Add an install/update-time test for the PHP+libxml2 horrible XML input corruption...

diff --git a/install-utils.inc b/install-utils.inc
index 473cdf5..d8f73ce 100644 (file)
--- a/install-utils.inc
+++ b/install-utils.inc
@@ -33,6 +33,16 @@ function install_version_checks() {
                        "or higher. ABORTING. (http://bugs.php.net/bug.php?id=34879 for details)\n";
                die( -1 );
        }
+       
+       $test = new PhpXmlBugTester();
+       if( !$test->ok ) {
+               echo "Your system has a combination of PHP and libxml2 versions which is buggy\n" .
+                       "and can cause hidden data corruption in MediaWiki and other web apps.\n" .
+                       "Upgrade to PHP 5.2.9 or later and libxml2 2.7.2 or later!\n" .
+                       "ABORTING (http://bugs.php.net/bug.php?id=45996 for details).\n";
+               die( -1 );
+       }
+       
 
        global $wgCommandLineMode;
        $wgCommandLineMode = true;
@@ -40,6 +50,28 @@ function install_version_checks() {
        @set_time_limit( 0 );
 }
 
+/**
+ * Test for PHP+libxml2 bug which breaks XML input subtly with certain versions.
+ * http://bugs.php.net/bug.php?id=45996
+ * Known fixed with PHP 5.2.9 + libxml2-2.7.3
+ */
+class PhpXmlBugTester {
+       var $parsedData = '';
+       var $ok = false;
+       function __construct() {
+               $charData = '<b>c</b>';
+               $xml = '<a>' . htmlspecialchars( $charData ) . '</a>';
+               
+               $parser = xml_parser_create();
+               xml_set_character_data_handler( $parser, array( $this, 'chardata' ) );
+               $parsedOk = xml_parse($parser, $xml, true);
+               $this->ok = $parsedOk && ($this->parsedData == $charData);
+       }
+       function chardata($parser, $data) {
+               $this->parsedData .= $data;
+       }
+}
+
 function readconsole( $prompt = '' ) {
        static $isatty = null;
        if ( is_null( $isatty ) ) {