svl/source/misc/documentlockfile.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  *
   9  * This file incorporates work covered by the following license notice:
  10  *
  11  *   Licensed to the Apache Software Foundation (ASF) under one or more
  12  *   contributor license agreements. See the NOTICE file distributed
  13  *   with this work for additional information regarding copyright
  14  *   ownership. The ASF licenses this file to you under the Apache
  15  *   License, Version 2.0 (the "License"); you may not use this file
  16  *   except in compliance with the License. You may obtain a copy of
  17  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  18  */
  19
  20
  21 #include <com/sun/star/ucb/XCommandEnvironment.hpp>
  22 #include <com/sun/star/ucb/InsertCommandArgument.hpp>
  23 #include <com/sun/star/ucb/NameClashException.hpp>
  24 #include <com/sun/star/io/WrongFormatException.hpp>
  25 #include <com/sun/star/io/TempFile.hpp>
  26 #include <com/sun/star/io/XStream.hpp>
  27 #include <com/sun/star/io/XInputStream.hpp>
  28 #include <com/sun/star/io/XOutputStream.hpp>
  29 #include <com/sun/star/io/XSeekable.hpp>
  30 #include <com/sun/star/io/XTruncate.hpp>
  31
  32 #include <o3tl/enumrange.hxx>
  33
  34 #include <rtl/string.hxx>
  35 #include <rtl/ustring.hxx>
  36 #include <rtl/ustrbuf.hxx>
  37
  38 #include <comphelper/processfactory.hxx>
  39
  40 #include <ucbhelper/content.hxx>
  41
  42 #include <svl/documentlockfile.hxx>
  43
  44 using namespace ::com::sun::star;
  45
  46 namespace svt {
  47
  48 GenDocumentLockFile::GenDocumentLockFile(const OUString& aLockFileURL)
  49     : LockFileCommon(aLockFileURL)
  50 {
  51 }
  52
  53
  54 GenDocumentLockFile::~GenDocumentLockFile()
  55 {
  56 }
  57
  58 uno::Reference< io::XInputStream > GenDocumentLockFile::OpenStream(std::unique_lock<std::mutex>& /*rGuard*/)
  59 {
  60     uno::Reference < css::ucb::XCommandEnvironment > xEnv;
  61     ::ucbhelper::Content aSourceContent( GetURL(), xEnv, comphelper::getProcessComponentContext() );
  62
  63     // the file can be opened readonly, no locking will be done
  64     return aSourceContent.openStream();
  65 }
  66
  67 bool GenDocumentLockFile::CreateOwnLockFile()
  68 {
  69     std::unique_lock aGuard( m_aMutex );
  70
  71     try
  72     {
  73         uno::Reference< io::XStream > xTempFile(
  74             io::TempFile::create( comphelper::getProcessComponentContext() ),
  75             uno::UNO_QUERY_THROW );
  76         uno::Reference< io::XSeekable > xSeekable( xTempFile, uno::UNO_QUERY_THROW );
  77
  78         uno::Reference< io::XInputStream > xInput = xTempFile->getInputStream();
  79         uno::Reference< io::XOutputStream > xOutput = xTempFile->getOutputStream();
  80
  81         if ( !xInput.is() || !xOutput.is() )
  82             throw uno::RuntimeException();
  83
  84         LockFileEntry aNewEntry = GenerateOwnEntry();
  85         WriteEntryToStream( aGuard, aNewEntry, xOutput );
  86         xOutput->closeOutput();
  87
  88         xSeekable->seek( 0 );
  89
  90         uno::Reference < css::ucb::XCommandEnvironment > xEnv;
  91         ::ucbhelper::Content aTargetContent( GetURL(), xEnv, comphelper::getProcessComponentContext() );
  92
  93         ucb::InsertCommandArgument aInsertArg;
  94         aInsertArg.Data = std::move(xInput);
  95         aInsertArg.ReplaceExisting = false;
  96         uno::Any aCmdArg;
  97         aCmdArg <<= aInsertArg;
  98         aTargetContent.executeCommand( u"insert"_ustr, aCmdArg );
  99
 100         // try to let the file be hidden if possible
 101         try {
 102             aTargetContent.setPropertyValue(u"IsHidden"_ustr, uno::Any( true ) );
 103         } catch( uno::Exception& ) {}
 104     }
 105     catch( ucb::NameClashException& )
 106     {
 107         return false;
 108     }
 109
 110     return true;
 111 }
 112
 113 bool GenDocumentLockFile::OverwriteOwnLockFile()
 114 {
 115     std::unique_lock aGuard(m_aMutex);
 116
 117     // allows to overwrite the lock file with the current data
 118     try
 119     {
 120         uno::Reference < css::ucb::XCommandEnvironment > xEnv;
 121         ::ucbhelper::Content aTargetContent( GetURL(), xEnv, comphelper::getProcessComponentContext() );
 122
 123         LockFileEntry aNewEntry = GenerateOwnEntry();
 124
 125         uno::Reference< io::XStream > xStream = aTargetContent.openWriteableStreamNoLock();
 126         uno::Reference< io::XOutputStream > xOutput = xStream->getOutputStream();
 127         uno::Reference< io::XTruncate > xTruncate( xOutput, uno::UNO_QUERY_THROW );
 128
 129         xTruncate->truncate();
 130         WriteEntryToStream( aGuard, aNewEntry, xOutput );
 131         xOutput->closeOutput();
 132     }
 133     catch( uno::Exception& )
 134     {
 135         return false;
 136     }
 137
 138     return true;
 139 }
 140
 141 void GenDocumentLockFile::RemoveFile()
 142 {
 143     std::unique_lock aGuard( m_aMutex );
 144
 145     // TODO/LATER: the removing is not atomic, is it possible in general to make it atomic?
