desktop/source/deployment/dp_persmap.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.
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   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 #include "dp_misc.h"
  21 #include "dp_persmap.h"
  22 #include "rtl/strbuf.hxx"
  23
  24 #ifndef DISABLE_BDB2PMAP
  25 #  include <vector>
  26 #endif
  27
  28 using namespace ::rtl;
  29
  30 // the persistent map is used to manage a handful of key-value string pairs
  31 // this implementation replaces a rather heavy-weight berkeleydb integration
  32
  33 // the file backing up a persistent map consists of line pairs with
  34 // - a key string   (encoded with chars 0x00..0x0F being escaped)
  35 // - a value string (encoded with chars 0x00..0x0F being escaped)
  36
  37 namespace dp_misc
  38 {
  39
  40 static const char PmapMagic[4] = {'P','m','p','1'};
  41
  42 PersistentMap::PersistentMap( OUString const & url_, bool readOnly )
  43 :    m_MapFile( expandUnoRcUrl(url_) )
  44 ,    m_bReadOnly( readOnly )
  45 ,    m_bIsOpen( false )
  46 ,    m_bToBeCreated( !readOnly )
  47 ,    m_bIsDirty( false )
  48 {
  49 #ifndef DISABLE_BDB2PMAP
  50     m_MapFileName = expandUnoRcUrl( url_ );
  51 #endif
  52     open();
  53 }
  54
  55 PersistentMap::PersistentMap()
  56 :    m_MapFile( OUString() )
  57 ,    m_bReadOnly( false )
  58 ,    m_bIsOpen( false )
  59 ,    m_bToBeCreated( false )
  60 ,    m_bIsDirty( false )
  61 {}
  62
  63 PersistentMap::~PersistentMap()
  64 {
  65     if( m_bIsDirty )
  66         flush();
  67     if( m_bIsOpen )
  68         m_MapFile.close();
  69 }
  70
  71
  72 // replace 0x00..0x0F with "%0".."%F"
  73 // replace "%" with "%%"
  74 static OString encodeString( const OString& rStr)
  75 {
  76     const sal_Char* pChar = rStr.getStr();
  77     const sal_Int32 nLen = rStr.getLength();
  78     sal_Int32 i = nLen;
  79     // short circuit for the simple non-encoded case
  80     while( --i >= 0)
  81     {
  82         const unsigned char c = (unsigned char) *(pChar++);
  83         if( c <= 0x0F )
  84             break;
  85         if( c == '%')
  86             break;
  87     }
  88     if( i < 0)
  89         return rStr;
  90
  91     // escape chars 0x00..0x0F with "%0".."%F"
  92     OStringBuffer aEncStr( nLen + 32);
  93     aEncStr.append( pChar - (nLen-i), nLen - i);
  94     while( --i >= 0)
  95     {
  96         unsigned char c = (unsigned char) *(pChar++);
  97         if( c <= 0x0F )
  98         {
  99             aEncStr.append( '%');
 100             c += (c <= 0x09) ? '0' : 'A'-10;
 101         } else if( c == '%')
 102             aEncStr.append( '%');
 103         aEncStr.append( c);
 104     }
 105
 106     return aEncStr.makeStringAndClear();
 107 }
 108
 109 // replace "%0".."%F" with 0x00..0x0F
 110 // replace "%%" with "%"
 111 static OString decodeString( const sal_Char* pEncChars, int nLen)
 112 {
 113     const char* pChar = pEncChars;
 114     sal_Int32 i = nLen;
 115     // short circuit for the simple non-encoded case
 116     while( --i >= 0)
 117         if( *(pChar++) == '%')
 118             break;
 119     if( i < 0)
 120         return OString( pEncChars, nLen);
 121
 122     // replace escaped chars with their decoded counterparts
 123     OStringBuffer aDecStr( nLen);
 124     pChar = pEncChars;
 125     for( i = nLen; --i >= 0;)
 126     {
 127         sal_Char c = *(pChar++);
 128         // handle escaped character
