XREP & XREQ socket types added; zmq_queue device added

20 files changed, 490 insertions, 18 deletions

diff --git a/bindings/c/zmq.h b/bindings/c/zmq.h
index f0d59b1..37bad52 100644
--- a/bindings/c/zmq.h
+++ b/bindings/c/zmq.h
@@ -149,8 +149,10 @@ ZMQ_EXPORT int zmq_term (void *context);
 #define ZMQ_SUB 2
 #define ZMQ_REQ 3
 #define ZMQ_REP 4
-#define ZMQ_UPSTREAM 5
-#define ZMQ_DOWNSTREAM 6
+#define ZMQ_XREQ 5
+#define ZMQ_XREP 6
+#define ZMQ_UPSTREAM 7
+#define ZMQ_DOWNSTREAM 8
 
 #define ZMQ_HWM 1
 #define ZMQ_LWM 2
diff --git a/bindings/cl/zeromq.lisp b/bindings/cl/zeromq.lisp
index 03befd5..a8b9c5c 100644
--- a/bindings/cl/zeromq.lisp
+++ b/bindings/cl/zeromq.lisp
@@ -130,8 +130,10 @@
 (defconstant sub 2)
 (defconstant req 3)
 (defconstant rep 4)
-(defconstant upstream 5)
-(defconstant downstream 6)
+(defconstant xreq 5)
+(defconstant xrep 6)
+(defconstant upstream 7)
+(defconstant downstream 8)
 
 (defcfun* ("zmq_socket" socket) :pointer
   (context	:pointer)
diff --git a/bindings/java/org/zmq/Socket.java b/bindings/java/org/zmq/Socket.java
index 935fade..075e322 100644
--- a/bindings/java/org/zmq/Socket.java
+++ b/bindings/java/org/zmq/Socket.java
@@ -34,8 +34,10 @@ public class Socket
     public static final int SUB = 2;
     public static final int REQ = 3;
     public static final int REP = 4;
-    public static final int UPSTREAM = 4;
-    public static final int DOWNSTREAM = 4;
+    public static final int XREQ = 5;
+    public static final int XREP = 6;
+    public static final int UPSTREAM = 7;
+    public static final int DOWNSTREAM = 8;
 
     public static final int HWM = 1;
     public static final int LWM = 2;
diff --git a/bindings/python/pyzmq.cpp b/bindings/python/pyzmq.cpp
index f171eab..75f872d 100644
--- a/bindings/python/pyzmq.cpp
+++ b/bindings/python/pyzmq.cpp
@@ -498,6 +498,12 @@ PyMODINIT_FUNC initlibpyzmq ()
     t = PyInt_FromLong (ZMQ_REP);
     PyDict_SetItemString (dict, "REP", t);
     Py_DECREF (t);
+    t = PyInt_FromLong (ZMQ_XREQ);
+    PyDict_SetItemString (dict, "XREQ", t);
+    Py_DECREF (t);
+    t = PyInt_FromLong (ZMQ_XREP);
+    PyDict_SetItemString (dict, "XREP", t);
+    Py_DECREF (t);
     t = PyInt_FromLong (ZMQ_UPSTREAM);
     PyDict_SetItemString (dict, "UPSTREAM", t);
     Py_DECREF (t);
diff --git a/bindings/ruby/rbzmq.cpp b/bindings/ruby/rbzmq.cpp
index 43baeef..10ff55f 100644
--- a/bindings/ruby/rbzmq.cpp
+++ b/bindings/ruby/rbzmq.cpp
@@ -277,6 +277,8 @@ extern "C" void Init_librbzmq ()
     rb_define_global_const ("PUB", INT2NUM (ZMQ_PUB));
     rb_define_global_const ("REQ", INT2NUM (ZMQ_REQ));
     rb_define_global_const ("REP", INT2NUM (ZMQ_REP));
+    rb_define_global_const ("XREQ", INT2NUM (ZMQ_XREQ));
+    rb_define_global_const ("XREP", INT2NUM (ZMQ_XREP));
     rb_define_global_const ("UPSTREAM", INT2NUM (ZMQ_UPSTREAM));
     rb_define_global_const ("DOWNSTREAM", INT2NUM (ZMQ_DOWNSTREAM));
 
diff --git a/configure.in b/configure.in
index 9d034ed..00c4720 100644
--- a/configure.in
+++ b/configure.in
@@ -520,6 +520,15 @@ if test "x$with_streamer" != "xno"; then
     streamer="yes"
 fi
 
