Adding upstream version 4:24.2.0.upstream/4%24.2.0

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 886 insertions, 0 deletions

diff --git a/store/source/lockbyte.cxx b/store/source/lockbyte.cxx
new file mode 100644
index 0000000000..87aefdbe41
--- /dev/null
+++ b/store/source/lockbyte.cxx
@@ -0,0 +1,886 @@
+/* -*- 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 "lockbyte.hxx"
+
+#include <sal/types.h>
+#include <osl/diagnose.h>
+#include <osl/file.h>
+#include <osl/process.h>
+#include <rtl/ustring.hxx>
+#include <sal/log.hxx>
+
+#include "object.hxx"
+#include "storbase.hxx"
+
+#include <memory>
+#include <string.h>
+
+using namespace store;
+
+storeError ILockBytes::initialize (rtl::Reference< PageData::Allocator > & rxAllocator, sal_uInt16 nPageSize)
+{
+    OSL_PRECOND((STORE_MINIMUM_PAGESIZE <= nPageSize) && (nPageSize <= STORE_MAXIMUM_PAGESIZE), "invalid PageSize");
+    return initialize_Impl (rxAllocator, nPageSize);
+}
+
+storeError ILockBytes::readPageAt (std::shared_ptr<PageData> & rPage, sal_uInt32 nOffset)
+{
+    OSL_PRECOND(!(nOffset == STORE_PAGE_NULL), "store::ILockBytes::readPageAt(): invalid Offset");
+    if (nOffset == STORE_PAGE_NULL)
+        return store_E_CantSeek;
+
+    return readPageAt_Impl (rPage, nOffset);
+}
+
+storeError ILockBytes::writePageAt (std::shared_ptr<PageData> const & rPage, sal_uInt32 nOffset)
+{
+    // [SECURITY:ValInput]
+    PageData const * pagedata = rPage.get();
+    OSL_PRECOND(!(pagedata == nullptr), "store::ILockBytes::writePageAt(): invalid Page");
+    if (pagedata == nullptr)
+        return store_E_InvalidParameter;
+
+    sal_uInt32 const offset = pagedata->location();
+    OSL_PRECOND(!(nOffset != offset), "store::ILockBytes::writePageAt(): inconsistent Offset");
+    if (nOffset != offset)
+        return store_E_InvalidParameter;
+
+    OSL_PRECOND(!(nOffset == STORE_PAGE_NULL), "store::ILockBytes::writePageAt(): invalid Offset");
+    if (nOffset == STORE_PAGE_NULL)
+        return store_E_CantSeek;
+
+    return writePageAt_Impl (rPage, nOffset);
+}
+
+storeError ILockBytes::readAt (sal_uInt32 nOffset, void * pBuffer, sal_uInt32 nBytes)
+{
+    // [SECURITY:ValInput]
+    sal_uInt8 * dst_lo = static_cast<sal_uInt8*>(pBuffer);
+    if (dst_lo == nullptr)
+        return store_E_InvalidParameter;
+
+    sal_uInt8 * dst_hi = dst_lo + nBytes;
+    if (dst_lo >= dst_hi)
+        return (dst_lo > dst_hi) ? store_E_InvalidParameter : store_E_None;
+
+    OSL_PRECOND(!(nOffset == STORE_PAGE_NULL), "store::ILockBytes::readAt(): invalid Offset");
+    if (nOffset == STORE_PAGE_NULL)
+        return store_E_CantSeek;
+
+    sal_uInt64 const src_size = static_cast<sal_uInt64>(nOffset) + nBytes;
+    if (src_size > SAL_MAX_UINT32)
+        return store_E_CantSeek;
+
+    return readAt_Impl (nOffset, dst_lo, nBytes);
+}
+
+storeError ILockBytes::writeAt (sal_uInt32 nOffset, void const * pBuffer, sal_uInt32 nBytes)
+{
+    // [SECURITY:ValInput]
+    sal_uInt8 const * src_lo = static_cast<sal_uInt8 const*>(pBuffer);
+    if (src_lo == nullptr)
+        return store_E_InvalidParameter;
+
+    sal_uInt8 const * src_hi = src_lo + nBytes;
+    if (src_lo >= src_hi)
+        return (src_lo > src_hi) ? store_E_InvalidParameter : store_E_None;
+
+    OSL_PRECOND(!(nOffset == STORE_PAGE_NULL), "store::ILockBytes::writeAt(): invalid Offset");
+    if (nOffset == STORE_PAGE_NULL)
+        return store_E_CantSeek;
+
+    sal_uInt64 const dst_size = static_cast<sal_uInt64>(nOffset) + nBytes;
+    if (dst_size > SAL_MAX_UINT32)
+        return store_E_CantSeek;
+
+    return writeAt_Impl (nOffset, src_lo, nBytes);
+}
+
+storeError ILockBytes::getSize (sal_uInt32 & rnSize)
+{
+    rnSize = 0;
+    return getSize_Impl (rnSize);
+}
+
+storeError ILockBytes::setSize (sal_uInt32 nSize)
+{
+    return setSize_Impl (nSize);
+}
+
+storeError ILockBytes::flush()
+{
+    return flush_Impl();
+}
+
+namespace store
+{
+
+namespace {
+
+struct FileHandle
+{
+    oslFileHandle m_handle;
+
+    FileHandle() : m_handle(nullptr) {}
+
+    bool operator != (FileHandle const & rhs)
+    {
+        return (m_handle != rhs.m_handle);
+    }
+
+    static storeError errorFromNative (oslFileError eErrno)
+    {
+        switch (eErrno)
+        {
+        case osl_File_E_None:
+            return store_E_None;
+
+        case osl_File_E_NOENT:
+            return store_E_NotExists;
+
+        case osl_File_E_ACCES:
+        case osl_File_E_PERM:
+            return store_E_AccessViolation;
+
+        case osl_File_E_AGAIN:
+        case osl_File_E_DEADLK:
+            return store_E_LockingViolation;
+
+        case osl_File_E_BADF:
+            return store_E_InvalidHandle;
+
+        case osl_File_E_INVAL:
+            return store_E_InvalidParameter;
+
+        case osl_File_E_NOMEM:
+            return store_E_OutOfMemory;
+
+        case osl_File_E_NOSPC:
+            return store_E_OutOfSpace;
+
+        case osl_File_E_OVERFLOW:
+            return store_E_CantSeek;
+
+        default:
+            return store_E_Unknown;
+        }
+    }
+
+    static sal_uInt32 modeToNative (storeAccessMode eAccessMode)
+    {
+        sal_uInt32 nFlags = 0;
+        switch (eAccessMode)
+        {
+        case storeAccessMode::Create:
+            nFlags |= osl_File_OpenFlag_Create;
+            [[fallthrough]];
+        case storeAccessMode::ReadWrite:
+            nFlags |= osl_File_OpenFlag_Write;
+            [[fallthrough]];
+        case storeAccessMode::ReadOnly:
+            nFlags |= osl_File_OpenFlag_Read;
+            break;
+        default:
+            OSL_PRECOND(false, "store::FileHandle: unknown storeAccessMode");
+        }
+        return nFlags;
+    }
+
+    storeError initialize (rtl_uString * pFilename, storeAccessMode eAccessMode)
+    {
+        // Verify arguments.
+        sal_uInt32 nFlags = modeToNative (eAccessMode);
+        if (!pFilename || !nFlags)
+            return store_E_InvalidParameter;
+
+        // Convert into FileUrl.
+        OUString aFileUrl;
+        if (osl_getFileURLFromSystemPath (pFilename, &(aFileUrl.pData)) != osl_File_E_None)
+        {
+            // Not system path. Assume file url.
+            rtl_uString_assign (&(aFileUrl.pData), pFilename);
+        }
+        if (!aFileUrl.startsWith("file://"))
+        {
+            // Not file url. Assume relative path.
+            OUString aCwdUrl;
+            (void) osl_getProcessWorkingDir (&(aCwdUrl.pData));
+
+            // Absolute file url.
