Significantly reworked the monitoring infrastructure with a more granular per…

Significantly reworked the monitoring infrastructure with a more granular per socket API and to play well with monitoring endpoints in application threads

doc/Makefile.am

 MAN3 = zmq_bind.3 zmq_close.3 zmq_connect.3 zmq_proxy.3 \
     zmq_ctx_new.3 zmq_ctx_destroy.3 zmq_ctx_get.3 zmq_ctx_set.3 \
-    zmq_init.3 zmq_term.3 zmq_ctx_set_monitor.3\
+    zmq_init.3 zmq_term.3 \
     zmq_msg_close.3 zmq_msg_copy.3 zmq_msg_data.3 zmq_msg_init.3 \
     zmq_msg_init_data.3 zmq_msg_init_size.3 zmq_msg_move.3 zmq_msg_size.3 \
     zmq_msg_send.3 zmq_msg_recv.3 \
     zmq_poll.3 zmq_recv.3 zmq_send.3 zmq_setsockopt.3 zmq_socket.3 \
-    zmq_strerror.3 zmq_version.3 zmq_getsockopt.3 zmq_errno.3 \
+    zmq_socket_monitor.3 zmq_strerror.3 zmq_version.3 zmq_getsockopt.3 zmq_errno.3 \
     zmq_sendmsg.3 zmq_recvmsg.3 zmq_msg_get.3 zmq_msg_set.3 zmq_msg_more.3
 MAN7 = zmq.7 zmq_tcp.7 zmq_pgm.7 zmq_epgm.7 zmq_inproc.7 zmq_ipc.7
 

include/zmq.h

@@ -278,8 +278,16 @@ ZMQ_EXPORT int zmq_msg_set (zmq_msg_t *msg, int option, int optval);
 #define ZMQ_EVENT_CLOSE_FAILED 256
 #define ZMQ_EVENT_DISCONNECTED 512
 
+#define ZMQ_EVENT_ALL ( ZMQ_EVENT_CONNECTED | ZMQ_EVENT_CONNECT_DELAYED | \
+                        ZMQ_EVENT_CONNECT_RETRIED | ZMQ_EVENT_LISTENING | \
+                        ZMQ_EVENT_BIND_FAILED | ZMQ_EVENT_ACCEPTED | \
+                        ZMQ_EVENT_ACCEPT_FAILED | ZMQ_EVENT_CLOSED | \
+                        ZMQ_EVENT_CLOSE_FAILED | ZMQ_EVENT_DISCONNECTED )
+
 /*  Socket event data (union member per event)                                */
-typedef union {
+typedef struct {
+    int event;
+    union {
     struct {
         char *addr;
         int fd;
@@ -320,12 +328,8 @@ typedef union {
         char *addr;
         int fd;
     } disconnected;
-} zmq_event_data_t;
-
-/*  Callback template for socket state changes                                */
-typedef void (zmq_monitor_fn) (void *s, int event, zmq_event_data_t *data);
-
-ZMQ_EXPORT int zmq_ctx_set_monitor (void *context, zmq_monitor_fn *monitor);
+    } data;
+} zmq_event_t;
 
 ZMQ_EXPORT void *zmq_socket (void *, int type);
 ZMQ_EXPORT int zmq_close (void *s);
@@ -339,6 +343,7 @@ ZMQ_EXPORT int zmq_unbind (void *s, const char *addr);
 ZMQ_EXPORT int zmq_disconnect (void *s, const char *addr);
 ZMQ_EXPORT int zmq_send (void *s, const void *buf, size_t len, int flags);
 ZMQ_EXPORT int zmq_recv (void *s, void *buf, size_t len, int flags);
+ZMQ_EXPORT int zmq_socket_monitor (void *s, const char *addr, int events);
 
