MDL-10092:

Decode HTML entities before processing.

Merged from STABLE_18

filter/tex/latex.php

@@ -1,4 +1,4 @@
-<?php
+<?php // $Id$
     // latex.php
     // render TeX stuff using latex - this will not work on all platforms
     // or configurations. Only works on Linux and Mac with appropriate 

filter/tex/pix.php

@@ -56,7 +56,8 @@
             $latex = new latex();
             $density = $CFG->filter_tex_density;
             $background = $CFG->filter_tex_latexbackground;
-            $latex_path = $latex->render( $texcache->rawtext, $md5, 12, $density, $background );
+            $texexp = html_entity_decode( $texcache->rawtext );
+            $latex_path = $latex->render( $texexp, $md5, 12, $density, $background );
             if ($latex_path) {    
                 copy( $latex_path, $pathname );
                 $latex->clean_up( $md5 );

filter/tex/texdebug.php

@@ -254,6 +254,8 @@
         $gif = "$latex->temp_dir/$md5.gif";
 
         // put the expression as a file into the temp area
+        $expression = html_entity_decode( $expression );
+        $output .= "<p>Processing TeX expression:</p><pre>$expression</pre>\n";
         $doc = $latex->construct_latex_document( $expression );
         $fh = fopen( $tex, 'w' );
         fputs( $fh, $doc );