includes/db/DatabaseSqlite.php

   1 <?php
   2 /**
   3  * This is the SQLite database abstraction layer.
   4  * See maintenance/sqlite/README for development notes and other specific information
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  19  * http://www.gnu.org/copyleft/gpl.html
  20  *
  21  * @file
  22  * @ingroup Database
  23  */
  24
  25 /**
  26  * @ingroup Database
  27  */
  28 class DatabaseSqlite extends Database {
  29         /** @var bool Whether full text is enabled */
  30         private static $fulltextEnabled = null;
  31
  32         /** @var string Directory */
  33         protected $dbDir;
  34
  35         /** @var string File name for SQLite database file */
  36         protected $dbPath;
  37
  38         /** @var string Transaction mode */
  39         protected $trxMode;
  40
  41         /** @var int The number of rows affected as an integer */
  42         protected $mAffectedRows;
  43
  44         /** @var resource */
  45         protected $mLastResult;
  46
  47         /** @var PDO */
  48         protected $mConn;
  49
  50         /** @var FSLockManager (hopefully on the same server as the DB) */
  51         protected $lockMgr;
  52
  53         /**
  54          * Additional params include:
  55          *   - dbDirectory : directory containing the DB and the lock file directory
  56          *                   [defaults to $wgSQLiteDataDir]
  57          *   - dbFilePath  : use this to force the path of the DB file
  58          *   - trxMode     : one of (deferred, immediate, exclusive)
  59          * @param array $p
  60          */
  61         function __construct( array $p ) {
  62                 global $wgSharedDB, $wgSQLiteDataDir;
  63
  64                 $this->dbDir = isset( $p['dbDirectory'] ) ? $p['dbDirectory'] : $wgSQLiteDataDir;
  65
  66                 if ( isset( $p['dbFilePath'] ) ) {
  67                         parent::__construct( $p );
  68                         // Standalone .sqlite file mode.
  69                         // Super doesn't open when $user is false, but we can work with $dbName,
  70                         // which is derived from the file path in this case.
  71                         $this->openFile( $p['dbFilePath'] );
  72                 } else {
  73                         $this->mDBname = $p['dbname'];
  74                         // Stock wiki mode using standard file names per DB.
  75                         parent::__construct( $p );
  76                         // Super doesn't open when $user is false, but we can work with $dbName
  77                         if ( $p['dbname'] && !$this->isOpen() ) {
  78                                 if ( $this->open( $p['host'], $p['user'], $p['password'], $p['dbname'] ) ) {
  79                                         if ( $wgSharedDB ) {
  80                                                 $this->attachDatabase( $wgSharedDB );
  81                                         }
  82                                 }
  83                         }
  84                 }
  85
  86                 $this->trxMode = isset( $p['trxMode'] ) ? strtoupper( $p['trxMode'] ) : null;
  87                 if ( $this->trxMode &&
  88                         !in_array( $this->trxMode, [ 'DEFERRED', 'IMMEDIATE', 'EXCLUSIVE' ] )
  89                 ) {
  90                         $this->trxMode = null;
  91                         wfWarn( "Invalid SQLite transaction mode provided." );
  92                 }
  93
  94                 $this->lockMgr = new FSLockManager( [ 'lockDirectory' => "{$this->dbDir}/locks" ] );
  95         }
  96
  97         /**
  98          * @param string $filename
  99          * @param array $p Options map; supports:
 100          *   - flags       : (same as __construct counterpart)
 101          *   - trxMode     : (same as __construct counterpart)
 102          *   - dbDirectory : (same as __construct counterpart)
 103          * @return DatabaseSqlite
 104          * @since 1.25
 105          */
 106         public static function newStandaloneInstance( $filename, array $p = [] ) {
 107                 $p['dbFilePath'] = $filename;
 108                 $p['schema'] = false;
 109                 $p['tablePrefix'] = '';
 110
 111                 return DatabaseBase::factory( 'sqlite', $p );
 112         }
 113
 114         /**
 115          * @return string
 116          */
 117         function getType() {
 118                 return 'sqlite';
 119         }
 120
 121         /**
 122          * @todo Check if it should be true like parent class
 123          *
 124          * @return bool
 125          */
 126         function implicitGroupby() {
 127                 return false;
 128         }
 129
 130         /** Open an SQLite database and return a resource handle to it
 131          *  NOTE: only $dbName is used, the other parameters are irrelevant for SQLite databases
 132          *
 133          * @param string $server
 134          * @param string $user
 135          * @param string $pass
 136          * @param string $dbName
 137          *
 138          * @throws DBConnectionError
 139          * @return PDO
 140          */
 141         function open( $server, $user, $pass, $dbName ) {
 142                 $this->close();
 143                 $fileName = self::generateFileName( $this->dbDir, $dbName );
 144                 if ( !is_readable( $fileName ) ) {
 145                         $this->mConn = false;
 146                         throw new DBConnectionError( $this, "SQLite database not accessible" );
 147                 }
 148                 $this->openFile( $fileName );
 149
 150                 return $this->mConn;
 151         }
 152
 153         /**
 154          * Opens a database file
 155          *
 156          * @param string $fileName
 157          * @throws DBConnectionError
 158          * @return PDO|bool SQL connection or false if failed
 159          */
 160         protected function openFile( $fileName ) {
 161                 $err = false;
 162
 163                 $this->dbPath = $fileName;
 164                 try {
 165                         if ( $this->mFlags & DBO_PERSISTENT ) {
 166                                 $this->mConn = new PDO( "sqlite:$fileName", '', '',
 167                                         [ PDO::ATTR_PERSISTENT => true ] );
 168                         } else {
 169                                 $this->mConn = new PDO( "sqlite:$fileName", '', '' );
 170                         }
 171                 } catch ( PDOException $e ) {
 172                         $err = $e->getMessage();
 173                 }
 174
 175                 if ( !$this->mConn ) {
 176                         wfDebug( "DB connection error: $err\n" );
 177                         throw new DBConnectionError( $this, $err );
 178                 }
 179
 180                 $this->mOpened = !!$this->mConn;
 181                 if ( $this->mOpened ) {
 182                         # Set error codes only, don't raise exceptions
 183                         $this->mConn->setAttribute( PDO::ATTR_ERRMODE, PDO::ERRMODE_SILENT );
 184                         # Enforce LIKE to be case sensitive, just like MySQL
 185                         $this->query( 'PRAGMA case_sensitive_like = 1' );
 186
 187                         return $this->mConn;
 188                 }
 189
 190                 return false;
 191         }
 192
 193         /**
 194          * @return string SQLite DB file path
 195          * @since 1.25
 196          */
 197         public function getDbFilePath() {
 198                 return $this->dbPath;
 199         }
 200
 201         /**
 202          * Does not actually close the connection, just destroys the reference for GC to do its work
 203          * @return bool
 204          */
 205         protected function closeConnection() {
 206                 $this->mConn = null;
 207
 208                 return true;
 209         }
 210
 211         /**
 212          * Generates a database file name. Explicitly public for installer.
 213          * @param string $dir Directory where database resides
 214          * @param string $dbName Database name
 215          * @return string
 216          */
 217         public static function generateFileName( $dir, $dbName ) {
 218                 return "$dir/$dbName.sqlite";
 219         }
 220
 221         /**
 222          * Check if the searchindext table is FTS enabled.
 223          * @return bool False if not enabled.
 224          */
 225         function checkForEnabledSearch() {
 226                 if ( self::$fulltextEnabled === null ) {
 227                         self::$fulltextEnabled = false;
 228                         $table = $this->tableName( 'searchindex' );
 229                         $res = $this->query( "SELECT sql FROM sqlite_master WHERE tbl_name = '$table'", __METHOD__ );
 230                         if ( $res ) {
 231                                 $row = $res->fetchRow();
 232                                 self::$fulltextEnabled = stristr( $row['sql'], 'fts' ) !== false;
 233                         }
 234                 }
 235
 236                 return self::$fulltextEnabled;
 237         }
 238
 239         /**
 240          * Returns version of currently supported SQLite fulltext search module or false if none present.
 241          * @return string
 242          */
 243         static function getFulltextSearchModule() {
 244                 static $cachedResult = null;
 245                 if ( $cachedResult !== null ) {
 246                         return $cachedResult;
 247                 }
 248                 $cachedResult = false;
 249                 $table = 'dummy_search_test';
 250
 251                 $db = self::newStandaloneInstance( ':memory:' );
 252                 if ( $db->query( "CREATE VIRTUAL TABLE $table USING FTS3(dummy_field)", __METHOD__, true ) ) {
 253                         $cachedResult = 'FTS3';
 254                 }
 255                 $db->close();
 256
 257                 return $cachedResult;
 258         }
 259
 260         /**
 261          * Attaches external database to our connection, see http://sqlite.org/lang_attach.html
 262          * for details.
 263          *
 264          * @param string $name Database name to be used in queries like
 265          *   SELECT foo FROM dbname.table
 266          * @param bool|string $file Database file name. If omitted, will be generated
 267          *   using $name and configured data directory
 268          * @param string $fname Calling function name
 269          * @return ResultWrapper
 270          */
 271         function attachDatabase( $name, $file = false, $fname = __METHOD__ ) {
 272                 if ( !$file ) {
 273                         $file = self::generateFileName( $this->dbDir, $name );
 274                 }
 275                 $file = $this->addQuotes( $file );
 276
 277                 return $this->query( "ATTACH DATABASE $file AS $name", $fname );
 278         }
 279
 280         /**
 281          * @see DatabaseBase::isWriteQuery()
 282          *
 283          * @param string $sql
 284          * @return bool
 285          */
 286         function isWriteQuery( $sql ) {
 287                 return parent::isWriteQuery( $sql ) && !preg_match( '/^(ATTACH|PRAGMA)\b/i', $sql );
 288         }
 289
 290         /**
 291          * SQLite doesn't allow buffered results or data seeking etc, so we'll use fetchAll as the result
 292          *
 293          * @param string $sql
 294          * @return bool|ResultWrapper
 295          */
 296         protected function doQuery( $sql ) {
 297                 $res = $this->mConn->query( $sql );
 298                 if ( $res === false ) {
 299                         return false;
 300                 } else {
 301                         $r = $res instanceof ResultWrapper ? $res->result : $res;
 302                         $this->mAffectedRows = $r->rowCount();
 303                         $res = new ResultWrapper( $this, $r->fetchAll() );
 304                 }
 305
 306                 return $res;
 307         }
 308
 309         /**
 310          * @param ResultWrapper|mixed $res
 311          */
 312         function freeResult( $res ) {
 313                 if ( $res instanceof ResultWrapper ) {
 314                         $res->result = null;
 315                 } else {
 316                         $res = null;
 317                 }
 318         }
 319
 320         /**
 321          * @param ResultWrapper|array $res
 322          * @return stdClass|bool
 323          */
 324         function fetchObject( $res ) {
 325                 if ( $res instanceof ResultWrapper ) {
 326                         $r =& $res->result;
 327                 } else {
 328                         $r =& $res;
 329                 }
 330
 331                 $cur = current( $r );
 332                 if ( is_array( $cur ) ) {
 333                         next( $r );
 334                         $obj = new stdClass;
 335                         foreach ( $cur as $k => $v ) {
 336                                 if ( !is_numeric( $k ) ) {
 337                                         $obj->$k = $v;
 338                                 }
 339                         }
 340
 341                         return $obj;
 342                 }
 343
 344                 return false;
 345         }
 346
 347         /**
 348          * @param ResultWrapper|mixed $res
 349          * @return array|bool
 350          */
 351         function fetchRow( $res ) {
 352                 if ( $res instanceof ResultWrapper ) {
 353                         $r =& $res->result;
 354                 } else {
 355                         $r =& $res;
 356                 }
 357                 $cur = current( $r );
 358                 if ( is_array( $cur ) ) {
 359                         next( $r );
 360
 361                         return $cur;
 362                 }
 363
 364                 return false;
 365         }
 366
 367         /**
 368          * The PDO::Statement class implements the array interface so count() will work
 369          *
 370          * @param ResultWrapper|array $res
 371          * @return int
 372          */
 373         function numRows( $res ) {
 374                 $r = $res instanceof ResultWrapper ? $res->result : $res;
 375
 376                 return count( $r );
 377         }
 378
 379         /**
 380          * @param ResultWrapper $res
 381          * @return int
 382          */
 383         function numFields( $res ) {
 384                 $r = $res instanceof ResultWrapper ? $res->result : $res;
 385                 if ( is_array( $r ) && count( $r ) > 0 ) {
 386                         // The size of the result array is twice the number of fields. (Bug: 65578)
 387                         return count( $r[0] ) / 2;
 388                 } else {
 389                         // If the result is empty return 0
 390                         return 0;
 391                 }
 392         }
 393
 394         /**
 395          * @param ResultWrapper $res
 396          * @param int $n
 397          * @return bool
 398          */
 399         function fieldName( $res, $n ) {
 400                 $r = $res instanceof ResultWrapper ? $res->result : $res;
 401                 if ( is_array( $r ) ) {
 402                         $keys = array_keys( $r[0] );
 403
 404                         return $keys[$n];
 405                 }
 406
 407                 return false;
 408         }
 409
 410         /**
 411          * Use MySQL's naming (accounts for prefix etc) but remove surrounding backticks
 412          *
 413          * @param string $name
 414          * @param string $format
 415          * @return string
 416          */
 417         function tableName( $name, $format = 'quoted' ) {
 418                 // table names starting with sqlite_ are reserved