 ZMQ_EXPORT int zmq_sendmsg (void *s, zmq_msg_t *msg, int flags);
 ZMQ_EXPORT int zmq_recvmsg (void *s, zmq_msg_t *msg, int flags);

src/ctx.cpp

@@ -45,8 +45,7 @@ zmq::ctx_t::ctx_t () :
     slot_count (0),
     slots (NULL),
     max_sockets (ZMQ_MAX_SOCKETS_DFLT),
-    io_thread_count (ZMQ_IO_THREADS_DFLT),
-    monitor_fn (NULL)
+    io_thread_count (ZMQ_IO_THREADS_DFLT)
 {
 }
 
@@ -126,12 +125,6 @@ int zmq::ctx_t::terminate ()
     return 0;
 }
 
-int zmq::ctx_t::monitor (zmq_monitor_fn *monitor_)
-{
-    monitor_fn = monitor_;
-    return 0;
-}
-
 int zmq::ctx_t::set (int option_, int optval_)
 {
     int rc = 0;
@@ -353,67 +346,6 @@ zmq::endpoint_t zmq::ctx_t::find_endpoint (const char *addr_)
      return endpoint;
 }
 
-void zmq::ctx_t::monitor_event (zmq::socket_base_t *socket_, int event_, ...)
-{
-    va_list args;
-    va_start (args, event_);
-    va_monitor_event (socket_, event_, args);
-    va_end (args);
-}
-
-void zmq::ctx_t::va_monitor_event (zmq::socket_base_t *socket_, int event_, va_list args_)
-{
-    if (monitor_fn != NULL) {
-        zmq_event_data_t data;
-        memset(&data, 0, sizeof (zmq_event_data_t));
-        switch (event_) {
-        case ZMQ_EVENT_CONNECTED:
-            data.connected.addr = va_arg (args_, char*);
-            data.connected.fd = va_arg (args_, int);
-            break;
-        case ZMQ_EVENT_CONNECT_DELAYED:
-            data.connect_delayed.addr = va_arg (args_, char*);
-            data.connect_delayed.err = va_arg (args_, int);
-            break;
-        case ZMQ_EVENT_CONNECT_RETRIED:
-            data.connect_retried.addr = va_arg (args_, char*);
-            data.connect_retried.interval = va_arg (args_, int);
-            break;
-        case ZMQ_EVENT_LISTENING:
-            data.listening.addr = va_arg (args_, char*);
-            data.listening.fd = va_arg (args_, int);
-            break;
-        case ZMQ_EVENT_BIND_FAILED:
-            data.bind_failed.addr = va_arg (args_, char*);
-            data.bind_failed.err = va_arg (args_, int);
-            break;
-        case ZMQ_EVENT_ACCEPTED:
-            data.accepted.addr = va_arg (args_, char*);
-            data.accepted.fd = va_arg (args_, int);
-            break;
-        case ZMQ_EVENT_ACCEPT_FAILED:
-            data.accept_failed.addr = va_arg (args_, char*);
-            data.accept_failed.err = va_arg (args_, int);
-            break;
-        case ZMQ_EVENT_CLOSED:
-            data.closed.addr = va_arg (args_, char*);
-            data.closed.fd = va_arg (args_, int);
-            break;
-        case ZMQ_EVENT_CLOSE_FAILED:
-            data.close_failed.addr = va_arg (args_, char*);
-            data.close_failed.err = va_arg (args_, int);
-            break;
-        case ZMQ_EVENT_DISCONNECTED:
-            data.disconnected.addr = va_arg (args_, char*);
-            data.disconnected.fd = va_arg (args_, int);
-            break;
-        default:
-            zmq_assert (false);
-        }
-        monitor_fn ((void *)socket_, event_, &data);
-    }
-}
-
 //  The last used socket ID, or 0 if no socket was used so far. Note that this
 //  is a global variable. Thus, even sockets created in different contexts have
 //  unique IDs.

src/ctx.hpp

@@ -95,11 +95,6 @@ namespace zmq
         void unregister_endpoints (zmq::socket_base_t *socket_);
         endpoint_t find_endpoint (const char *addr_);
 
