includes/Database.php

   1 <?php
   2 # $Id$
   3 # This file deals with MySQL interface functions
   4 # and query specifics/optimisations
   5 #
   6 require_once( "CacheManager.php" );
   7
   8 define( "LIST_COMMA", 0 );
   9 define( "LIST_AND", 1 );
  10 define( "LIST_SET", 2 );
  11
  12 class Database {
  13
  14 #------------------------------------------------------------------------------
  15 # Variables
  16 #------------------------------------------------------------------------------
  17         /* private */ var $mLastQuery = "";
  18         /* private */ var $mBufferResults = true;
  19         /* private */ var $mIgnoreErrors = false;
  20
  21         /* private */ var $mServer, $mUser, $mPassword, $mConn, $mDBname;
  22         /* private */ var $mOut, $mDebug, $mOpened = false;
  23
  24         /* private */ var $mFailFunction;
  25
  26 #------------------------------------------------------------------------------
  27 # Accessors
  28 #------------------------------------------------------------------------------
  29         # Set functions
  30         # These set a variable and return the previous state
  31
  32         # Fail function, takes a Database as a parameter
  33         # Set to false for default, 1 for ignore errors
  34         function setFailFunction( $function ) { return wfSetVar( $this->mFailFunction, $function ); }
  35
  36         # Output page, used for reporting errors
  37         # FALSE means discard output
  38         function &setOutputPage( &$out ) { $this->mOut =& $out; }
  39
  40         # Boolean, controls output of large amounts of debug information
  41         function setDebug( $debug ) { return wfSetVar( $this->mDebug, $debug ); }
  42
  43         # Turns buffering of SQL result sets on (true) or off (false). Default is
  44         # "on" and it should not be changed without good reasons.
  45         function setBufferResults( $buffer ) { return wfSetVar( $this->mBufferResults, $buffer ); }
  46
  47         # Turns on (false) or off (true) the automatic generation and sending
  48         # of a "we're sorry, but there has been a database error" page on
  49         # database errors. Default is on (false). When turned off, the
  50         # code should use wfLastErrno() and wfLastError() to handle the
  51         # situation as appropriate.
  52         function setIgnoreErrors( $ignoreErrors ) { return wfSetVar( $this->mIgnoreErrors, $ignoreErrors ); }
  53
  54         # Get functions
  55
  56         function lastQuery() { return $this->mLastQuery; }
  57         function isOpen() { return $this->mOpened; }
  58
  59 #------------------------------------------------------------------------------
  60 # Other functions
  61 #------------------------------------------------------------------------------
  62
  63         function Database()
  64         {
  65                 global $wgOut;
  66                 # Can't get a reference if it hasn't been set yet
  67                 if ( !isset( $wgOut ) ) {
  68                         $wgOut = NULL;
  69                 }
  70                 $this->mOut =& $wgOut;
  71
  72         }
  73
  74         /* static */ function newFromParams( $server, $user, $password, $dbName,
  75                 $failFunction = false, $debug = false, $bufferResults = true, $ignoreErrors = false )
  76         {
  77                 $db = new Database;
  78                 $db->mFailFunction = $failFunction;
  79                 $db->mIgnoreErrors = $ignoreErrors;
  80                 $db->mDebug = $debug;
  81                 $db->mBufferResults = $bufferResults;
  82                 $db->open( $server, $user, $password, $dbName );
  83                 return $db;
  84         }
  85
  86         # Usually aborts on failure
  87         # If the failFunction is set to a non-zero integer, returns success
  88         function open( $server, $user, $password, $dbName )
  89         {
  90                 global $wgEmergencyContact;
  91
  92                 $this->close();
  93                 $this->mServer = $server;
  94                 $this->mUser = $user;
  95                 $this->mPassword = $password;
  96                 $this->mDBname = $dbName;
  97
  98                 $success = false;
  99
 100                 @$this->mConn = mysql_connect( $server, $user, $password );
 101                 if ( $dbName != "" ) {
 102                         if ( $this->mConn !== false ) {
 103                                 $success = @mysql_select_db( $dbName, $this->mConn );
 104                                 if ( !$success ) {
 105                                         wfDebug( "Error selecting database \"$dbName\": " . $this->lastError() . "\n" );
 106                                 }
 107                         } else {
 108                                 wfDebug( "DB connection error\n" );
 109                                 wfDebug( "Server: $server, User: $user, Password: " .
 110                                         substr( $password, 0, 3 ) . "...\n" );
 111                                 $success = false;
 112                         }
 113                 } else {
 114                         # Delay USE query
 115                         $success = !!$this->mConn;
 116                 }
 117
 118                 if ( !$success ) {
 119                         $this->reportConnectionError();
 120                         $this->close();
 121                 }
 122                 $this->mOpened = $success;
 123                 return $success;
 124         }
 125
 126         # Closes a database connection, if it is open
 127         # Returns success, true if already closed
 128         function close()
 129         {
 130                 $this->mOpened = false;
 131                 if ( $this->mConn ) {
 132                         return mysql_close( $this->mConn );
 133                 } else {
 134                         return true;
 135                 }
 136         }
 137
 138         /* private */ function reportConnectionError( $msg = "")
 139         {
 140                 if ( $this->mFailFunction ) {
 141                         if ( !is_int( $this->mFailFunction ) ) {
 142                                 $ff = $this->mFailFunction;
 143                                 $ff( $this, mysql_error() );
 144                         }
 145                 } else {
 146                         wfEmergencyAbort( $this, mysql_error() );
 147                 }
 148         }
 149
 150         # Usually aborts on failure
 151         # If errors are explicitly ignored, returns success
 152         function query( $sql, $fname = "" )
 153         {
 154                 global $wgProfiling;
 155
 156                 if ( $wgProfiling ) {
 157                         # generalizeSQL will probably cut down the query to reasonable
 158                         # logging size most of the time. The substr is really just a sanity check.
 159                         $profName = "query: " . substr( Database::generalizeSQL( $sql ), 0, 255 );
 160                         wfProfileIn( $profName );
 161                 }
 162
 163                 $this->mLastQuery = $sql;
 164
 165                 if ( $this->mDebug ) {
 166                         $sqlx = substr( $sql, 0, 500 );
 167                         $sqlx = wordwrap(strtr($sqlx,"\t\n","  "));
 168                         wfDebug( "SQL: $sqlx\n" );
 169                 }
 170                 if( $this->mBufferResults ) {
 171                         $ret = mysql_query( $sql, $this->mConn );
 172                 } else {
 173                         $ret = mysql_unbuffered_query( $sql, $this->mConn );
 174                 }
 175
 176                 if ( false === $ret ) {
 177                         $error = mysql_error( $this->mConn );
 178                         $errno = mysql_errno( $this->mConn );
 179                         if( $this->mIgnoreErrors ) {
 180                                 wfDebug("SQL ERROR (ignored): " . $error . "\n");
 181                         } else {
 182                                 wfDebug("SQL ERROR: " . $error . "\n");
 183                                 if ( $this->mOut ) {
 184                                         // this calls wfAbruptExit()
 185                                         $this->mOut->databaseError( $fname, $sql, $error, $errno );
 186                                 }
 187                         }
 188                 }
 189
 190                 if ( $wgProfiling ) {
 191                         wfProfileOut( $profName );
 192                 }
 193                 return $ret;
 194         }
 195
 196         function freeResult( $res ) {
 197                 if ( !@mysql_free_result( $res ) ) {
 198                         wfDebugDieBacktrace( "Unable to free MySQL result\n" );
 199                 }
 200         }
 201         function fetchObject( $res ) {
 202                 @$row = mysql_fetch_object( $res );
 203                 # FIXME: HACK HACK HACK HACK debug
 204                 if( mysql_errno() ) {
 205                         wfDebugDieBacktrace( "SQL error: " . htmlspecialchars( mysql_error() ) );
 206                 }
 207                 return $row;
 208         }
 209
 210         function fetchRow( $res ) {
 211                 @$row = mysql_fetch_array( $res );
 212                 if (mysql_errno() ) {
 213                         wfDebugDieBacktrace( "SQL error: " . htmlspecialchars( mysql_error() ) );
 214                 }
 215                 return $row;
 216         }
 217
 218         function numRows( $res ) {
 219                 @$n = mysql_num_rows( $res );
 220                 if( mysql_errno() ) {
 221                         wfDebugDieBacktrace( "SQL error: " . htmlspecialchars( mysql_error() ) );
 222                 }
 223                 return $n;
 224         }
 225         function numFields( $res ) { return mysql_num_fields( $res ); }
 226         function fieldName( $res, $n ) { return mysql_field_name( $res, $n ); }
 227         function insertId() { return mysql_insert_id( $this->mConn ); }
 228         function dataSeek( $res, $row ) { return mysql_data_seek( $res, $row ); }
 229         function lastErrno() { return mysql_errno(); }
 230         function lastError() { return mysql_error(); }
 231         function affectedRows() { return mysql_affected_rows( $this->mConn ); }
 232
 233         # Simple UPDATE wrapper
 234         # Usually aborts on failure
 235         # If errors are explicitly ignored, returns success
 236         function set( $table, $var, $value, $cond, $fname = "Database::set" )
 237         {
 238                 $sql = "UPDATE $table SET $var = '" .