 419                 if ( strpos( $name, 'sqlite_' ) === 0 ) {
 420                         return $name;
 421                 }
 422
 423                 return str_replace( '"', '', parent::tableName( $name, $format ) );
 424         }
 425
 426         /**
 427          * Index names have DB scope
 428          *
 429          * @param string $index
 430          * @return string
 431          */
 432         protected function indexName( $index ) {
 433                 return $index;
 434         }
 435
 436         /**
 437          * This must be called after nextSequenceVal
 438          *
 439          * @return int
 440          */
 441         function insertId() {
 442                 // PDO::lastInsertId yields a string :(
 443                 return intval( $this->mConn->lastInsertId() );
 444         }
 445
 446         /**
 447          * @param ResultWrapper|array $res
 448          * @param int $row
 449          */
 450         function dataSeek( $res, $row ) {
 451                 if ( $res instanceof ResultWrapper ) {
 452                         $r =& $res->result;
 453                 } else {
 454                         $r =& $res;
 455                 }
 456                 reset( $r );
 457                 if ( $row > 0 ) {
 458                         for ( $i = 0; $i < $row; $i++ ) {
 459                                 next( $r );
 460                         }
 461                 }
 462         }
 463
 464         /**
 465          * @return string
 466          */
 467         function lastError() {
 468                 if ( !is_object( $this->mConn ) ) {
 469                         return "Cannot return last error, no db connection";
 470                 }
 471                 $e = $this->mConn->errorInfo();
 472
 473                 return isset( $e[2] ) ? $e[2] : '';
 474         }
 475
 476         /**
 477          * @return string
 478          */
 479         function lastErrno() {
 480                 if ( !is_object( $this->mConn ) ) {
 481                         return "Cannot return last error, no db connection";
 482                 } else {
 483                         $info = $this->mConn->errorInfo();
 484
 485                         return $info[1];
 486                 }
 487         }
 488
 489         /**
 490          * @return int
 491          */
 492         function affectedRows() {
 493                 return $this->mAffectedRows;
 494         }
 495
 496         /**
 497          * Returns information about an index
 498          * Returns false if the index does not exist
 499          * - if errors are explicitly ignored, returns NULL on failure
 500          *
 501          * @param string $table
 502          * @param string $index
 503          * @param string $fname
 504          * @return array
 505          */
 506         function indexInfo( $table, $index, $fname = __METHOD__ ) {
 507                 $sql = 'PRAGMA index_info(' . $this->addQuotes( $this->indexName( $index ) ) . ')';
 508                 $res = $this->query( $sql, $fname );
 509                 if ( !$res ) {
 510                         return null;
 511                 }
 512                 if ( $res->numRows() == 0 ) {
 513                         return false;
 514                 }
 515                 $info = [];
 516                 foreach ( $res as $row ) {
 517                         $info[] = $row->name;
 518                 }
 519
 520                 return $info;
 521         }
 522
 523         /**
 524          * @param string $table
 525          * @param string $index
 526          * @param string $fname
 527          * @return bool|null
 528          */
 529         function indexUnique( $table, $index, $fname = __METHOD__ ) {
 530                 $row = $this->selectRow( 'sqlite_master', '*',
 531                         [
 532                                 'type' => 'index',
 533                                 'name' => $this->indexName( $index ),
 534                         ], $fname );
 535                 if ( !$row || !isset( $row->sql ) ) {
 536                         return null;
 537                 }
 538
 539                 // $row->sql will be of the form CREATE [UNIQUE] INDEX ...
 540                 $indexPos = strpos( $row->sql, 'INDEX' );
 541                 if ( $indexPos === false ) {
 542                         return null;
 543                 }
 544                 $firstPart = substr( $row->sql, 0, $indexPos );
 545                 $options = explode( ' ', $firstPart );
 546
 547                 return in_array( 'UNIQUE', $options );
 548         }
 549
 550         /**
 551          * Filter the options used in SELECT statements
 552          *
 553          * @param array $options
 554          * @return array
 555          */
 556         function makeSelectOptions( $options ) {
 557                 foreach ( $options as $k => $v ) {
 558                         if ( is_numeric( $k ) && ( $v == 'FOR UPDATE' || $v == 'LOCK IN SHARE MODE' ) ) {
 559                                 $options[$k] = '';
 560                         }
 561                 }
 562
 563                 return parent::makeSelectOptions( $options );
 564         }
 565
 566         /**
 567          * @param array $options
 568          * @return string
 569          */
 570         protected function makeUpdateOptionsArray( $options ) {
 571                 $options = parent::makeUpdateOptionsArray( $options );
 572                 $options = self::fixIgnore( $options );
 573
 574                 return $options;
 575         }
 576
 577         /**
 578          * @param array $options
 579          * @return array
 580          */
 581         static function fixIgnore( $options ) {
 582                 # SQLite uses OR IGNORE not just IGNORE
 583                 foreach ( $options as $k => $v ) {
 584                         if ( $v == 'IGNORE' ) {
 585                                 $options[$k] = 'OR IGNORE';
 586                         }
 587                 }
 588
 589                 return $options;
 590         }
 591
 592         /**
 593          * @param array $options
 594          * @return string
 595          */
 596         function makeInsertOptions( $options ) {
 597                 $options = self::fixIgnore( $options );
 598
 599                 return parent::makeInsertOptions( $options );
 600         }
 601
 602         /**
 603          * Based on generic method (parent) with some prior SQLite-sepcific adjustments
 604          * @param string $table
 605          * @param array $a
 606          * @param string $fname
 607          * @param array $options
 608          * @return bool
 609          */
 610         function insert( $table, $a, $fname = __METHOD__, $options = [] ) {
 611                 if ( !count( $a ) ) {
 612                         return true;
 613                 }
 614
 615                 # SQLite can't handle multi-row inserts, so divide up into multiple single-row inserts
 616                 if ( isset( $a[0] ) && is_array( $a[0] ) ) {
 617                         $ret = true;
 618                         foreach ( $a as $v ) {
 619                                 if ( !parent::insert( $table, $v, "$fname/multi-row", $options ) ) {
 620                                         $ret = false;
 621                                 }
 622                         }
 623                 } else {
 624                         $ret = parent::insert( $table, $a, "$fname/single-row", $options );
 625                 }
 626
 627                 return $ret;
 628         }
 629
 630         /**
 631          * @param string $table
 632          * @param array $uniqueIndexes Unused
 633          * @param string|array $rows
 634          * @param string $fname
 635          * @return bool|ResultWrapper
 636          */
 637         function replace( $table, $uniqueIndexes, $rows, $fname = __METHOD__ ) {
 638                 if ( !count( $rows ) ) {
 639                         return true;
 640                 }
 641
 642                 # SQLite can't handle multi-row replaces, so divide up into multiple single-row queries
 643                 if ( isset( $rows[0] ) && is_array( $rows[0] ) ) {
 644                         $ret = true;
 645                         foreach ( $rows as $v ) {
 646                                 if ( !$this->nativeReplace( $table, $v, "$fname/multi-row" ) ) {
 647                                         $ret = false;
 648                                 }
 649                         }
 650                 } else {
 651                         $ret = $this->nativeReplace( $table, $rows, "$fname/single-row" );
 652                 }
 653
 654                 return $ret;
 655         }
 656
 657         /**
 658          * Returns the size of a text field, or -1 for "unlimited"
 659          * In SQLite this is SQLITE_MAX_LENGTH, by default 1GB. No way to query it though.
 660          *
 661          * @param string $table
 662          * @param string $field
 663          * @return int
 664          */
 665         function textFieldSize( $table, $field ) {
 666                 return -1;
 667         }
 668
 669         /**
 670          * @return bool
 671          */
 672         function unionSupportsOrderAndLimit() {
 673                 return false;
 674         }
 675
 676         /**
 677          * @param string $sqls
 678          * @param bool $all Whether to "UNION ALL" or not
 679          * @return string
 680          */
 681         function unionQueries( $sqls, $all ) {
 682                 $glue = $all ? ' UNION ALL ' : ' UNION ';
 683
 684                 return implode( $glue, $sqls );
 685         }
 686
 687         /**
 688          * @return bool
 689          */
 690         function wasDeadlock() {
 691                 return $this->lastErrno() == 5; // SQLITE_BUSY
 692         }
 693
 694         /**
 695          * @return bool
 696          */
 697         function wasErrorReissuable() {
 698                 return $this->lastErrno() == 17; // SQLITE_SCHEMA;
 699         }
 700
 701         /**
 702          * @return bool
 703          */
 704         function wasReadOnlyError() {
 705                 return $this->lastErrno() == 8; // SQLITE_READONLY;
 706         }
 707
 708         /**
 709          * @return string Wikitext of a link to the server software's web site
 710          */
 711         public function getSoftwareLink() {
 712                 return "[{{int:version-db-sqlite-url}} SQLite]";
 713         }
 714
 715         /**
 716          * @return string Version information from the database
 717          */
 718         function getServerVersion() {
 719                 $ver = $this->mConn->getAttribute( PDO::ATTR_SERVER_VERSION );
 720
 721                 return $ver;
 722         }
 723
 724         /**
 725          * @return string User-friendly database information
 726          */
 727         public function getServerInfo() {
 728                 return wfMessage( self::getFulltextSearchModule()
 729                         ? 'sqlite-has-fts'
 730                         : 'sqlite-no-fts', $this->getServerVersion() )->text();
 731         }
 732
 733         /**
 734          * Get information about a given field
 735          * Returns false if the field does not exist.
 736          *
 737          * @param string $table
 738          * @param string $field
 739          * @return SQLiteField|bool False on failure
 740          */
 741         function fieldInfo( $table, $field ) {
 742                 $tableName = $this->tableName( $table );
 743                 $sql = 'PRAGMA table_info(' . $this->addQuotes( $tableName ) . ')';
 744                 $res = $this->query( $sql, __METHOD__ );
 745                 foreach ( $res as $row ) {
 746                         if ( $row->name == $field ) {
 747                                 return new SQLiteField( $row, $tableName );
 748                         }
 749                 }
 750
 751                 return false;
 752         }
 753
 754         protected function doBegin( $fname = '' ) {
 755                 if ( $this->trxMode ) {
 756                         $this->query( "BEGIN {$this->trxMode}", $fname );
 757                 } else {
 758                         $this->query( 'BEGIN', $fname );
 759                 }
 760                 $this->mTrxLevel = 1;
 761         }
 762
 763         /**
 764          * @param string $s
 765          * @return string
 766          */
 767         function strencode( $s ) {
 768                 return substr( $this->addQuotes( $s ), 1, -1 );
 769         }
 770
 771         /**
 772          * @param string $b
 773          * @return Blob
 774          */
 775         function encodeBlob( $b ) {
 776                 return new Blob( $b );
 777         }
 778
 779         /**
 780          * @param Blob|string $b
 781          * @return string
 782          */
 783         function decodeBlob( $b ) {
 784                 if ( $b instanceof Blob ) {
 785                         $b = $b->fetch();
 786                 }
 787
 788                 return $b;
 789         }
 790
 791         /**
 792          * @param Blob|string $s
 793          * @return string
 794          */
 795         function addQuotes( $s ) {
 796                 if ( $s instanceof Blob ) {
 797                         return "x'" . bin2hex( $s->fetch() ) . "'";
 798                 } elseif ( is_bool( $s ) ) {
 799                         return (int)$s;
 800                 } elseif ( strpos( $s, "\0" ) !== false ) {
 801                         // SQLite doesn't support \0 in strings, so use the hex representation as a workaround.
 802                         // This is a known limitation of SQLite's mprintf function which PDO
 803                         // should work around, but doesn't. I have reported this to php.net as bug #63419:
 804                         // https://bugs.php.net/bug.php?id=63419
 805                         // There was already a similar report for SQLite3::escapeString, bug #62361:
 806                         // https://bugs.php.net/bug.php?id=62361
 807                         // There is an additional bug regarding sorting this data after insert
 808                         // on older versions of sqlite shipped with ubuntu 12.04
 809                         // https://phabricator.wikimedia.org/T74367
 810                         wfDebugLog(
 811                                 __CLASS__,
 812                                 __FUNCTION__ .
 813                                         ': Quoting value containing null byte. ' .
 814                                         'For consistency all binary data should have been ' .
 815                                         'first processed with self::encodeBlob()'
 816                         );
 817                         return "x'" . bin2hex( $s ) . "'";
 818                 } else {
 819                         return $this->mConn->quote( $s );
 820                 }
 821         }
 822
 823         /**
 824          * @return string
 825          */
 826         function buildLike() {
 827                 $params = func_get_args();
 828                 if ( count( $params ) > 0 && is_array( $params[0] ) ) {
 829                         $params = $params[0];
 830                 }
 831
 832                 return parent::buildLike( $params ) . "ESCAPE '\' ";
 833         }
 834
 835         /**
 836          * @return string
 837          */
 838         public function getSearchEngine() {
 839                 return "SearchSqlite";
 840         }
 841
 842         /**
 843          * No-op version of deadlockLoop
 844          *
 845          * @return mixed
 846          */
 847         public function deadlockLoop( /*...*/ ) {
 848                 $args = func_get_args();
 849                 $function = array_shift( $args );
 850
 851                 return call_user_func_array( $function, $args );
 852         }
 853
 854         /**
 855          * @param string $s
 856          * @return string
 857          */
 858         protected function replaceVars( $s ) {
 859                 $s = parent::replaceVars( $s );
 860                 if ( preg_match( '/^\s*(CREATE|ALTER) TABLE/i', $s ) ) {
 861                         // CREATE TABLE hacks to allow schema file sharing with MySQL
 862
 863                         // binary/varbinary column type -> blob
 864                         $s = preg_replace( '/\b(var)?binary(\(\d+\))/i', 'BLOB', $s );
 865                         // no such thing as unsigned
 866                         $s = preg_replace( '/\b(un)?signed\b/i', '', $s );
 867                         // INT -> INTEGER
 868                         $s = preg_replace( '/\b(tiny|small|medium|big|)int(\s*\(\s*\d+\s*\)|\b)/i', 'INTEGER', $s );
 869                         // floating point types -> REAL
 870                         $s = preg_replace(
 871                                 '/\b(float|double(\s+precision)?)(\s*\(\s*\d+\s*(,\s*\d+\s*)?\)|\b)/i',
 872                                 'REAL',
 873                                 $s
 874                         );
 875                         // varchar -> TEXT
 876                         $s = preg_replace( '/\b(var)?char\s*\(.*?\)/i', 'TEXT', $s );
 877                         // TEXT normalization
 878                         $s = preg_replace( '/\b(tiny|medium|long)text\b/i', 'TEXT', $s );
 879                         // BLOB normalization
 880                         $s = preg_replace( '/\b(tiny|small|medium|long|)blob\b/i', 'BLOB', $s );
 881                         // BOOL -> INTEGER
 882                         $s = preg_replace( '/\bbool(ean)?\b/i', 'INTEGER', $s );
 883                         // DATETIME -> TEXT
 884                         $s = preg_replace( '/\b(datetime|timestamp)\b/i', 'TEXT', $s );
 885                         // No ENUM type
 886                         $s = preg_replace( '/\benum\s*\([^)]*\)/i', 'TEXT', $s );
 887                         // binary collation type -> nothing
 888                         $s = preg_replace( '/\bbinary\b/i', '', $s );
 889                         // auto_increment -> autoincrement
 890                         $s = preg_replace( '/\bauto_increment\b/i', 'AUTOINCREMENT', $s );
 891                         // No explicit options
 892                         $s = preg_replace( '/\)[^);]*(;?)\s*$/', ')\1', $s );
 893                         // AUTOINCREMENT should immedidately follow PRIMARY KEY
 894                         $s = preg_replace( '/primary key (.*?) autoincrement/i', 'PRIMARY KEY AUTOINCREMENT $1', $s );
 895                 } elseif ( preg_match( '/^\s*CREATE (\s*(?:UNIQUE|FULLTEXT)\s+)?INDEX/i', $s ) ) {
 896                         // No truncated indexes
 897                         $s = preg_replace( '/\(\d+\)/', '', $s );
 898                         // No FULLTEXT
 899                         $s = preg_replace( '/\bfulltext\b/i', '', $s );
 900                 } elseif ( preg_match( '/^\s*DROP INDEX/i', $s ) ) {
 901                         // DROP INDEX is database-wide, not table-specific, so no ON <table> clause.
 902                         $s = preg_replace( '/\sON\s+[^\s]*/i', '', $s );
 903                 } elseif ( preg_match( '/^\s*INSERT IGNORE\b/i', $s ) ) {
 904                         // INSERT IGNORE --> INSERT OR IGNORE
 905                         $s = preg_replace( '/^\s*INSERT IGNORE\b/i', 'INSERT OR IGNORE', $s );
 906                 }
 907
 908                 return $s;
 909         }
 910
 911         public function lock( $lockName, $method, $timeout = 5 ) {
 912                 if ( !is_dir( "{$this->dbDir}/locks" ) ) { // create dir as needed
 913                         if ( !is_writable( $this->dbDir ) || !mkdir( "{$this->dbDir}/locks" ) ) {
 914                                 throw new DBError( $this, "Cannot create directory \"{$this->dbDir}/locks\"." );
 915                         }
 916                 }
 917
 918                 return $this->lockMgr->lock( [ $lockName ], LockManager::LOCK_EX, $timeout )->isOK();
 919         }
 920
 921         public function unlock( $lockName, $method ) {
 922                 return $this->lockMgr->unlock( [ $lockName ], LockManager::LOCK_EX )->isOK();
 923         }
 924
 925         /**
 926          * Build a concatenation list to feed into a SQL query
 927          *
 928          * @param string[] $stringList
 929          * @return string
 930          */
 931         function buildConcat( $stringList ) {
 932                 return '(' . implode( ') || (', $stringList ) . ')';
 933         }
 934
 935         public function buildGroupConcatField(
 936                 $delim, $table, $field, $conds = '', $join_conds = []
 937         ) {
 938                 $fld = "group_concat($field," . $this->addQuotes( $delim ) . ')';
 939
 940                 return '(' . $this->selectSQLText( $table, $fld, $conds, null, [], $join_conds ) . ')';
 941         }
 942
 943         /**
 944          * @throws MWException
 945          * @param string $oldName
 946          * @param string $newName
 947          * @param bool $temporary
 948          * @param string $fname
 949          * @return bool|ResultWrapper
 950          */
 951         function duplicateTableStructure( $oldName, $newName, $temporary = false, $fname = __METHOD__ ) {
 952                 $res = $this->query( "SELECT sql FROM sqlite_master WHERE tbl_name=" .
 953                         $this->addQuotes( $oldName ) . " AND type='table'", $fname );
 954                 $obj = $this->fetchObject( $res );
 955                 if ( !$obj ) {
 956                         throw new MWException( "Couldn't retrieve structure for table $oldName" );
 957                 }
 958                 $sql = $obj->sql;
 959                 $sql = preg_replace(
 960                         '/(?<=\W)"?' . preg_quote( trim( $this->addIdentifierQuotes( $oldName ), '"' ) ) . '"?(?=\W)/',
 961                         $this->addIdentifierQuotes( $newName ),
 962                         $sql,
 963                         1
 964                 );
 965                 if ( $temporary ) {
 966                         if ( preg_match( '/^\\s*CREATE\\s+VIRTUAL\\s+TABLE\b/i', $sql ) ) {
 967                                 wfDebug( "Table $oldName is virtual, can't create a temporary duplicate.\n" );
 968                         } else {
 969                                 $sql = str_replace( 'CREATE TABLE', 'CREATE TEMPORARY TABLE', $sql );
 970                         }
 971                 }
 972
 973                 $res = $this->query( $sql, $fname );
 974
 975                 // Take over indexes
 976                 $indexList = $this->query( 'PRAGMA INDEX_LIST(' . $this->addQuotes( $oldName ) . ')' );
 977                 foreach ( $indexList as $index ) {
 978                         if ( strpos( $index->name, 'sqlite_autoindex' ) === 0 ) {
 979                                 continue;
 980                         }
 981
 982                         if ( $index->unique ) {
 983                                 $sql = 'CREATE UNIQUE INDEX';
 984                         } else {
 985                                 $sql = 'CREATE INDEX';
 986                         }
 987                         // Try to come up with a new index name, given indexes have database scope in SQLite
 988                         $indexName = $newName . '_' . $index->name;
 989                         $sql .= ' ' . $indexName . ' ON ' . $newName;
 990
 991                         $indexInfo = $this->query( 'PRAGMA INDEX_INFO(' . $this->addQuotes( $index->name ) . ')' );
 992                         $fields = [];
 993                         foreach ( $indexInfo as $indexInfoRow ) {
 994                                 $fields[$indexInfoRow->seqno] = $indexInfoRow->name;
 995                         }
 996
 997                         $sql .= '(' . implode( ',', $fields ) . ')';
 998
 999                         $this->query( $sql );
1000                 }
1001
1002                 return $res;
1003         }
1004
1005         /**
1006          * List all tables on the database
1007          *
1008          * @param string $prefix Only show tables with this prefix, e.g. mw_
1009          * @param string $fname Calling function name
1010          *
1011          * @return array
1012          */
1013         function listTables( $prefix = null, $fname = __METHOD__ ) {
1014                 $result = $this->select(
1015                         'sqlite_master',
1016                         'name',
1017                         "type='table'"
1018                 );
1019
1020                 $endArray = [];
1021
1022                 foreach ( $result as $table ) {
1023                         $vars = get_object_vars( $table );
1024                         $table = array_pop( $vars );
1025
1026                         if ( !$prefix || strpos( $table, $prefix ) === 0 ) {
1027                                 if ( strpos( $table, 'sqlite_' ) !== 0 ) {
1028                                         $endArray[] = $table;
1029                                 }
1030                         }
1031                 }
1032
1033                 return $endArray;
1034         }
1035
1036         /**
1037          * @return string
1038          */
1039         public function __toString() {
1040                 return 'SQLite ' . (string)$this->mConn->getAttribute( PDO::ATTR_SERVER_VERSION );
1041         }
1042
1043 } // end DatabaseSqlite class
1044
1045 /**
1046  * @ingroup Database
1047  */
1048 class SQLiteField implements Field {
1049         private $info, $tableName;
1050
1051         function __construct( $info, $tableName ) {
1052                 $this->info = $info;
1053                 $this->tableName = $tableName;
1054         }
1055
1056         function name() {
1057                 return $this->info->name;
1058         }
1059
1060         function tableName() {
1061                 return $this->tableName;
1062         }
1063
1064         function defaultValue() {
1065                 if ( is_string( $this->info->dflt_value ) ) {
1066                         // Typically quoted
1067                         if ( preg_match( '/^\'(.*)\'$', $this->info->dflt_value ) ) {
1068                                 return str_replace( "''", "'", $this->info->dflt_value );
1069                         }
1070                 }
1071
1072                 return $this->info->dflt_value;
1073         }
1074
1075         /**
1076          * @return bool
1077          */
1078         function isNullable() {
1079                 return !$this->info->notnull;
1080         }
1081
1082         function type() {
1083                 return $this->info->type;
1084         }
1085 } // end SQLiteField