-        // Monitoring specific
-        int monitor (zmq_monitor_fn *monitor_);
-        void monitor_event (zmq::socket_base_t *socket_, int event_, ...);
-        void va_monitor_event (zmq::socket_base_t *socket_, int event_, va_list args_);
-
         enum {
             term_tid = 0,
             reaper_tid = 1
@@ -169,9 +164,6 @@ namespace zmq
         //  Synchronisation of access to context options.
         mutex_t opt_sync;
 
-        // Monitoring callback
-        zmq_monitor_fn *monitor_fn;
-
         ctx_t (const ctx_t&);
         const ctx_t &operator = (const ctx_t&);
     };

src/ipc_connecter.cpp

@@ -56,6 +56,7 @@ zmq::ipc_connecter_t::ipc_connecter_t (class io_thread_t *io_thread_,
     zmq_assert (addr);
     zmq_assert (addr->protocol == "ipc");
     addr->to_string (endpoint);
+    socket = session-> get_socket();
 }
 
 zmq::ipc_connecter_t::~ipc_connecter_t ()
@@ -121,7 +122,7 @@ void zmq::ipc_connecter_t::out_event ()
     //  Shut the connecter down.
     terminate ();
 
-    session->monitor_event (ZMQ_EVENT_CONNECTED, endpoint.c_str(), fd);
+    socket->event_connected (endpoint.c_str(), fd);
 }
 
 void zmq::ipc_connecter_t::timer_event (int id_)
@@ -148,7 +149,7 @@ void zmq::ipc_connecter_t::start_connecting ()
         handle = add_fd (s);
         handle_valid = true;
         set_pollout (handle);
-        session->monitor_event (ZMQ_EVENT_CONNECT_DELAYED, endpoint.c_str(), zmq_errno());
+        socket->event_connect_delayed (endpoint.c_str(), zmq_errno());
     }
 
     //  Handle any other error condition by eventual reconnect.
@@ -163,7 +164,7 @@ void zmq::ipc_connecter_t::add_reconnect_timer()
 {
     int rc_ivl = get_new_reconnect_ivl();
     add_timer (rc_ivl, reconnect_timer_id);
-    session->monitor_event (ZMQ_EVENT_CONNECT_RETRIED, endpoint.c_str(), rc_ivl);
+    socket->event_connect_retried (endpoint.c_str(), rc_ivl);
     timer_started = true;
 }
 
@@ -224,7 +225,7 @@ int zmq::ipc_connecter_t::close ()
     zmq_assert (s != retired_fd);
     int rc = ::close (s);
     errno_assert (rc == 0);
-    session->monitor_event (ZMQ_EVENT_CLOSED, endpoint.c_str(), s);
+    socket->event_closed (endpoint.c_str(), s);
     s = retired_fd;
     return 0;
 }

src/ipc_connecter.hpp

@@ -113,6 +113,9 @@ namespace zmq
         // String representation of endpoint to connect to
         std::string endpoint;
 
+        // Socket
+        zmq::socket_base_t *socket;
+
         ipc_connecter_t (const ipc_connecter_t&);
         const ipc_connecter_t &operator = (const ipc_connecter_t&);
     };

src/ipc_listener.cpp

@@ -76,7 +76,7 @@ void zmq::ipc_listener_t::in_event ()
     //  If connection was reset by the peer in the meantime, just ignore it.
     //  TODO: Handle specific errors like ENFILE/EMFILE etc.
     if (fd == retired_fd) {
-        socket->monitor_event (ZMQ_EVENT_ACCEPT_FAILED, endpoint.c_str(), zmq_errno());
+        socket->event_accept_failed (endpoint.c_str(), zmq_errno());
         return;
     }
 
@@ -96,7 +96,7 @@ void zmq::ipc_listener_t::in_event ()
     session->inc_seqnum ();
     launch_child (session);
     send_attach (session, engine, false);
-    socket->monitor_event (ZMQ_EVENT_ACCEPTED, endpoint.c_str(), fd);
+    socket->event_accepted (endpoint.c_str(), fd);
 }
 
 int zmq::ipc_listener_t::get_address (std::string &addr_)
@@ -155,7 +155,7 @@ int zmq::ipc_listener_t::set_address (const char *addr_)
     if (rc != 0)
         goto error;
 
-    socket->monitor_event (ZMQ_EVENT_LISTENING, endpoint.c_str(), s);
+    socket->event_listening (endpoint.c_str(), s);
     return 0;
 
 error:
@@ -178,12 +178,12 @@ int zmq::ipc_listener_t::close ()
     if (has_file && !filename.empty ()) {
         rc = ::unlink(filename.c_str ());
         if (rc != 0) {
-            socket->monitor_event (ZMQ_EVENT_CLOSE_FAILED, endpoint.c_str(), zmq_errno());
+            socket->event_close_failed (endpoint.c_str(), zmq_errno());
             return -1;
         }
     }
 
-    socket->monitor_event (ZMQ_EVENT_CLOSED, endpoint.c_str(), s);
+    socket->event_closed (endpoint.c_str(), s);
     return 0;
 }
 

src/session_base.cpp

@@ -23,7 +23,6 @@
 #include <stdarg.h>
 
 #include "session_base.hpp"
-#include "socket_base.hpp"
 #include "i_engine.hpp"
 #include "err.hpp"
 #include "pipe.hpp"
@@ -286,17 +285,9 @@ void zmq::session_base_t::hiccuped (pipe_t *)
     zmq_assert (false);
 }
 
-void zmq::session_base_t::monitor_event (int event_, ...)
+zmq::socket_base_t *zmq::session_base_t::get_socket ()
 {
-    va_list args;
-    va_start (args, event_);
-    va_monitor_event (event_, args);
-    va_end (args);
-}
-
-void zmq::session_base_t::va_monitor_event (int event_, va_list args)
-{
-    socket->va_monitor_event (event_, args);
+    return socket;
 }
 
 void zmq::session_base_t::process_plug ()

src/session_base.hpp

@@ -31,6 +31,7 @@
 #include "pipe.hpp"
 #include "i_msg_source.hpp"
 #include "i_msg_sink.hpp"
+#include "socket_base.hpp"
 
 namespace zmq
 {
@@ -75,8 +76,7 @@ namespace zmq
         void hiccuped (zmq::pipe_t *pipe_);
         void terminated (zmq::pipe_t *pipe_);
 
-        void monitor_event (int event_, ...);
-        void va_monitor_event (int event_, va_list args);
+        socket_base_t *get_socket ();
 
     protected:
 

src/socket_base.cpp

@@ -130,13 +130,16 @@ zmq::socket_base_t::socket_base_t (ctx_t *parent_, uint32_t tid_, int sid_) :
     destroyed (false),
     last_tsc (0),
     ticks (0),
-    rcvmore (false)
+    rcvmore (false),
+    monitor_socket (NULL),
+    monitor_events (0)
 {
     options.socket_id = sid_;
 }
 
 zmq::socket_base_t::~socket_base_t ()
 {
+    stop_monitor ();
     zmq_assert (destroyed);
 }
 
@@ -354,7 +357,7 @@ int zmq::socket_base_t::bind (const char *addr_)
         int rc = listener->set_address (address.c_str ());
         if (rc != 0) {
             delete listener;
-            monitor_event (ZMQ_EVENT_BIND_FAILED, addr_, zmq_errno());
+            event_bind_failed (addr_, zmq_errno());
             return -1;
         }
 
@@ -373,7 +376,7 @@ int zmq::socket_base_t::bind (const char *addr_)
         int rc = listener->set_address (address.c_str ());
         if (rc != 0) {
             delete listener;
-            monitor_event (ZMQ_EVENT_BIND_FAILED, addr_, zmq_errno());
+            event_bind_failed (addr_, zmq_errno());
             return -1;
         }
 
