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, 1 deletions

diff --git a/src/encoder.cpp b/src/encoder.cpp
index 6d09384..8689e45 100644
--- a/src/encoder.cpp
+++ b/src/encoder.cpp
@@ -20,6 +20,7 @@
 
 #include "encoder.hpp"
 #include "session_base.hpp"
+#include "likely.hpp"
 #include "wire.hpp"
 
 zmq::encoder_t::encoder_t (size_t bufsize_) :
@@ -62,7 +63,14 @@ bool zmq::encoder_t::message_ready ()
     //  Note that new state is set only if write is successful. That way
     //  unsuccessful write will cause retry on the next state machine
     //  invocation.
-    if (!session || !session->read (&in_progress)) {
+    if (unlikely (!session)) {
+        rc = in_progress.init ();
+        errno_assert (rc == 0);
+        return false;
+    }
+    rc = session->read (&in_progress);
+    if (unlikely (rc != 0)) {
+        errno_assert (errno == EAGAIN);
         rc = in_progress.init ();
         errno_assert (rc == 0);
         return false;