+            (void) osl_getAbsoluteFileURL (aCwdUrl.pData, aFileUrl.pData, &(aFileUrl.pData));
+        }
+
+        // Acquire handle.
+        oslFileError result = osl_openFile (aFileUrl.pData, &m_handle, nFlags);
+        if (result == osl_File_E_EXIST)
+        {
+            // Already existing (O_CREAT | O_EXCL).
+            result = osl_openFile (aFileUrl.pData, &m_handle, osl_File_OpenFlag_Read | osl_File_OpenFlag_Write);
+            if ((result == osl_File_E_None) && (eAccessMode == storeAccessMode::Create))
+            {
+                // Truncate existing file.
+                result = osl_setFileSize (m_handle, 0);
+            }
+        }
+        if (result != osl_File_E_None)
+            return errorFromNative(result);
+        return store_E_None;
+    }
+
+    /** @see FileLockBytes destructor
+     */
+    static void closeFile (oslFileHandle hFile)
+    {
+        (void) osl_closeFile (hFile);
+    }
+
+    /** @see ResourceHolder<T>::destructor_type
+     */
+    struct CloseFile
+    {
+        void operator()(FileHandle & rFile) const
+        {
+            // Release handle.
+            closeFile (rFile.m_handle);
+            rFile.m_handle = nullptr;
+        }
+    };
+    typedef CloseFile destructor_type;
+};
+
+class FileLockBytes :
+    public store::OStoreObject,
+    public store::ILockBytes
+{
+    /** Representation.
+     */
+    oslFileHandle                         m_hFile;
+    sal_uInt32                            m_nSize;
+    rtl::Reference< PageData::Allocator > m_xAllocator;
+
+    storeError initSize_Impl (sal_uInt32 & rnSize);
+
+    /** ILockBytes implementation.
+     */
+    virtual storeError initialize_Impl (rtl::Reference< PageData::Allocator > & rxAllocator, sal_uInt16 nPageSize) override;
+
+    virtual storeError readPageAt_Impl (std::shared_ptr<PageData> & rPage, sal_uInt32 nOffset) override;
+    virtual storeError writePageAt_Impl (std::shared_ptr<PageData> const & rPage, sal_uInt32 nOffset) override;
+
+    virtual storeError readAt_Impl (sal_uInt32 nOffset, void * pBuffer, sal_uInt32 nBytes) override;
+    virtual storeError writeAt_Impl (sal_uInt32 nOffset, void const * pBuffer, sal_uInt32 nBytes) override;
+
+    virtual storeError getSize_Impl (sal_uInt32 & rnSize) override;
+    virtual storeError setSize_Impl (sal_uInt32 nSize) override;
+
+    virtual storeError flush_Impl() override;
+
+public:
+    /** Construction.
+     */
+    explicit FileLockBytes (FileHandle const & rFile);
+
+    FileLockBytes(const FileLockBytes&) = delete;
+    FileLockBytes& operator=(const FileLockBytes&) = delete;
+
+protected:
+    /** Destruction.
+     */
+    virtual ~FileLockBytes() override;
+};
+
+}
+
+} // namespace store
+
+FileLockBytes::FileLockBytes (FileHandle const & rFile)
+    : m_hFile (rFile.m_handle), m_nSize (SAL_MAX_UINT32)
+{
+}
+
+FileLockBytes::~FileLockBytes()
+{
+    FileHandle::closeFile (m_hFile);
+}
+
+storeError FileLockBytes::initSize_Impl (sal_uInt32 & rnSize)
+{
+    /* osl_getFileSize() uses slow 'fstat(h, &size)',
+     * instead of fast 'size = lseek(h, 0, SEEK_END)'.
+     * so, init size here, and track changes.
+     */
+    sal_uInt64 uSize = 0;
+    oslFileError result = osl_getFileSize (m_hFile, &uSize);
+    if (result != osl_File_E_None)
+        return FileHandle::errorFromNative(result);
+    if (uSize > SAL_MAX_UINT32)
+        return store_E_CantSeek;
+
+    rnSize = sal::static_int_cast<sal_uInt32>(uSize);
+    return store_E_None;
+}
+
+storeError FileLockBytes::initialize_Impl (rtl::Reference< PageData::Allocator > & rxAllocator, sal_uInt16 nPageSize)
+{
+    storeError result = initSize_Impl (m_nSize);
+    if (result != store_E_None)
+        return result;
+
+    result = PageData::Allocator::createInstance (rxAllocator, nPageSize);
+    if (result != store_E_None)
+        return result;
+
+    // @see readPageAt_Impl().
+    m_xAllocator = rxAllocator;
+    return store_E_None;
+}
+
+storeError FileLockBytes::readPageAt_Impl (std::shared_ptr<PageData> & rPage, sal_uInt32 nOffset)
+{
+    if (m_xAllocator.is())
+    {
+        std::shared_ptr<PageData> page (m_xAllocator->construct<PageData>(), PageData::Deallocate(m_xAllocator));
+        page.swap (rPage);
+    }
+
+    if (!m_xAllocator.is())
+        return store_E_InvalidAccess;
+    if (!rPage)
+        return store_E_OutOfMemory;
+
+    PageData * pagedata = rPage.get();
+    return readAt_Impl (nOffset, pagedata, pagedata->size());
+}
+
+storeError FileLockBytes::writePageAt_Impl (std::shared_ptr<PageData> const & rPage, sal_uInt32 nOffset)
+{
+    PageData const * pagedata = rPage.get();
+    OSL_PRECOND(pagedata != nullptr, "contract violation");
+    return writeAt_Impl (nOffset, pagedata, pagedata->size());
+}
+
+storeError FileLockBytes::readAt_Impl (sal_uInt32 nOffset, void * pBuffer, sal_uInt32 nBytes)
+{
+    sal_uInt64 nDone = 0;
+    oslFileError result = osl_readFileAt (m_hFile, nOffset, pBuffer, nBytes, &nDone);
+    if (result != osl_File_E_None)
+        return FileHandle::errorFromNative(result);
+    if (nDone != nBytes)
+        return (nDone != 0) ? store_E_CantRead : store_E_NotExists;
+    return store_E_None;
+}
+
+storeError FileLockBytes::writeAt_Impl (sal_uInt32 nOffset, void const * pBuffer, sal_uInt32 nBytes)
+{
+    sal_uInt64 nDone = 0;
+    oslFileError result = osl_writeFileAt (m_hFile, nOffset, pBuffer, nBytes, &nDone);
+    if (result != osl_File_E_None)
+        return FileHandle::errorFromNative(result);
+    if (nDone != nBytes)
+        return store_E_CantWrite;
+
+    sal_uInt64 const uSize = nOffset + nBytes;
+    OSL_PRECOND(uSize < SAL_MAX_UINT32, "store::ILockBytes::writeAt() contract violation");
+    if (uSize > m_nSize)
+        m_nSize = sal::static_int_cast<sal_uInt32>(uSize);
+    return store_E_None;
+}
+
+storeError FileLockBytes::getSize_Impl (sal_uInt32 & rnSize)
+{
+    rnSize = m_nSize;
+    return store_E_None;
+}
+
+storeError FileLockBytes::setSize_Impl (sal_uInt32 nSize)
+{
+    oslFileError result = osl_setFileSize (m_hFile, nSize);
+    if (result != osl_File_E_None)
+        return FileHandle::errorFromNative(result);
+
+    m_nSize = nSize;
+    return store_E_None;
+}
+
+storeError FileLockBytes::flush_Impl()
+{
+    oslFileError result = osl_syncFile (m_hFile);
+    if (result != osl_File_E_None)
+        return FileHandle::errorFromNative(result);
+    return store_E_None;
+}
+
+/*========================================================================
+ *
+ * MappedLockBytes implementation.