@@ -845,6 +848,7 @@ void zmq::socket_base_t::process_stop ()
     //  We'll remember the fact so that any blocking call is interrupted and any
     //  further attempt to use the socket will return ETERM. The user is still
     //  responsible for calling zmq_close on the socket though!
+    stop_monitor ();
     ctx_terminated = true;
 }
 
@@ -996,15 +1000,172 @@ void zmq::socket_base_t::extract_flags (msg_t *msg_)
     rcvmore = msg_->flags () & msg_t::more ? true : false;
 }
 
-void zmq::socket_base_t::monitor_event (int event_, ...)
+int zmq::socket_base_t::monitor (const char *addr_, int events_)
 {
-    va_list args;
-    va_start (args, event_);
-    va_monitor_event(event_, args);
-    va_end (args);
+    int rc;
+    if (unlikely (ctx_terminated)) {
+        errno = ETERM;
+        return -1;
+    }
+
+    // Support deregistering monitoring endpoints as well
+    if (addr_ == NULL) {
+        stop_monitor ();
+        return 0;
+    }
+
+    //  Parse addr_ string.
+    std::string protocol;
+    std::string address;
+    rc = parse_uri (addr_, protocol, address);
+    if (rc != 0)
+        return -1;
+
+    rc = check_protocol (protocol);
+    if (rc != 0)
+        return -1;
+
+    // Event notification only supported over inproc://
+    if (protocol != "inproc") {
+        errno = EPROTONOSUPPORT;
+        return -1;
+    }
+
+    // Register events to monitor
+    monitor_events = events_;
+
+    monitor_socket = zmq_socket( get_ctx (), ZMQ_PAIR);
+    if (monitor_socket == NULL)
+        return -1;
+
+    // Never block context termination on pending event messages
+    int linger = 0;
+    rc = zmq_setsockopt (monitor_socket, ZMQ_LINGER, &linger, sizeof (linger));
+    if (rc == -1)
+         stop_monitor ();
+
+    // Spawn the monitor socket endpoint
+    rc = zmq_bind (monitor_socket, addr_);
+    if (rc == -1)
+         stop_monitor ();
+    return rc;
+}
+
+void zmq::socket_base_t::event_connected (const char *addr_, int fd_)
+{
+    zmq_event_t event;
+    if (!(monitor_events & ZMQ_EVENT_CONNECTED)) return;
+    event.event = ZMQ_EVENT_CONNECTED;
+    event.data.connected.addr = (char *)addr_;
+    event.data.connected.fd = fd_;
+    monitor_event (event);
 }
 
