ZP-968 Use 0x80000 flag when setting up exporter in Ping.

Released under the Affero GNU General Public License (AGPL) version 3.

src/backend/kopano/exporter.php

@@ -152,8 +152,10 @@ class ExportChangesICS implements IExportChanges{
             }
         }
 
-        if($this->flags & BACKEND_DISCARD_DATA)
+        if($this->flags & BACKEND_DISCARD_DATA) {
             $this->exporterflags |= SYNC_CATCHUP;
+            $this->exporterflags |= SYNC_STATE_READONLY;
+        }
 
         // Put the state information in a stream that can be used by ICS
         $stream = mapi_stream_create();
@@ -323,6 +325,11 @@ class ExportChangesICS implements IExportChanges{
      * @return array
      */
     public function Synchronize() {
+        if ($this->flags & BACKEND_DISCARD_DATA) {
+            ZLog::Write(LOGLEVEL_WARN, 'ExportChangesICS->Synchronize(): not supported in combination with the BACKEND_DISCARD_DATA flag.');
+            return false;
+        }
+
         if ($this->exporter) {
             return mapi_exportchanges_synchronize($this->exporter);
         }

src/backend/kopano/mapi/mapidefs.php

@@ -628,6 +628,7 @@ define('SYNC_PROGRESS_MODE'                      ,0x8000);        // AirMapi pro
 define('SYNC_FXRECOVERMODE'                      ,0x10000);
 define('SYNC_DEFER_CONFIG'                       ,0x20000);
 define('SYNC_FORCE_UNICODE'                      ,0x40000);       // Forces server to return Unicode properties
+define('SYNC_STATE_READONLY'                     ,0x80000);       // Server will not update the states in the DB, setting up exporter with this flag states are read only
 
 define('EMS_AB_ADDRESS_LOOKUP'                   ,0x00000001);    // Flag for resolvename to resolve only exact matches