includes/Exception.php

   1 <?php
   2
   3 /**
   4  * MediaWiki exception
   5  * @addtogroup Exception
   6  */
   7 class MWException extends Exception
   8 {
   9         function useOutputPage() {
  10                 return !empty( $GLOBALS['wgFullyInitialised'] ) &&
  11                         !empty( $GLOBALS['wgArticle'] ) && !empty( $GLOBALS['wgTitle'] );
  12         }
  13
  14         function useMessageCache() {
  15                 global $wgLang;
  16                 return is_object( $wgLang );
  17         }
  18
  19         /** Get a message from i18n */
  20         function msg( $key, $fallback /*[, params...] */ ) {
  21                 $args = array_slice( func_get_args(), 2 );
  22                 if ( $this->useMessageCache() ) {
  23                         return wfMsgReal( $key, $args );
  24                 } else {
  25                         return wfMsgReplaceArgs( $fallback, $args );
  26                 }
  27         }
  28
  29         /* If wgShowExceptionDetails, return a HTML message with a backtrace to the error. */
  30         function getHTML() {
  31                 global $wgShowExceptionDetails;
  32                 if( $wgShowExceptionDetails ) {
  33                         return '<p>' . htmlspecialchars( $this->getMessage() ) .
  34                                 '</p><p>Backtrace:</p><p>' . nl2br( htmlspecialchars( $this->getTraceAsString() ) ) .
  35                                 "</p>\n";
  36                 } else {
  37                         return "<p>Set <b><tt>\$wgShowExceptionDetails = true;</tt></b> " .
  38                                 "in LocalSettings.php to show detailed debugging information.</p>";
  39                 }
  40         }
  41
  42         /* If wgShowExceptionDetails, return a text message with a backtrace to the error */
  43         function getText() {
  44                 global $wgShowExceptionDetails;
  45                 if( $wgShowExceptionDetails ) {
  46                         return $this->getMessage() .
  47                                 "\nBacktrace:\n" . $this->getTraceAsString() . "\n";
  48                 } else {
  49                         return "<p>Set <tt>\$wgShowExceptionDetails = true;</tt> " .
  50                                 "in LocalSettings.php to show detailed debugging information.</p>";
  51                 }
  52         }
  53
  54         /* Return titles of this error page */
  55         function getPageTitle() {
  56                 if ( $this->useMessageCache() ) {
  57                         return wfMsg( 'internalerror' );
  58                 } else {
  59                         global $wgSitename;
  60                         return "$wgSitename error";
  61                 }
  62         }
  63
  64         /** Return the requested URL and point to file and line number from which the
  65          * exception occured
  66          */
  67         function getLogMessage() {
  68                 global $wgRequest;
  69                 $file = $this->getFile();
  70                 $line = $this->getLine();
  71                 $message = $this->getMessage();
  72                 return $wgRequest->getRequestURL() . " Exception from line $line of $file: $message";
  73         }
  74
  75         /** Output the exception report using HTML */
  76         function reportHTML() {
  77                 global $wgOut;
  78                 if ( $this->useOutputPage() ) {
  79                         $wgOut->setPageTitle( $this->getPageTitle() );
  80                         $wgOut->setRobotpolicy( "noindex,nofollow" );
  81                         $wgOut->setArticleRelated( false );
  82                         $wgOut->enableClientCache( false );
  83                         $wgOut->redirect( '' );
  84                         $wgOut->clearHTML();
  85                         $wgOut->addHTML( $this->getHTML() );
  86                         $wgOut->output();
  87                 } else {
  88                         echo $this->htmlHeader();
  89                         echo $this->getHTML();
  90                         echo $this->htmlFooter();
  91                 }
  92         }
  93
  94         /** Print the exception report using text */
  95         function reportText() {
  96                 echo $this->getText();
  97         }
  98
  99         /* Output a report about the exception and takes care of formatting.
 100          * It will be either HTML or plain text based on $wgCommandLineMode.