-void zmq::socket_base_t::va_monitor_event (int event_, va_list args)
+void zmq::socket_base_t::event_connect_delayed (const char *addr_, int err_)
 {
-    get_ctx ()->va_monitor_event (this, event_, args);
+    zmq_event_t event;
+    if (!(monitor_events & ZMQ_EVENT_CONNECT_DELAYED)) return;
+    event.event = ZMQ_EVENT_CONNECT_DELAYED;
+    event.data.connected.addr = (char *)addr_;
+    event.data.connect_delayed.err = err_;
+    monitor_event (event);
+}
+
+void zmq::socket_base_t::event_connect_retried (const char *addr_, int interval_)
+{
+    zmq_event_t event;
+    if (!(monitor_events & ZMQ_EVENT_CONNECT_RETRIED)) return;
+    event.event = ZMQ_EVENT_CONNECT_RETRIED;
+    event.data.connected.addr = (char *)addr_;
+    event.data.connect_retried.interval = interval_;
+    monitor_event (event);
+}
+
+void zmq::socket_base_t::event_listening (const char *addr_, int fd_)
+{
+    zmq_event_t event;
+    if (!(monitor_events & ZMQ_EVENT_LISTENING)) return;
+    event.event = ZMQ_EVENT_LISTENING;
+    event.data.connected.addr = (char *)addr_;
+    event.data.listening.fd = fd_;
+    monitor_event (event);
+}
+
+void zmq::socket_base_t::event_bind_failed (const char *addr_, int err_)
+{
+    zmq_event_t event;
+    if (!(monitor_events & ZMQ_EVENT_BIND_FAILED)) return;
+    event.event = ZMQ_EVENT_BIND_FAILED;
+    event.data.connected.addr = (char *)addr_;
+    event.data.bind_failed.err = err_;
+    monitor_event (event);
+}
+
+void zmq::socket_base_t::event_accepted (const char *addr_, int fd_)
+{
+    zmq_event_t event;
+    if (!(monitor_events & ZMQ_EVENT_ACCEPTED)) return;
+    event.event = ZMQ_EVENT_ACCEPTED;
+    event.data.connected.addr = (char *)addr_;
+    event.data.accepted.fd = fd_;
+    monitor_event (event);
+}
+
+void zmq::socket_base_t::event_accept_failed (const char *addr_, int err_)
+{
+    zmq_event_t event;
+    if (!(monitor_events & ZMQ_EVENT_ACCEPT_FAILED)) return;
+    event.event = ZMQ_EVENT_ACCEPT_FAILED;
+    event.data.connected.addr = (char *)addr_;
+    event.data.accept_failed.err= err_;
+    monitor_event (event);
+}
+
+void zmq::socket_base_t::event_closed (const char *addr_, int fd_)
+{
+    zmq_event_t event;
+    if (!(monitor_events & ZMQ_EVENT_CLOSED)) return;
+    event.event = ZMQ_EVENT_CLOSED;
+    event.data.connected.addr = (char *)addr_;
+    event.data.closed.fd = fd_;
+    monitor_event (event);
+}
+        
+void zmq::socket_base_t::event_close_failed (const char *addr_, int err_)
+{
+    zmq_event_t event;
+    if (!(monitor_events & ZMQ_EVENT_CLOSE_FAILED)) return;
+    event.event = ZMQ_EVENT_CLOSE_FAILED;
+    event.data.connected.addr = (char *)addr_;
+    event.data.close_failed.err = err_;
+    monitor_event (event);
+}
+
+void zmq::socket_base_t::event_disconnected (const char *addr_, int fd_)
+{
+    zmq_event_t event;
+    if (!(monitor_events & ZMQ_EVENT_DISCONNECTED)) return;
+    event.event = ZMQ_EVENT_DISCONNECTED;
+    event.data.connected.addr = (char *)addr_;
+    event.data.disconnected.fd = fd_;
+    monitor_event (event);
+}
+
+void zmq::socket_base_t::monitor_event (zmq_event_t event_)
+{
+    zmq_msg_t msg;
+    if (!monitor_socket) return;
+    zmq_msg_init_size (&msg, sizeof (event_));
+    memcpy (zmq_msg_data (&msg), &event_, sizeof (event_));
+    zmq_sendmsg (monitor_socket, &msg, 0);
+    zmq_msg_close (&msg);
+}
+
+void zmq::socket_base_t::stop_monitor()
+{
+    if (monitor_socket) {
+        zmq_close (monitor_socket);
+        monitor_socket = NULL;
+        monitor_events = 0;
+    }
 }
\ No newline at end of file

src/socket_base.hpp

@@ -102,8 +102,18 @@ namespace zmq
         void lock();
         void unlock();
 
-        void monitor_event (int event_, ...);
-        void va_monitor_event (int event_, va_list args);
+        int monitor(const char *endpoint_, int events_);
+
+        void event_connected(const char *addr_, int fd_);
+        void event_connect_delayed(const char *addr_, int err_);
+        void event_connect_retried(const char *addr_, int interval_);
+        void event_listening(const char *addr_, int fd_);
+        void event_bind_failed(const char *addr_, int err_);
+        void event_accepted(const char *addr_, int fd_);
+        void event_accept_failed(const char *addr_, int err_);
+        void event_closed(const char *addr_, int fd_);        
+        void event_close_failed(const char *addr_, int fd_);  
+        void event_disconnected(const char *addr_, int fd_); 
 
     protected:
 
@@ -138,6 +148,12 @@ namespace zmq
         //  Delay actual destruction of the socket.
         void process_destroy ();
 
+        // Socket event data dispath
+        void monitor_event (zmq_event_t data_);
+
+        // Monitor socket cleanup
+        void stop_monitor ();
+
     private:
         //  Creates new endpoint ID and adds the endpoint to the map.
         void add_endpoint (const char *addr_, own_t *endpoint_);
@@ -210,6 +226,12 @@ namespace zmq
         //  Improves efficiency of time measurement.
         clock_t clock;
 
+        // Monitor socket;
+        void *monitor_socket;
+
+        // Bitmask of events being monitored
+        int monitor_events;
+
         socket_base_t (const socket_base_t&);
         const socket_base_t &operator = (const socket_base_t&);
         mutex_t sync;

src/stream_engine.cpp

@@ -62,7 +62,8 @@ zmq::stream_engine_t::stream_engine_t (fd_t fd_, const options_t &options_, cons
     session (NULL),
     options (options_),
     endpoint (endpoint_),
-    plugged (false)
+    plugged (false),
+    socket (NULL)
 {
     //  Put the socket into non-blocking mode.
     unblock_socket (s);
@@ -126,6 +127,7 @@ void zmq::stream_engine_t::plug (io_thread_t *io_thread_,
     zmq_assert (!session);
     zmq_assert (session_);
     session = session_;
+    socket = session-> get_socket ();
 
     //  Connect to I/O threads poller object.
     io_object_t::plug (io_thread_);
@@ -445,7 +447,7 @@ int zmq::stream_engine_t::push_msg (msg_t *msg_)
 void zmq::stream_engine_t::error ()
 {
     zmq_assert (session);
-    session->monitor_event (ZMQ_EVENT_DISCONNECTED, endpoint.c_str(), s);
+    socket->event_disconnected (endpoint.c_str(), s);
     session->detach ();
     unplug ();
     delete this;

src/stream_engine.hpp

@@ -31,6 +31,7 @@
 #include "i_encoder.hpp"
 #include "i_decoder.hpp"
 #include "options.hpp"
+#include "socket_base.hpp"
 #include "../include/zmq.h"
 
 namespace zmq
@@ -133,6 +134,9 @@ namespace zmq
 
         bool plugged;
 
+        // Socket
+        zmq::socket_base_t *socket;
+
         stream_engine_t (const stream_engine_t&);
         const stream_engine_t &operator = (const stream_engine_t&);
     };

src/tcp_connecter.cpp

@@ -66,6 +66,7 @@ zmq::tcp_connecter_t::tcp_connecter_t (class io_thread_t *io_thread_,
     zmq_assert (addr);
     zmq_assert (addr->protocol == "tcp");
     addr->to_string (endpoint);
+    socket = session-> get_socket();
 }
 
 zmq::tcp_connecter_t::~tcp_connecter_t ()
@@ -135,7 +136,7 @@ void zmq::tcp_connecter_t::out_event ()
     //  Shut the connecter down.
     terminate ();
 
-    session->monitor_event (ZMQ_EVENT_CONNECTED, endpoint.c_str(), fd);
+    socket->event_connected (endpoint.c_str(), fd);
 }
 
 void zmq::tcp_connecter_t::timer_event (int id_)
@@ -162,7 +163,7 @@ void zmq::tcp_connecter_t::start_connecting ()
         handle = add_fd (s);
         handle_valid = true;
         set_pollout (handle);
-        session->monitor_event (ZMQ_EVENT_CONNECT_DELAYED, endpoint.c_str(), zmq_errno());
+        socket->event_connect_delayed (endpoint.c_str(), zmq_errno());
     }
 
     //  Handle any other error condition by eventual reconnect.
@@ -177,7 +178,7 @@ void zmq::tcp_connecter_t::add_reconnect_timer()
 {
     int rc_ivl = get_new_reconnect_ivl();
     add_timer (rc_ivl, reconnect_timer_id);
-    session->monitor_event (ZMQ_EVENT_CONNECT_RETRIED, endpoint.c_str(), rc_ivl);
+    socket->event_connect_retried (endpoint.c_str(), rc_ivl);
     timer_started = true;
 }
 
