libzmq/src/reaper.cpp

/*
    Copyright (c) 2007-2010 iMatix Corporation

    This file is part of 0MQ.

    0MQ is free software; you can redistribute it and/or modify it under
    the terms of the GNU Lesser 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
    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/>.
*/

#include "reaper.hpp"
#include "socket_base.hpp"
#include "err.hpp"

zmq::reaper_t::reaper_t (class ctx_t *ctx_, uint32_t tid_) :
    object_t (ctx_, tid_),
    terminating (false),
    has_timer (false)
{
    poller = new (std::nothrow) poller_t;
    zmq_assert (poller);

    mailbox_handle = poller->add_fd (mailbox.get_fd (), this);
    poller->set_pollin (mailbox_handle);
}

zmq::reaper_t::~reaper_t ()
{
    delete poller;
}

zmq::mailbox_t *zmq::reaper_t::get_mailbox ()
{
    return &mailbox;
}

void zmq::reaper_t::start ()
{
    //  Start the thread.
    poller->start ();
}

void zmq::reaper_t::stop ()
{
    send_stop ();
}

void zmq::reaper_t::in_event ()
{
    while (true) {

        //  Get the next command. If there is none, exit.
        command_t cmd;
        int rc = mailbox.recv (&cmd, false);
        if (rc != 0 && errno == EINTR)
            continue;
        if (rc != 0 && errno == EAGAIN)
            break;
        errno_assert (rc == 0);

        //  Process the command.
        cmd.destination->process_command (cmd);
    }
}

void zmq::reaper_t::out_event ()
{
    //  We are never polling for POLLOUT here. This function is never called.
    zmq_assert (false);
}

void zmq::reaper_t::timer_event (int id_)
{
    zmq_assert (has_timer);
    has_timer = false;
    reap ();
}

void zmq::reaper_t::reap ()
{
    //  Try to reap each socket in the list.
    for (sockets_t::iterator it = sockets.begin (); it != sockets.end ();) {
        if ((*it)->reap ()) {

            //  MSVC version of STL requires this to be done a spacial way...
#if defined _MSC_VER
            it = sockets.erase (it);
#else
            sockets.erase (it);
#endif
        }
        else
            ++it;
    }

    //  If there are still sockets to reap, wait a while, then try again.
    if (!sockets.empty () && !has_timer) {
        poller->add_timer (1 , this, 0);
        has_timer = true;
        return;
    }

    //  No more sockets and the context is already shutting down.
    if (terminating) {
        send_done ();
        poller->rm_fd (mailbox_handle);
        poller->stop ();
        return;
    }
}

void zmq::reaper_t::process_stop ()
{
    terminating = true;

    if (sockets.empty ()) {
        send_done ();
        poller->rm_fd (mailbox_handle);
        poller->stop ();
    }
}

void zmq::reaper_t::process_reap (socket_base_t *socket_)
{
    //  Start termination of associated I/O object hierarchy.
    socket_->terminate ();
    sockets.push_back (socket_);
    reap ();
}