Patches from sub-forward branch incorporated

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

src/xpub.cpp

@@ -18,6 +18,8 @@
     along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
+#include <string.h>
+
 #include "xpub.hpp"
 #include "pipe.hpp"
 #include "err.hpp"
@@ -37,6 +39,12 @@ void zmq::xpub_t::xattach_pipe (pipe_t *pipe_, const blob_t &peer_identity_)
 {
     zmq_assert (pipe_);
     dist.attach (pipe_);
+    fq.attach (pipe_);
+}
+
+void zmq::xpub_t::xread_activated (pipe_t *pipe_)
+{
+    fq.activated (pipe_);
 }
 
 void zmq::xpub_t::xwrite_activated (pipe_t *pipe_)
@@ -46,11 +54,37 @@ void zmq::xpub_t::xwrite_activated (pipe_t *pipe_)
 
 void zmq::xpub_t::xterminated (pipe_t *pipe_)
 {
+    //  Remove the pipe from the trie. If there are topics that nobody
+    //  is interested in anymore, send corresponding unsubscriptions
+    //  upstream.
+    subscriptions.rm (pipe_, send_unsubscription, this);
+
     dist.terminated (pipe_);
+    fq.terminated (pipe_);
 }
 
 int zmq::xpub_t::xsend (msg_t *msg_, int flags_)
 {
+    //  First, process any (un)subscriptions from downstream.
+    msg_t sub;
+    sub.init ();
+    while (true) {
+
+        //  Grab next subscription.
+        pipe_t *pipe;
+        int rc = fq.recvpipe (&sub, 0, &pipe);
+        if (rc != 0 && errno == EAGAIN)
+            break;
+        errno_assert (rc == 0);
+
+        //  Apply the subscription to the trie. If it's not a duplicate,
+        //  store it so that it can be passed to used on next recv call.
+        if (apply_subscription (&sub, pipe) && options.type != ZMQ_PUB)
+            pending.push_back (blob_t ((unsigned char*) sub.data (),
+                sub.size ()));
+    }
+    sub.close ();
+    
     return dist.send (msg_, flags_);
 }
 
@@ -61,12 +95,92 @@ bool zmq::xpub_t::xhas_out ()
 
 int zmq::xpub_t::xrecv (msg_t *msg_, int flags_)
 {
-    errno = EAGAIN;
-    return -1;
+    //  If there is at least one 
+    if (!pending.empty ()) {
+        int rc = msg_->close ();
+        errno_assert (rc == 0);
+        rc = msg_->init_size (pending.front ().size ());
+        errno_assert (rc == 0);
+        memcpy (msg_->data (), pending.front ().data (),
+            pending.front ().size ());
+        pending.pop_front ();
+        return 0;
+    }
+
+    //  Grab and apply next subscription.
+    pipe_t *pipe;
+    int rc = fq.recvpipe (msg_, 0, &pipe);
+    if (rc != 0)
+        return -1;
+    if (!apply_subscription (msg_, pipe)) {
+//  TODO: This should be a loop rather!
+        msg_->close ();
+        msg_->init ();
+        errno = EAGAIN;
+        return -1;
+    }
+    return 0;
 }
 
 bool zmq::xpub_t::xhas_in ()
 {
-    return false;
+    if (!pending.empty ())
+        return true;
+
+    //  Even if there are subscriptions in the fair-queuer they may be
+    //  duplicates. Thus, we have to check by hand wheter there is any
+    //  subscription available to pass upstream.
+    //  First, process any (un)subscriptions from downstream.
+    msg_t sub;
+    sub.init ();
+    while (true) {
+
+        //  Grab next subscription.
+        pipe_t *pipe;
+        int rc = fq.recvpipe (&sub, 0, &pipe);
+        if (rc != 0 && errno == EAGAIN) {
+            sub.close ();
+            return false;
+        }
+        errno_assert (rc == 0);
+
+        //  Apply the subscription to the trie. If it's not a duplicate store
+        //  it so that it can be passed to used on next recv call.
+        if (apply_subscription (&sub, pipe) && options.type != ZMQ_PUB) {
+            pending.push_back (blob_t ((unsigned char*) sub.data (),
+                sub.size ()));
+            sub.close ();
+            return true;
+        }
+    }
+}
+
+bool zmq::xpub_t::apply_subscription (msg_t *sub_, pipe_t *pipe_)
+{
+    unsigned char *data = (unsigned char*) sub_->data ();
+    size_t size = sub_->size ();
+    zmq_assert (size > 0 && (*data == 0 || *data == 1));
+
+    if (*data == 0)
+        return subscriptions.rm (data + 1, size - 1, pipe_);
+    else
+        return subscriptions.add (data + 1, size - 1, pipe_);
+}
+
+void zmq::xpub_t::send_unsubscription (unsigned char *data_, size_t size_,
+    void *arg_)
+{
+    xpub_t *self = (xpub_t*) arg_;
+
+    if (self->options.type != ZMQ_PUB) {
+
+		//  Place the unsubscription to the queue of pending (un)sunscriptions
+		//  to be retrived by the user later on.
+		xpub_t *self = (xpub_t*) arg_;
+		blob_t unsub (size_ + 1, 0);
+		unsub [0] = 0;
+		memcpy (&unsub [1], data_, size_);
+		self->pending.push_back (unsub);
+    }
 }