vscard_common: VSCMsgInit capabilities and magic

add capabilities bitmap and magic in VSCMsgInit

1 files changed, 7 insertions, 1 deletions

diff --git a/vscard_common.h b/vscard_common.h
index b092980..0a2ec36 100644
--- a/vscard_common.h
+++ b/vscard_common.h
@@ -74,10 +74,16 @@ typedef struct VSCMsgHeader {
 } VSCMsgHeader;
 
 /* VSCMsgInit               Client <-> Host
- * Host replies with allocated reader id in ReaderAddResponse
+ * Client sends, Host replies with same.
+ * This is meant to be a handshake and capabilities announcement.
+ * It is not meant to be used for negotiation, i.e. sending more then
+ * once from any side, but could be used for that in the future.
  * */
 typedef struct VSCMsgInit {
+    uint32_t   magic;
     uint32_t   version;
+    uint32_t   capabilities[1]; /* client must check length,
+                                   array may grow in the future*/
 } VSCMsgInit;
 
 /* VSCMsgError              Client <-> Host