+# Queue device
+queue="no"
+AC_ARG_WITH([queue], [AS_HELP_STRING([--with-queue], 
+    [build queue device [default=no]])], [with_queue=yes], [with_queue=no])
+
+if test "x$with_queue" != "xno"; then
+    queue="yes"
+fi
+
 # Perf
 perf="no"
 AC_ARG_WITH([perf], [AS_HELP_STRING([--with-perf], 
@@ -555,7 +564,8 @@ AM_CONDITIONAL(BUILD_CPP, test "x$cppzmq" = "xyes")
 AM_CONDITIONAL(BUILD_PGM2, test "x$pgm2_ext" = "xyes")
 AM_CONDITIONAL(BUILD_NO_PGM, test "x$pgm2_ext" = "xno")
 AM_CONDITIONAL(BUILD_FORWARDER, test "x$forwarder" = "xyes")
-AM_CONDITIONAL(BUILD_STREAMER, test "x$streamer" = "xyes")  
+AM_CONDITIONAL(BUILD_STREAMER, test "x$streamer" = "xyes")
+AM_CONDITIONAL(BUILD_QUEUE, test "x$queue" = "xyes")  
 AM_CONDITIONAL(BUILD_PERF, test "x$perf" = "xyes")
 AM_CONDITIONAL(BUILD_CHAT, test "x$chat" = "xyes")
 AM_CONDITIONAL(ON_MINGW, test "x$on_mingw32" = "xyes")
@@ -581,7 +591,7 @@ AC_OUTPUT(Makefile src/Makefile man/Makefile bindings/python/Makefile \
     bindings/java/Makefile perf/Makefile perf/c/Makefile perf/cpp/Makefile \
     perf/python/Makefile perf/ruby/Makefile perf/java/Makefile src/libzmq.pc \
     devices/Makefile devices/zmq_forwarder/Makefile \
-    devices/zmq_streamer/Makefile bindings/Makefile \
+    devices/zmq_streamer/Makefile devices/zmq_queue/Makefile bindings/Makefile \
     examples/Makefile examples/chat/Makefile)
 
 AC_MSG_RESULT([])
@@ -616,6 +626,7 @@ AC_MSG_RESULT([     inproc: yes])
 AC_MSG_RESULT([   Devices:])
 AC_MSG_RESULT([     Forwarder: $forwarder])
 AC_MSG_RESULT([     Streamer: $streamer])
+AC_MSG_RESULT([     Queue: $queue])
 AC_MSG_RESULT([   Performance tests: $perf])
 AC_MSG_RESULT([   Examples:])
 AC_MSG_RESULT([     Chat: $chat])
diff --git a/devices/Makefile.am b/devices/Makefile.am
index ab18976..4f20456 100644
--- a/devices/Makefile.am
+++ b/devices/Makefile.am
@@ -6,5 +6,9 @@ if BUILD_STREAMER
 STREAMER_DIR = zmq_streamer
 endif
 
-SUBDIRS = $(FORWARDER_DIR) $(STREAMER_DIR)
-DIST_SUBDIRS = zmq_forwarder zmq_streamer
+if BUILD_QUEUE
+QUEUE_DIR = zmq_queue
+endif
+
+SUBDIRS = $(FORWARDER_DIR) $(STREAMER_DIR) $(QUEUE_DIR)
+DIST_SUBDIRS = zmq_forwarder zmq_streamer zmq_queue
diff --git a/devices/zmq_forwarder/Makefile.am b/devices/zmq_forwarder/Makefile.am
index ff51d88..ee48cda 100644
--- a/devices/zmq_forwarder/Makefile.am
+++ b/devices/zmq_forwarder/Makefile.am
@@ -1,4 +1,4 @@
-INCLUDES = -I$(top_builddir)/bindings/c
+INCLUDES = -I$(top_srcdir)/bindings/cpp -I$(top_srcdir)/bindings/c
 
 bin_PROGRAMS = zmq_forwarder
 
diff --git a/devices/zmq_forwarder/zmq_forwarder.cpp b/devices/zmq_forwarder/zmq_forwarder.cpp
index d29ed62..277af72 100644
--- a/devices/zmq_forwarder/zmq_forwarder.cpp
+++ b/devices/zmq_forwarder/zmq_forwarder.cpp
@@ -29,7 +29,7 @@ int main (int argc, char *argv [])
 
     XMLNode root = XMLNode::parseFile (argv [1]);
     if (root.isEmpty ()) {
-        fprintf (stderr, "configuration file not found\n");
+        fprintf (stderr, "configuration file not found or not an XML file\n");
         return 1;
     }
 
diff --git a/devices/zmq_queue/Makefile.am b/devices/zmq_queue/Makefile.am
new file mode 100644
index 0000000..8d3ec36
--- /dev/null
+++ b/devices/zmq_queue/Makefile.am
@@ -0,0 +1,9 @@
+INCLUDES = -I$(top_srcdir)/bindings/cpp -I$(top_srcdir)/bindings/c
+
+bin_PROGRAMS = zmq_queue
+
+zmq_queue_LDADD = $(top_builddir)/src/libzmq.la
+zmq_queue_SOURCES = zmq_queue.cpp
+zmq_queue_CXXFLAGS = -Wall -pedantic -Werror
+
+
diff --git a/devices/zmq_queue/zmq_queue.cpp b/devices/zmq_queue/zmq_queue.cpp
new file mode 100644
index 0000000..78ccd2d
--- /dev/null
+++ b/devices/zmq_queue/zmq_queue.cpp
@@ -0,0 +1,122 @@
+/*
+    Copyright (c) 2007-2009 FastMQ Inc.
+
+    This file is part of 0MQ.
+
+    0MQ is free software; you can redistribute it and/or modify it under
+    the terms of the Lesser GNU General Public License as published by
+    the Free Software Foundation; either version 3 of the License, or
+    (at your option) any later version.
+
+    0MQ is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    Lesser GNU General Public License for more details.
+
+    You should have received a copy of the Lesser GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "../../bindings/cpp/zmq.hpp"
+#include "../../foreign/xmlParser/xmlParser.cpp"
+
+int main (int argc, char *argv [])
+{
+    if (argc != 2) {
+        fprintf (stderr, "usage: zmq_queue <config-file>\n");
+        return 1;
+    }
+
+    XMLNode root = XMLNode::parseFile (argv [1]);
+    if (root.isEmpty ()) {
+        fprintf (stderr, "configuration file not found or not an XML file\n");
+        return 1;
+    }
+
+    if (strcmp (root.getName (), "queue") != 0) {
+        fprintf (stderr, "root element in the configuration file should be "
+            "named 'queue'\n");
+        return 1;
+    }
+
+    XMLNode in_node = root.getChildNode ("in");
+    if (in_node.isEmpty ()) {
+        fprintf (stderr, "'in' node is missing in the configuration file\n");
+        return 1;
+    }
+
+    XMLNode out_node = root.getChildNode ("out");
+    if (out_node.isEmpty ()) {
+        fprintf (stderr, "'out' node is missing in the configuration file\n");
+        return 1;
+    }
+
+    //  TODO: make the number of I/O threads configurable.
+    zmq::context_t ctx (1, 1);
+    zmq::socket_t in_socket (ctx, ZMQ_XREP);
+    zmq::socket_t out_socket (ctx, ZMQ_XREQ);
+
+    int n = 0;
+    while (true) {
+        XMLNode bind = in_node.getChildNode ("bind", n);
+        if (bind.isEmpty ())
+            break;
+        const char *addr = bind.getAttribute ("addr");
+        if (!addr) {
+            fprintf (stderr, "'bind' node is missing 'addr' attribute\n");
+            return 1;
+        }
+        in_socket.bind (addr);
+        n++;
+    }
+
+    n = 0;
+    while (true) {
+        XMLNode connect = in_node.getChildNode ("connect", n);
+        if (connect.isEmpty ())
+            break;
+        const char *addr = connect.getAttribute ("addr");
+        if (!addr) {
+            fprintf (stderr, "'connect' node is missing 'addr' attribute\n");
+            return 1;
+        }
+        in_socket.connect (addr);
+        n++;
+    }
+
+    n = 0;
+    while (true) {
+        XMLNode bind = out_node.getChildNode ("bind", n);
+        if (bind.isEmpty ())
+            break;
+        const char *addr = bind.getAttribute ("addr");
+        if (!addr) {
+            fprintf (stderr, "'bind' node is missing 'addr' attribute\n");
+            return 1;
+        }
+        out_socket.bind (addr);
+        n++;
+    }
+
+    n = 0;
+    while (true) {
+        XMLNode connect = out_node.getChildNode ("connect", n);
+        if (connect.isEmpty ())
+            break;
+        const char *addr = connect.getAttribute ("addr");
+        if (!addr) {
+            fprintf (stderr, "'connect' node is missing 'addr' attribute\n");
+            return 1;
+        }
+        out_socket.connect (addr);
+        n++;
+    }
+
+    zmq::message_t msg;
+    while (true) {
+        in_socket.recv (&msg);
+        out_socket.send (msg);
+    }
+
+    return 0;
+}
diff --git a/devices/zmq_streamer/Makefile.am b/devices/zmq_streamer/Makefile.am
index e3681bf..9e0ac62 100644
--- a/devices/zmq_streamer/Makefile.am
+++ b/devices/zmq_streamer/Makefile.am
@@ -1,4 +1,4 @@
-INCLUDES = -I$(top_builddir)/bindings/c
+INCLUDES = -I$(top_srcdir)/bindings/cpp -I$(top_srcdir)/bindings/c
 
