From 414fca2323456c0f59d0a155784f9dcac393a227 Mon Sep 17 00:00:00 2001
From: Aryeh Gregor <simetrical@users.mediawiki.org>
Date: Thu, 25 Jan 2007 03:07:39 +0000
Subject: [PATCH] (bug 8652) Catch exceptions generated by malformed XML in
 multipage media.  Note: not tested, since I don't have all that fancy
 image-using stuff set up (:P), but it's just a try/catch block, so at worst
 it just won't work.  Better than having the entire page crash due to an
 unhandled exception . . .

Incidentally, should we maybe use set_exception_handler()?
---
 RELEASE-NOTES                     |  1 +
 includes/ImagePage.php            | 76 ++++++++++++++++++-------------
 languages/messages/MessagesEn.php |  1 +
 3 files changed, 47 insertions(+), 31 deletions(-)

diff --git a/RELEASE-NOTES b/RELEASE-NOTES
index 1024128f9e..075873f6c6 100644
--- a/RELEASE-NOTES
+++ b/RELEASE-NOTES
@@ -146,6 +146,7 @@ lighter making things easier to read.
   alias to that which should be used to make it more self documentating.
 * (bug 8749) Bring MySQL 5 table defs back into sync
 * (bug 8751) Set session cookies to HTTPS-only to match other cookies
+* (bug 8652) Catch exceptions generated by malformed XML in multipage media
 
 
 == Languages updated ==
diff --git a/includes/ImagePage.php b/includes/ImagePage.php
index 2e6e94e4d3..f57e9d754a 100644
--- a/includes/ImagePage.php
+++ b/includes/ImagePage.php
@@ -248,39 +248,53 @@ class ImagePage extends Article {
 				     htmlspecialchars( $this->img->getTitle()->getPrefixedText() ).'" />' . $anchorclose . '</div>' );
 
 				if ( $this->img->isMultipage() ) {
-					$count = $this->img->pageCount();
+					try {
+						// Apparently SimpleXmlElement->__construct() can throw
+						// exceptions for malformed XML, although this isn't documented . . .
+						// http://us2.php.net/manual/en/function.simplexml-element-construct.php
 
-					if ( $page > 1 ) {
-						$label = $wgOut->parse( wfMsg( 'imgmultipageprev' ), false );
-						$link = $sk->makeLinkObj( $this->mTitle, $label, 'page='. ($page-1) );
-						$this->img->selectPage( $page - 1 );
-						$thumb1 = $sk->makeThumbLinkObj( $this->img, $link, $label, 'none' );
-					} else {
-						$thumb1 = '';
-					}
-
-					if ( $page < $count ) {
-						$label = wfMsg( 'imgmultipagenext' );
-						$this->img->selectPage( $page + 1 );
-						$link = $sk->makeLinkObj( $this->mTitle, $label, 'page='. ($page+1) );
-						$thumb2 = $sk->makeThumbLinkObj( $this->img, $link, $label, 'none' );
-					} else {
-						$thumb2 = '';
-					}
-
-					$select = '<form name="pageselector" action="' . $this->img->getEscapeLocalUrl( '' ) . '" method="GET" onchange="document.pageselector.submit();">' ;
-					$select .= $wgOut->parse( wfMsg( 'imgmultigotopre' ), false ) .
-						' <select id="pageselector" name="page">';
-					for ( $i=1; $i <= $count; $i++ ) {
-						$select .= Xml::option( $wgLang->formatNum( $i ), $i,
-							$i == $page );
+						$count = $this->img->pageCount();
+	
+						if ( $page > 1 ) {
+							$label = $wgOut->parse( wfMsg( 'imgmultipageprev' ), false );
+							$link = $sk->makeLinkObj( $this->mTitle, $label, 'page='. ($page-1) );
+							$this->img->selectPage( $page - 1 );
+							$thumb1 = $sk->makeThumbLinkObj( $this->img, $link, $label, 'none' );
+						} else {
+							$thumb1 = '';
+						}
+	
+						if ( $page < $count ) {
+							$label = wfMsg( 'imgmultipagenext' );
+							$this->img->selectPage( $page + 1 );
+							$link = $sk->makeLinkObj( $this->mTitle, $label, 'page='. ($page+1) );
+							$thumb2 = $sk->makeThumbLinkObj( $this->img, $link, $label, 'none' );
+						} else {
+							$thumb2 = '';
+						}
+	
+						$select = '<form name="pageselector" action="' . $this->img->getEscapeLocalUrl( '' ) . '" method="GET" onchange="document.pageselector.submit();">' ;
+						$select .= $wgOut->parse( wfMsg( 'imgmultigotopre' ), false ) .
+							' <select id="pageselector" name="page">';
+						for ( $i=1; $i <= $count; $i++ ) {
+							$select .= Xml::option( $wgLang->formatNum( $i ), $i,
+								$i == $page );
+						}
+						$select .= '</select>' . $wgOut->parse( wfMsg( 'imgmultigotopost' ), false ) .
+							'<input type="submit" value="' .
+							htmlspecialchars( wfMsg( 'imgmultigo' ) ) . '"></form>';
+	
+						$wgOut->addHTML( '</td><td><div class="multipageimagenavbox">' .
+						   "$select<hr />$thumb1\n$thumb2<br clear=\"all\" /></div></td></tr></table>" );
+					} catch( Exception $e ) {
+						if ( $e->getText() == "String could not be parsed as XML" ) {
+							// Hacky and fragile string test, yay
+							$errorMsg = wfMsg( 'imgmultiparseerror' );
+							$wgOut->addHtml( "</td><td>$errorMsg</td></tr></table>" );
+						} else {
+							throw $e;
+						}
 					}
-					$select .= '</select>' . $wgOut->parse( wfMsg( 'imgmultigotopost' ), false ) .
-						'<input type="submit" value="' .
-						htmlspecialchars( wfMsg( 'imgmultigo' ) ) . '"></form>';
-
-					$wgOut->addHTML( '</td><td><div class="multipageimagenavbox">' .
-					   "$select<hr />$thumb1\n$thumb2<br clear=\"all\" /></div></td></tr></table>" );
 				}
 			} else {
 				#if direct link is allowed but it's not a renderable image, show an icon.
diff --git a/languages/messages/MessagesEn.php b/languages/messages/MessagesEn.php
index 96dead006e..45e759f03d 100644
--- a/languages/messages/MessagesEn.php
+++ b/languages/messages/MessagesEn.php
@@ -2722,6 +2722,7 @@ Please confirm that really want to recreate this page.',
 'imgmultigo' => 'Go!',
 'imgmultigotopre' => 'Go to page',
 'imgmultigotopost' => '',
+'imgmultiparseerror' => 'The image file appears to be corrupted or incorrect, so {{SITENAME}} cannot retrieve a list of pages.',
 
 # Table pager
 'ascending_abbrev' => 'asc',
-- 
2.20.1