[Phpwiki-talk] WikiDB.php caching fix part 1 of 2

[Charles C. <ch...@ru...>]

A patch to lib/WikiDB.php follows.  This is part 1 of my previous set of fixes to the caching logic. 

This patch ensures that the _pagedata_cache is only updated when the data is read from the database. Without this patch, there is
the possibility that _pagedata_cache will be updated (correctly) due to user action and then later the update will be overwritten
with stale data from the _versiondata_cache. Also fixes some indenting.

Index: WikiDB.php
===================================================================
RCS file: /cvsroot/phpwiki/phpwiki/lib/WikiDB.php,v
retrieving revision 1.124
diff -u -r1.124 WikiDB.php
--- WikiDB.php	29 Jan 2005 20:43:32 -0000	1.124
+++ WikiDB.php	31 Jan 2005 14:52:19 -0000
@@ -2045,8 +2045,9 @@
     }
     
     function get_versiondata($pagename, $version, $need_content = false) {
+		$lastestpagedata = false;
         //  FIXME: Seriously ugly hackage
-	if (USECACHE) {   //temporary - for debugging
+		if (USECACHE) {   //temporary - for debugging
             assert(is_string($pagename) && $pagename != '');
             // there is a bug here somewhere which results in an assertion failure at line 105
             // of ArchiveCleaner.php  It goes away if we use the next line.
@@ -2057,16 +2058,18 @@
                 !(is_array ($cache[$pagename])) || !(is_array ($cache[$pagename][$version]))) {
                 $cache[$pagename][$version][$nc] = 
                     $this->_backend->get_versiondata($pagename, $version, $need_content);
+				$lastestpagedata = true;
                 // If we have retrieved all data, we may as well set the cache for $need_content = false
                 if ($need_content){
                     $cache[$pagename][$version]['0'] =& $cache[$pagename][$version]['1'];
                 }
             }
             $vdata = $cache[$pagename][$version][$nc];
-	} else {
+		} else {
             $vdata = $this->_backend->get_versiondata($pagename, $version, $need_content);
-	}
-        if ($vdata && !empty($vdata['%pagedata'])) {
+			$lastestpagedata = true;
+		}
+        if ($lastestpagedata && $vdata && !empty($vdata['%pagedata'])) {
             $this->_pagedata_cache[$pagename] =& $vdata['%pagedata'];
         }
         return $vdata;