 129         if( c == '%')
 130         {
 131             --i;
 132             OSL_ASSERT( i >= 0);
 133             c = *(pChar++);
 134             if( ('0' <= c) && (c <= '9'))
 135                 c -= '0';
 136             else
 137             {
 138                 OSL_ASSERT( ('A' <= c) && (c <= 'F'));
 139                 c -= ('A'-10);
 140             }
 141         }
 142         aDecStr.append( c);
 143     }
 144
 145     return aDecStr.makeStringAndClear();
 146 }
 147
 148 bool PersistentMap::open()
 149 {
 150     // open the existing file
 151     sal_uInt32 nOpenFlags = osl_File_OpenFlag_Read;
 152     if( !m_bReadOnly)
 153         nOpenFlags |= osl_File_OpenFlag_Write;
 154
 155     const osl::File::RC rcOpen = m_MapFile.open( nOpenFlags);
 156     m_bIsOpen = (rcOpen == osl::File::E_None);
 157
 158     // or create later if needed
 159     m_bToBeCreated &= (rcOpen == osl::File::E_NOENT) && !m_bIsOpen;
 160
 161 #ifndef DISABLE_BDB2PMAP
 162     if( m_bToBeCreated )
 163         importFromBDB();
 164 #endif
 165
 166     if( !m_bIsOpen)
 167         return m_bToBeCreated;
 168
 169     return readAll();
 170 }
 171
 172 //______________________________________________________________________________
 173 bool PersistentMap::readAll()
 174 {
 175     // prepare for re-reading the map-file
 176     const osl::FileBase::RC nRes = m_MapFile.setPos( osl_Pos_Absolut, 0);
 177     (void)nRes;
 178     m_entries.clear();
 179
 180     // read header and check magic
 181     char aHeaderBytes[ sizeof(PmapMagic)];
 182     sal_uInt64 nBytesRead = 0;
 183     m_MapFile.read( aHeaderBytes, sizeof(aHeaderBytes), nBytesRead);
 184     OSL_ASSERT( nBytesRead == sizeof(aHeaderBytes));
 185     if( nBytesRead != sizeof(aHeaderBytes))
 186         return false;
 187     // check header magic
 188     for( int i = 0; i < (int)sizeof(PmapMagic); ++i)
 189         if( aHeaderBytes[i] != PmapMagic[i])
 190             return false;
 191
 192     // read key value pairs and add them to the map
 193     ByteSequence aKeyLine;
 194     ByteSequence aValLine;
 195     for(;;)
 196     {
 197         // read key-value line pair
 198         // an empty key name indicates the end of the line pairs
 199         if( m_MapFile.readLine( aKeyLine) != osl::File::E_None)
 200             return false;
 201         if( !aKeyLine.getLength())
 202             break;
 203         if( m_MapFile.readLine( aValLine) != osl::File::E_None)
 204             return false;
 205         // decode key and value strings
 206         const OString aKeyName = decodeString( (sal_Char*)aKeyLine.getConstArray(), aKeyLine.getLength());
 207         const OString aValName = decodeString( (sal_Char*)aValLine.getConstArray(), aValLine.getLength());
 208         // insert key-value pair into map
 209         add( aKeyName, aValName );
 210         // check end-of-file status
 211         sal_Bool bIsEOF = true;
 212         if( m_MapFile.isEndOfFile( &bIsEOF) != osl::File::E_None )
 213             return false;
 214         if( bIsEOF )
 215             break;
 216     }
 217
 218     m_bIsDirty = false;
 219     return true;
 220 }
 221
 222 void PersistentMap::flush()
 223 {
 224     if( !m_bIsDirty)
 225         return;
 226     OSL_ASSERT( !m_bReadOnly);
 227     if( m_bToBeCreated && !m_entries.empty())
 228     {
 229         const sal_uInt32 nOpenFlags = osl_File_OpenFlag_Read | osl_File_OpenFlag_Write | osl_File_OpenFlag_Create;