 bin_PROGRAMS = zmq_streamer
 
diff --git a/devices/zmq_streamer/zmq_streamer.cpp b/devices/zmq_streamer/zmq_streamer.cpp
index 84e6569..c1b88ec 100644
--- a/devices/zmq_streamer/zmq_streamer.cpp
+++ b/devices/zmq_streamer/zmq_streamer.cpp
@@ -29,7 +29,7 @@ int main (int argc, char *argv [])
 
     XMLNode root = XMLNode::parseFile (argv [1]);
     if (root.isEmpty ()) {
-        fprintf (stderr, "configuration file not found\n");
+        fprintf (stderr, "configuration file not found or not an XML file\n");
         return 1;
     }
 
diff --git a/src/Makefile.am b/src/Makefile.am
index bbfa7f5..a733408 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -105,6 +105,8 @@ libzmq_la_SOURCES = app_thread.hpp \
     uuid.hpp \
     windows.hpp \
     wire.hpp \
+    xrep.hpp \
+    xreq.hpp \
     yarray.hpp \
     yarray_item.hpp \
     ypipe.hpp \
@@ -150,6 +152,8 @@ libzmq_la_SOURCES = app_thread.hpp \
     thread.cpp \
     upstream.cpp \
     uuid.cpp \
+    xrep.cpp \
+    xreq.cpp \
     ypollset.cpp \
     zmq.cpp \
     zmq_connecter.cpp \
diff --git a/src/app_thread.cpp b/src/app_thread.cpp
index a671822..308fc36 100644
--- a/src/app_thread.cpp
+++ b/src/app_thread.cpp
@@ -45,6 +45,8 @@
 #include "sub.hpp"
 #include "req.hpp"
 #include "rep.hpp"
+#include "xreq.hpp"
+#include "xrep.hpp"
 #include "upstream.hpp"
 #include "downstream.hpp"
 
@@ -175,6 +177,12 @@ zmq::socket_base_t *zmq::app_thread_t::create_socket (int type_)
     case ZMQ_REP:
         s = new rep_t (this);
         break;
+    case ZMQ_XREQ:
+        s = new xreq_t (this);
+        break;
+    case ZMQ_XREP:
+        s = new xrep_t (this);
+        break;       
     case ZMQ_UPSTREAM:
         s = new upstream_t (this);
         break;
diff --git a/src/pgm_sender.cpp b/src/pgm_sender.cpp
index 19fc0e2..69cb586 100644
--- a/src/pgm_sender.cpp
+++ b/src/pgm_sender.cpp
@@ -46,7 +46,6 @@ zmq::pgm_sender_t::pgm_sender_t (io_thread_t *parent_,
     write_pos (0), 
     first_message_offset (-1)
 {
-
 }
 
 int zmq::pgm_sender_t::init (bool udp_encapsulation_, const char *network_)
@@ -56,7 +55,6 @@ int zmq::pgm_sender_t::init (bool udp_encapsulation_, const char *network_)
 
 void zmq::pgm_sender_t::plug (i_inout *inout_)
 {
-    
     //  Alocate 2 fds for PGM socket.
     int downlink_socket_fd = 0;
     int uplink_socket_fd = 0;
@@ -119,7 +117,6 @@ void zmq::pgm_sender_t::in_event ()
 
 void zmq::pgm_sender_t::out_event ()
 {
-
     //  POLLOUT event from send socket. If write buffer is empty, 
     //  try to read new data from the encoder.
     if (write_pos == write_size) {
@@ -159,7 +156,6 @@ void zmq::pgm_sender_t::out_event ()
 
         write_pos += nbytes;
     }
-
 }
 
 size_t zmq::pgm_sender_t::write_one_pkt_with_offset (unsigned char *data_, 
diff --git a/src/xrep.cpp b/src/xrep.cpp
new file mode 100644
index 0000000..7357967
--- /dev/null
+++ b/src/xrep.cpp
@@ -0,0 +1,95 @@
+/*
+    Copyright (c) 2007-2009 FastMQ Inc.
+
+    This file is part of 0MQ.
+
+    0MQ is free software; you can redistribute it and/or modify it under
+    the terms of the Lesser GNU General Public License as published by
+    the Free Software Foundation; either version 3 of the License, or
+    (at your option) any later version.
+
+    0MQ is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    Lesser GNU General Public License for more details.
+
+    You should have received a copy of the Lesser GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "../bindings/c/zmq.h"
+
+#include "xrep.hpp"
+#include "err.hpp"
+#include "pipe.hpp"
+
+zmq::xrep_t::xrep_t (class app_thread_t *parent_) :
+    socket_base_t (parent_)
+{
+    options.requires_in = true;
+    options.requires_out = true;
+}
+
+zmq::xrep_t::~xrep_t ()
+{
+}
+
+void zmq::xrep_t::xattach_pipes (class reader_t *inpipe_,
+    class writer_t *outpipe_)
+{
+    zmq_assert (false);
+}
+
+void zmq::xrep_t::xdetach_inpipe (class reader_t *pipe_)
+{
+    zmq_assert (false);
+}
+
+void zmq::xrep_t::xdetach_outpipe (class writer_t *pipe_)
+{
+    zmq_assert (false);
+}
+
+void zmq::xrep_t::xkill (class reader_t *pipe_)
+{
+    zmq_assert (false);
+}
+
+void zmq::xrep_t::xrevive (class reader_t *pipe_)
+{
+    zmq_assert (false);
+}
+
+int zmq::xrep_t::xsetsockopt (int option_, const void *optval_,
+    size_t optvallen_)
+{
+    errno = EINVAL;
+    return -1;
+}
+
+int zmq::xrep_t::xsend (zmq_msg_t *msg_, int flags_)
+{
+    zmq_assert (false);
+}
+
+int zmq::xrep_t::xflush ()
+{
+    zmq_assert (false);
+}
+
+int zmq::xrep_t::xrecv (zmq_msg_t *msg_, int flags_)
+{
+    zmq_assert (false);
+}
+
+bool zmq::xrep_t::xhas_in ()
+{
+    zmq_assert (false);
+}
+
+bool zmq::xrep_t::xhas_out ()
+{
+    zmq_assert (false);
+}
+
+
diff --git a/src/xrep.hpp b/src/xrep.hpp
new file mode 100644
index 0000000..de42036
--- /dev/null
+++ b/src/xrep.hpp
@@ -0,0 +1,57 @@
+/*
+    Copyright (c) 2007-2009 FastMQ Inc.
+
+    This file is part of 0MQ.
+
+    0MQ is free software; you can redistribute it and/or modify it under
+    the terms of the Lesser GNU General Public License as published by
+    the Free Software Foundation; either version 3 of the License, or
+    (at your option) any later version.
+
+    0MQ is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    Lesser GNU General Public License for more details.
+
+    You should have received a copy of the Lesser GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef __ZMQ_XREP_HPP_INCLUDED__
+#define __ZMQ_XREP_HPP_INCLUDED__
+
+#include "socket_base.hpp"
+#include "yarray.hpp"
+
+namespace zmq
+{
+
+    class xrep_t : public socket_base_t
+    {
+    public:
+
+        xrep_t (class app_thread_t *parent_);
+        ~xrep_t ();
+
+        //  Overloads of functions from socket_base_t.
+        void xattach_pipes (class reader_t *inpipe_, class writer_t *outpipe_);
+        void xdetach_inpipe (class reader_t *pipe_);
+        void xdetach_outpipe (class writer_t *pipe_);
+        void xkill (class reader_t *pipe_);
+        void xrevive (class reader_t *pipe_);
+        int xsetsockopt (int option_, const void *optval_, size_t optvallen_);
+        int xsend (zmq_msg_t *msg_, int flags_);
+        int xflush ();
+        int xrecv (zmq_msg_t *msg_, int flags_);
+        bool xhas_in ();
+        bool xhas_out ();
+
+    private:
+
+        xrep_t (const xrep_t&);
