Fix a number of whitespace issues in various parts of the code, add validation to most calls on the test and take a first stab at implementing the reconnection pipe blocking.

It didn't seem straightforward to use any of the existing process calls, so I have added a new command to command_t and friends called detach. This instructs the socket_base to remove the pipe from it's pipe list. The session base stores a copy of the outpipe, and will resend the bind command on reconnection. This should allow balancing again.

src/command.hpp

@@ -47,6 +47,7 @@ namespace zmq
             own,
             attach,
             bind,
+            detach,
             activate_read,
             activate_write,
             hiccup,
@@ -88,6 +89,11 @@ namespace zmq
                 zmq::pipe_t *pipe;
             } bind;
             
+            //  Sent from session to socket to disconnect a pipe 
+            struct {
+                zmq::pipe_t *pipe;
+            } detach;
+
             //  Sent by pipe writer to inform dormant pipe reader that there
             //  are messages in the pipe.
             struct {

src/object.cpp

@@ -92,6 +92,11 @@ void zmq::object_t::process_command (command_t &cmd_)
         process_seqnum ();
         break;
 
+    case command_t::detach:
+        process_detach (cmd_.args.detach.pipe);
+        process_seqnum ();
+        break;
+
     case command_t::hiccup:
         process_hiccup (cmd_.args.hiccup.pipe);
         break;
@@ -211,6 +216,15 @@ void zmq::object_t::send_bind (own_t *destination_, pipe_t *pipe_,
     send_command (cmd);
 }
 
+void zmq::object_t::send_detach (own_t *destination_, pipe_t *pipe_)
+{
+    command_t cmd;
+    cmd.destination = destination_;
+    cmd.type = command_t::detach;
+    cmd.args.detach.pipe = pipe_;
+    send_command (cmd);
+}
+
 void zmq::object_t::send_activate_read (pipe_t *destination_)
 {
     command_t cmd;
@@ -331,6 +345,11 @@ void zmq::object_t::process_bind (pipe_t *pipe_)
     zmq_assert (false);
 }
 
+void zmq::object_t::process_detach (pipe_t *pipe_)
+{
+    zmq_assert (false);
+}
+
 void zmq::object_t::process_activate_read ()
 {
     zmq_assert (false);

src/object.hpp

@@ -78,6 +78,7 @@ namespace zmq
              zmq::i_engine *engine_, bool inc_seqnum_ = true);
         void send_bind (zmq::own_t *destination_, zmq::pipe_t *pipe_,
              bool inc_seqnum_ = true);
+        void send_detach (own_t *destination_, pipe_t *pipe_);
         void send_activate_read (zmq::pipe_t *destination_);
         void send_activate_write (zmq::pipe_t *destination_,
              uint64_t msgs_read_);
@@ -99,6 +100,7 @@ namespace zmq
         virtual void process_own (zmq::own_t *object_);
         virtual void process_attach (zmq::i_engine *engine_);
         virtual void process_bind (zmq::pipe_t *pipe_);
+        virtual void process_detach (zmq::pipe_t *pipe_);
         virtual void process_activate_read ();
         virtual void process_activate_write (uint64_t msgs_read_);
         virtual void process_hiccup (void *pipe_);

src/session_base.cpp

@@ -306,9 +306,15 @@ void zmq::session_base_t::process_attach (i_engine *engine_)
         zmq_assert (!pipe);
         pipe = pipes [0];
 
+        //  Remember the remote end of the pipe if required
+        if (options.delay_attach_on_connect == 1)
+            outpipe = pipes [1];
+
         //  Ask socket to plug into the pipe.
         send_bind (socket, pipes [1]);
     }
+        else if (outpipe && (options.delay_attach_on_connect == 1)) 
+        send_bind (socket, outpipe);
 
     //  Plug in the engine.
     zmq_assert (!engine);
@@ -405,6 +411,11 @@ void zmq::session_base_t::detached ()
     //  the socket object to resend all the subscriptions.
     if (pipe && (options.type == ZMQ_SUB || options.type == ZMQ_XSUB))
         pipe->hiccup ();
+        
+    //  For delayed connect situations, hiccup the socket to have it
+    //  pause usage of this pipe
+    if (outpipe && options.delay_attach_on_connect == 1) 
+        send_detach(socket, outpipe);
 }
 
 void zmq::session_base_t::start_connecting (bool wait_)

src/session_base.hpp

@@ -53,9 +53,6 @@ namespace zmq
         //  To be used once only, when creating the session.
         void attach_pipe (zmq::pipe_t *pipe_);
 
-        // To be used once only, for delayed connection
-        void onconnect_attach_pipe (pipe_t *pipe_);
-
         //  Following functions are the interface exposed towards the engine.
         virtual int read (msg_t *msg_);
         virtual int write (msg_t *msg_);
@@ -107,6 +104,9 @@ namespace zmq
         //  Pipe connecting the session to its socket.
         zmq::pipe_t *pipe;
 
+        //  Socket end of pipe, in case of reconnection
+        zmq::pipe_t *outpipe; 
+
         //  This flag is true if the remainder of the message being processed
         //  is still in the in pipe.
         bool incomplete_in;

src/socket_base.cpp

@@ -876,6 +876,17 @@ void zmq::socket_base_t::process_destroy ()
     destroyed = true;
 }
 