 230         const osl::File::RC rcOpen = m_MapFile.open( nOpenFlags);
 231         m_bIsOpen = (rcOpen == osl::File::E_None);
 232         m_bToBeCreated = !m_bIsOpen;
 233     }
 234     if( !m_bIsOpen)
 235         return;
 236
 237     // write header magic
 238     const osl::FileBase::RC nRes = m_MapFile.setPos( osl_Pos_Absolut, 0);
 239     (void)nRes;
 240     sal_uInt64 nBytesWritten = 0;
 241     m_MapFile.write( PmapMagic, sizeof(PmapMagic), nBytesWritten);
 242
 243     // write key value pairs
 244     t_string2string_map::const_iterator it = m_entries.begin();
 245     for(; it != m_entries.end(); ++it) {
 246         // write line for key
 247         const OString aKeyString = encodeString( (*it).first);
 248         const sal_Int32 nKeyLen = aKeyString.getLength();
 249         m_MapFile.write( aKeyString.getStr(), nKeyLen, nBytesWritten);
 250         OSL_ASSERT( nKeyLen == (sal_Int32)nBytesWritten);
 251         m_MapFile.write( "\n", 1, nBytesWritten);
 252         // write line for value
 253         const OString& rValString = encodeString( (*it).second);
 254         const sal_Int32 nValLen = rValString.getLength();
 255         m_MapFile.write( rValString.getStr(), nValLen, nBytesWritten);
 256         OSL_ASSERT( nValLen == (sal_Int32)nBytesWritten);
 257         m_MapFile.write( "\n", 1, nBytesWritten);
 258     }
 259
 260     // write a file delimiter (an empty key-string)
 261     m_MapFile.write( "\n", 1, nBytesWritten);
 262     // truncate file here
 263     sal_uInt64 nNewFileSize;
 264     if( m_MapFile.getPos( nNewFileSize) == osl::File::E_None)
 265         m_MapFile.setSize( nNewFileSize);
 266     // flush to disk
 267     m_MapFile.sync();
 268     // the in-memory map now matches to the file on disk
 269     m_bIsDirty = false;
 270 }
 271
 272 bool PersistentMap::has( OString const & key ) const
 273 {
 274     return get( NULL, key );
 275 }
 276
 277 bool PersistentMap::get( OString * value, OString const & key ) const
 278 {
 279     t_string2string_map::const_iterator it = m_entries.find( key);
 280     if( it == m_entries.end())
 281         return false;
 282     if( value)
 283         *value = it->second;
 284     return true;
 285 }
 286
 287 void PersistentMap::add( OString const & key, OString const & value )
 288 {
 289     if( m_bReadOnly)
 290         return;
 291     typedef std::pair<t_string2string_map::iterator,bool> InsertRC;
 292     InsertRC r = m_entries.insert( t_string2string_map::value_type(key,value));
 293     m_bIsDirty = r.second;
 294 }
 295
 296 //______________________________________________________________________________
 297 void PersistentMap::put( OString const & key, OString const & value )
 298 {
 299     add( key, value);
 300     // HACK: flush now as the extension manager does not seem
 301     //       to properly destruct this object in some situations
 302     if(m_bIsDirty)
 303         flush();
 304 }
 305
 306 bool PersistentMap::erase( OString const & key, bool flush_immediately )
 307 {
 308     if( m_bReadOnly)
 309         return false;
 310     size_t nCount = m_entries.erase( key);
 311     if( !nCount)
 312         return false;
 313     m_bIsDirty = true;
 314     if( flush_immediately)
 315         flush();
 316     return true;
 317 }
 318
 319 t_string2string_map PersistentMap::getEntries() const
 320 {
 321     // TODO: return by const reference instead?