 146     LockFileEntry aNewEntry = GenerateOwnEntry();
 147     LockFileEntry aFileData = GetLockDataImpl(aGuard);
 148
 149     if ( aFileData[LockFileComponent::SYSUSERNAME] != aNewEntry[LockFileComponent::SYSUSERNAME]
 150       || aFileData[LockFileComponent::LOCALHOST] != aNewEntry[LockFileComponent::LOCALHOST]
 151       || aFileData[LockFileComponent::USERURL] != aNewEntry[LockFileComponent::USERURL] )
 152         throw io::IOException(); // not the owner, access denied
 153
 154     RemoveFileDirectly();
 155 }
 156
 157 void GenDocumentLockFile::RemoveFileDirectly()
 158 {
 159     uno::Reference < css::ucb::XCommandEnvironment > xEnv;
 160     ::ucbhelper::Content aCnt(GetURL(), xEnv, comphelper::getProcessComponentContext());
 161     aCnt.executeCommand(u"delete"_ustr,
 162         uno::Any(true));
 163 }
 164
 165 LockFileEntry GenDocumentLockFile::GetLockData()
 166 {
 167     std::unique_lock aGuard(m_aMutex);
 168     return GetLockDataImpl(aGuard);
 169 }
 170
 171 DocumentLockFile::DocumentLockFile( std::u16string_view aOrigURL )
 172     : GenDocumentLockFile(GenerateOwnLockFileURL(aOrigURL, u".~lock."))
 173 {
 174 }
 175
 176
 177 DocumentLockFile::~DocumentLockFile()
 178 {
 179 }
 180
 181
 182 void DocumentLockFile::WriteEntryToStream(
 183     std::unique_lock<std::mutex>& /*rGuard*/,
 184     const LockFileEntry& aEntry, const uno::Reference< io::XOutputStream >& xOutput )
 185 {
 186     OUStringBuffer aBuffer(256);
 187
 188     for ( LockFileComponent lft : o3tl::enumrange<LockFileComponent>() )
 189     {
 190         aBuffer.append( EscapeCharacters( aEntry[lft] ) );
 191         if ( lft < LockFileComponent::LAST )
 192             aBuffer.append( ',' );
 193         else
 194             aBuffer.append( ';' );
 195     }
 196
 197     OString aStringData( OUStringToOString( aBuffer, RTL_TEXTENCODING_UTF8 ) );
 198     uno::Sequence< sal_Int8 > aData( reinterpret_cast<sal_Int8 const *>(aStringData.getStr()), aStringData.getLength() );
 199     xOutput->writeBytes( aData );
 200 }
 201
 202 LockFileEntry DocumentLockFile::GetLockDataImpl(std::unique_lock<std::mutex>& rGuard)
 203 {
 204     uno::Reference< io::XInputStream > xInput = OpenStream(rGuard);
 205     if ( !xInput.is() )
 206         throw uno::RuntimeException();
 207
 208     const sal_Int32 nBufLen = 32000;
 209     uno::Sequence< sal_Int8 > aBuffer( nBufLen );
 210
 211     sal_Int32 nRead = xInput->readBytes( aBuffer, nBufLen );
 212     xInput->closeInput();
 213
 214     if ( nRead == nBufLen )
 215         throw io::WrongFormatException();
 216
 217     sal_Int32 nCurPos = 0;
 218     return ParseEntry( aBuffer, nCurPos );
 219 }
 220
 221
 222
 223
 224 } // namespace svt
 225
 226 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */