sal_Int32 Read( void*, sal_Int32 );
virtual sal_Int32 Write( const void*, sal_Int32 );
};
// The small stream class provides access to streams with a size < 4096 bytes.
// This stream is a StgStream containing small pages. The FAT for this stream
// is also a StgStream. The start of the FAT is in the header at DataRootPage,
// the stream itself is pointed to by the root entry (it holds start & size).
class StgSmallStrm : public StgStrm // a logical data stream
{
StgStrm* pData; // the data stream
void Init( sal_Int32 nBgn, sal_Int32 nLen );
public:
StgSmallStrm( StgIo&, sal_Int32 nBgn, sal_Int32 nLen );
StgSmallStrm( StgIo&, StgDirEntry& );
virtual sal_Int32 Read( void*, sal_Int32 );
virtual sal_Int32 Write( const void*, sal_Int32 );
virtual sal_Bool IsSmallStrm() const { return sal_True; }
};
class StgTmpStrm : public SvMemoryStream
{
String aName;
SvFileStream* pStrm;
using SvMemoryStream::GetData;
virtual sal_uLong GetData( void* pData, sal_uLong nSize );
virtual sal_uLong PutData( const void* pData, sal_uLong nSize );
virtual sal_uLong SeekPos( sal_uLong nPos );
virtual void FlushData();
public:
StgTmpStrm( sal_uLong=16 );
~StgTmpStrm();
sal_Bool Copy( StgTmpStrm& );
void SetSize( sal_uLong );
sal_uLong GetSize() const;
};
#endif
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