+void zmq::socket_base_t::process_detach (pipe_t *pipe_)
+{
+    //  If we are blocking connecting threads, drop this one
+    if (options.delay_attach_on_connect == 1) {
+        zmq_assert (pipe_);
+        pipes.erase (pipe_);
+        //  Let derived sockets know we're ditching this pipe
+        xterminated (pipe_);
+    }
+}
+
 int zmq::socket_base_t::xsetsockopt (int option_, const void *optval_,
     size_t optvallen_)
 {

src/socket_base.hpp

@@ -185,6 +185,9 @@ namespace zmq
         void process_bind (zmq::pipe_t *pipe_);
         void process_term (int linger_);
 
+        // Allow blocking reconnecting pipes
+        void process_detach (pipe_t *pipe_);
+
         //  Socket's mailbox object.
         mailbox_t mailbox;
 

tests/test_connect_delay.cpp

@@ -36,25 +36,33 @@ int main (int argc, char *argv [])
     int seen = 0;
 
     void *context = zmq_ctx_new();
+    assert (context);
     void *to = zmq_socket(context, ZMQ_PULL);
+    assert (to);
+    
     val = 0;
-    zmq_setsockopt(to, ZMQ_LINGER, &val, sizeof(val));
-    zmq_bind(to, "tcp://*:5555");
+    rc = zmq_setsockopt(to, ZMQ_LINGER, &val, sizeof(val));
+    assert (rc == 0);
+    rc = zmq_bind(to, "tcp://*:5555");
+    assert (rc == 0);
 
     //  Create a socket pushing to two endpoints - only 1 message should arrive.
     void *from = zmq_socket (context, ZMQ_PUSH);
+    assert(from);
+    
     val = 0;
-    zmq_setsockopt(from, ZMQ_LINGER, &val, sizeof(val));
-    rc = zmq_connect(from, "tcp://localhost:5556");
+    zmq_setsockopt (from, ZMQ_LINGER, &val, sizeof(val));
+    rc = zmq_connect (from, "tcp://localhost:5556");
     assert (rc == 0);
-    rc = zmq_connect(from, "tcp://localhost:5555");
+    rc = zmq_connect (from, "tcp://localhost:5555");
     assert (rc == 0);
 
     for (int i = 0; i < 10; ++i)
     {
         std::string message("message ");
         message += ('0' + i);
-        zmq_send(from, message.data(), message.size(), 0);
+        rc = zmq_send (from, message.data(), message.size(), 0);
+        assert(rc >= 0);
     }
     
     sleep(1);
@@ -62,7 +70,7 @@ int main (int argc, char *argv [])
     for (int i = 0; i < 10; ++i)
     {
         memset(&buffer, 0, sizeof(buffer));
-        rc = zmq_recv(to, &buffer, sizeof(buffer), ZMQ_DONTWAIT);
+        rc = zmq_recv (to, &buffer, sizeof(buffer), ZMQ_DONTWAIT);
         if( rc == -1) 
             break;
         seen++;
@@ -81,27 +89,39 @@ int main (int argc, char *argv [])
     context = zmq_ctx_new();
     std::cout << "  Rerunning with DELAY_ATTACH_ON_CONNECT\n";
     
-    to = zmq_socket(context, ZMQ_PULL);
-    zmq_bind(to, "tcp://*:5560");
+    to = zmq_socket (context, ZMQ_PULL);
+    assert (to);
+    rc = zmq_bind (to, "tcp://*:5560");
+    assert(rc == 0);
+    
     val = 0;
-    zmq_setsockopt(to, ZMQ_LINGER, &val, sizeof(val));
+    rc = zmq_setsockopt (to, ZMQ_LINGER, &val, sizeof(val));
+    assert (rc == 0);
     
     //  Create a socket pushing to two endpoints - all messages should arrive.
     from = zmq_socket (context, ZMQ_PUSH);
+    assert (from);
+    
     val = 0;
-    zmq_setsockopt(from, ZMQ_LINGER, &val, sizeof(val));
-    val = 1;
-    zmq_setsockopt(from, ZMQ_DELAY_ATTACH_ON_CONNECT, &val, sizeof(val));
-    rc = zmq_connect(from, "tcp://localhost:5561");
+    rc = zmq_setsockopt (from, ZMQ_LINGER, &val, sizeof(val));
     assert (rc == 0);
-    rc = zmq_connect(from, "tcp://localhost:5560");
+    
+    val = 1;
+    rc = zmq_setsockopt (from, ZMQ_DELAY_ATTACH_ON_CONNECT, &val, sizeof(val));
+    assert (rc == 0);
+    
+    rc = zmq_connect (from, "tcp://localhost:5561");
+    assert (rc == 0);
+    
+    rc = zmq_connect (from, "tcp://localhost:5560");
     assert (rc == 0);
 
     for (int i = 0; i < 10; ++i)
     {
         std::string message("message ");
         message += ('0' + i);
-        zmq_send(from, message.data(), message.size(), 0);
+        rc = zmq_send (from, message.data(), message.size(), 0);
+        assert (rc >= 0);
     }
     
     sleep(1);
@@ -110,13 +130,9 @@ int main (int argc, char *argv [])
     for (int i = 0; i < 10; ++i)
     {
         memset(&buffer, 0, sizeof(buffer));
-        rc = zmq_recv(to, &buffer, sizeof(buffer), ZMQ_DONTWAIT);
-        if( rc == -1) {
-            break;
+        rc = zmq_recv (to, &buffer, sizeof(buffer), ZMQ_DONTWAIT);
+        assert (rc != -1);
     }
-        seen++;
-    }
-    assert (seen == 10);
 
     rc = zmq_close (from);
     assert (rc == 0);