+ *
+ *======================================================================*/
+namespace store
+{
+
+namespace {
+
+struct FileMapping
+{
+    sal_uInt8 * m_pAddr;
+    sal_uInt32  m_nSize;
+    oslFileHandle m_hFile;
+
+    FileMapping() : m_pAddr(nullptr), m_nSize(0), m_hFile(nullptr) {}
+
+    bool operator != (FileMapping const & rhs) const
+    {
+        return ((m_pAddr != rhs.m_pAddr) || (m_nSize != rhs.m_nSize));
+    }
+
+    oslFileError initialize (oslFileHandle hFile)
+    {
+        // Determine mapping size.
+        sal_uInt64   uSize  = 0;
+        oslFileError result = osl_getFileSize (hFile, &uSize);
+        if (result != osl_File_E_None)
+            return result;
+
+        // [SECURITY:IntOver]
+        if (uSize > SAL_MAX_UINT32)
+            return osl_File_E_OVERFLOW;
+        m_nSize = sal::static_int_cast<sal_uInt32>(uSize);
+
+        m_hFile = hFile;
+
+        // Acquire mapping.
+        return osl_mapFile (hFile, reinterpret_cast<void**>(&m_pAddr), m_nSize, 0, osl_File_MapFlag_RandomAccess);
+    }
+
+    /** @see MappedLockBytes::destructor.
+     */
+    static void unmapFile (oslFileHandle hFile, sal_uInt8 * pAddr, sal_uInt32 nSize)
+    {
+        (void) osl_unmapMappedFile (hFile, pAddr, nSize);
+        (void) osl_closeFile (hFile);
+    }
+
+    /** @see ResourceHolder<T>::destructor_type
+     */
+    struct UnmapFile
+    {
+        void operator ()(FileMapping & rMapping) const
+        {
+            // Release mapping.
+            unmapFile (rMapping.m_hFile, rMapping.m_pAddr, rMapping.m_nSize);
+            rMapping.m_pAddr = nullptr;
+            rMapping.m_nSize = 0;
+        }
+    };
+    typedef UnmapFile destructor_type;
+};
+
+class MappedLockBytes :
+    public store::OStoreObject,
+    public store::PageData::Allocator,
+    public store::ILockBytes
+{
+    /** Representation.
+     */
+    sal_uInt8 * m_pData;
+    sal_uInt32  m_nSize;
+    sal_uInt16  m_nPageSize;
+    oslFileHandle m_hFile;
+
+    /** PageData::Allocator implementation.
+     */
+    virtual void allocate_Impl (void ** ppPage, sal_uInt16 * pnSize) override;
+    virtual void deallocate_Impl (void * pPage) override;
+
+    /** ILockBytes implementation.
+     */
+    virtual storeError initialize_Impl (rtl::Reference< PageData::Allocator > & rxAllocator, sal_uInt16 nPageSize) override;
+
+    virtual storeError readPageAt_Impl (std::shared_ptr<PageData> & rPage, sal_uInt32 nOffset) override;
+    virtual storeError writePageAt_Impl (std::shared_ptr<PageData> const & rPage, sal_uInt32 nOffset) override;
+
+    virtual storeError readAt_Impl  (sal_uInt32 nOffset, void * pBuffer, sal_uInt32 nBytes) override;
+    virtual storeError writeAt_Impl (sal_uInt32 nOffset, const void * pBuffer, sal_uInt32 nBytes) override;
+
+    virtual storeError getSize_Impl (sal_uInt32 & rnSize) override;
+    virtual storeError setSize_Impl (sal_uInt32 nSize) override;
+
+    virtual storeError flush_Impl() override;
+
+public:
+    /** Construction.
+     */
+    explicit MappedLockBytes (FileMapping const & rMapping);
+
+    MappedLockBytes(const MappedLockBytes&) = delete;
+    MappedLockBytes& operator=(const MappedLockBytes&) = delete;
+
+protected:
+    /* Destruction.
