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_pconnect( $wgDBserver, $wgDBuser, $wgDBpassword )
  37                         or wfEmergencyAbort();
  38
  39                 if( !mysql_select_db( $wgDBname, $wgDBconnection ) ) {
  40                         /* Persistent connections may become stuck in an unusable state */
  41                         wfDebug( "Persistent connection is broken?\n", true );
  42
  43                         @$wgDBconnection = mysql_connect( $wgDBserver, $wgDBuser, $wgDBpassword )
  44                                 or wfEmergencyAbort();
  45
  46                         @mysql_select_db( $wgDBname, $wgDBconnection )
  47                                 or wfEmergencyAbort();
  48                 }
  49         }
  50         # mysql_ping( $wgDBconnection );
  51         return $wgDBconnection;
  52 }
  53
  54 /* Call this function if we couldn't contact the database...
  55    We'll try to use the cache to display something in the meantime */
  56 function wfEmergencyAbort( $msg = "" ) {
  57         global $wgTitle, $wgUseFileCache, $title, $wgOutputEncoding;
  58
  59         header( "Content-type: text/html; charset=$wgOutputEncoding" );
  60         if($msg == "") $msg = wfMsgNoDB( "noconnect" );
  61         $text = $msg;
  62
  63         if($wgUseFileCache) {
  64                 if($wgTitle) {
  65                         $t =& $wgTitle;
  66                 } else {
  67                         if($title) {
  68                                 $t = Title::newFromURL( $title );
  69                         } else {
  70                                 $t = Title::newFromText( wfMsgNoDB( "mainpage" ) );
  71                         }
  72                 }
  73
  74                 $cache = new CacheManager( $t );
  75                 if( $cache->isFileCached() ) {
  76                         $msg = "<p style='color: red'><b>$msg<br>\n" .
  77                                 wfMsgNoDB( "cachederror" ) . "</b></p>\n";
  78
  79                         $tag = "<div id='article'>";
  80                         $text = str_replace(
  81                                 $tag,
  82                                 $tag . $msg,
  83                                 $cache->fetchPageText() );
  84                 }
  85         }
  86
  87         /* Don't cache error pages!  They cause no end of trouble... */
  88         header( "Cache-control: none" );
  89         header( "Pragma: nocache" );
  90         echo $text;
  91         wfAbruptExit();
  92 }
  93
  94 # $db: DB_READ  = -1    read from slave (or only server)
  95 #      DB_WRITE = -2    write to master (or only server)
  96 #      0,1,2,...        query a database with a specific index
  97 # Replication is not actually implemented just yet
  98 function wfQuery( $sql, $db, $fname = "" )
  99 {
 100         global $wgLastDatabaseQuery, $wgOut, $wgDebugDumpSql, $wgBufferSQLResults,
 101                 $wgIgnoreSQLErrors, $wgProfiling;
 102
 103         if ( $wgProfiling ) {
 104                 # wfGeneralizeSQL will probably cut down the query to reasonable
 105                 # logging size most of the time. The substr is really just a sanity check.
 106                 $profName = "wfQuery: " . substr( wfGeneralizeSQL( $sql ), 0, 255 );
 107                 wfProfileIn( $profName );
 108         }
 109
 110         if ( !is_numeric( $db ) ) {
 111                 # Someone has tried to call this the old way
 112                 $wgOut->fatalError( wfMsgNoDB( "wrong_wfQuery_params", $db, $sql ) );
 113         }
 114
 115         $wgLastDatabaseQuery = $sql;
 116
 117         if( $wgDebugDumpSql ) {
 118                 $sqlx = substr( $sql, 0, 500 );
 119                 $sqlx = wordwrap(strtr($sqlx,"\t\n","  "));
 120                 wfDebug( "SQL: $sqlx\n" );
 121         }
 122
 123         $conn = wfGetDB();
 124         if( $wgBufferSQLResults ) {
 125                 $ret = mysql_query( $sql, $conn );
 126         } else {
 127                 $ret = mysql_unbuffered_query( $sql, $conn );
 128         }
 129
 130         if ( false === $ret ) {
 131                 if( $wgIgnoreSQLErrors ) {
 132                         wfDebug("SQL ERROR (ignored): " . mysql_error( $conn ) . "\n");
 133                 } else {
 134                         wfDebug("SQL ERROR: " . mysql_error( $conn ) . "\n");
 135                         $wgOut->databaseError( $fname ); // calls wfAbruptExit()
 136                 }
 137         }
 138
 139         if ( $wgProfiling ) {
 140                 wfProfileOut( $profName );
 141         }
 142         return $ret;
 143 }
 144
 145 # Turns buffering of SQL result sets on (true) or off (false). Default is
 146 # "on" and it should not be changed without good reasons.
 147 # Returns the previous state.
 148
 149 function wfBufferSQLResults( $newstate ){
 150         global $wgBufferSQLResults;
 151         $oldstate = $wgBufferSQLResults;
 152         $wgBufferSQLResults = $newstate;
 153         return $oldstate;
 154 }
 155
 156 # Turns on (false) or off (true) the automatic generation and sending
 157 # of a "we're sorry, but there has been a database error" page on
 158 # database errors. Default is on (false). When turned off, the
 159 # code should use wfLastErrno() and wfLastError() to handle the
 160 # situation as appropriate.
 161 # Returns the previous state.
 162
 163 function wfIgnoreSQLErrors( $newstate ){
 164         global $wgIgnoreSQLErrors;
 165         $oldstate = $wgIgnoreSQLErrors;
 166         $wgIgnoreSQLErrors = $newstate;
 167         return $oldstate;
 168 }
 169
 170 function wfFreeResult( $res ) { mysql_free_result( $res ); }
 171 function wfFetchObject( $res ) { return mysql_fetch_object( $res ); }
 172 function wfNumRows( $res ) { return mysql_num_rows( $res ); }
 173 function wfNumFields( $res ) { return mysql_num_fields( $res ); }
 174 function wfFieldName( $res, $n ) { return mysql_field_name( $res, $n ); }
 175 function wfInsertId() { return mysql_insert_id( wfGetDB() ); }
 176 function wfDataSeek( $res, $row ) { return mysql_data_seek( $res, $row ); }
 177 function wfLastErrno() { return mysql_errno(); }
 178 function wfLastError() { return mysql_error(); }
 179 function wfAffectedRows() { return mysql_affected_rows( wfGetDB() ); }
 180
 181 function wfLastDBquery()
 182 {
 183         global $wgLastDatabaseQuery;
 184         return $wgLastDatabaseQuery;
 185 }
 186
 187 function wfSetSQL( $table, $var, $value, $cond )
 188 {
 189         $sql = "UPDATE $table SET $var = '" .
 190           wfStrencode( $value ) . "' WHERE ($cond)";
 191         wfQuery( $sql, DB_WRITE, "wfSetSQL" );
 192 }
 193
 194 function wfGetSQL( $table, $var, $cond )
 195 {
 196         $sql = "SELECT $var FROM $table WHERE ($cond)";
 197         $result = wfQuery( $sql, DB_READ, "wfGetSQL" );
 198
 199         $ret = "";
 200         if ( mysql_num_rows( $result ) > 0 ) {
 201                 $s = mysql_fetch_object( $result );
 202                 $ret = $s->$var;
 203                 mysql_free_result( $result );
 204         }
 205         return $ret;
 206 }
 207
 208 function wfStrencode( $s )
 209 {
 210         return addslashes( $s );
 211 }
 212
 213 # Ideally we'd be using actual time fields in the db
 214 function wfTimestamp2Unix( $ts ) {
 215         return gmmktime( ( (int)substr( $ts, 8, 2) ),
 216                   (int)substr( $ts, 10, 2 ), (int)substr( $ts, 12, 2 ),
 217                   (int)substr( $ts, 4, 2 ), (int)substr( $ts, 6, 2 ),
 218                   (int)substr( $ts, 0, 4 ) );
 219 }
 220
 221 function wfUnix2Timestamp( $unixtime ) {
 222         return gmdate( "YmdHis", $unixtime );
 223 }
 224
 225 function wfTimestampNow() {
 226         # return NOW
 227         return gmdate( "YmdHis" );
 228 }
 229
 230 # Sorting hack for MySQL 3, which doesn't use index sorts for DESC
 231 function wfInvertTimestamp( $ts ) {
 232         return strtr(
 233                 $ts,
 234                 "0123456789",
 235                 "9876543210"
 236         );
 237 }
 238
 239 # Removes most variables from an SQL query and replaces them with X or N for numbers.
 240 # It's only slightly flawed. Don't use for anything important.
 241 function wfGeneralizeSQL( $sql )
 242 {
 243         # This does the same as the regexp below would do, but in such a way
 244         # as to avoid crashing php on some large strings.
 245         # $sql = preg_replace ( "/'([^\\\\']|\\\\.)*'|\"([^\\\\\"]|\\\\.)*\"/", "'X'", $sql);
 246
 247         $sql = str_replace ( "\\\\", "", $sql);
 248         $sql = str_replace ( "\\'", "", $sql);
 249         $sql = str_replace ( "\\\"", "", $sql);
 250         $sql = preg_replace ("/'.*'/s", "'X'", $sql);
 251         $sql = preg_replace ('/".*"/s', "'X'", $sql);
 252
 253         # All newlines, tabs, etc replaced by single space
 254         $sql = preg_replace ( "/\s+/", " ", $sql);
 255
 256         # All numbers => N
 257         $sql = preg_replace ('/-?[0-9]+/s', "N", $sql);
 258
 259         return $sql;
 260 }
 261
 262 function wfFieldExists( $table, $field )
 263 {
 264         $fname = "wfFieldExists";
 265         $res = wfQuery( "DESCRIBE $table", DB_READ, $fname );
 266         $found = false;
 267
 268         while ( $row = wfFetchObject( $res ) ) {
 269                 if ( $row->Field == $field ) {
 270                         $found = true;
 271                         break;
 272                 }
 273         }
 274         return $found;
 275 }
 276
 277 function wfIndexExists( $table, $index )
 278 {
 279         global $wgDBname;
 280         $fname = "wfIndexExists";
 281         $sql = "SHOW INDEXES FROM $table";
 282         $res = wfQuery( $sql, DB_READ, $fname );
 283         $found = false;
 284         while ( $row = wfFetchObject( $res ) ) {
 285                 if ( $row->Key_name == $index ) {
 286                         $found = true;
 287                         break;
 288                 }
 289         }
 290         return $found;
 291 }
 292 ?>