add pollset poller in AIX

add a new poller named pollset which will get benefit of performance in AIX platform.

pollset.hpp

@@ -0,0 +1,121 @@
+/*
+    Copyright (c) 2007-2016 Contributors as noted in the AUTHORS file
+
+    This file is part of libzmq, the ZeroMQ core engine in C++.
+
+    libzmq is free software; you can redistribute it and/or modify it under
+    the terms of the GNU Lesser General Public License (LGPL) as published
+    by the Free Software Foundation; either version 3 of the License, or
+    (at your option) any later version.
+
+    As a special exception, the Contributors give you permission to link
+    this library with independent modules to produce an executable,
+    regardless of the license terms of these independent modules, and to
+    copy and distribute the resulting executable under terms of your choice,
+    provided that you also meet, for each linked independent module, the
+    terms and conditions of the license of that module. An independent
+    module is a module which is not derived from or based on this library.
+    If you modify this library, you must extend this exception to your
+    version of the library.
+
+    libzmq 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 GNU Lesser General Public
+    License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef __ZMQ_POLLSET_HPP_INCLUDED__
+#define __ZMQ_POLLSET_HPP_INCLUDED__
+
+//  poller.hpp decides which polling mechanism to use.
+#include "poller.hpp"
+#if defined ZMQ_USE_POLLSET
+
+#include <sys/poll.h>
+#include <sys/pollset.h>
+#include <vector>
+
+#include "ctx.hpp"
+#include "fd.hpp"
+#include "thread.hpp"
+#include "poller_base.hpp"
+
+namespace zmq
+{
+
+    struct i_poll_events;
+
+    //  This class implements socket polling mechanism using the AIX-specific
+    //  pollset mechanism.
+
+    class pollset_t : public poller_base_t
+    {
+    public:
+
+        typedef void* handle_t;
+
+        pollset_t (const ctx_t &ctx_);
+        ~pollset_t ();
+
+        //  "poller" concept.
+        handle_t add_fd (fd_t fd_, zmq::i_poll_events *events_);
+        void rm_fd (handle_t handle_);
+        void set_pollin (handle_t handle_);
+        void reset_pollin (handle_t handle_);
+        void set_pollout (handle_t handle_);
+        void reset_pollout (handle_t handle_);
+        void start ();
+        void stop ();
+
+        static int max_fds ();
+
+    private:
+
+        //  Main worker thread routine.
+        static void worker_routine (void *arg_);
+
+        //  Main event loop.
+        void loop ();
+
+        // Reference to ZMQ context.
+        const ctx_t &ctx;
+
+        //  Main pollset file descriptor
+        ::pollset_t pollset_fd;
+
+        struct poll_entry_t
+        {
+            fd_t                fd;
+            bool                flag_pollin;
+            bool                flag_pollout;
+            zmq::i_poll_events *events;
+        };
+
+        //  List of retired event sources.
+        typedef std::vector <poll_entry_t*> retired_t;
+        retired_t retired;
+
+        //  This table stores data for registered descriptors.
+        typedef std::vector <poll_entry_t*> fd_table_t;
+        fd_table_t fd_table;
+
+        //  If true, thread is in the process of shutting down.
+        bool stopping;
+
+        //  Handle of the physical thread doing the I/O work.
+        thread_t worker;
+
+        pollset_t (const pollset_t&);
+        const pollset_t &operator = (const pollset_t&);
+    };
+
+    typedef pollset_t poller_t;
+
+}
+
+#endif
+
+#endif