+        void operator = (const xrep_t&);
+    };
+
+}
+
+#endif
diff --git a/src/xreq.cpp b/src/xreq.cpp
new file mode 100644
index 0000000..b404779
--- /dev/null
+++ b/src/xreq.cpp
@@ -0,0 +1,95 @@
+/*
+    Copyright (c) 2007-2009 FastMQ Inc.
+
+    This file is part of 0MQ.
+
+    0MQ is free software; you can redistribute it and/or modify it under
+    the terms of the Lesser GNU General Public License as published by
+    the Free Software Foundation; either version 3 of the License, or
+    (at your option) any later version.
+
+    0MQ is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    Lesser GNU General Public License for more details.
+
+    You should have received a copy of the Lesser GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "../bindings/c/zmq.h"
+
+#include "xreq.hpp"
+#include "err.hpp"
+#include "pipe.hpp"
+
+zmq::xreq_t::xreq_t (class app_thread_t *parent_) :
+    socket_base_t (parent_)
+{
+    options.requires_in = true;
+    options.requires_out = true;
+}
+
+zmq::xreq_t::~xreq_t ()
+{
+}
+
+void zmq::xreq_t::xattach_pipes (class reader_t *inpipe_,
+    class writer_t *outpipe_)
+{
+    zmq_assert (false);
+}
+
+void zmq::xreq_t::xdetach_inpipe (class reader_t *pipe_)
+{
+    zmq_assert (false);
+}
+
+void zmq::xreq_t::xdetach_outpipe (class writer_t *pipe_)
+{
+    zmq_assert (false);
+}
+
+void zmq::xreq_t::xkill (class reader_t *pipe_)
+{
+    zmq_assert (false);
+}
+
+void zmq::xreq_t::xrevive (class reader_t *pipe_)
+{
+    zmq_assert (false);
+}
+
+int zmq::xreq_t::xsetsockopt (int option_, const void *optval_,
+    size_t optvallen_)
+{
+    errno = EINVAL;
+    return -1;
+}
+
+int zmq::xreq_t::xsend (zmq_msg_t *msg_, int flags_)
+{
+    zmq_assert (false);
+}
+
+int zmq::xreq_t::xflush ()
+{
+    zmq_assert (false);
+}
+
+int zmq::xreq_t::xrecv (zmq_msg_t *msg_, int flags_)
+{
+    zmq_assert (false);
+}
+
+bool zmq::xreq_t::xhas_in ()
+{
+    zmq_assert (false);
+}
+
+bool zmq::xreq_t::xhas_out ()
+{
+    zmq_assert (false);
+}
+
+
diff --git a/src/xreq.hpp b/src/xreq.hpp
new file mode 100644
index 0000000..8d6a3b2
--- /dev/null
+++ b/src/xreq.hpp
@@ -0,0 +1,57 @@
+/*
+    Copyright (c) 2007-2009 FastMQ Inc.
+
+    This file is part of 0MQ.
+
+    0MQ is free software; you can redistribute it and/or modify it under
+    the terms of the Lesser GNU General Public License as published by
+    the Free Software Foundation; either version 3 of the License, or
+    (at your option) any later version.
+
+    0MQ is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    Lesser GNU General Public License for more details.
+
+    You should have received a copy of the Lesser GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef __ZMQ_XREQ_HPP_INCLUDED__
+#define __ZMQ_XREQ_HPP_INCLUDED__
+
+#include "socket_base.hpp"
+#include "yarray.hpp"
+
+namespace zmq
+{
+
+    class xreq_t : public socket_base_t
+    {
+    public:
+
+        xreq_t (class app_thread_t *parent_);
+        ~xreq_t ();
+
+        //  Overloads of functions from socket_base_t.
+        void xattach_pipes (class reader_t *inpipe_, class writer_t *outpipe_);
+        void xdetach_inpipe (class reader_t *pipe_);
+        void xdetach_outpipe (class writer_t *pipe_);
+        void xkill (class reader_t *pipe_);
+        void xrevive (class reader_t *pipe_);
+        int xsetsockopt (int option_, const void *optval_, size_t optvallen_);
+        int xsend (zmq_msg_t *msg_, int flags_);
+        int xflush ();
+        int xrecv (zmq_msg_t *msg_, int flags_);
+        bool xhas_in ();
+        bool xhas_out ();
+
+    private:
+
+        xreq_t (const xreq_t&);
+        void operator = (const xreq_t&);
+    };
+
+}
+
+#endif