From 10694373e34c0dba4cd6e64a3bd2209cd1cd9913 Mon Sep 17 00:00:00 2001
From: Marc Sune <marc@voltanet.io>
Date: Fri, 14 Jul 2017 15:35:32 +0200
Subject: [PATCH] Fix ROUTER's xhas_out() in MANDATORY mode
Before this commit, xhas_out() was returning true regardless. This
was correct before the ZMQ_ROUTER_MANDATORY flag as introduced.
However, ZMQ_POLLOUT.
With this commit, _if_ ZMQ_ROUTER_MANDATORY is set, xhas_out() will
return false if ALL peer's outgoing pipes are full.
There is an outstanding high-level design question:
If ZMQ_ROUTER_MANDATORY is set, and zmq_poll() waits for ZMQ_POLLOUT
events, zmq_poll() will immediately wake up if only 1 pipe has
room to send, regardless of the peer, creating a busy loop of
zmq_poll() wake-up, zmq_send() (EAGAIN). There is no way for
the application to selectively wait for ZMQ_POLLOUT for specific
peer(s), which seems somehow necessary in ZMQ_ROUTER_MANDATORY.
This discussion will be addressed in a separate issue.
Signed-off-by: Marc Sune <marc@voltanet.io>
Signed-off-by: Fredi Raspall <fredi@voltanet.io>
---
src/router.cpp | 17 +++++++++++++----
1 file changed, 13 insertions(+), 4 deletions(-)
diff --git a/src/router.cpp b/src/router.cpp
index fc46ae19..45a4f51c 100644
--- a/src/router.cpp
+++ b/src/router.cpp
@@ -385,10 +385,19 @@ bool zmq::router_t::xhas_in ()
bool zmq::router_t::xhas_out ()
{
- // In theory, ROUTER socket is always ready for writing. Whether actual
- // attempt to write succeeds depends on whitch pipe the message is going
- // to be routed to.
- return true;
+ // In theory, ROUTER socket is always ready for writing (except when
+ // MANDATORY is set). Whether actual attempt to write succeeds depends
+ // on whitch pipe the message is going to be routed to.
+
+ if(!mandatory)
+ return true;
+
+ bool has_out = false;
+ outpipes_t::iterator it;
+ for (it = outpipes.begin (); it != outpipes.end (); ++it)
+ has_out |= it->second.pipe->check_hwm();
+
+ return has_out;
}
zmq::blob_t zmq::router_t::get_credential () const