includes/DatabaseFunctions.php

   1 <?
   2 include_once( "FulltextStoplist.php" );
   3 include_once( "CacheManager.php" );
   4
   5 define( "DB_READ", -1 );
   6 define( "DB_WRITE", -2 );
   7 define( "DB_LAST", -3 );
   8
   9 $wgLastDatabaseQuery = "";
  10
  11 /* private */ $wgBufferSQLResults = true;
  12 /* private */ $wgIgnoreSQLErrors = false;
  13
  14 function wfGetDB( $altuser = "", $altpassword = "", $altserver = "", $altdb = "" )
  15 {
  16         global $wgDBserver, $wgDBuser, $wgDBpassword;
  17         global $wgDBname, $wgDBconnection, $wgEmergencyContact;
  18
  19         $noconn = wfMsgNoDB( "noconnect", $wgDBserver );
  20         $nodb = wfMsgNoDB( "nodb", $wgDBname );
  21
  22         $helpme = "\n<p>If this error persists after reloading and clearing " .
  23           "your browser cache, please notify the <a href=\"mailto:" .
  24           $wgEmergencyContact . "\">Wikipedia developers</a>.</p>";
  25
  26         if ( $altuser != "" ) {
  27                 $serve = ($altserver ? $altserver : $wgDBserver );
  28                 $db = ($altdb ? $altdb : $wgDBname );
  29                 $wgDBconnection = mysql_connect( $serve, $altuser, $altpassword )
  30                         or die( "bad sql user" );
  31                 mysql_select_db( $db, $wgDBconnection ) or die(
  32                   htmlspecialchars(mysql_error()) );
  33         }
  34
  35         if ( ! $wgDBconnection ) {
  36                 @$wgDBconnection = mysql_connect( $wgDBserver, $wgDBuser, $wgDBpassword )
  37                         or wfEmergencyAbort();
  38
  39                 @mysql_select_db( $wgDBname, $wgDBconnection )
  40                         or wfEmergencyAbort();
  41         }
  42         # mysql_ping( $wgDBconnection );
  43         return $wgDBconnection;
  44 }
  45
  46 /* Call this function if we couldn't contact the database...
  47    We'll try to use the cache to display something in the meantime */
  48 function wfEmergencyAbort( $msg = "" ) {
  49         global $wgTitle, $wgUseFileCache, $title, $wgOutputEncoding;
  50
  51         header( "Content-type: text/html; charset=$wgOutputEncoding" );
  52         if($msg == "") $msg = wfMsgNoDB( "noconnect" );
  53         $text = $msg;
  54
  55         if($wgUseFileCache) {
  56                 if($wgTitle) {
  57                         $t =& $wgTitle;
  58                 } else {
  59                         if($title) {
  60                                 $t = Title::newFromURL( $title );
  61                         } else {
  62                                 $t = Title::newFromText( wfMsgNoDB( "mainpage" ) );
  63                         }
  64                 }
  65
  66                 $cache = new CacheManager( $t );
  67                 if( $cache->isFileCached() ) {
  68                         $msg = "<p style='color: red'><b>$msg<br>\n" .
  69                                 wfMsgNoDB( "cachederror" ) . "</b></p>\n";
  70
  71                         $tag = "<div id='article'>";
  72                         $text = str_replace(
  73                                 $tag,
  74                                 $tag . $msg,
  75                                 $cache->fetchPageText() );
  76                 }
  77         }
  78
  79         /* Don't cache error pages!  They cause no end of trouble... */
  80         header( "Cache-control: none" );
  81         header( "Pragma: nocache" );
  82         echo $text;
  83         wfAbruptExit();
  84 }
  85
  86 # $db: DB_READ  = -1    read from slave (or only server)
  87 #      DB_WRITE = -2    write to master (or only server)
  88 #      0,1,2,...        query a database with a specific index
  89 # Replication is not actually implemented just yet
  90 function wfQuery( $sql, $db, $fname = "" )
  91 {
  92         global $wgLastDatabaseQuery, $wgOut, $wgDebugDumpSql, $wgBufferSQLResults,
  93                 $wgIgnoreSQLErrors, $wgProfiling;
  94
  95         if ( $wgProfiling ) {
  96                 # wfGeneralizeSQL will probably cut down the query to reasonable
  97                 # logging size most of the time. The substr is really just a sanity check.
  98                 $profName = "wfQuery: " . substr( wfGeneralizeSQL( $sql ), 0, 255 );
  99                 wfProfileIn( $profName );
 100         }
 101
 102         if ( !is_numeric( $db ) ) {
 103                 # Someone has tried to call this the old way
 104                 $wgOut->fatalError( wfMsgNoDB( "wrong_wfQuery_params", $db, $sql ) );
 105         }
 106
 107         $wgLastDatabaseQuery = $sql;
 108
 109         if( $wgDebugDumpSql ) {
 110                 $sqlx = substr( $sql, 0, 500 );
 111                 $sqlx = wordwrap(strtr($sqlx,"\t\n","  "));
 112                 wfDebug( "SQL: $sqlx\n" );
 113         }
 114
 115         $conn = wfGetDB();
 116         if( $wgBufferSQLResults ) {
 117                 $ret = mysql_query( $sql, $conn );
 118         } else {
 119                 $ret = mysql_unbuffered_query( $sql, $conn );
 120         }
 121
 122         if ( false === $ret ) {
 123                 if( $wgIgnoreSQLErrors ) {
 124                         wfDebug("SQL ERROR (ignored): " . mysql_error( $conn ) . "\n");
 125                 } else {
 126                         wfDebug("SQL ERROR: " . mysql_error( $conn ) . "\n");
 127                         $wgOut->databaseError( $fname ); // calls wfAbruptExit()
 128                 }
 129         }
 130
 131         if ( $wgProfiling ) {
 132                 wfProfileOut( $profName );
 133         }
 134         return $ret;
 135 }
 136
 137 # Turns buffering of SQL result sets on (true) or off (false). Default is
 138 # "on" and it should not be changed without good reasons.
 139 # Returns the previous state.
 140
 141 function wfBufferSQLResults( $newstate ){
 142         global $wgBufferSQLResults;
 143         $oldstate = $wgBufferSQLResults;
 144         $wgBufferSQLResults = $newstate;
 145         return $oldstate;
 146 }
 147
 148 # Turns on (false) or off (true) the automatic generation and sending
 149 # of a "we're sorry, but there has been a database error" page on
 150 # database errors. Default is on (false). When turned off, the
 151 # code should use wfLastErrno() and wfLastError() to handle the
 152 # situation as appropriate.
 153 # Returns the previous state.
 154
 155 function wfIgnoreSQLErrors( $newstate ){
 156         global $wgIgnoreSQLErrors;
 157         $oldstate = $wgIgnoreSQLErrors;
 158         $wgIgnoreSQLErrors = $newstate;
 159         return $oldstate;
 160 }
 161
 162 function wfFreeResult( $res ) { mysql_free_result( $res ); }
 163 function wfFetchObject( $res ) { return mysql_fetch_object( $res ); }
 164 function wfNumRows( $res ) { return mysql_num_rows( $res ); }
 165 function wfNumFields( $res ) { return mysql_num_fields( $res ); }
 166 function wfFieldName( $res, $n ) { return mysql_field_name( $res, $n ); }
 167 function wfInsertId() { return mysql_insert_id( wfGetDB() ); }
 168 function wfDataSeek( $res, $row ) { return mysql_data_seek( $res, $row ); }
 169 function wfLastErrno() { return mysql_errno(); }
 170 function wfLastError() { return mysql_error(); }
 171 function wfAffectedRows() { return mysql_affected_rows( wfGetDB() ); }
 172
 173 function wfLastDBquery()
 174 {
 175         global $wgLastDatabaseQuery;
 176         return $wgLastDatabaseQuery;
 177 }
 178
 179 function wfSetSQL( $table, $var, $value, $cond )
 180 {
 181         $sql = "UPDATE $table SET $var = '" .
 182           wfStrencode( $value ) . "' WHERE ($cond)";
 183         wfQuery( $sql, DB_WRITE, "wfSetSQL" );
 184 }
 185
 186 function wfGetSQL( $table, $var, $cond )
 187 {
 188         $sql = "SELECT $var FROM $table WHERE ($cond)";
 189         $result = wfQuery( $sql, DB_READ, "wfGetSQL" );
 190
 191         $ret = "";
 192         if ( mysql_num_rows( $result ) > 0 ) {
 193                 $s = mysql_fetch_object( $result );
 194                 $ret = $s->$var;
 195                 mysql_free_result( $result );
 196         }
 197         return $ret;
 198 }
 199
 200 function wfStrencode( $s )
 201 {
 202         return addslashes( $s );
 203 }
 204
 205 # Ideally we'd be using actual time fields in the db
 206 function wfTimestamp2Unix( $ts ) {
 207         return gmmktime( ( (int)substr( $ts, 8, 2) ),
 208                   (int)substr( $ts, 10, 2 ), (int)substr( $ts, 12, 2 ),
 209                   (int)substr( $ts, 4, 2 ), (int)substr( $ts, 6, 2 ),
 210                   (int)substr( $ts, 0, 4 ) );
 211 }
 212
 213 function wfUnix2Timestamp( $unixtime ) {
 214         return gmdate( "YmdHis", $unixtime );
 215 }
 216
 217 function wfTimestampNow() {
 218         # return NOW
 219         return gmdate( "YmdHis" );
 220 }
 221
 222 # Sorting hack for MySQL 3, which doesn't use index sorts for DESC
 223 function wfInvertTimestamp( $ts ) {
 224         return strtr(
 225                 $ts,
 226                 "0123456789",
 227                 "9876543210"
 228         );
 229 }
 230
 231 # Removes most variables from an SQL query and replaces them with X or N for numbers.
 232 # It's only slightly flawed. Don't use for anything important.
 233 function wfGeneralizeSQL( $sql )
 234 {
 235         # This does the same as the regexp below would do, but in such a way
 236         # as to avoid crashing php on some large strings.
 237         # $sql = preg_replace ( "/'([^\\\\']|\\\\.)*'|\"([^\\\\\"]|\\\\.)*\"/", "'X'", $sql);
 238
 239         $sql = str_replace ( "\\\\", "", $sql);
 240         $sql = str_replace ( "\\'", "", $sql);
 241         $sql = str_replace ( "\\\"", "", $sql);
 242         $sql = preg_replace ("/'.*'/s", "'X'", $sql);
 243         $sql = preg_replace ('/".*"/s', "'X'", $sql);
 244
 245         # All newlines, tabs, etc replaced by single space
 246         $sql = preg_replace ( "/\s+/", " ", $sql);
 247
 248         # All numbers => N
 249         $sql = preg_replace ('/-?[0-9]+/s', "N", $sql);
 250
 251         return $sql;
 252 }
 253
 254 function wfFieldExists( $table, $field )
 255 {
 256         $fname = "wfFieldExists";
 257         $res = wfQuery( "DESCRIBE $table", DB_READ, $fname );
 258         $found = false;
 259
 260         while ( $row = wfFetchObject( $res ) ) {
 261                 if ( $row->Field == $field ) {
 262                         $found = true;
 263                         break;
 264                 }
 265         }
 266         return $found;
 267 }
 268
 269 function wfIndexExists( $table, $index )
 270 {
 271         global $wgDBname;
 272         $fname = "wfIndexExists";
 273         $sql = "SHOW INDEXES FROM $table";
 274         $res = wfQuery( $sql, DB_READ, $fname );
 275         $found = false;
 276         while ( $row = wfFetchObject( $res ) ) {
 277                 if ( $row->Key_name == $index ) {
 278                         $found = true;
 279                         break;
 280                 }
 281         }
 282         return $found;
 283 }
 284 ?>