    /* -*- 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 <com/sun/star/lang/DisposedException.hpp>
    #include <cppuhelper/typeprovider.hxx>
    #include <cppuhelper/queryinterface.hxx>
    #include <osl/diagnose.h>
    #include <sal/log.hxx>

    #include "oseekinstream.hxx"
    #include "owriteablestream.hxx"

    using namespace ::com::sun::star;

    OInputSeekStream::OInputSeekStream( OWriteStream_Impl& pImpl,
                                        uno::Reference < io::XInputStream > const & xStream,
                                        const uno::Sequence< beans::PropertyValue >& aProps,
                                        sal_Int32 nStorageType )
    : OInputCompStream( pImpl, xStream, aProps, nStorageType )
    {
        m_xSeekable.set( m_xStream, uno::UNO_QUERY );
        OSL_ENSURE( m_xSeekable.is(), "No seeking support!" );
    }

    OInputSeekStream::OInputSeekStream( uno::Reference < io::XInputStream > const & xStream,
                                        const uno::Sequence< beans::PropertyValue >& aProps,
                                        sal_Int32 nStorageType )
    : OInputCompStream( xStream, aProps, nStorageType )
    {
        m_xSeekable.set( m_xStream, uno::UNO_QUERY );
        OSL_ENSURE( m_xSeekable.is(), "No seeking support!" );
    }

    OInputSeekStream::~OInputSeekStream()
    {
    }

    uno::Sequence< uno::Type > SAL_CALL OInputSeekStream::getTypes()
    {
        static ::cppu::OTypeCollection* pTypeCollection = nullptr ;

        if ( pTypeCollection == nullptr )
        {
            ::osl::MutexGuard aGuard( m_xMutex->GetMutex() ) ;

            if ( pTypeCollection == nullptr )
            {
                static ::cppu::OTypeCollection aTypeCollection(
                        cppu::UnoType<io::XSeekable>::get(),
                        OInputCompStream::getTypes() );

                pTypeCollection = &aTypeCollection ;
            }
        }

        return pTypeCollection->getTypes() ;
    }

    uno::Any SAL_CALL OInputSeekStream::queryInterface( const uno::Type& rType )
    {
        // Attention:
        //  Don't use mutex or guard in this method!!! Is a method of XInterface.

        uno::Any aReturn( ::cppu::queryInterface( rType,
                                               static_cast< io::XSeekable* >( this ) ) );

        if ( aReturn.hasValue() )
        {
            return aReturn ;
        }

        return OInputCompStream::queryInterface( rType ) ;
    }

    void SAL_CALL OInputSeekStream::acquire()
            throw()
    {
        OInputCompStream::acquire();
    }

    void SAL_CALL OInputSeekStream::release()
            throw()
    {
        OInputCompStream::release();
    }

    void SAL_CALL OInputSeekStream::seek( sal_Int64 location )
    {
        ::osl::MutexGuard aGuard( m_xMutex->GetMutex() );
        if ( m_bDisposed )
        {
            SAL_INFO("package.xstor", "Disposed!");
            throw lang::DisposedException();
        }

        if ( !m_xSeekable.is() )
        {
            SAL_INFO("package.xstor", "No seekable!");
            throw uno::RuntimeException();
        }

        m_xSeekable->seek( location );
    }

    sal_Int64 SAL_CALL OInputSeekStream::getPosition()
    {
        ::osl::MutexGuard aGuard( m_xMutex->GetMutex() );
        if ( m_bDisposed )
        {
            SAL_INFO("package.xstor", "Disposed!");
            throw lang::DisposedException();
        }

        if ( !m_xSeekable.is() )
        {
            SAL_INFO("package.xstor", "No seekable!");
            throw uno::RuntimeException();
        }

        return m_xSeekable->getPosition();
    }

    sal_Int64 SAL_CALL OInputSeekStream::getLength()
    {
        ::osl::MutexGuard aGuard( m_xMutex->GetMutex() );
        if ( m_bDisposed )
        {
            SAL_INFO("package.xstor", "Disposed!");
            throw lang::DisposedException();
        }

        if ( !m_xSeekable.is() )
        {
            SAL_INFO("package.xstor", "No seekable!");
            throw uno::RuntimeException();
        }

        return m_xSeekable->getLength();
    }

    /* vim:set shiftwidth=4 softtabstop=4 expandtab: */

↑ V547 Expression 'pTypeCollection == nullptr' is always true.