 322     return m_entries;
 323 }
 324
 325 #ifndef DISABLE_BDB2PMAP
 326 bool PersistentMap::importFromBDB()
 327 {
 328     if( m_bReadOnly)
 329         return false;
 330
 331     // get the name of its BDB counterpart
 332     OUString aDBName = m_MapFileName;
 333     if( !aDBName.endsWith( ".pmap" ))
 334         return false;
 335     aDBName = aDBName.replaceAt( aDBName.getLength()-5, 5, ".db");
 336
 337     // open the corresponding BDB file for reading
 338     osl::File aDBFile( aDBName);
 339     osl::File::RC rc = aDBFile.open( osl_File_OpenFlag_Read);
 340     if( rc != osl::File::E_None)
 341         return false;
 342     sal_uInt64 nFileSize = 0;
 343     if( aDBFile.getSize( nFileSize) != osl::File::E_None)
 344         return false;
 345
 346     // read the BDB file
 347     std::vector<sal_uInt8> aRawBDB( nFileSize);
 348     for( sal_uInt64 nOfs = 0; nOfs < nFileSize;) {
 349         sal_uInt64 nBytesRead = 0;
 350         rc = aDBFile.read( (void*)&aRawBDB[nOfs], nFileSize - nOfs, nBytesRead);
 351         if( (rc != osl::File::E_None) || !nBytesRead)
 352             return false;
 353         nOfs += nBytesRead;
 354     }
 355
 356     // check BDB file header for non_encrypted Hash format v4..9
 357     if( nFileSize < 0x0100)
 358         return false;
 359     if( aRawBDB[24] != 0) // only not-encrypted migration
 360         return false;
 361     if( aRawBDB[25] != 8) // we expect a P_HASHMETA page
 362         return false;
 363     const bool bLE = (aRawBDB[12]==0x61 && aRawBDB[13]==0x15 && aRawBDB[14]==0x06);
 364     const bool bBE = (aRawBDB[15]==0x61 && aRawBDB[14]==0x15 && aRawBDB[13]==0x06);
 365     if( bBE == bLE)
 366         return false;
 367     if( (aRawBDB[16] < 4) || (9 < aRawBDB[16])) // version
 368         return false;
 369     const sal_uInt64 nPgSize = bLE
 370     ?    (aRawBDB[20] + (aRawBDB[21]<<8) + (aRawBDB[22]<<16) + (aRawBDB[23]<<24))
 371     :    (aRawBDB[23] + (aRawBDB[22]<<8) + (aRawBDB[21]<<16) + (aRawBDB[20]<<24));
 372     const int nPgCount = nFileSize / nPgSize;
 373     if( nPgCount * nPgSize != nFileSize)
 374         return false;
 375
 376     // find PackageManager's new_style entries
 377     // using a simple heuristic for BDB_Hash pages
 378     int nEntryCount = 0;
 379     for( int nPgNo = 1; nPgNo < nPgCount; ++nPgNo) {
 380         // parse the next _db_page
 381         const sal_uInt8* const pPage = &aRawBDB[ nPgNo * nPgSize];
 382         const sal_uInt8* const pEnd = pPage + nPgSize;
 383         const int nHfOffset = bLE ? (pPage[22] + (pPage[23]<<8)) : (pPage[23] + (pPage[22]<<8));
 384         if( nHfOffset <= 0)
 385             continue;
 386         const sal_uInt8* pCur = pPage + nHfOffset;
 387         // iterate through the entries
 388         for(; pCur < pEnd; ++pCur) {
 389             if( pCur[0] != 0x01)
 390                 continue;
 391             // get the value-candidate
 392             const sal_uInt8* pVal = pCur + 1;
 393             while( ++pCur < pEnd)
 394                 if( (*pCur < ' ') || ((*pCur > 0x7F) && (*pCur != 0xFF)))
 395                     break;
 396             if( pCur >= pEnd)
 397                 break;
 398             if( (pCur[0] != 0x01) || (pCur[1] != 0xFF))
 399                 continue;
 400             const OString aVal( (sal_Char*)pVal, pCur - pVal);
 401             // get the key-candidate
 402             const sal_uInt8* pKey = pCur + 1;
 403             while( ++pCur < pEnd)
 404                 if( (*pCur < ' ') || ((*pCur > 0x7F) && (*pCur != 0xFF)))
 405                     break;
 406             if( (pCur < pEnd) && (*pCur > 0x01))
 407                 continue;
 408             const OString aKey( (sal_Char*)pKey, pCur - pKey);
 409             --pCur; // prepare for next round by rewinding to end of key-string
 410
 411             // add the key/value pair
 412             add( aKey, aVal);
 413             ++nEntryCount;
 414         }
 415     }
 416
 417     return (nEntryCount > 0);
 418 }
 419 #endif // DISABLE_BDB2PMAP
 420
 421 }
 422
 423 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */