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Diffstat (limited to 'sot/source/sdstor/stgcache.cxx')
| -rw-r--r-- | sot/source/sdstor/stgcache.cxx | 430 |
1 files changed, 430 insertions, 0 deletions
diff --git a/sot/source/sdstor/stgcache.cxx b/sot/source/sdstor/stgcache.cxx new file mode 100644 index 000000000..93f7d3090 --- /dev/null +++ b/sot/source/sdstor/stgcache.cxx @@ -0,0 +1,430 @@ +/* -*- 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 . + */ + +#include <string.h> +#include <o3tl/safeint.hxx> +#include <osl/endian.h> +#include <osl/diagnose.h> + +#include <sot/stg.hxx> +#include "stgcache.hxx" + +#include <algorithm> + +////////////////////////////// class StgPage +// This class implements buffer functionality. The cache will always return +// a page buffer, even if a read fails. It is up to the caller to determine +// the correctness of the I/O. + +StgPage::StgPage( short nSize, sal_Int32 nPage ) + : mnPage( nPage ) + , mpData( new sal_uInt8[ nSize ] ) + , mnSize( nSize ) +{ + OSL_ENSURE( mnSize >= 512, "Unexpected page size is provided!" ); + // We will write this data to a permanent file later + // best to clear if first. + memset( mpData.get(), 0, mnSize ); +} + +StgPage::~StgPage() +{ +} + +rtl::Reference< StgPage > StgPage::Create( short nData, sal_Int32 nPage ) +{ + return rtl::Reference< StgPage >( new StgPage( nData, nPage ) ); +} + +void StgCache::SetToPage ( const rtl::Reference< StgPage >& rPage, short nOff, sal_Int32 nVal ) +{ + if( nOff >= 0 && ( o3tl::make_unsigned(nOff) < rPage->GetSize() / sizeof( sal_Int32 ) ) ) + { +#ifdef OSL_BIGENDIAN + nVal = OSL_SWAPDWORD(nVal); +#endif + static_cast<sal_Int32*>(rPage->GetData())[ nOff ] = nVal; + SetDirty( rPage ); + } +} + +bool StgPage::IsPageGreater( const StgPage *pA, const StgPage *pB ) +{ + return pA->mnPage < pB->mnPage; +} + +//////////////////////////////// class StgCache + +// The disk cache holds the cached sectors. The sector type differ according +// to their purpose. + +static sal_Int32 lcl_GetPageCount( sal_uInt64 nFileSize, short nPageSize ) +{ +// return (nFileSize >= 512) ? (nFileSize - 512) / nPageSize : 0; + // #i61980# real life: last page may be incomplete, return number of *started* pages + return (nFileSize >= 512) ? (nFileSize - 512 + nPageSize - 1) / nPageSize : 0; +} + +StgCache::StgCache() + : m_nError( ERRCODE_NONE ) + , m_nPages( 0 ) + , m_nRef( 0 ) + , m_nReplaceIdx( 0 ) + , maLRUPages( 8 ) // entries in the LRU lookup + , m_nPageSize( 512 ) + , m_pStorageStream( nullptr ) + , m_pStrm( nullptr ) + , m_bMyStream( false ) + , m_bFile( false ) +{ +} + +StgCache::~StgCache() +{ + Clear(); + SetStrm( nullptr, false ); +} + +void StgCache::SetPhysPageSize( short n ) +{ + OSL_ENSURE( n >= 512, "Unexpected page size is provided!" ); + if ( n >= 512 ) + { + m_nPageSize = n; + sal_uInt64 nFileSize = m_pStrm->TellEnd(); + m_nPages = lcl_GetPageCount( nFileSize, m_nPageSize ); + } +} + +// Create a new cache element + +rtl::Reference< StgPage > StgCache::Create( sal_Int32 nPg ) +{ + rtl::Reference< StgPage > xElem( StgPage::Create( m_nPageSize, nPg ) ); + maLRUPages[ m_nReplaceIdx++ % maLRUPages.size() ] = xElem; + return xElem; +} + +// Delete the given element + +void StgCache::Erase( const rtl::Reference< StgPage > &xElem ) +{ + OSL_ENSURE( xElem.is(), "The pointer should not be NULL!" ); + if ( xElem.is() ) { + auto it = std::find_if(maLRUPages.begin(), maLRUPages.end(), + [xElem](const rtl::Reference<StgPage>& rxPage) { return rxPage.is() && rxPage->GetPage() == xElem->GetPage(); }); + if (it != maLRUPages.end()) + it->clear(); + } +} + +// remove all cache elements without flushing them + +void StgCache::Clear() +{ + maDirtyPages.clear(); + for (auto& rxPage : maLRUPages) + rxPage.clear(); +} + +// Look for a cached page + +rtl::Reference< StgPage > StgCache::Find( sal_Int32 nPage ) +{ + auto it = std::find_if(maLRUPages.begin(), maLRUPages.end(), + [nPage](const rtl::Reference<StgPage>& rxPage) { return rxPage.is() && rxPage->GetPage() == nPage; }); + if (it != maLRUPages.end()) + return *it; + IndexToStgPage::iterator it2 = maDirtyPages.find( nPage ); + if ( it2 != maDirtyPages.end() ) + return it2->second; + return rtl::Reference< StgPage >(); +} + +// Load a page into the cache + +rtl::Reference< StgPage > StgCache::Get( sal_Int32 nPage, bool bForce ) +{ + rtl::Reference< StgPage > p = Find( nPage ); + if( !p.is() ) + { + p = Create( nPage ); + if( !Read( nPage, p->GetData() ) && bForce ) + { + Erase( p ); + p.clear(); + SetError( SVSTREAM_READ_ERROR ); + } + } + return p; +} + +// Copy an existing page into a new page. Use this routine +// to duplicate an existing stream or to create new entries. +// The new page is initially marked dirty. No owner is copied. + +rtl::Reference< StgPage > StgCache::Copy( sal_Int32 nNew, sal_Int32 nOld ) +{ + rtl::Reference< StgPage > p = Find( nNew ); + if( !p.is() ) + p = Create( nNew ); + if( nOld >= 0 ) + { + // old page: we must have this data! + rtl::Reference< StgPage > q = Get( nOld, true ); + if( q.is() ) + { + OSL_ENSURE( p->GetSize() == q->GetSize(), "Unexpected page size!" ); + memcpy( p->GetData(), q->GetData(), p->GetSize() ); + } + } + SetDirty( p ); + + return p; +} + +// Historically this wrote pages in a sorted, ascending order; +// continue that tradition. +bool StgCache::Commit() +{ + if ( Good() ) // otherwise Write does nothing + { + std::vector< StgPage * > aToWrite; + aToWrite.reserve(maDirtyPages.size()); + for (const auto& rEntry : maDirtyPages) + aToWrite.push_back( rEntry.second.get() ); + + std::sort( aToWrite.begin(), aToWrite.end(), StgPage::IsPageGreater ); + for (StgPage* pWr : aToWrite) + { + const rtl::Reference< StgPage > &pPage = pWr; + if ( !Write( pPage->GetPage(), pPage->GetData() ) ) + return false; + } + } + + maDirtyPages.clear(); + + m_pStrm->Flush(); + SetError( m_pStrm->GetError() ); + + return true; +} + +// Set a stream + +void StgCache::SetStrm( SvStream* p, bool bMy ) +{ + if( m_pStorageStream ) + { + m_pStorageStream->ReleaseRef(); + m_pStorageStream = nullptr; + } + + if( m_bMyStream ) + delete m_pStrm; + m_pStrm = p; + m_bMyStream = bMy; +} + +void StgCache::SetStrm( UCBStorageStream* pStgStream ) +{ + if( m_pStorageStream ) + m_pStorageStream->ReleaseRef(); + m_pStorageStream = pStgStream; + + if( m_bMyStream ) + delete m_pStrm; + + m_pStrm = nullptr; + + if ( m_pStorageStream ) + { + m_pStorageStream->AddFirstRef(); + m_pStrm = m_pStorageStream->GetModifySvStream(); + } + + m_bMyStream = false; +} + +void StgCache::SetDirty( const rtl::Reference< StgPage > &rPage ) +{ + assert( m_pStrm && m_pStrm->IsWritable() ); + maDirtyPages[ rPage->GetPage() ] = rPage; +} + +// Open/close the disk file + +bool StgCache::Open( const OUString& rName, StreamMode nMode ) +{ + // do not open in exclusive mode! + if( nMode & StreamMode::SHARE_DENYALL ) + nMode = ( ( nMode & ~StreamMode::SHARE_DENYALL ) | StreamMode::SHARE_DENYWRITE ); + SvFileStream* pFileStrm = new SvFileStream( rName, nMode ); + // SvStream "feature" Write Open also successful if it does not work + bool bAccessDenied = false; + if( ( nMode & StreamMode::WRITE ) && !pFileStrm->IsWritable() ) + { + pFileStrm->Close(); + bAccessDenied = true; + } + SetStrm( pFileStrm, true ); + if( pFileStrm->IsOpen() ) + { + sal_uInt64 nFileSize = m_pStrm->TellEnd(); + m_nPages = lcl_GetPageCount( nFileSize, m_nPageSize ); + m_pStrm->Seek( 0 ); + } + else + m_nPages = 0; + m_bFile = true; + SetError( bAccessDenied ? ERRCODE_IO_ACCESSDENIED : m_pStrm->GetError() ); + return Good(); +} + +void StgCache::Close() +{ + if( m_bFile ) + { + static_cast<SvFileStream*>(m_pStrm)->Close(); + SetError( m_pStrm->GetError() ); + } +} + +// low level I/O + +bool StgCache::Read( sal_Int32 nPage, void* pBuf ) +{ + sal_uInt32 nRead = 0, nBytes = m_nPageSize; + if( Good() ) + { + /* #i73846# real life: a storage may refer to a page one-behind the + last valid page (see document attached to the issue). In that case + (if nPage==nPages), just do nothing here and let the caller work on + the empty zero-filled buffer. */ + if ( nPage > m_nPages ) + SetError( SVSTREAM_READ_ERROR ); + else if ( nPage < m_nPages ) + { + sal_uInt32 nPos; + sal_Int32 nPg2; + // fixed address and size for the header + if( nPage == -1 ) + { + nPos = 0; + nPg2 = 1; + nBytes = 512; + } + else + { + nPos = Page2Pos(nPage); + nPg2 = ((nPage + 1) > m_nPages) ? m_nPages - nPage : 1; + } + + if (m_pStrm->Tell() != nPos) + m_pStrm->Seek(nPos); + + if (nPg2 != 1) + SetError(SVSTREAM_READ_ERROR); + else + { + nRead = m_pStrm->ReadBytes(pBuf, nBytes); + SetError(m_pStrm->GetError()); + } + } + } + + if (!Good()) + return false; + + if (nRead != nBytes) + memset(static_cast<sal_uInt8*>(pBuf) + nRead, 0, nBytes - nRead); + return true; +} + +bool StgCache::Write( sal_Int32 nPage, void const * pBuf ) +{ + if( Good() ) + { + sal_uInt32 nPos = Page2Pos( nPage ); + sal_uInt32 nBytes = m_nPageSize; + + // fixed address and size for the header + // nPageSize must be >= 512, otherwise the header can not be written here, we check it on import + if( nPage == -1 ) + { + nPos = 0; + nBytes = 512; + } + if( m_pStrm->Tell() != nPos ) + { + m_pStrm->Seek(nPos); + } + size_t nRes = m_pStrm->WriteBytes( pBuf, nBytes ); + if( nRes != nBytes ) + SetError( SVSTREAM_WRITE_ERROR ); + else + SetError( m_pStrm->GetError() ); + } + return Good(); +} + +// set the file size in pages + +bool StgCache::SetSize( sal_Int32 n ) +{ + // Add the file header + sal_Int32 nSize = n * m_nPageSize + 512; + m_pStrm->SetStreamSize( nSize ); + SetError( m_pStrm->GetError() ); + if( !m_nError ) + m_nPages = n; + return Good(); +} + +void StgCache::SetError( ErrCode n ) +{ + if( n && !m_nError ) + m_nError = n; +} + +void StgCache::ResetError() +{ + m_nError = ERRCODE_NONE; + m_pStrm->ResetError(); +} + +void StgCache::MoveError( StorageBase const & r ) +{ + if( m_nError != ERRCODE_NONE ) + { + r.SetError( m_nError ); + ResetError(); + } +} + +// Utility functions + +sal_Int32 StgCache::Page2Pos( sal_Int32 nPage ) const +{ + if( nPage < 0 ) nPage = 0; + return( nPage * m_nPageSize ) + m_nPageSize; +} + +/* vim:set shiftwidth=4 softtabstop=4 expandtab: */ |