 239                   wfStrencode( $value ) . "' WHERE ($cond)";
 240                 return !!$this->query( $sql, DB_WRITE, $fname );
 241         }
 242
 243         # Simple SELECT wrapper, returns a single field, input must be encoded
 244         # Usually aborts on failure
 245         # If errors are explicitly ignored, returns FALSE on failure
 246         function get( $table, $var, $cond, $fname = "Database::get" )
 247         {
 248                 $sql = "SELECT $var FROM $table WHERE ($cond)";
 249                 $result = $this->query( $sql, DB_READ, $fname );
 250
 251                 $ret = "";
 252                 if ( mysql_num_rows( $result ) > 0 ) {
 253                         $s = mysql_fetch_object( $result );
 254                         $ret = $s->$var;
 255                         mysql_free_result( $result );
 256                 }
 257                 return $ret;
 258         }
 259
 260         # More complex SELECT wrapper, single row only
 261         # Aborts or returns FALSE on error
 262         # Takes an array of selected variables, and a condition map, which is ANDed
 263         # e.g. getArray( "cur", array( "cur_id" ), array( "cur_namespace" => 0, "cur_title" => "Astronomy" ) )
 264         #   would return an object where $obj->cur_id is the ID of the Astronomy article
 265         function getArray( $table, $vars, $conds, $fname = "Database::getArray" )
 266         {
 267                 $vars = implode( ",", $vars );
 268                 $where = Database::makeList( $conds, LIST_AND );
 269                 $sql = "SELECT $vars FROM $table WHERE $where LIMIT 1";
 270                 $res = $this->query( $sql, $fname );
 271                 if ( $res === false || !$this->numRows( $res ) ) {
 272                         return false;
 273                 }
 274                 $obj = $this->fetchObject( $res );
 275                 $this->freeResult( $res );
 276                 return $obj;
 277         }
 278
 279         # Removes most variables from an SQL query and replaces them with X or N for numbers.
 280         # It's only slightly flawed. Don't use for anything important.
 281         /* static */ function generalizeSQL( $sql )
 282         {
 283                 # This does the same as the regexp below would do, but in such a way
 284                 # as to avoid crashing php on some large strings.
 285                 # $sql = preg_replace ( "/'([^\\\\']|\\\\.)*'|\"([^\\\\\"]|\\\\.)*\"/", "'X'", $sql);
 286
 287                 $sql = str_replace ( "\\\\", "", $sql);
 288                 $sql = str_replace ( "\\'", "", $sql);
 289                 $sql = str_replace ( "\\\"", "", $sql);
 290                 $sql = preg_replace ("/'.*'/s", "'X'", $sql);
 291                 $sql = preg_replace ('/".*"/s', "'X'", $sql);
 292
 293                 # All newlines, tabs, etc replaced by single space
 294                 $sql = preg_replace ( "/\s+/", " ", $sql);
 295
 296                 # All numbers => N
 297                 $sql = preg_replace ('/-?[0-9]+/s', "N", $sql);
 298
 299                 return $sql;
 300         }
 301
 302         # Determines whether a field exists in a table
 303         # Usually aborts on failure
 304         # If errors are explicitly ignored, returns NULL on failure
 305         function fieldExists( $table, $field, $fname = "Database::fieldExists" )
 306         {
 307                 $res = $this->query( "DESCRIBE $table", DB_READ, $fname );
 308                 if ( !$res ) {
 309                         return NULL;
 310                 }
 311
 312                 $found = false;
 313
 314                 while ( $row = $this->fetchObject( $res ) ) {
 315                         if ( $row->Field == $field ) {
 316                                 $found = true;
 317                                 break;
 318                         }
 319                 }
 320                 return $found;
 321         }
 322
 323         # Determines whether an index exists
 324         # Usually aborts on failure
 325         # If errors are explicitly ignored, returns NULL on failure
 326         function indexExists( $table, $index, $fname = "Database::indexExists" )
 327         {
 328                 # SHOW INDEX works in MySQL 3.23.58, but SHOW INDEXES does not.
