From 80dc53604bbcf8f39c0e9e7727928f5a0fde296a Mon Sep 17 00:00:00 2001
From: Brion Vibber <brion@users.mediawiki.org>
Date: Sun, 4 Jan 2004 03:35:00 +0000
Subject: [PATCH] Add $wgCompressRevisions option to compress old revisions on
 page save. (Off by default.) Also change default of $wgUseGzip to be on if
 zlib is available (this affects the file cache only).

---
 includes/Article.php         | 23 ++++++++++++++++++++---
 includes/DefaultSettings.php |  8 +++++++-
 2 files changed, 27 insertions(+), 4 deletions(-)

diff --git a/includes/Article.php b/includes/Article.php
index 0c7ba47f06..5f8a57beff 100644
--- a/includes/Article.php
+++ b/includes/Article.php
@@ -38,7 +38,8 @@ class Article {
 
 	/* static */ function getRevisionText( $row, $prefix = "old_" ) {
 		# Deal with optional compression of archived pages.
-		# This can be done periodically via maintenance/compressOld.php
+		# This can be done periodically via maintenance/compressOld.php, and
+		# as pages are saved if $wgCompressRevisions is set.
 		$text = $prefix . "text";
 		$flags = $prefix . "flags";
 		if( isset( $row->$flags ) && (false !== strpos( $row->$flags, "gzip" ) ) ) {
@@ -50,6 +51,19 @@ class Article {
 		return false;
 	}
 	
+	/* static */ function compressRevisionText( &$text ) {
+		global $wgCompressRevisions;
+		if( !$wgCompressRevisions ) {
+			return "";
+		}
+		if( !function_exists( "gzdeflate" ) ) {
+			wfDebug( "Article::compressRevisionText() -- no zlib support, not compressing\n" );
+			return "";
+		}
+		$text = gzdeflate( $text );
+		return "gzip";
+	}
+	
 	# Note that getContent/loadContent may follow redirects if
 	# not told otherwise, and so may cause a change to mTitle.
 
@@ -479,9 +493,12 @@ class Article {
 				return false;
 			}
 
+			# This overwrites $oldtext if revision compression is on
+			$flags = Article::compressRevisionText( $oldtext );
+			
 			$sql = "INSERT INTO old (old_namespace,old_title,old_text," .
 			  "old_comment,old_user,old_user_text,old_timestamp," .
-			  "old_minor_edit,inverse_timestamp) VALUES (" .
+			  "old_minor_edit,inverse_timestamp,old_flags) VALUES (" .
 			  $this->mTitle->getNamespace() . ", '" .
 			  wfStrencode( $this->mTitle->getDBkey() ) . "', '" .
 			  wfStrencode( $oldtext ) . "', '" .
@@ -489,7 +506,7 @@ class Article {
 			  $this->getUser() . ", '" .
 			  wfStrencode( $this->getUserText() ) . "', '" .
 			  $this->getTimestamp() . "', " . $me1 . ", '" .
-			  wfInvertTimestamp( $this->getTimestamp() ) . "')";
+			  wfInvertTimestamp( $this->getTimestamp() ) . "','$flags')";
 			$res = wfQuery( $sql, DB_WRITE, $fname );
 			$oldid = wfInsertID( $res );
 
diff --git a/includes/DefaultSettings.php b/includes/DefaultSettings.php
index f1b66a25bf..0980a999fd 100644
--- a/includes/DefaultSettings.php
+++ b/includes/DefaultSettings.php
@@ -150,7 +150,13 @@ $wgDisableAnonTalk = false;
 # We can serve pages compressed in order to save bandwidth,
 # but this will increase CPU usage.
 # Requires zlib support enabled in PHP.
-$wgUseGzip = false;
+$wgUseGzip = function_exists( "gzencode" );
+
+# We can also compress text in the old revisions table. If this is set on,
+# old revisions will be compressed on page save if zlib support is available.
+# Any compressed revisions will be decompressed on load regardless of this
+# setting *but will not be readable at all* if zlib support is not available.
+$wgCompressRevisions = false;
 
 # This is the list of preferred extensions for uploading files. Uploading
 # files with extensions not in this list will trigger a warning.
-- 
2.20.1