Check message syntax in REQ asynchronously

This patch adds support for checking messages as they arrive
(as opposed to when they are recv'd by the user) and drop
the connection if they are malformed.

It also uses this new feature to check for validity of inbound
messages in REQ socket.

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/src/encoder.hpp b/src/encoder.hpp
index f7e3cbc..949cbdc 100644
--- a/src/encoder.hpp
+++ b/src/encoder.hpp
@@ -142,11 +142,20 @@ namespace zmq
 
     private:
 
+        //  Where to get the data to write from.
         unsigned char *write_pos;
+
+        //  How much data to write before next step should be executed.
         size_t to_write;
+
+        //  Next step. If set to NULL, it means that associated data stream
+        //  is dead.
         step_t next;
+
+        //  If true, first byte of the message is being written.
         bool beginning;
 
+        //  The buffer for encoded data.
         size_t bufsize;
         unsigned char *buf;