+     */
+    virtual ~MappedLockBytes() override;
+};
+
+}
+
+} // namespace store
+
+MappedLockBytes::MappedLockBytes (FileMapping const & rMapping)
+    : m_pData (rMapping.m_pAddr), m_nSize (rMapping.m_nSize), m_nPageSize(0), m_hFile (rMapping.m_hFile)
+{
+}
+
+MappedLockBytes::~MappedLockBytes()
+{
+    FileMapping::unmapFile (m_hFile, m_pData, m_nSize);
+}
+
+void MappedLockBytes::allocate_Impl (void ** ppPage, sal_uInt16 * pnSize)
+{
+    OSL_PRECOND((ppPage != nullptr) && (pnSize != nullptr), "contract violation");
+    if ((ppPage != nullptr) && (pnSize != nullptr))
+    {
+        *ppPage = nullptr;
+        *pnSize = m_nPageSize;
+    }
+}
+
+void MappedLockBytes::deallocate_Impl (void * pPage)
+{
+    OSL_PRECOND((m_pData <= pPage) && (pPage < m_pData + m_nSize), "contract violation");
+}
+
+storeError MappedLockBytes::initialize_Impl (rtl::Reference< PageData::Allocator > & rxAllocator, sal_uInt16 nPageSize)
+{
+    rxAllocator = this;
+    m_nPageSize = nPageSize;
+    return store_E_None;
+}
+
+storeError MappedLockBytes::readPageAt_Impl (std::shared_ptr<PageData> & rPage, sal_uInt32 nOffset)
+{
+    sal_uInt8 * src_lo = m_pData + nOffset;
+    if ((m_pData > src_lo) || (src_lo >= m_pData + m_nSize))
+        return store_E_NotExists;
+
+    sal_uInt8 * src_hi = src_lo + m_nPageSize;
+    if ((m_pData > src_hi) || (src_hi > m_pData + m_nSize))
+        return store_E_CantRead;
+
+    std::shared_ptr<PageData> page (reinterpret_cast< PageData* >(src_lo), PageData::Deallocate(static_cast< PageData::Allocator* >(this)));
+    page.swap (rPage);
+
+    return store_E_None;
+}
+
+storeError MappedLockBytes::writePageAt_Impl (std::shared_ptr<PageData> const & /*rPage*/, sal_uInt32 /*nOffset*/)
+{
+    return store_E_AccessViolation;
+}
+
+storeError MappedLockBytes::readAt_Impl (sal_uInt32 nOffset, void * pBuffer, sal_uInt32 nBytes)
+{
+    sal_uInt8 const * src_lo = m_pData + nOffset;
+    if ((m_pData > src_lo) || (src_lo >= m_pData + m_nSize))
+        return store_E_NotExists;
+
+    sal_uInt8 const * src_hi = src_lo + nBytes;
+    if ((m_pData > src_hi) || (src_hi > m_pData + m_nSize))
+        return store_E_CantRead;
+
+    memcpy (pBuffer, src_lo, (src_hi - src_lo));
+    return store_E_None;
+}
+
+storeError MappedLockBytes::writeAt_Impl (sal_uInt32 /*nOffset*/, void const * /*pBuffer*/, sal_uInt32 /*nBytes*/)
+{
+    return store_E_AccessViolation;
+}
+
+storeError MappedLockBytes::getSize_Impl (sal_uInt32 & rnSize)
+{
+    rnSize = m_nSize;
+    return store_E_None;
+}
+
+storeError MappedLockBytes::setSize_Impl (sal_uInt32 /*nSize*/)
+{
+    return store_E_AccessViolation;
+}
+
+storeError MappedLockBytes::flush_Impl()
+{
+    return store_E_None;
+}
+
+namespace store
+{
+
+namespace {
+
+class MemoryLockBytes :
+    public store::OStoreObject,
+    public store::ILockBytes
+{
+    /** Representation.
+     */
+    sal_uInt8 * m_pData;
+    sal_uInt32  m_nSize;
+    rtl::Reference< PageData::Allocator > m_xAllocator;
+
+    /** ILockBytes implementation.
+     */
+    virtual storeError initialize_Impl (rtl::Reference< PageData::Allocator > & rxAllocator, sal_uInt16 nPageSize) override;
+
+    virtual storeError readPageAt_Impl (std::shared_ptr<PageData> & rPage, sal_uInt32 nOffset) override;
+    virtual storeError writePageAt_Impl (std::shared_ptr<PageData> const & rPage, sal_uInt32 nOffset) override;
+
+    virtual storeError readAt_Impl  (sal_uInt32 nOffset, void * pBuffer, sal_uInt32 nBytes) override;
+    virtual storeError writeAt_Impl (sal_uInt32 nOffset, const void * pBuffer, sal_uInt32 nBytes) override;
+
+    virtual storeError getSize_Impl (sal_uInt32 & rnSize) override;
+    virtual storeError setSize_Impl (sal_uInt32 nSize) override;
+
+    virtual storeError flush_Impl() override;
+
+public:
+    /** Construction.
+     */
+    MemoryLockBytes();
+
+    MemoryLockBytes(const MemoryLockBytes&) = delete;
+    MemoryLockBytes& operator=(const MemoryLockBytes&) = delete;
+
+protected:
+    virtual ~MemoryLockBytes() override;
+};
+
+}
+
+} // namespace store
+
+MemoryLockBytes::MemoryLockBytes()
+    : m_pData (nullptr), m_nSize (0)
+{}
+
+MemoryLockBytes::~MemoryLockBytes()
+{
+    std::free (m_pData);
+}
+
+storeError MemoryLockBytes::initialize_Impl (rtl::Reference< PageData::Allocator > & rxAllocator, sal_uInt16 nPageSize)
+{
+    storeError result = PageData::Allocator::createInstance (rxAllocator, nPageSize);
+    if (result == store_E_None)
+    {
+        // @see readPageAt_Impl().
+        m_xAllocator = rxAllocator;
+    }
+    return result;
+}
+
+storeError MemoryLockBytes::readPageAt_Impl (std::shared_ptr<PageData> & rPage, sal_uInt32 nOffset)
+{
+    if (m_xAllocator.is())
+    {
+        std::shared_ptr<PageData> page (m_xAllocator->construct<PageData>(), PageData::Deallocate(m_xAllocator));
+        page.swap (rPage);
+    }
+
+    if (!m_xAllocator.is())
+        return store_E_InvalidAccess;
+    if (!rPage)
+        return store_E_OutOfMemory;
+
+    PageData * pagedata = rPage.get();
+    return readAt_Impl (nOffset, pagedata, pagedata->size());
+}
+
+storeError MemoryLockBytes::writePageAt_Impl (std::shared_ptr<PageData> const & rPage, sal_uInt32 nOffset)
+{
+    PageData const * pagedata = rPage.get();
+    OSL_PRECOND(!(pagedata == nullptr), "contract violation");
+    return writeAt_Impl (nOffset, pagedata, pagedata->size());
+}
+
+storeError MemoryLockBytes::readAt_Impl (sal_uInt32 nOffset, void * pBuffer, sal_uInt32 nBytes)
+{
+    sal_uInt8 const * src_lo = m_pData + nOffset;
+    if ((m_pData > src_lo) || (src_lo >= m_pData + m_nSize))
+        return store_E_NotExists;
+
+    sal_uInt8 const * src_hi = src_lo + nBytes;
+    if ((m_pData > src_hi) || (src_hi > m_pData + m_nSize))
+        return store_E_CantRead;
+
+    memcpy (pBuffer, src_lo, (src_hi - src_lo));
+    return store_E_None;
+}
+
+storeError MemoryLockBytes::writeAt_Impl (sal_uInt32 nOffset, const void * pBuffer, sal_uInt32 nBytes)
+{
+    sal_uInt64 const dst_size = nOffset + nBytes;
+    OSL_PRECOND(dst_size < SAL_MAX_UINT32, "store::ILockBytes::writeAt() contract violation");
+    if (dst_size > m_nSize)
+    {
+        storeError eErrCode = setSize_Impl (sal::static_int_cast<sal_uInt32>(dst_size));
+        if (eErrCode != store_E_None)
+            return eErrCode;
+    }
+    SAL_WARN_IF(dst_size > m_nSize, "store", "store::MemoryLockBytes::setSize_Impl() contract violation");
+
+    sal_uInt8 * dst_lo = m_pData + nOffset;
+    if (dst_lo >= m_pData + m_nSize)
+        return store_E_CantSeek;
+
+    sal_uInt8 * dst_hi = dst_lo + nBytes;
+    if (dst_hi > m_pData + m_nSize)
+        return store_E_CantWrite;
+
+    memcpy (dst_lo, pBuffer, (dst_hi - dst_lo));
+    return store_E_None;
+}
+
+storeError MemoryLockBytes::getSize_Impl (sal_uInt32 & rnSize)
+{
+    rnSize = m_nSize;
+    return store_E_None;
+}
+
+storeError MemoryLockBytes::setSize_Impl (sal_uInt32 nSize)
+{
+    if (nSize != m_nSize)
+    {
+        sal_uInt8 * pData = static_cast<sal_uInt8*>(std::realloc (m_pData, nSize));
+        if (pData != nullptr)
+        {
+            if (nSize > m_nSize)
+                memset (pData + m_nSize, 0, sal::static_int_cast<size_t>(nSize - m_nSize));
+        }
+        else
+        {
+            if (nSize != 0)
+                return store_E_OutOfMemory;
+        }
+        m_pData = pData;
+        m_nSize = nSize;
+    }
+    return store_E_None;
+}
+
+storeError MemoryLockBytes::flush_Impl()
+{
+    return store_E_None;
+}
+
+// ILockBytes factory implementations.
+
+namespace store
+{
+
+namespace {
+
+template< class T > struct ResourceHolder
+{
+    typedef typename T::destructor_type destructor_type;
+
+    T m_value;
+
+    explicit ResourceHolder (T const & value = T()) : m_value (value) {}
+    ~ResourceHolder() { reset(T()); }
+
+    T & get() { return m_value; }
+    T const & get() const { return m_value; }
+
+    void set (T const & value) { m_value = value; }
+    void reset (T const & value)
+    {
+        T tmp (m_value);
+        if (tmp != value)
+            destructor_type()(tmp);
+        set (value);
+    }
+    T release()
+    {
+        T tmp (m_value);
+        set (T());
+        return tmp;
+    }
+
+    ResourceHolder & operator= (ResourceHolder & rhs)
+    {
+        reset (rhs.release());
+        return *this;
+    }
+};
+
+}
+
+storeError
+FileLockBytes_createInstance (
+    rtl::Reference< ILockBytes > & rxLockBytes,
+    rtl_uString *                  pFilename,
+    storeAccessMode                eAccessMode
+)
+{
+    // Acquire file handle.
+    ResourceHolder<FileHandle> xFile;
+    storeError result = xFile.get().initialize (pFilename, eAccessMode);
+    if (result != store_E_None)
+        return result;
+
+    if (eAccessMode == storeAccessMode::ReadOnly)
+    {
+        ResourceHolder<FileMapping> xMapping;
+        if (xMapping.get().initialize (xFile.get().m_handle) == osl_File_E_None)
+        {
+            rxLockBytes = new MappedLockBytes (xMapping.get());
+            if (!rxLockBytes.is())
+                return store_E_OutOfMemory;
+            (void) xFile.release();
+            (void) xMapping.release();
+        }
+    }
+    if (!rxLockBytes.is())
+    {
+        rxLockBytes = new FileLockBytes (xFile.get());
+        if (!rxLockBytes.is())
+            return store_E_OutOfMemory;
+        (void) xFile.release();
+    }
+
+    return store_E_None;
+}
+
+storeError
+MemoryLockBytes_createInstance (
+    rtl::Reference< ILockBytes > & rxLockBytes
+)
+{
+    rxLockBytes = new MemoryLockBytes();
+    if (!rxLockBytes.is())
+        return store_E_OutOfMemory;
+
+    return store_E_None;
+}
+
+} // namespace store
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */