includes/db/DatabaseMysql.php

   1 <?php
   2 /**
   3  * Database abstraction object for mySQL
   4  * Inherit all methods and properties of Database::Database()
   5  *
   6  * @ingroup Database
   7  * @see Database
   8  */
   9 class DatabaseMysql extends DatabaseBase {
  10         /*private*/ function doQuery( $sql ) {
  11                 if( $this->bufferResults() ) {
  12                         $ret = mysql_query( $sql, $this->mConn );
  13                 } else {
  14                         $ret = mysql_unbuffered_query( $sql, $this->mConn );
  15                 }
  16                 return $ret;
  17         }
  18
  19         function open( $server, $user, $password, $dbName ) {
  20                 global $wgAllDBsAreLocalhost;
  21                 wfProfileIn( __METHOD__ );
  22
  23                 # Test for missing mysql.so
  24                 # First try to load it
  25                 if (!@extension_loaded('mysql')) {
  26                         @dl('mysql.so');
  27                 }
  28
  29                 # Fail now
  30                 # Otherwise we get a suppressed fatal error, which is very hard to track down
  31                 if ( !function_exists( 'mysql_connect' ) ) {
  32                         throw new DBConnectionError( $this, "MySQL functions missing, have you compiled PHP with the --with-mysql option?\n" );
  33                 }
  34
  35                 # Debugging hack -- fake cluster
  36                 if ( $wgAllDBsAreLocalhost ) {
  37                         $realServer = 'localhost';
  38                 } else {
  39                         $realServer = $server;
  40                 }
  41                 $this->close();
  42                 $this->mServer = $server;
  43                 $this->mUser = $user;
  44                 $this->mPassword = $password;
  45                 $this->mDBname = $dbName;
  46
  47                 $success = false;
  48
  49                 wfProfileIn("dbconnect-$server");
  50
  51                 # The kernel's default SYN retransmission period is far too slow for us,
  52                 # so we use a short timeout plus a manual retry. Retrying means that a small
  53                 # but finite rate of SYN packet loss won't cause user-visible errors.
  54                 $this->mConn = false;
  55                 if ( ini_get( 'mysql.connect_timeout' ) <= 3 ) {
  56                         $numAttempts = 2;
  57                 } else {
  58                         $numAttempts = 1;
  59                 }
  60                 $this->installErrorHandler();
  61                 for ( $i = 0; $i < $numAttempts && !$this->mConn; $i++ ) {
  62                         if ( $i > 1 ) {
  63                                 usleep( 1000 );
  64                         }
  65                         if ( $this->mFlags & DBO_PERSISTENT ) {
  66                                 $this->mConn = mysql_pconnect( $realServer, $user, $password );
  67                         } else {
  68                                 # Create a new connection...
  69                                 $this->mConn = mysql_connect( $realServer, $user, $password, true );
  70                         }
  71                         if ($this->mConn === false) {
  72                                 #$iplus = $i + 1;
  73                                 #wfLogDBError("Connect loop error $iplus of $max ($server): " . mysql_errno() . " - " . mysql_error()."\n");
  74                         }
  75                 }
  76                 $phpError = $this->restoreErrorHandler();
  77                 # Always log connection errors
  78                 if ( !$this->mConn ) {
  79                         $error = $this->lastError();
  80                         if ( !$error ) {
  81                                 $error = $phpError;
  82                         }
  83                         wfLogDBError( "Error connecting to {$this->mServer}: $error\n" );
  84                         wfDebug( "DB connection error\n" );
  85                         wfDebug( "Server: $server, User: $user, Password: " .
  86                                 substr( $password, 0, 3 ) . "..., error: " . mysql_error() . "\n" );
  87                         $success = false;
  88                 }
  89
  90                 wfProfileOut("dbconnect-$server");
  91
  92                 if ( $dbName != '' && $this->mConn !== false ) {
  93                         $success = @/**/mysql_select_db( $dbName, $this->mConn );
  94                         if ( !$success ) {
  95                                 $error = "Error selecting database $dbName on server {$this->mServer} " .
  96                                         "from client host " . wfHostname() . "\n";
  97                                 wfLogDBError(" Error selecting database $dbName on server {$this->mServer} \n");
  98                                 wfDebug( $error );
  99                         }
 100                 } else {
 101                         # Delay USE query
 102                         $success = (bool)$this->mConn;
 103                 }
 104
 105                 if ( $success ) {
 106                         $version = $this->getServerVersion();
 107                         if ( version_compare( $version, '4.1' ) >= 0 ) {
 108                                 // Tell the server we're communicating with it in UTF-8.
 109                                 // This may engage various charset conversions.
 110                                 global $wgDBmysql5;
 111                                 if( $wgDBmysql5 ) {
 112                                         $this->query( 'SET NAMES utf8', __METHOD__ );
 113                                 }
 114                                 // Turn off strict mode
 115                                 $this->query( "SET sql_mode = ''", __METHOD__ );
 116                         }
 117
 118                         // Turn off strict mode if it is on
 119                 } else {
 120                         $this->reportConnectionError( $phpError );
 121                 }
 122
 123                 $this->mOpened = $success;
 124                 wfProfileOut( __METHOD__ );
 125                 return $success;
 126         }
 127
 128         function close() {
 129                 $this->mOpened = false;
 130                 if ( $this->mConn ) {
 131                         if ( $this->trxLevel() ) {
 132                                 $this->immediateCommit();
 133                         }
 134                         return mysql_close( $this->mConn );
 135                 } else {
 136                         return true;
 137                 }
 138         }
 139
 140         function freeResult( $res ) {
 141                 if ( $res instanceof ResultWrapper ) {
 142                         $res = $res->result;
 143                 }
 144                 if ( !@/**/mysql_free_result( $res ) ) {
 145                         throw new DBUnexpectedError( $this, "Unable to free MySQL result" );
 146                 }
 147         }
 148
 149         function fetchObject( $res ) {
 150                 if ( $res instanceof ResultWrapper ) {
 151                         $res = $res->result;
 152                 }
 153                 @/**/$row = mysql_fetch_object( $res );
 154                 if( $this->lastErrno() ) {
 155                         throw new DBUnexpectedError( $this, 'Error in fetchObject(): ' . htmlspecialchars( $this->lastError() ) );
 156                 }
 157                 return $row;
 158         }
 159
 160         function fetchRow( $res ) {
 161                 if ( $res instanceof ResultWrapper ) {
 162                         $res = $res->result;
 163                 }
 164                 @/**/$row = mysql_fetch_array( $res );
 165                 if ( $this->lastErrno() ) {
 166                         throw new DBUnexpectedError( $this, 'Error in fetchRow(): ' . htmlspecialchars( $this->lastError() ) );
 167                 }
 168                 return $row;
 169         }
 170
 171         function numRows( $res ) {
 172                 if ( $res instanceof ResultWrapper ) {
 173                         $res = $res->result;
 174                 }
 175                 @/**/$n = mysql_num_rows( $res );
 176                 if( $this->lastErrno() ) {
 177                         throw new DBUnexpectedError( $this, 'Error in numRows(): ' . htmlspecialchars( $this->lastError() ) );
 178                 }
 179                 return $n;
 180         }
 181
 182         function numFields( $res ) {
 183                 if ( $res instanceof ResultWrapper ) {
 184                         $res = $res->result;
 185                 }
 186                 return mysql_num_fields( $res );
 187         }
 188
 189         function fieldName( $res, $n ) {
 190                 if ( $res instanceof ResultWrapper ) {
 191                         $res = $res->result;
 192                 }
 193                 return mysql_field_name( $res, $n );
 194         }
 195
 196         function insertId() { return mysql_insert_id( $this->mConn ); }
 197
 198         function dataSeek( $res, $row ) {
 199                 if ( $res instanceof ResultWrapper ) {
 200                         $res = $res->result;
 201                 }
 202                 return mysql_data_seek( $res, $row );
 203         }
 204
 205         function lastErrno() {
 206                 if ( $this->mConn ) {
 207                         return mysql_errno( $this->mConn );
 208                 } else {
 209                         return mysql_errno();
 210                 }
 211         }
 212
 213         function lastError() {
 214                 if ( $this->mConn ) {
 215                         # Even if it's non-zero, it can still be invalid
 216                         wfSuppressWarnings();
 217                         $error = mysql_error( $this->mConn );
 218                         if ( !$error ) {
 219                                 $error = mysql_error();
 220                         }
 221                         wfRestoreWarnings();
 222                 } else {
 223                         $error = mysql_error();
 224                 }
 225                 if( $error ) {
 226                         $error .= ' (' . $this->mServer . ')';
 227                 }
 228                 return $error;
 229         }
 230
 231         function affectedRows() { return mysql_affected_rows( $this->mConn ); }
 232
 233         /**
 234          * Estimate rows in dataset
 235          * Returns estimated count, based on EXPLAIN output
 236          * Takes same arguments as Database::select()
 237          */
 238         public function estimateRowCount( $table, $vars='*', $conds='', $fname = 'Database::estimateRowCount', $options = array() ) {
 239                 $options['EXPLAIN'] = true;
 240                 $res = $this->select( $table, $vars, $conds, $fname, $options );
 241                 if ( $res === false )
 242                         return false;
 243                 if ( !$this->numRows( $res ) ) {
 244                         $this->freeResult($res);
 245                         return 0;
 246                 }
 247
 248                 $rows = 1;
 249                 while( $plan = $this->fetchObject( $res ) ) {
 250                         $rows *= $plan->rows > 0 ? $plan->rows : 1; // avoid resetting to zero
 251                 }
 252
 253                 $this->freeResult($res);
 254                 return $rows;
 255         }
 256
 257         function fieldInfo( $table, $field ) {
 258                 $table = $this->tableName( $table );
 259                 $res = $this->query( "SELECT * FROM $table LIMIT 1" );
 260                 $n = mysql_num_fields( $res->result );
 261                 for( $i = 0; $i < $n; $i++ ) {
 262                         $meta = mysql_fetch_field( $res->result, $i );
 263                         if( $field == $meta->name ) {
 264                                 return new MySQLField($meta);
 265                         }
 266                 }
 267                 return false;
 268         }
 269
 270         function selectDB( $db ) {
 271                 $this->mDBname = $db;
 272                 return mysql_select_db( $db, $this->mConn );
 273         }
 274
 275         function strencode( $s ) {
 276                 return mysql_real_escape_string( $s, $this->mConn );
 277         }
 278
 279         function ping() {
 280                 if( !function_exists( 'mysql_ping' ) ) {
 281                         wfDebug( "Tried to call mysql_ping but this is ancient PHP version. Faking it!\n" );
 282                         return true;
 283                 }
 284                 $ping = mysql_ping( $this->mConn );
 285                 if ( $ping ) {
 286                         return true;
 287                 }
 288
 289                 // Need to reconnect manually in MySQL client 5.0.13+
 290                 if ( version_compare( mysql_get_client_info(), '5.0.13', '>=' ) ) {
 291                         mysql_close( $this->mConn );
 292                         $this->mOpened = false;
 293                         $this->mConn = false;
 294                         $this->open( $this->mServer, $this->mUser, $this->mPassword, $this->mDBname );
 295                         return true;
 296                 }
 297                 return false;
 298         }
 299
 300         function getServerVersion() {
 301                 return mysql_get_server_info( $this->mConn );
 302         }
 303
 304         function useIndexClause( $index ) {
 305                 return "FORCE INDEX (" . $this->indexName( $index ) . ")";
 306         }
 307
 308         function lowPriorityOption() {
 309                 return 'LOW_PRIORITY';
 310         }
 311
 312         function getSoftwareLink() {
 313                 return '[http://www.mysql.com/ MySQL]';
 314         }
 315
 316         function standardSelectDistinct() {
 317                 return false;
 318         }
 319
 320         public function setTimeout( $timeout ) {
 321                 $this->query( "SET net_read_timeout=$timeout" );
 322                 $this->query( "SET net_write_timeout=$timeout" );
 323         }
 324
 325         public function lock( $lockName, $method, $timeout = 5 ) {
 326                 $lockName = $this->addQuotes( $lockName );
 327                 $result = $this->query( "SELECT GET_LOCK($lockName, $timeout) AS lockstatus", $method );
 328                 $row = $this->fetchObject( $result );
 329                 $this->freeResult( $result );
 330
 331                 if( $row->lockstatus == 1 ) {
 332                         return true;
 333                 } else {
 334                         wfDebug( __METHOD__." failed to acquire lock\n" );
 335                         return false;
 336                 }
 337         }
 338
 339         public function unlock( $lockName, $method ) {
 340                 $lockName = $this->addQuotes( $lockName );
 341                 $result = $this->query( "SELECT RELEASE_LOCK($lockName) as lockstatus", $method );
 342                 $row = $this->fetchObject( $result );
 343                 return $row->lockstatus;
 344         }
 345
 346         public function lockTables( $read, $write, $method, $lowPriority = true ) {
 347                 $items = array();
 348
 349                 foreach( $write as $table ) {
 350                         $tbl = $this->tableName( $table ) .
 351                                         ( $lowPriority ? ' LOW_PRIORITY' : '' ) .
 352                                         ' WRITE';
 353                         $items[] = $tbl;
 354                 }
 355                 foreach( $read as $table ) {
 356                         $items[] = $this->tableName( $table ) . ' READ';
 357                 }
 358                 $sql = "LOCK TABLES " . implode( ',', $items );
 359                 $this->query( $sql, $method );
 360         }
 361
 362         public function unlockTables( $method ) {
 363                 $this->query( "UNLOCK TABLES", $method );
 364         }
 365
 366         public function setBigSelects( $value = true ) {
 367                 if ( $value === 'default' ) {
 368                         if ( $this->mDefaultBigSelects === null ) {
 369                                 # Function hasn't been called before so it must already be set to the default
 370                                 return;
 371                         } else {
 372                                 $value = $this->mDefaultBigSelects;
 373                         }
 374                 } elseif ( $this->mDefaultBigSelects === null ) {
 375                         $this->mDefaultBigSelects = (bool)$this->selectField( false, '@@sql_big_selects' );
 376                 }
 377                 $encValue = $value ? '1' : '0';
 378                 $this->query( "SET sql_big_selects=$encValue", __METHOD__ );
 379         }
 380
 381
 382         /**
 383          * Determines if the last failure was due to a deadlock
 384          */
 385         function wasDeadlock() {
 386                 return $this->lastErrno() == 1213;
 387         }
 388
 389         /**
 390          * Determines if the last query error was something that should be dealt
 391          * with by pinging the connection and reissuing the query
 392          */
 393         function wasErrorReissuable() {
 394                 return $this->lastErrno() == 2013 || $this->lastErrno() == 2006;
 395         }
 396
 397         /**
 398          * Determines if the last failure was due to the database being read-only.
 399          */
 400         function wasReadOnlyError() {
 401                 return $this->lastErrno() == 1223 ||
 402                         ( $this->lastErrno() == 1290 && strpos( $this->lastError(), '--read-only' ) !== false );
 403         }
 404
 405 }
 406
 407 /**
 408  * Legacy support: Database == DatabaseMysql
 409  */
 410 class Database extends DatabaseMysql {}
 411
 412 class MySQLMasterPos {
 413         var $file, $pos;
 414
 415         function __construct( $file, $pos ) {
 416                 $this->file = $file;
 417                 $this->pos = $pos;
 418         }
 419
 420         function __toString() {
 421                 return "{$this->file}/{$this->pos}";
 422         }
 423 }