Patches from sub-forward branch incorporated

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

1 files changed, 148 insertions, 12 deletions

diff --git a/src/xsub.cpp b/src/xsub.cpp
index 6928d82..729f6a4 100644
--- a/src/xsub.cpp
+++ b/src/xsub.cpp
@@ -24,19 +24,30 @@
 #include "err.hpp"
 
 zmq::xsub_t::xsub_t (class ctx_t *parent_, uint32_t tid_) :
-    socket_base_t (parent_, tid_)
+    socket_base_t (parent_, tid_),
+    has_message (false),
+    more (false)
 {
     options.type = ZMQ_XSUB;
+    int rc = message.init ();
+    errno_assert (rc == 0);
 }
 
 zmq::xsub_t::~xsub_t ()
 {
+    int rc = message.close ();
+    errno_assert (rc == 0);
 }
 
 void zmq::xsub_t::xattach_pipe (pipe_t *pipe_, const blob_t &peer_identity_)
 {
     zmq_assert (pipe_);
     fq.attach (pipe_);
+    dist.attach (pipe_);
+
+    //  Send all the cached subscriptions to the new upstream peer.
+    subscriptions.apply (send_subscription, pipe_);
+    pipe_->flush ();
 }
 
 void zmq::xsub_t::xread_activated (pipe_t *pipe_)
@@ -44,20 +55,49 @@ void zmq::xsub_t::xread_activated (pipe_t *pipe_)
     fq.activated (pipe_);
 }
 
+void zmq::xsub_t::xwrite_activated (pipe_t *pipe_)
+{
+    dist.activated (pipe_);
+}
+
 void zmq::xsub_t::xterminated (pipe_t *pipe_)
 {
     fq.terminated (pipe_);
+    dist.terminated (pipe_);
 }
 
-int zmq::xsub_t::xsend (msg_t *msg_, int options_)
+void zmq::xsub_t::xhiccuped (pipe_t *pipe_)
 {
-    //  TODO: Once we'll send the subscription upstream here. For now
-    //  just empty the message.
-    int rc = msg_->close ();
-    errno_assert (rc == 0);
-    rc = msg_->init ();
-    errno_assert (rc == 0);
-    return 0;
+    //  Send all the cached subscriptions to the hiccuped pipe.
+    subscriptions.apply (send_subscription, pipe_);
+    pipe_->flush ();
+}
+
+int zmq::xsub_t::xsend (msg_t *msg_, int flags_)
+{
+    size_t size = msg_->size ();
+    unsigned char *data = (unsigned char*) msg_->data ();
+
+    // Malformed subscriptions.
+    if (size < 1 || (*data != 0 && *data != 1)) {
+        errno = EINVAL;
+        return -1;
+    }
+
+    // Process the subscription.
+    if (*data == 1) {
+        if (subscriptions.add (data + 1, size - 1))
+            return dist.send (msg_, flags_);
+        else
+            return 0;
+    }
+    else if (*data == 0) {
+        if (subscriptions.rm (data + 1, size - 1))
+            return dist.send (msg_, flags_);
+        else
+            return 0;
+    }
+    zmq_assert (false);
 }
 
 bool zmq::xsub_t::xhas_out ()
@@ -66,13 +106,109 @@ bool zmq::xsub_t::xhas_out ()
     return true;
 }
 
-int zmq::xsub_t::xrecv (class msg_t *msg_, int flags_)
+int zmq::xsub_t::xrecv (msg_t *msg_, int flags_)
 {
-    return fq.recv (msg_, flags_);
+    //  If there's already a message prepared by a previous call to zmq_poll,
+    //  return it straight ahead.
+    if (has_message) {
+        int rc = msg_->move (message);
+        errno_assert (rc == 0);
+        has_message = false;
+        more = msg_->flags () & msg_t::more;
+        return 0;
+    }
+
+    //  TODO: This can result in infinite loop in the case of continuous
+    //  stream of non-matching messages which breaks the non-blocking recv
+    //  semantics.
+    while (true) {
+
+        //  Get a message using fair queueing algorithm.
+        int rc = fq.recv (msg_, flags_);
+
+        //  If there's no message available, return immediately.
+        //  The same when error occurs.
+        if (rc != 0)
+            return -1;
+
+        //  Check whether the message matches at least one subscription.
+        //  Non-initial parts of the message are passed 
+        if (more || match (msg_)) {
+            more = msg_->flags () & msg_t::more;
+            return 0;
+        }
+
+        //  Message doesn't match. Pop any remaining parts of the message
+        //  from the pipe.
+        while (msg_->flags () & msg_t::more) {
+            rc = fq.recv (msg_, ZMQ_DONTWAIT);
+            zmq_assert (rc == 0);
+        }
+    }
 }
 
 bool zmq::xsub_t::xhas_in ()
 {
-    return fq.has_in ();
+    //  There are subsequent parts of the partly-read message available.
+    if (more)
+        return true;
+
+    //  If there's already a message prepared by a previous call to zmq_poll,
+    //  return straight ahead.
+    if (has_message)
+        return true;
+
+    //  TODO: This can result in infinite loop in the case of continuous
+    //  stream of non-matching messages.
+    while (true) {
+
+        //  Get a message using fair queueing algorithm.
+        int rc = fq.recv (&message, ZMQ_DONTWAIT);
+
+        //  If there's no message available, return immediately.
+        //  The same when error occurs.
+        if (rc != 0) {
+            zmq_assert (errno == EAGAIN);
+            return false;
+        }
+
+        //  Check whether the message matches at least one subscription.
+        if (match (&message)) {
+            has_message = true;
+            return true;
+        }
+
+        //  Message doesn't match. Pop any remaining parts of the message
+        //  from the pipe.
+        while (message.flags () & msg_t::more) {
+            rc = fq.recv (&message, ZMQ_DONTWAIT);
+            zmq_assert (rc == 0);
+        }
+    }
+}
+
+bool zmq::xsub_t::match (msg_t *msg_)
+{
+    return subscriptions.check ((unsigned char*) msg_->data (), msg_->size ());
 }
 
+void zmq::xsub_t::send_subscription (unsigned char *data_, size_t size_,
+    void *arg_)
+{
+    pipe_t *pipe = (pipe_t*) arg_;
+
+    //  Create the subsctription message.
+    msg_t msg;
+    int rc = msg.init_size (size_ + 1);
+    zmq_assert (rc == 0);
+    unsigned char *data = (unsigned char*) msg.data ();
+    data [0] = 1;
+    memcpy (data + 1, data_, size_);
+
+    //  Send it to the pipe.
+    bool sent = pipe->write (&msg);
+    zmq_assert (sent);
+    msg.close ();
+}
+
+