 101          */
 102         function report() {
 103                 global $wgCommandLineMode;
 104                 if ( $wgCommandLineMode ) {
 105                         $this->reportText();
 106                 } else {
 107                         $log = $this->getLogMessage();
 108                         if ( $log ) {
 109                                 wfDebugLog( 'exception', $log );
 110                         }
 111                         $this->reportHTML();
 112                 }
 113         }
 114
 115         function htmlHeader() {
 116                 global $wgLogo, $wgSitename, $wgOutputEncoding;
 117
 118                 if ( !headers_sent() ) {
 119                         header( 'HTTP/1.0 500 Internal Server Error' );
 120                         header( 'Content-type: text/html; charset='.$wgOutputEncoding );
 121                         /* Don't cache error pages!  They cause no end of trouble... */
 122                         header( 'Cache-control: none' );
 123                         header( 'Pragma: nocache' );
 124                 }
 125                 $title = $this->getPageTitle();
 126                 echo "<html>
 127                 <head>
 128                 <title>$title</title>
 129                 </head>
 130                 <body>
 131                 <h1><img src='$wgLogo' style='float:left;margin-right:1em' alt=''>$title</h1>
 132                 ";
 133         }
 134
 135         function htmlFooter() {
 136                 echo "</body></html>";
 137         }
 138
 139 }
 140
 141 /**
 142  * Exception class which takes an HTML error message, and does not
 143  * produce a backtrace. Replacement for OutputPage::fatalError().
 144  * @addtogroup Exception
 145  */
 146 class FatalError extends MWException {
 147         function getHTML() {
 148                 return $this->getMessage();
 149         }
 150
 151         function getText() {
 152                 return $this->getMessage();
 153         }
 154 }
 155
 156 /**
 157  * @addtogroup Exception
 158  */
 159 class ErrorPageError extends MWException {
 160         public $title, $msg;
 161
 162         /**
 163          * Note: these arguments are keys into wfMsg(), not text!
 164          */
 165         function __construct( $title, $msg ) {
 166                 $this->title = $title;
 167                 $this->msg = $msg;
 168                 parent::__construct( wfMsg( $msg ) );
 169         }
 170
 171         function report() {
 172                 global $wgOut;
 173                 $wgOut->showErrorPage( $this->title, $this->msg );
 174                 $wgOut->output();
 175         }
 176 }
 177
 178 /**
 179  * Install an exception handler for MediaWiki exception types.
 180  */
 181 function wfInstallExceptionHandler() {
 182         set_exception_handler( 'wfExceptionHandler' );
 183 }
 184
 185 /**
 186  * Report an exception to the user
 187  */
 188 function wfReportException( Exception $e ) {
 189          if ( $e instanceof MWException ) {
 190                  try {
 191                          $e->report();
 192                  } catch ( Exception $e2 ) {
 193                          // Exception occurred from within exception handler
 194                          // Show a simpler error message for the original exception,
 195                          // don't try to invoke report()
 196                          $message = "MediaWiki internal error.\n\n" .
 197                          "Original exception: " . $e->__toString() .
 198                          "\n\nException caught inside exception handler: " .
 199                          $e2->__toString() . "\n";
 200
 201                          if ( !empty( $GLOBALS['wgCommandLineMode'] ) ) {
 202                                  echo $message;
 203                          } else {
 204                                  echo nl2br( htmlspecialchars( $message ) ). "\n";
 205                          }
 206                  }
 207          } else {
 208                  echo $e->__toString();
 209          }
 210 }
 211
 212 /**
 213  * Exception handler which simulates the appropriate catch() handling:
 214  *
 215  *   try {
 216  *       ...
 217  *   } catch ( MWException $e ) {
 218  *       $e->report();
 219  *   } catch ( Exception $e ) {
 220  *       echo $e->__toString();
 221  *   }
 222  */
 223 function wfExceptionHandler( $e ) {
 224         global $wgFullyInitialised;
 225         wfReportException( $e );
 226
 227         // Final cleanup, similar to wfErrorExit()
 228         if ( $wgFullyInitialised ) {
 229                 try {
 230                         wfLogProfilingData(); // uses $wgRequest, hence the $wgFullyInitialised condition
 231                 } catch ( Exception $e ) {}
 232         }
 233
 234         // Exit value should be nonzero for the benefit of shell jobs
 235         exit( 1 );
 236 }
 237
 238 ?>