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 DatabaseBase {
  29         /** @var bool Whether full text is enabled */
  30         private static $fulltextEnabled = null;
  31
  32         /** @var string File name for SQLite database file */
  33         public $mDatabaseFile;
  34
  35         /** @var int The number of rows affected as an integer */
  36         protected $mAffectedRows;
  37
  38         /** @var resource */
  39         protected $mLastResult;
  40
  41         /** @var PDO */
  42         protected $mConn;
  43
  44         function __construct( $p = null ) {
  45                 global $wgSharedDB;
  46
  47                 if ( !is_array( $p ) ) { // legacy calling pattern
  48                         wfDeprecated( __METHOD__ . " method called without parameter array.", "1.22" );
  49                         $args = func_get_args();
  50                         $p = array(
  51                                 'host' => isset( $args[0] ) ? $args[0] : false,
  52                                 'user' => isset( $args[1] ) ? $args[1] : false,
  53                                 'password' => isset( $args[2] ) ? $args[2] : false,
  54                                 'dbname' => isset( $args[3] ) ? $args[3] : false,
  55                                 'flags' => isset( $args[4] ) ? $args[4] : 0,
  56                                 'tablePrefix' => isset( $args[5] ) ? $args[5] : 'get from global',
  57                                 'foreign' => isset( $args[6] ) ? $args[6] : false
  58                         );
  59                 }
  60                 $this->mDBname = $p['dbname'];
  61                 parent::__construct( $p );
  62                 // parent doesn't open when $user is false, but we can work with $dbName
  63                 if ( $p['dbname'] && !$this->isOpen() ) {
  64                         if ( $this->open( $p['host'], $p['user'], $p['password'], $p['dbname'] ) ) {
  65                                 if ( $wgSharedDB ) {
  66                                         $this->attachDatabase( $wgSharedDB );
  67                                 }
  68                         }
  69                 }
  70         }
  71
  72         /**
  73          * @return string
  74          */
  75         function getType() {
  76                 return 'sqlite';
  77         }
  78
  79         /**
  80          * @todo Check if it should be true like parent class
  81          *
  82          * @return bool
  83          */
  84         function implicitGroupby() {
  85                 return false;
  86         }
  87
  88         /** Open an SQLite database and return a resource handle to it
  89          *  NOTE: only $dbName is used, the other parameters are irrelevant for SQLite databases
  90          *
  91          * @param string $server
  92          * @param string $user
  93          * @param string $pass
  94          * @param string $dbName
  95          *
  96          * @throws DBConnectionError
  97          * @return PDO
  98          */
  99         function open( $server, $user, $pass, $dbName ) {
 100                 global $wgSQLiteDataDir;
 101
 102                 $this->close();
 103                 $fileName = self::generateFileName( $wgSQLiteDataDir, $dbName );
 104                 if ( !is_readable( $fileName ) ) {
 105                         $this->mConn = false;
 106                         throw new DBConnectionError( $this, "SQLite database not accessible" );
 107                 }
 108                 $this->openFile( $fileName );
 109
 110                 return $this->mConn;
 111         }
 112
 113         /**
 114          * Opens a database file
 115          *
 116          * @param string $fileName
 117          * @throws DBConnectionError
 118          * @return PDO|bool SQL connection or false if failed
 119          */
 120         function openFile( $fileName ) {
 121                 $err = false;
 122
 123                 $this->mDatabaseFile = $fileName;
 124                 try {
 125                         if ( $this->mFlags & DBO_PERSISTENT ) {
 126                                 $this->mConn = new PDO( "sqlite:$fileName", '', '',
 127                                         array( PDO::ATTR_PERSISTENT => true ) );
 128                         } else {
 129                                 $this->mConn = new PDO( "sqlite:$fileName", '', '' );
 130                         }
 131                 } catch ( PDOException $e ) {
 132                         $err = $e->getMessage();
 133                 }
 134
 135                 if ( !$this->mConn ) {
 136                         wfDebug( "DB connection error: $err\n" );
 137                         throw new DBConnectionError( $this, $err );
 138                 }
 139
 140                 $this->mOpened = !!$this->mConn;
 141                 # set error codes only, don't raise exceptions
 142                 if ( $this->mOpened ) {
 143                         $this->mConn->setAttribute( PDO::ATTR_ERRMODE, PDO::ERRMODE_SILENT );
 144                         # Enforce LIKE to be case sensitive, just like MySQL
 145                         $this->query( 'PRAGMA case_sensitive_like = 1' );
 146
 147                         return $this->mConn;
 148                 }
 149
 150                 return false;
 151         }
 152
 153         /**
 154          * Does not actually close the connection, just destroys the reference for GC to do its work
 155          * @return bool
 156          */
 157         protected function closeConnection() {
 158                 $this->mConn = null;
 159
 160                 return true;
 161         }
 162
 163         /**
 164          * Generates a database file name. Explicitly public for installer.
 165          * @param string $dir Directory where database resides
 166          * @param string $dbName Database name
 167          * @return string
 168          */
 169         public static function generateFileName( $dir, $dbName ) {
 170                 return "$dir/$dbName.sqlite";
 171         }
 172
 173         /**
 174          * Check if the searchindext table is FTS enabled.
 175          * @return bool False if not enabled.
 176          */
 177         function checkForEnabledSearch() {
 178                 if ( self::$fulltextEnabled === null ) {
 179                         self::$fulltextEnabled = false;
 180                         $table = $this->tableName( 'searchindex' );
 181                         $res = $this->query( "SELECT sql FROM sqlite_master WHERE tbl_name = '$table'", __METHOD__ );
 182                         if ( $res ) {
 183                                 $row = $res->fetchRow();
 184                                 self::$fulltextEnabled = stristr( $row['sql'], 'fts' ) !== false;
 185                         }
 186                 }
 187
 188                 return self::$fulltextEnabled;
 189         }
 190
 191         /**
 192          * Returns version of currently supported SQLite fulltext search module or false if none present.
 193          * @return string
 194          */
 195         static function getFulltextSearchModule() {
 196                 static $cachedResult = null;
 197                 if ( $cachedResult !== null ) {
 198                         return $cachedResult;
 199                 }
 200                 $cachedResult = false;
 201                 $table = 'dummy_search_test';
 202
 203                 $db = new DatabaseSqliteStandalone( ':memory:' );
 204
 205                 if ( $db->query( "CREATE VIRTUAL TABLE $table USING FTS3(dummy_field)", __METHOD__, true ) ) {
 206                         $cachedResult = 'FTS3';
 207                 }
 208                 $db->close();
 209
 210                 return $cachedResult;
 211         }
 212
 213         /**
 214          * Attaches external database to our connection, see http://sqlite.org/lang_attach.html
 215          * for details.
 216          *
 217          * @param string $name Database name to be used in queries like
 218          *   SELECT foo FROM dbname.table
 219          * @param bool|string $file Database file name. If omitted, will be generated
 220          *   using $name and $wgSQLiteDataDir
 221          * @param string $fname Calling function name
 222          * @return ResultWrapper
 223          */
 224         function attachDatabase( $name, $file = false, $fname = __METHOD__ ) {
 225                 global $wgSQLiteDataDir;
 226                 if ( !$file ) {
 227                         $file = self::generateFileName( $wgSQLiteDataDir, $name );
 228                 }
 229                 $file = $this->addQuotes( $file );
 230
 231                 return $this->query( "ATTACH DATABASE $file AS $name", $fname );
 232         }
 233
 234         /**
 235          * @see DatabaseBase::isWriteQuery()
 236          *
 237          * @param $sql string
 238          * @return bool
 239          */
 240         function isWriteQuery( $sql ) {
 241                 return parent::isWriteQuery( $sql ) && !preg_match( '/^ATTACH\b/i', $sql );
 242         }
 243
 244         /**
 245          * SQLite doesn't allow buffered results or data seeking etc, so we'll use fetchAll as the result
 246          *
 247          * @param string $sql
 248          * @return bool|ResultWrapper
 249          */
 250         protected function doQuery( $sql ) {
 251                 $res = $this->mConn->query( $sql );
 252                 if ( $res === false ) {
 253                         return false;
 254                 } else {
 255                         $r = $res instanceof ResultWrapper ? $res->result : $res;
 256                         $this->mAffectedRows = $r->rowCount();
 257                         $res = new ResultWrapper( $this, $r->fetchAll() );
 258                 }
 259
 260                 return $res;
 261         }
 262
 263         /**
 264          * @param ResultWrapper|mixed $res
 265          */
 266         function freeResult( $res ) {
 267                 if ( $res instanceof ResultWrapper ) {
 268                         $res->result = null;
 269                 } else {
 270                         $res = null;
 271                 }
 272         }
 273
 274         /**
 275          * @param ResultWrapper|array $res
 276          * @return stdClass|bool
 277          */
 278         function fetchObject( $res ) {
 279                 if ( $res instanceof ResultWrapper ) {
 280                         $r =& $res->result;
 281                 } else {
 282                         $r =& $res;
 283                 }
 284
 285                 $cur = current( $r );
 286                 if ( is_array( $cur ) ) {
 287                         next( $r );
 288                         $obj = new stdClass;
 289                         foreach ( $cur as $k => $v ) {
 290                                 if ( !is_numeric( $k ) ) {
 291                                         $obj->$k = $v;
 292                                 }
 293                         }
 294
 295                         return $obj;
 296                 }
 297
 298                 return false;
 299         }
 300
 301         /**
 302          * @param ResultWrapper|mixed $res
 303          * @return array|bool
 304          */
 305         function fetchRow( $res ) {
 306                 if ( $res instanceof ResultWrapper ) {
 307                         $r =& $res->result;
 308                 } else {
 309                         $r =& $res;
 310                 }
 311                 $cur = current( $r );
 312                 if ( is_array( $cur ) ) {
 313                         next( $r );
 314
 315                         return $cur;
 316                 }
 317
 318                 return false;
 319         }
 320
 321         /**
 322          * The PDO::Statement class implements the array interface so count() will work
 323          *
 324          * @param ResultWrapper|array $res
 325          * @return int
 326          */
 327         function numRows( $res ) {
 328                 $r = $res instanceof ResultWrapper ? $res->result : $res;
 329
 330                 return count( $r );
 331         }
 332
 333         /**
 334          * @param ResultWrapper $res
 335          * @return int
 336          */
 337         function numFields( $res ) {
 338                 $r = $res instanceof ResultWrapper ? $res->result : $res;
 339
 340                 return is_array( $r ) ? count( $r[0] ) : 0;
 341         }
 342
 343         /**
 344          * @param ResultWrapper $res
 345          * @param $n
 346          * @return bool
 347          */
 348         function fieldName( $res, $n ) {
 349                 $r = $res instanceof ResultWrapper ? $res->result : $res;
 350                 if ( is_array( $r ) ) {
 351                         $keys = array_keys( $r[0] );
 352
 353                         return $keys[$n];
 354                 }
 355
 356                 return false;
 357         }
 358
 359         /**
 360          * Use MySQL's naming (accounts for prefix etc) but remove surrounding backticks
 361          *
 362          * @param string $name
 363          * @param string $format
 364          * @return string
 365          */
 366         function tableName( $name, $format = 'quoted' ) {
 367                 // table names starting with sqlite_ are reserved
 368                 if ( strpos( $name, 'sqlite_' ) === 0 ) {
 369                         return $name;
 370                 }
 371
 372                 return str_replace( '"', '', parent::tableName( $name, $format ) );
 373         }
 374
 375         /**
 376          * Index names have DB scope
 377          *
 378          * @param string $index
 379          * @return string
 380          */
 381         function indexName( $index ) {
 382                 return $index;
 383         }
 384
 385         /**
 386          * This must be called after nextSequenceVal
 387          *
 388          * @return int
 389          */
 390         function insertId() {
 391                 // PDO::lastInsertId yields a string :(
 392                 return intval( $this->mConn->lastInsertId() );
 393         }
 394
 395         /**
 396          * @param ResultWrapper|array $res
 397          * @param int $row
 398          */
 399         function dataSeek( $res, $row ) {
 400                 if ( $res instanceof ResultWrapper ) {
 401                         $r =& $res->result;
 402                 } else {
 403                         $r =& $res;
 404                 }
 405                 reset( $r );
 406                 if ( $row > 0 ) {
 407                         for ( $i = 0; $i < $row; $i++ ) {
 408                                 next( $r );
 409                         }
 410                 }
 411         }
 412
 413         /**
 414          * @return string
 415          */
 416         function lastError() {
 417                 if ( !is_object( $this->mConn ) ) {
 418                         return "Cannot return last error, no db connection";
 419                 }
 420                 $e = $this->mConn->errorInfo();
 421
 422                 return isset( $e[2] ) ? $e[2] : '';
 423         }
 424
 425         /**
 426          * @return string
 427          */
 428         function lastErrno() {
 429                 if ( !is_object( $this->mConn ) ) {
 430                         return "Cannot return last error, no db connection";
 431                 } else {
 432                         $info = $this->mConn->errorInfo();
 433
 434                         return $info[1];
 435                 }
 436         }
 437
 438         /**
 439          * @return int
 440          */
 441         function affectedRows() {
 442                 return $this->mAffectedRows;
 443         }
 444
 445         /**
 446          * Returns information about an index
 447          * Returns false if the index does not exist
 448          * - if errors are explicitly ignored, returns NULL on failure
 449          *
 450          * @param string $table
 451          * @param string $index
 452          * @param string $fname
 453          * @return array
 454          */
 455         function indexInfo( $table, $index, $fname = __METHOD__ ) {
 456                 $sql = 'PRAGMA index_info(' . $this->addQuotes( $this->indexName( $index ) ) . ')';
 457                 $res = $this->query( $sql, $fname );
 458                 if ( !$res ) {
 459                         return null;
 460                 }
 461                 if ( $res->numRows() == 0 ) {
 462                         return false;
 463                 }
 464                 $info = array();
 465                 foreach ( $res as $row ) {
 466                         $info[] = $row->name;
 467                 }
 468
 469                 return $info;
 470         }
 471
 472         /**
 473          * @param string $table
 474          * @param string $index
 475          * @param string $fname
 476          * @return bool|null
 477          */
 478         function indexUnique( $table, $index, $fname = __METHOD__ ) {
 479                 $row = $this->selectRow( 'sqlite_master', '*',
 480                         array(
 481                                 'type' => 'index',
 482                                 'name' => $this->indexName( $index ),
 483                         ), $fname );
 484                 if ( !$row || !isset( $row->sql ) ) {
 485                         return null;
 486                 }
 487
 488                 // $row->sql will be of the form CREATE [UNIQUE] INDEX ...
 489                 $indexPos = strpos( $row->sql, 'INDEX' );
 490                 if ( $indexPos === false ) {
 491                         return null;
 492                 }
 493                 $firstPart = substr( $row->sql, 0, $indexPos );
 494                 $options = explode( ' ', $firstPart );
 495
 496                 return in_array( 'UNIQUE', $options );
 497         }
 498
 499         /**
 500          * Filter the options used in SELECT statements
 501          *
 502          * @param array $options
 503          * @return array
 504          */
 505         function makeSelectOptions( $options ) {
 506                 foreach ( $options as $k => $v ) {
 507                         if ( is_numeric( $k ) && ( $v == 'FOR UPDATE' || $v == 'LOCK IN SHARE MODE' ) ) {
 508                                 $options[$k] = '';
 509                         }
 510                 }
 511
 512                 return parent::makeSelectOptions( $options );
 513         }
 514
 515         /**
 516          * @param array $options
 517          * @return string
 518          */
 519         protected function makeUpdateOptions( $options ) {
 520                 $options = self::fixIgnore( $options );
 521
 522                 return parent::makeUpdateOptions( $options );
 523         }
 524
 525         /**
 526          * @param array $options
 527          * @return array
 528          */
 529         static function fixIgnore( $options ) {
 530                 # SQLite uses OR IGNORE not just IGNORE
 531                 foreach ( $options as $k => $v ) {
 532                         if ( $v == 'IGNORE' ) {
 533                                 $options[$k] = 'OR IGNORE';
 534                         }
 535                 }
 536
 537                 return $options;
 538         }
 539
 540         /**
 541          * @param array $options
 542          * @return string
 543          */
 544         function makeInsertOptions( $options ) {
 545                 $options = self::fixIgnore( $options );
 546
 547                 return parent::makeInsertOptions( $options );
 548         }
 549
 550         /**
 551          * Based on generic method (parent) with some prior SQLite-sepcific adjustments
 552          * @param string $table
 553          * @param array $a
 554          * @param string $fname
 555          * @param array $options
 556          * @return bool
 557          */
 558         function insert( $table, $a, $fname = __METHOD__, $options = array() ) {
 559                 if ( !count( $a ) ) {
 560                         return true;
 561                 }
 562
 563                 # SQLite can't handle multi-row inserts, so divide up into multiple single-row inserts
 564                 if ( isset( $a[0] ) && is_array( $a[0] ) ) {
 565                         $ret = true;
 566                         foreach ( $a as $v ) {
 567                                 if ( !parent::insert( $table, $v, "$fname/multi-row", $options ) ) {
 568                                         $ret = false;
 569                                 }
 570                         }
 571                 } else {
 572                         $ret = parent::insert( $table, $a, "$fname/single-row", $options );
 573                 }
 574
 575                 return $ret;
 576         }
 577
 578         /**
 579          * @param string $table
 580          * @param array $uniqueIndexes Unused
 581          * @param string|array $rows
 582          * @param string $fname
 583          * @return bool|ResultWrapper
 584          */
 585         function replace( $table, $uniqueIndexes, $rows, $fname = __METHOD__ ) {
 586                 if ( !count( $rows ) ) {
 587                         return true;
 588                 }
 589
 590                 # SQLite can't handle multi-row replaces, so divide up into multiple single-row queries
 591                 if ( isset( $rows[0] ) && is_array( $rows[0] ) ) {
 592                         $ret = true;
 593                         foreach ( $rows as $v ) {
 594                                 if ( !$this->nativeReplace( $table, $v, "$fname/multi-row" ) ) {
 595                                         $ret = false;
 596                                 }
 597                         }
 598                 } else {
 599                         $ret = $this->nativeReplace( $table, $rows, "$fname/single-row" );
 600                 }
 601
 602                 return $ret;
 603         }
 604
 605         /**
 606          * Returns the size of a text field, or -1 for "unlimited"
 607          * In SQLite this is SQLITE_MAX_LENGTH, by default 1GB. No way to query it though.
 608          *
 609          * @param string $table
 610          * @param string $field
 611          * @return int
 612          */
 613         function textFieldSize( $table, $field ) {
 614                 return -1;
 615         }
 616
 617         /**
 618          * @return bool
 619          */
 620         function unionSupportsOrderAndLimit() {
 621                 return false;
 622         }
 623
 624         /**
 625          * @param string $sqls
 626          * @param bool $all Whether to "UNION ALL" or not
 627          * @return string
 628          */
 629         function unionQueries( $sqls, $all ) {
 630                 $glue = $all ? ' UNION ALL ' : ' UNION ';
 631
 632                 return implode( $glue, $sqls );
 633         }
 634
 635         /**
 636          * @return bool
 637          */
 638         function wasDeadlock() {
 639                 return $this->lastErrno() == 5; // SQLITE_BUSY
 640         }
 641
 642         /**
 643          * @return bool
 644          */
 645         function wasErrorReissuable() {
 646                 return $this->lastErrno() == 17; // SQLITE_SCHEMA;
 647         }
 648
 649         /**
 650          * @return bool
 651          */
 652         function wasReadOnlyError() {
 653                 return $this->lastErrno() == 8; // SQLITE_READONLY;
 654         }
 655
 656         /**
 657          * @return string wikitext of a link to the server software's web site
 658          */
 659         public function getSoftwareLink() {
 660                 return "[{{int:version-db-sqlite-url}} SQLite]";
 661         }
 662
 663         /**
 664          * @return string Version information from the database
 665          */
 666         function getServerVersion() {
 667                 $ver = $this->mConn->getAttribute( PDO::ATTR_SERVER_VERSION );
 668
 669                 return $ver;
 670         }
 671
 672         /**
 673          * @return string User-friendly database information
 674          */
 675         public function getServerInfo() {
 676                 return wfMessage( self::getFulltextSearchModule()
 677                         ? 'sqlite-has-fts'
 678                         : 'sqlite-no-fts', $this->getServerVersion() )->text();
 679         }
 680
 681         /**
 682          * Get information about a given field
 683          * Returns false if the field does not exist.
 684          *
 685          * @param string $table
 686          * @param string $field
 687          * @return SQLiteField|bool False on failure
 688          */
 689         function fieldInfo( $table, $field ) {
 690                 $tableName = $this->tableName( $table );
 691                 $sql = 'PRAGMA table_info(' . $this->addQuotes( $tableName ) . ')';
 692                 $res = $this->query( $sql, __METHOD__ );
 693                 foreach ( $res as $row ) {
 694                         if ( $row->name == $field ) {
 695                                 return new SQLiteField( $row, $tableName );
 696                         }
 697                 }
 698
 699                 return false;
 700         }
 701
 702         protected function doBegin( $fname = '' ) {
 703                 if ( $this->mTrxLevel == 1 ) {
 704                         $this->commit( __METHOD__ );
 705                 }
 706                 try {
 707                         $this->mConn->beginTransaction();
 708                 } catch ( PDOException $e ) {
 709                         throw new DBUnexpectedError( $this, 'Error in BEGIN query: ' . $e->getMessage() );
 710                 }
 711                 $this->mTrxLevel = 1;
 712         }
 713
 714         protected function doCommit( $fname = '' ) {
 715                 if ( $this->mTrxLevel == 0 ) {
 716                         return;
 717                 }
 718                 try {
 719                         $this->mConn->commit();
 720                 } catch ( PDOException $e ) {
 721                         throw new DBUnexpectedError( $this, 'Error in COMMIT query: ' . $e->getMessage() );
 722                 }
 723                 $this->mTrxLevel = 0;
 724         }
 725
 726         protected function doRollback( $fname = '' ) {
 727                 if ( $this->mTrxLevel == 0 ) {
 728                         return;
 729                 }
 730                 $this->mConn->rollBack();
 731                 $this->mTrxLevel = 0;
 732         }
 733
 734         /**
 735          * @param string $s
 736          * @return string
 737          */
 738         function strencode( $s ) {
 739                 return substr( $this->addQuotes( $s ), 1, -1 );
 740         }
 741
 742         /**
 743          * @param $b
 744          * @return Blob
 745          */
 746         function encodeBlob( $b ) {
 747                 return new Blob( $b );
 748         }
 749
 750         /**
 751          * @param $b Blob|string
 752          * @return string
 753          */
 754         function decodeBlob( $b ) {
 755                 if ( $b instanceof Blob ) {
 756                         $b = $b->fetch();
 757                 }
 758
 759                 return $b;
 760         }
 761
 762         /**
 763          * @param Blob|string $s
 764          * @return string
 765          */
 766         function addQuotes( $s ) {
 767                 if ( $s instanceof Blob ) {
 768                         return "x'" . bin2hex( $s->fetch() ) . "'";
 769                 } elseif ( is_bool( $s ) ) {
 770                         return (int)$s;
 771                 } elseif ( strpos( $s, "\0" ) !== false ) {
 772                         // SQLite doesn't support \0 in strings, so use the hex representation as a workaround.
 773                         // This is a known limitation of SQLite's mprintf function which PDO should work around,
 774                         // but doesn't. I have reported this to php.net as bug #63419:
 775                         // https://bugs.php.net/bug.php?id=63419
 776                         // There was already a similar report for SQLite3::escapeString, bug #62361:
 777                         // https://bugs.php.net/bug.php?id=62361
 778                         return "x'" . bin2hex( $s ) . "'";
 779                 } else {
 780                         return $this->mConn->quote( $s );
 781                 }
 782         }
 783
 784         /**
 785          * @return string
 786          */
 787         function buildLike() {
 788                 $params = func_get_args();
 789                 if ( count( $params ) > 0 && is_array( $params[0] ) ) {
 790                         $params = $params[0];
 791                 }
 792
 793                 return parent::buildLike( $params ) . "ESCAPE '\' ";
 794         }
 795
 796         /**
 797          * @return string
 798          */
 799         public function getSearchEngine() {
 800                 return "SearchSqlite";
 801         }
 802
 803         /**
 804          * No-op version of deadlockLoop
 805          *
 806          * @return mixed
 807          */
 808         public function deadlockLoop( /*...*/ ) {
 809                 $args = func_get_args();
 810                 $function = array_shift( $args );
 811
 812                 return call_user_func_array( $function, $args );
 813         }
 814
 815         /**
 816          * @param string $s
 817          * @return string
 818          */
 819         protected function replaceVars( $s ) {
 820                 $s = parent::replaceVars( $s );
 821                 if ( preg_match( '/^\s*(CREATE|ALTER) TABLE/i', $s ) ) {
 822                         // CREATE TABLE hacks to allow schema file sharing with MySQL
 823
 824                         // binary/varbinary column type -> blob
 825                         $s = preg_replace( '/\b(var)?binary(\(\d+\))/i', 'BLOB', $s );
 826                         // no such thing as unsigned
 827                         $s = preg_replace( '/\b(un)?signed\b/i', '', $s );
 828                         // INT -> INTEGER
 829                         $s = preg_replace( '/\b(tiny|small|medium|big|)int(\s*\(\s*\d+\s*\)|\b)/i', 'INTEGER', $s );
 830                         // floating point types -> REAL
 831                         $s = preg_replace(
 832                                 '/\b(float|double(\s+precision)?)(\s*\(\s*\d+\s*(,\s*\d+\s*)?\)|\b)/i',
 833                                 'REAL',
 834                                 $s
 835                         );
 836                         // varchar -> TEXT
 837                         $s = preg_replace( '/\b(var)?char\s*\(.*?\)/i', 'TEXT', $s );
 838                         // TEXT normalization
 839                         $s = preg_replace( '/\b(tiny|medium|long)text\b/i', 'TEXT', $s );
 840                         // BLOB normalization
 841                         $s = preg_replace( '/\b(tiny|small|medium|long|)blob\b/i', 'BLOB', $s );
 842                         // BOOL -> INTEGER
 843                         $s = preg_replace( '/\bbool(ean)?\b/i', 'INTEGER', $s );
 844                         // DATETIME -> TEXT
 845                         $s = preg_replace( '/\b(datetime|timestamp)\b/i', 'TEXT', $s );
 846                         // No ENUM type
 847                         $s = preg_replace( '/\benum\s*\([^)]*\)/i', 'TEXT', $s );
 848                         // binary collation type -> nothing
 849                         $s = preg_replace( '/\bbinary\b/i', '', $s );
 850                         // auto_increment -> autoincrement
 851                         $s = preg_replace( '/\bauto_increment\b/i', 'AUTOINCREMENT', $s );
 852                         // No explicit options
 853                         $s = preg_replace( '/\)[^);]*(;?)\s*$/', ')\1', $s );
 854                         // AUTOINCREMENT should immedidately follow PRIMARY KEY
 855                         $s = preg_replace( '/primary key (.*?) autoincrement/i', 'PRIMARY KEY AUTOINCREMENT $1', $s );
 856                 } elseif ( preg_match( '/^\s*CREATE (\s*(?:UNIQUE|FULLTEXT)\s+)?INDEX/i', $s ) ) {
 857                         // No truncated indexes
 858                         $s = preg_replace( '/\(\d+\)/', '', $s );
 859                         // No FULLTEXT
 860                         $s = preg_replace( '/\bfulltext\b/i', '', $s );
 861                 } elseif ( preg_match( '/^\s*DROP INDEX/i', $s ) ) {
 862                         // DROP INDEX is database-wide, not table-specific, so no ON <table> clause.
 863                         $s = preg_replace( '/\sON\s+[^\s]*/i', '', $s );
 864                 }
 865
 866                 return $s;
 867         }
 868
 869         /**
 870          * Build a concatenation list to feed into a SQL query
 871          *
 872          * @param string[] $stringList
 873          * @return string
 874          */
 875         function buildConcat( $stringList ) {
 876                 return '(' . implode( ') || (', $stringList ) . ')';
 877         }
 878
 879         public function buildGroupConcatField(
 880                 $delim, $table, $field, $conds = '', $join_conds = array()
 881         ) {
 882                 $fld = "group_concat($field," . $this->addQuotes( $delim ) . ')';
 883
 884                 return '(' . $this->selectSQLText( $table, $fld, $conds, null, array(), $join_conds ) . ')';
 885         }
 886
 887         /**
 888          * @throws MWException
 889          * @param string $oldName
 890          * @param string $newName
 891          * @param bool $temporary
 892          * @param string $fname
 893          * @return bool|ResultWrapper
 894          */
 895         function duplicateTableStructure( $oldName, $newName, $temporary = false, $fname = __METHOD__ ) {
 896                 $res = $this->query( "SELECT sql FROM sqlite_master WHERE tbl_name=" .
