Experimental patch to partially protect against simultaneous edit bug by

adding the conflict check to the UPDATE on cur and moving it up before
the INSERT to old. Should throw edit conflict instead of overwriting
a different revision.

diff --git a/includes/Article.php b/includes/Article.php
index da63a4b..caf5773 100644 (file)
--- a/includes/Article.php
+++ b/includes/Article.php
@@ -421,6 +421,23 @@ class Article {
                        $this->mCountAdjustment = $this->isCountable( $text )
                          - $this->isCountable( $oldtext );
 
+                       $now = wfTimestampNow();
+                       $won = wfInvertTimestamp( $now );
+                       $sql = "UPDATE cur SET cur_text='" . wfStrencode( $text ) .
+                         "',cur_comment='" .  wfStrencode( $summary ) .
+                         "',cur_minor_edit={$me2}, cur_user=" . $wgUser->getID() .
+                         ",cur_timestamp='{$now}',cur_user_text='" .
+                         wfStrencode( $wgUser->getName() ) .
+                         "',cur_is_redirect={$redir}, cur_is_new=0, cur_touched='{$now}', inverse_timestamp='{$won}' " .
+                         "WHERE cur_id=" . $this->getID() .
+                         " AND cur_timestamp='" . $this->getTimestamp() . "'";
+                       $res = wfQuery( $sql, $fname );
+                       
+                       if( wfAffectedRows() == 0 ) {
+                               /* Belated edit conflict! Run away!! */
+                               return false;
+                       }
+
                        $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 (" .
@@ -435,17 +452,6 @@ class Article {
                        $res = wfQuery( $sql, $fname );
                        $oldid = wfInsertID( $res );
 
-                       $now = wfTimestampNow();
-                       $won = wfInvertTimestamp( $now );
-                       $sql = "UPDATE cur SET cur_text='" . wfStrencode( $text ) .
-                         "',cur_comment='" .  wfStrencode( $summary ) .
-                         "',cur_minor_edit={$me2}, cur_user=" . $wgUser->getID() .
-                         ",cur_timestamp='{$now}',cur_user_text='" .
-                         wfStrencode( $wgUser->getName() ) .
-                         "',cur_is_redirect={$redir}, cur_is_new=0, cur_touched='{$now}', inverse_timestamp='{$won}' " .
-                         "WHERE cur_id=" . $this->getID();
-                       wfQuery( $sql, $fname );
-
                        $sql = "INSERT INTO recentchanges (rc_timestamp,rc_cur_time," .
                          "rc_namespace,rc_title,rc_new,rc_minor,rc_bot,rc_cur_id,rc_user," .
                          "rc_user_text,rc_comment,rc_this_oldid,rc_last_oldid) VALUES (" .
@@ -480,7 +486,8 @@ class Article {
                        }
                }
 
-               $this->showArticle( $text, wfMsg( "updated" ) ); 
+               $this->showArticle( $text, wfMsg( "updated" ) );
+               return true;
        }
 
        # After we've either updated or inserted the article, update

diff --git a/includes/DatabaseFunctions.php b/includes/DatabaseFunctions.php
index bd767e8..a1c4388 100644 (file)
--- a/includes/DatabaseFunctions.php
+++ b/includes/DatabaseFunctions.php
@@ -116,6 +116,7 @@ function wfInsertId() { return mysql_insert_id( wfGetDB() ); }
 function wfDataSeek( $res, $row ) { return mysql_data_seek( $res, $row ); }
 function wfLastErrno() { return mysql_errno(); }
 function wfLastError() { return mysql_error(); }
+function wfAffectedRows() { return mysql_affected_rows( wfGetDB() ); }
 
 function wfLastDBquery()
 {

diff --git a/includes/EditPage.php b/includes/EditPage.php
index f529053..7f430d6 100644 (file)
--- a/includes/EditPage.php
+++ b/includes/EditPage.php
@@ -153,8 +153,10 @@ class EditPage {
                        }
                        if ( ! $isConflict ) {
                                # All's well: update the article here
-                               $this->mArticle->updateArticle( $wpTextbox1, $wpSummary, $wpMinoredit, $wpWatchthis, $wpSection );
-                               return;
+                               if($this->mArticle->updateArticle( $wpTextbox1, $wpSummary, $wpMinoredit, $wpWatchthis, $wpSection ))
+                                       return;
+                               else
+                                       $isConflict = true;
                        }
                }
                # First time through: get contents, set time for conflict