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
  13 function wfGetDB( $altuser = "", $altpassword = "", $altserver = "", $altdb = "" )
  14 {
  15         global $wgDBserver, $wgDBuser, $wgDBpassword;
  16         global $wgDBname, $wgDBconnection, $wgEmergencyContact;
  17
  18         $noconn = wfMsgNoDB( "noconnect", $wgDBserver );
  19         $nodb = wfMsgNoDB( "nodb", $wgDBname );
  20
  21         $helpme = "\n<p>If this error persists after reloading and clearing " .
  22           "your browser cache, please notify the <a href=\"mailto:" .
  23           $wgEmergencyContact . "\">Wikipedia developers</a>.</p>";
  24
  25         if ( $altuser != "" ) {
  26                 $serve = ($altserver ? $altserver : $wgDBserver );
  27                 $db = ($altdb ? $altdb : $wgDBname );
  28                 $wgDBconnection = mysql_connect( $serve, $altuser, $altpassword )
  29                         or die( "bad sql user" );
  30                 mysql_select_db( $db, $wgDBconnection ) or die(
  31                   htmlspecialchars(mysql_error()) );
  32         }
  33
  34         if ( ! $wgDBconnection ) {
  35                 @$wgDBconnection = mysql_pconnect( $wgDBserver, $wgDBuser, $wgDBpassword )
  36                         or wfEmergencyAbort();
  37
  38                 if( !mysql_select_db( $wgDBname, $wgDBconnection ) ) {
  39                         /* Persistent connections may become stuck in an unusable state */
  40                         wfDebug( "Persistent connection is broken?\n", true );
  41
  42                         @$wgDBconnection = mysql_connect( $wgDBserver, $wgDBuser, $wgDBpassword )
  43                                 or wfEmergencyAbort();
  44
  45                         @mysql_select_db( $wgDBname, $wgDBconnection )
  46                                 or wfEmergencyAbort();
  47                 }
  48         }
  49         # mysql_ping( $wgDBconnection );
  50         return $wgDBconnection;
  51 }
  52
  53 /* Call this function if we couldn't contact the database...
  54    We'll try to use the cache to display something in the meantime */
  55 function wfEmergencyAbort( $msg = "" ) {
  56         global $wgTitle, $wgUseFileCache, $title, $wgOutputEncoding;
  57
  58         header( "Content-type: text/html; charset=$wgOutputEncoding" );
  59         if($msg == "") $msg = wfMsgNoDB( "noconnect" );
  60         $text = $msg;
  61
  62         if($wgUseFileCache) {
  63                 if($wgTitle) {
  64                         $t =& $wgTitle;
  65                 } else {
  66                         if($title) {
  67                                 $t = Title::newFromURL( $title );
  68                         } else {
  69                                 $t = Title::newFromText( wfMsgNoDB( "mainpage" ) );
  70                         }
  71                 }
  72
  73                 $cache = new CacheManager( $t );
  74                 if( $cache->isFileCached() ) {
  75                         $msg = "<p style='color: red'><b>$msg<br>\n" .
  76                                 wfMsgNoDB( "cachederror" ) . "</b></p>\n";
  77
  78                         $tag = "<div id='article'>";
  79                         $text = str_replace(
  80                                 $tag,
  81                                 $tag . $msg,
  82                                 $cache->fetchPageText() );
  83                 }
  84         }
  85
  86         /* Don't cache error pages!  They cause no end of trouble... */
  87         header( "Cache-control: none" );
  88         header( "Pragma: nocache" );
  89         echo $text;
  90         exit;
  91 }
  92
  93 # $db: DB_READ  = -1    read from slave (or only server)
  94 #      DB_WRITE = -2    write to master (or only server)
  95 #      0,1,2,...        query a database with a specific index
  96 # Replication is not actually implemented just yet
  97 function wfQuery( $sql, $db, $fname = "" )
  98 {
  99         global $wgLastDatabaseQuery, $wgOut, $wgDebugDumpSql, $wgBufferSQLResults;
 100         global $wgProfiling;
 101         if ( $wgProfiling ) {
 102                 # wfGeneralizeSQL will probably cut down the query to reasonable
 103                 # logging size most of the time. The substr is really just a sanity check.
 104                 $profName = "wfQuery: " . substr( wfGeneralizeSQL( $sql ), 0, 255 );
 105
 106                 wfProfileIn( $profName );
 107         }
 108
 109         if ( !is_numeric( $db ) ) {
 110                 # Someone has tried to call this the old way
 111                 $wgOut->fatalError( wfMsgNoDB( "wrong_wfQuery_params", $db, $sql ) );
 112         }
 113
 114         $wgLastDatabaseQuery = $sql;
 115
 116         if( $wgDebugDumpSql ) {
 117                 $sqlx = substr( $sql, 0, 500 );
 118                 $sqlx = wordwrap(strtr($sqlx,"\t\n","  "));
 119                 wfDebug( "SQL: $sqlx\n" );
 120         }
 121
 122         $conn = wfGetDB();
 123         if( $wgBufferSQLResults ) {
 124                 $ret = mysql_query( $sql, $conn );
 125         } else {
 126                 $ret = mysql_unbuffered_query( $sql, $conn );
 127         }
 128
 129         if ( false === $ret ) {
 130                 $wgOut->databaseError( $fname );
 131                 exit;
 132         }
 133
 134         if ( $wgProfiling ) {
 135                 wfProfileOut( $profName );
 136         }
 137         return $ret;
 138 }
 139
 140 function wfUnbufferedQuery( $sql, $db, $fname = "" ){
 141         global $wgBufferSQLResults;
 142         $oldstate = $wgBufferSQLResults;
 143
 144         $wgBufferSQLResults = true;
 145         $res = wfQuery($sql, $db, $fname);
 146
 147         $wgBufferSQLResults = $oldstate;
 148         return $res;
 149 }
 150
 151 function wfFreeResult( $res ) { mysql_free_result( $res ); }
 152 function wfFetchObject( $res ) { return mysql_fetch_object( $res ); }
 153 function wfNumRows( $res ) { return mysql_num_rows( $res ); }
 154 function wfNumFields( $res ) { return mysql_num_fields( $res ); }
 155 function wfFieldName( $res, $n ) { return mysql_field_name( $res, $n ); }
 156 function wfInsertId() { return mysql_insert_id( wfGetDB() ); }
 157 function wfDataSeek( $res, $row ) { return mysql_data_seek( $res, $row ); }
 158 function wfLastErrno() { return mysql_errno(); }
 159 function wfLastError() { return mysql_error(); }
 160 function wfAffectedRows() { return mysql_affected_rows( wfGetDB() ); }
 161
 162 function wfLastDBquery()
 163 {
 164         global $wgLastDatabaseQuery;
 165         return $wgLastDatabaseQuery;
 166 }
 167
 168 function wfSetSQL( $table, $var, $value, $cond )
 169 {
 170         $sql = "UPDATE $table SET $var = '" .
 171           wfStrencode( $value ) . "' WHERE ($cond)";
 172         wfQuery( $sql, DB_WRITE, "wfSetSQL" );
 173 }
 174
 175 function wfGetSQL( $table, $var, $cond )
 176 {
 177         $sql = "SELECT $var FROM $table WHERE ($cond)";
 178         $result = wfQuery( $sql, DB_READ, "wfGetSQL" );
 179
 180         $ret = "";
 181         if ( mysql_num_rows( $result ) > 0 ) {
 182                 $s = mysql_fetch_object( $result );
 183                 $ret = $s->$var;
 184                 mysql_free_result( $result );
 185         }
 186         return $ret;
 187 }
 188
 189 function wfStrencode( $s )
 190 {
 191         return addslashes( $s );
 192 }
 193
 194 # Ideally we'd be using actual time fields in the db
 195 function wfTimestamp2Unix( $ts ) {
 196         return gmmktime( ( (int)substr( $ts, 8, 2) ),
 197                   (int)substr( $ts, 10, 2 ), (int)substr( $ts, 12, 2 ),
 198                   (int)substr( $ts, 4, 2 ), (int)substr( $ts, 6, 2 ),
 199                   (int)substr( $ts, 0, 4 ) );
 200 }
 201
 202 function wfUnix2Timestamp( $unixtime ) {
 203         return gmdate( "YmdHis", $unixtime );
 204 }
 205
 206 function wfTimestampNow() {
 207         # return NOW
 208         return gmdate( "YmdHis" );
 209 }
 210
 211 # Sorting hack for MySQL 3, which doesn't use index sorts for DESC
 212 function wfInvertTimestamp( $ts ) {
 213         return strtr(
 214                 $ts,
 215                 "0123456789",
 216                 "9876543210"
 217         );
 218 }
 219
 220 # Removes most variables from an SQL query and replaces them with X or N for numbers.
 221 # It's only slightly flawed. Don't use for anything important.
 222 function wfGeneralizeSQL( $sql )
 223 {
 224         # This could be done faster with some arrays and a single preg_replace,
 225         # but this show more clearly what's going on. Which may be a good thing.
 226         $sql = preg_replace( "/'.*?[^\\\\]'/", "'X'", $sql );
 227         $sql = preg_replace ( "/-?\d+/" , "N", $sql);
 228         $sql = preg_replace ( "/\s+/", " ", $sql);
 229         return $sql;
 230 }
 231
 232 function wfFieldExists( $table, $field )
 233 {
 234         $fname = "wfFieldExists";
 235         $res = wfQuery( "DESCRIBE $table", DB_READ, $fname );
 236         $found = false;
 237
 238         while ( $row = wfFetchObject( $res ) ) {
 239                 if ( $row->Field == $field ) {
 240                         $found = true;
 241                         break;
 242                 }
 243         }
 244         return $found;
 245 }
 246
 247 function wfIndexExists( $table, $index )
 248 {
 249         global $wgDBname;
 250         $fname = "wfIndexExists";
 251         $sql = "SHOW INDEXES FROM $table";
 252         $res = wfQuery( $sql, DB_READ, $fname );
 253         $found = false;
 254         while ( $row = wfFetchObject( $res ) ) {
 255                 if ( $row->Key_name == $index ) {
 256                         $found = true;
 257                         break;
 258                 }
 259         }
 260         return $found;
 261 }
 262 ?>