ZMQ_FILTER socket option added

This option is a performance tweak. In devices XSUB socket filters
the messages just to send them to XPUB socket which filters them
once more. Setting ZMQ_FILTER option to 0 allows to switch the
filtering in XSUB socket off.

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

1 files changed, 2 insertions, 2 deletions

diff --git a/src/xsub.cpp b/src/xsub.cpp
index a847d7f..60ba598 100644
--- a/src/xsub.cpp
+++ b/src/xsub.cpp
@@ -133,7 +133,7 @@ int zmq::xsub_t::xrecv (msg_t *msg_, int flags_)
 
         //  Check whether the message matches at least one subscription.
         //  Non-initial parts of the message are passed 
-        if (more || match (msg_)) {
+        if (more || !options.filter || match (msg_)) {
             more = msg_->flags () & msg_t::more;
             return 0;
         }
@@ -173,7 +173,7 @@ bool zmq::xsub_t::xhas_in ()
         }
 
         //  Check whether the message matches at least one subscription.
-        if (match (&message)) {
+        if (!options.filter || match (&message)) {
             has_message = true;
             return true;
         }