From c2f3786d90788b2de74f615bae06a161e4ee7237 Mon Sep 17 00:00:00 2001
From: CaMer0n <cameron@e107coders.org>
Date: Fri, 3 Sep 2010 22:02:30 +0000
Subject: [PATCH] eTag validation fix and If-None-Match support.

---
 e107_themes/templates/footer_default.php | 29 ++++++++++++++++++++++--
 1 file changed, 27 insertions(+), 2 deletions(-)

diff --git a/e107_themes/templates/footer_default.php b/e107_themes/templates/footer_default.php
index 1460fec19..e3bf1bc32 100644
--- a/e107_themes/templates/footer_default.php
+++ b/e107_themes/templates/footer_default.php
@@ -289,8 +289,23 @@ echo "</body></html>";
 $page = ob_get_clean();
 
 $etag = md5($page);
-header("Cache-Control: must-revalidate");
-header("ETag: \"{$etag}\"");
+
+
+if (isset($_SERVER['HTTP_IF_NONE_MATCH']))
+{
+	$IF_NONE_MATCH = str_replace('"','',$_SERVER['HTTP_IF_NONE_MATCH']);
+	
+	if($IF_NONE_MATCH == $etag || ($IF_NONE_MATCH == ($etag."-gzip")))
+	{
+		header('HTTP/1.1 304 Not Modified');
+		exit();	
+	}
+}
+
+if(!defined('e_NOCACHE'))
+{
+	header("Cache-Control: must-revalidate");	
+}
 
 $pref['compression_level'] = 6;
 $browser_support = FALSE;
@@ -306,6 +321,7 @@ if(ini_get("zlib.output_compression") == '' && function_exists("gzencode"))
 if(varset($pref['compress_output'],false) && $server_support == true && $browser_support == true) 
 {
 	$level = intval($pref['compression_level']);
+	header("ETag: \"{$etag}-gzip\"");
 	$page = gzencode($page, $level);
 	header("Content-Encoding: gzip", true);
 	header("Content-Length: ".strlen($page), true);
@@ -313,6 +329,15 @@ if(varset($pref['compress_output'],false) && $server_support == true && $browser
 } 
 else 
 {
+	if($browser_support==TRUE) 
+	{
+		header("ETag: \"{$etag}-gzip\"");	
+	}
+	else
+	{
+		header("ETag: \"{$etag}\"");	
+	}
+	
 	header("Content-Length: ".strlen($page), true);
 	echo $page;
 }