@@ -303,6 +304,6 @@ void zmq::tcp_connecter_t::close ()
     int rc = ::close (s);
     errno_assert (rc == 0);
 #endif
-    session->monitor_event (ZMQ_EVENT_CLOSED, endpoint.c_str(), s);
+    socket->event_closed (endpoint.c_str(), s);
     s = retired_fd;
 }

src/tcp_connecter.hpp

@@ -111,6 +111,9 @@ namespace zmq
         // String representation of endpoint to connect to
         std::string endpoint;
 
+        // Socket
+        zmq::socket_base_t *socket;
+
         tcp_connecter_t (const tcp_connecter_t&);
         const tcp_connecter_t &operator = (const tcp_connecter_t&);
     };

src/tcp_listener.cpp

@@ -85,7 +85,7 @@ void zmq::tcp_listener_t::in_event ()
     //  If connection was reset by the peer in the meantime, just ignore it.
     //  TODO: Handle specific errors like ENFILE/EMFILE etc.
     if (fd == retired_fd) {
-        socket->monitor_event (ZMQ_EVENT_ACCEPT_FAILED, endpoint.c_str(), zmq_errno());
+        socket->event_accept_failed (endpoint.c_str(), zmq_errno());
         return;
     }
 
@@ -108,7 +108,7 @@ void zmq::tcp_listener_t::in_event ()
     session->inc_seqnum ();
     launch_child (session);
     send_attach (session, engine, false);
-    socket->monitor_event (ZMQ_EVENT_ACCEPTED, endpoint.c_str(), fd);
+    socket->event_accepted (endpoint.c_str(), fd);
 }
 
 void zmq::tcp_listener_t::close ()
@@ -121,7 +121,7 @@ void zmq::tcp_listener_t::close ()
     int rc = ::close (s);
     errno_assert (rc == 0);
 #endif
-    socket->monitor_event (ZMQ_EVENT_CLOSED, endpoint.c_str(), s);
+    socket->event_closed (endpoint.c_str(), s);
     s = retired_fd;
 }
 
@@ -223,7 +223,7 @@ int zmq::tcp_listener_t::set_address (const char *addr_)
         goto error;
 #endif
 
-    socket->monitor_event (ZMQ_EVENT_LISTENING, endpoint.c_str(), s);
+    socket->event_listening (endpoint.c_str(), s);
     return 0;
 
 error:

src/zmq.cpp

@@ -210,15 +210,6 @@ int zmq_ctx_get (void *ctx_, int option_)
     return ((zmq::ctx_t*) ctx_)->get (option_);
 }
 
-int zmq_ctx_set_monitor (void *ctx_, zmq_monitor_fn *monitor_)
-{
-    if (!ctx_ || !((zmq::ctx_t*) ctx_)->check_tag ()) {
-        errno = EFAULT;
-        return -1;
-    }
-    return ((zmq::ctx_t*) ctx_)->monitor (monitor_);
-}
-
 //  Stable/legacy context API
 
 void *zmq_init (int io_threads_)
@@ -284,6 +275,17 @@ int zmq_getsockopt (void *s_, int option_, void *optval_, size_t *optvallen_)
     return result;
 }
 
+int zmq_socket_monitor (void *s_, const char *addr_, int events_)
+{
+    if (!s_ || !((zmq::socket_base_t*) s_)->check_tag ()) {
+        errno = ENOTSOCK;
+        return -1;
+    }
+    zmq::socket_base_t *s = (zmq::socket_base_t *) s_;
+    int result = s->monitor (addr_, events_);
+    return result;
+}
+
 int zmq_bind (void *s_, const char *addr_)
 {
     if (!s_ || !((zmq::socket_base_t*) s_)->check_tag ()) {