 329                 # SHOW INDEX should work for 3.x and up:
 330                 # http://dev.mysql.com/doc/mysql/en/SHOW_INDEX.html
 331                 $sql = "SHOW INDEX FROM $table";
 332                 $res = $this->query( $sql, DB_READ, $fname );
 333                 if ( !$res ) {
 334                         return NULL;
 335                 }
 336
 337                 $found = false;
 338
 339                 while ( $row = $this->fetchObject( $res ) ) {
 340                         if ( $row->Key_name == $index ) {
 341                                 $found = true;
 342                                 break;
 343                         }
 344                 }
 345                 return $found;
 346         }
 347
 348         function tableExists( $table )
 349         {
 350                 $old = $this->mIgnoreErrors;
 351                 $this->mIgnoreErrors = true;
 352                 $res = $this->query( "SELECT 1 FROM $table LIMIT 1" );
 353                 $this->mIgnoreErrors = $old;
 354                 if( $res ) {
 355                         $this->freeResult( $res );
 356                         return true;
 357                 } else {
 358                         return false;
 359                 }
 360         }
 361
 362         function fieldInfo( $table, $field )
 363         {
 364                 $res = $this->query( "SELECT * FROM $table LIMIT 1" );
 365                 $n = mysql_num_fields( $res );
 366                 for( $i = 0; $i < $n; $i++ ) {
 367                         $meta = mysql_fetch_field( $res, $i );
 368                         if( $field == $meta->name ) {
 369                                 return $meta;
 370                         }
 371                 }
 372                 return false;
 373         }
 374
 375         # INSERT wrapper, inserts an array into a table
 376         # Keys are field names, values are values
 377         # Usually aborts on failure
 378         # If errors are explicitly ignored, returns success
 379         function insertArray( $table, $a, $fname = "Database::insertArray" )
 380         {
 381                 $sql1 = "INSERT INTO $table (";
 382                 $sql2 = "VALUES (" . Database::makeList( $a );
 383                 $first = true;
 384                 foreach ( $a as $field => $value ) {
 385                         if ( !$first ) {
 386                                 $sql1 .= ",";
 387                         }
 388                         $first = false;
 389                         $sql1 .= $field;
 390                 }
 391                 $sql = "$sql1) $sql2)";
 392                 return !!$this->query( $sql, $fname );
 393         }
 394
 395         # A cross between insertArray and getArray, takes a condition array and a SET array
 396         function updateArray( $table, $values, $conds, $fname = "Database::updateArray" )
 397         {
 398                 $sql = "UPDATE $table SET " . $this->makeList( $values, LIST_SET );
 399                 $sql .= " WHERE " . $this->makeList( $conds, LIST_AND );
 400                 $this->query( $sql, $fname );
 401         }
 402
 403         # Makes a wfStrencoded list from an array
 404         # $mode: LIST_COMMA - comma separated, no field names
 405         #        LIST_AND   - ANDed WHERE clause (without the WHERE)
 406         #        LIST_SET   - comma separated with field names, like a SET clause
 407         /* static */ function makeList( $a, $mode = LIST_COMMA )
 408         {
 409                 $first = true;
 410                 $list = "";
 411                 foreach ( $a as $field => $value ) {
 412                         if ( !$first ) {
 413                                 if ( $mode == LIST_AND ) {
 414                                         $list .= " AND ";
 415                                 } else {
 416                                         $list .= ",";
 417                                 }
 418                         } else {
 419                                 $first = false;
 420                         }
 421                         if ( $mode == LIST_AND || $mode == LIST_SET ) {
 422                                 $list .= "$field=";
 423                         }
 424                         if ( !is_numeric( $value ) ) {