 897                         $this->addQuotes( $oldName ) . " AND type='table'", $fname );
 898                 $obj = $this->fetchObject( $res );
 899                 if ( !$obj ) {
 900                         throw new MWException( "Couldn't retrieve structure for table $oldName" );
 901                 }
 902                 $sql = $obj->sql;
 903                 $sql = preg_replace(
 904                         '/(?<=\W)"?' . preg_quote( trim( $this->addIdentifierQuotes( $oldName ), '"' ) ) . '"?(?=\W)/',
 905                         $this->addIdentifierQuotes( $newName ),
 906                         $sql,
 907                         1
 908                 );
 909                 if ( $temporary ) {
 910                         if ( preg_match( '/^\\s*CREATE\\s+VIRTUAL\\s+TABLE\b/i', $sql ) ) {
 911                                 wfDebug( "Table $oldName is virtual, can't create a temporary duplicate.\n" );
 912                         } else {
 913                                 $sql = str_replace( 'CREATE TABLE', 'CREATE TEMPORARY TABLE', $sql );
 914                         }
 915                 }
 916
 917                 return $this->query( $sql, $fname );
 918         }
 919
 920         /**
 921          * List all tables on the database
 922          *
 923          * @param string $prefix Only show tables with this prefix, e.g. mw_
 924          * @param string $fname Calling function name
 925          *
 926          * @return array
 927          */
 928         function listTables( $prefix = null, $fname = __METHOD__ ) {
 929                 $result = $this->select(
 930                         'sqlite_master',
 931                         'name',
 932                         "type='table'"
 933                 );
 934
 935                 $endArray = array();
 936
 937                 foreach ( $result as $table ) {
 938                         $vars = get_object_vars( $table );
 939                         $table = array_pop( $vars );
 940
 941                         if ( !$prefix || strpos( $table, $prefix ) === 0 ) {
 942                                 if ( strpos( $table, 'sqlite_' ) !== 0 ) {
 943                                         $endArray[] = $table;
 944                                 }
 945                         }
 946                 }
 947
 948                 return $endArray;
 949         }
 950 } // end DatabaseSqlite class
 951
 952 /**
 953  * This class allows simple acccess to a SQLite database independently from main database settings
 954  * @ingroup Database
 955  */
 956 class DatabaseSqliteStandalone extends DatabaseSqlite {
 957         public function __construct( $fileName, $flags = 0 ) {
 958                 $this->mFlags = $flags;
 959                 $this->tablePrefix( null );
 960                 $this->openFile( $fileName );
 961         }
 962 }
 963
 964 /**
 965  * @ingroup Database
 966  */
 967 class SQLiteField implements Field {
 968         private $info, $tableName;
 969
 970         function __construct( $info, $tableName ) {
 971                 $this->info = $info;
 972                 $this->tableName = $tableName;
 973         }
 974
 975         function name() {
 976                 return $this->info->name;
 977         }
 978
 979         function tableName() {
 980                 return $this->tableName;
 981         }
 982
 983         function defaultValue() {
 984                 if ( is_string( $this->info->dflt_value ) ) {
 985                         // Typically quoted
 986                         if ( preg_match( '/^\'(.*)\'$', $this->info->dflt_value ) ) {
 987                                 return str_replace( "''", "'", $this->info->dflt_value );
 988                         }
 989                 }
 990
 991                 return $this->info->dflt_value;
 992         }
 993
 994         /**
 995          * @return bool
 996          */
 997         function isNullable() {
 998                 return !$this->info->notnull;
 999         }
1000
1001         function type() {
1002                 return $this->info->type;
1003         }
1004 } // end SQLiteField