1 files changed, 64 insertions, 0 deletions
diff --git a/includes/OutputHandler.php b/includes/OutputHandler.php
new file mode 100644
index 00000000..d7e7c90f
--- /dev/null
+++ b/includes/OutputHandler.php
@@ -0,0 +1,64 @@
+<?php
+
+/**
+ * Standard output handler for use with ob_start
+ */
+function wfOutputHandler( $s ) {
+	global $wgDisableOutputCompression;
+	$s = wfMangleFlashPolicy( $s );
+	if ( !$wgDisableOutputCompression && !ini_get( 'zlib.output_compression' ) ) {
+		if ( !defined( 'MW_NO_OUTPUT_COMPRESSION' ) ) {
+			$s = wfGzipHandler( $s );
+		}
+		if ( !ini_get( 'output_handler' ) ) {
+			wfDoContentLength( strlen( $s ) );
+		}
+	}
+	return $s;
+}
+
+/**
+ * Handler that compresses data with gzip if allowed by the Accept header.
+ * Unlike ob_gzhandler, it works for HEAD requests too.
+ */
+function wfGzipHandler( $s ) {
+	if ( function_exists( 'gzencode' ) && !headers_sent() ) {
+		$tokens = preg_split( '/[,; ]/', $_SERVER['HTTP_ACCEPT_ENCODING'] );
+		if ( in_array( 'gzip', $tokens ) ) {
+			header( 'Content-Encoding: gzip' );
+			$s = gzencode( $s, 3 );
+
+			# Set vary header if it hasn't been set already
+			$headers = headers_list();
+			$foundVary = false;
+			foreach ( $headers as $header ) {
+				if ( substr( $header, 0, 5 ) == 'Vary:' ) {
+					$foundVary = true;
+					break;
+				}
+			}
+			if ( !$foundVary ) {
+				header( 'Vary: Accept-Encoding' );
+			}
+		}
+	}
+	return $s;
+}
+
+/**
+ * Mangle flash policy tags which open up the site to XSS attacks.
+ */
+function wfMangleFlashPolicy( $s ) {
+	return preg_replace( '/\<\s*cross-domain-policy\s*\>/i', '<NOT-cross-domain-policy>', $s );
+}
+
+/**
+ * Add a Content-Length header if possible. This makes it cooperate with squid better.
+ */
+function wfDoContentLength( $length ) {
+	if ( !headers_sent() && $_SERVER['SERVER_PROTOCOL'] == 'HTTP/1.0' ) {
+		header( "Content-Length: $length" );
+	}
+}
+
+?>