 425                                 $list .= "'" . wfStrencode( $value ) . "'";
 426                         } else {
 427                                 $list .= $value;
 428                         }
 429                 }
 430                 return $list;
 431         }
 432
 433         function selectDB( $db )
 434         {
 435                 $this->mDBname = $db;
 436                 mysql_select_db( $db, $this->mConn );
 437         }
 438
 439         function startTimer( $timeout )
 440         {
 441                 global $IP;
 442
 443                 $tid = mysql_thread_id( $this->mConn );
 444                 exec( "php $IP/killthread.php $timeout $tid &>/dev/null &" );
 445         }
 446
 447         function stopTimer()
 448         {
 449         }
 450
 451 }
 452
 453 #------------------------------------------------------------------------------
 454 # Global functions
 455 #------------------------------------------------------------------------------
 456
 457 /* Standard fail function, called by default when a connection cannot be established
 458    Displays the file cache if possible */
 459 function wfEmergencyAbort( &$conn, $error ) {
 460         global $wgTitle, $wgUseFileCache, $title, $wgInputEncoding, $wgSiteNotice, $wgOutputEncoding;
 461
 462         if( !headers_sent() ) {
 463                 header( "HTTP/1.0 500 Internal Server Error" );
 464                 header( "Content-type: text/html; charset=$wgOutputEncoding" );
 465                 /* Don't cache error pages!  They cause no end of trouble... */
 466                 header( "Cache-control: none" );
 467                 header( "Pragma: nocache" );
 468         }
 469         $msg = $wgSiteNotice;
 470         if($msg == "") $msg = wfMsgNoDB( "noconnect", $error );
 471         $text = $msg;
 472
 473         if($wgUseFileCache) {
 474                 if($wgTitle) {
 475                         $t =& $wgTitle;
 476                 } else {
 477                         if($title) {
 478                                 $t = Title::newFromURL( $title );
 479                         } elseif (@$_REQUEST['search']) {
 480                                 $search = $_REQUEST['search'];
 481                                 echo wfMsgNoDB( "searchdisabled" );
 482                                 echo wfMsgNoDB( "googlesearch", htmlspecialchars( $search ), $wgInputEncoding );
 483                                 wfAbruptExit();
 484                         } else {
 485                                 $t = Title::newFromText( wfMsgNoDB( "mainpage" ) );
 486                         }
 487                 }
 488
 489                 $cache = new CacheManager( $t );
 490                 if( $cache->isFileCached() ) {
 491                         $msg = "<p style='color: red'><b>$msg<br />\n" .
 492                                 wfMsgNoDB( "cachederror" ) . "</b></p>\n";
 493
 494                         $tag = "<div id='article'>";
 495                         $text = str_replace(
 496                                 $tag,
 497                                 $tag . $msg,
 498                                 $cache->fetchPageText() );
 499                 }
 500         }
 501
 502         echo $text;
 503         wfAbruptExit();
 504 }
 505
 506 function wfStrencode( $s )
 507 {
 508         return addslashes( $s );
 509 }
 510
 511 # Ideally we'd be using actual time fields in the db
 512 function wfTimestamp2Unix( $ts ) {
 513         return gmmktime( ( (int)substr( $ts, 8, 2) ),
 514                   (int)substr( $ts, 10, 2 ), (int)substr( $ts, 12, 2 ),
 515                   (int)substr( $ts, 4, 2 ), (int)substr( $ts, 6, 2 ),
 516                   (int)substr( $ts, 0, 4 ) );
 517 }
 518
 519 function wfUnix2Timestamp( $unixtime ) {
 520         return gmdate( "YmdHis", $unixtime );
 521 }
 522
 523 function wfTimestampNow() {
 524         # return NOW
 525         return gmdate( "YmdHis" );
 526 }
 527
 528 # Sorting hack for MySQL 3, which doesn't use index sorts for DESC
 529 function wfInvertTimestamp( $ts ) {
 530         return strtr(
 531                 $ts,
 532                 "0123456789",
 533                 "9876543210"
 534         );
 535 }
 536
 537 function wfLimitResult( $limit, $offset ) {
 538         return " LIMIT ".(is_numeric($offset)?"{$offset},":"")."{$limit} ";
 539 }
 540
 541 ?>