Ticket #14912: plugin-versions.diff

wp-includes/plugin.php

@@ -668 +668 @@
 }
 
 /**
+ * Set the update hook for a plugin.
+ * 
+ * Registers the update hook that will be called when the user updates the
+ * plugin to a newer version than previously installed.  
+ *
+ * This function performs calls action called update_plugin- suffixed by the name
+ * of the plugin.  Plugins can hook update scripts to this action in order to 
+ * clean up options or extra database tables across versions.
+ *
+ * @since 3.1
+ *
+ * @param string $file
+ * @param callback $callback The function to run when the hook is called.
+ * @param string $version The version number to which the plugin is updating.
+ */
+function register_update_hook($file, $callback, $version) {
+        $file = plugin_basename($file);
+
+        if(is_multisite()) {
+                $current_vers = get_site_option( 'active_plugin_versions', array() );
+        } else {
+                $current_vers = get_option( 'active_plugin_versions', array() );
+        }
+        
+        if(version_compare($version, $current_vers[$file], '>')) {
+                call_user_func_array( $callback, array($version, $current_vers[$file]) );
+                
+                $current_vers[$file] = $version;
+        }
+        
+        if(is_multisite()) {
+                update_site_option( 'active_plugin_versions', $current_vers );
+        } else {
+                update_option( 'active_plugin_versions', $current_vers );
+        }
+}
+
+/**
  * Calls the 'all' hook, which will process the functions hooked into it.
  *
  * The 'all' hook passes all of the arguments or parameters that were used for