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+/*
+ 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 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 "platform.hpp"
+
+#include <string.h>
+#include <algorithm>
+
+#ifdef ZMQ_HAVE_WINDOWS
+#include "winsock2.h"
+#elif defined ZMQ_HAVE_HPUX
+#include <sys/param.h>
+#include <sys/types.h>
+#include <sys/time.h>
+#elif defined ZMQ_HAVE_OPENVMS
+#include <sys/types.h>
+#include <sys/time.h>
+#else
+#include <sys/select.h>
+#endif
+
+#include "select.hpp"
+#include "err.hpp"
+#include "config.hpp"
+#include "i_poll_events.hpp"
+
+zmq::select_t::select_t () :
+ maxfd (retired_fd),
+ retired (false),
+ stopping (false)
+{
+ // Clear file descriptor sets.
+ FD_ZERO (&source_set_in);
+ FD_ZERO (&source_set_out);
+ FD_ZERO (&source_set_err);
+}
+
+zmq::select_t::~select_t ()
+{
+ worker.stop ();
+
+ // Make sure there are no fds registered on shutdown.
+ zmq_assert (load.get () == 0);
+}
+
+zmq::select_t::handle_t zmq::select_t::add_fd (fd_t fd_, i_poll_events *events_)
+{
+ // Store the file descriptor.
+ fd_entry_t entry = {fd_, events_};
+ fds.push_back (entry);
+
+ // Start polling on errors.
+ FD_SET (fd_, &source_set_err);
+
+ // Adjust maxfd if necessary.
+ if (fd_ > maxfd)
+ maxfd = fd_;
+
+ // Increase the load metric of the thread.
+ load.add (1);
+
+ return fd_;
+}
+
+void zmq::select_t::rm_fd (handle_t handle_)
+{
+ // Mark the descriptor as retired.
+ fd_set_t::iterator it;
+ for (it = fds.begin (); it != fds.end (); it ++)
+ if (it->fd == handle_)
+ break;
+ zmq_assert (it != fds.end ());
+ it->fd = retired_fd;
+ retired = true;
+
+ // Stop polling on the descriptor.
+ FD_CLR (handle_, &source_set_in);
+ FD_CLR (handle_, &source_set_out);
+ FD_CLR (handle_, &source_set_err);
+
+ // Discard all events generated on this file descriptor.
+ FD_CLR (handle_, &readfds);
+ FD_CLR (handle_, &writefds);
+ FD_CLR (handle_, &exceptfds);
+
+ // Adjust the maxfd attribute if we have removed the
+ // highest-numbered file descriptor.
+ if (handle_ == maxfd) {
+ maxfd = retired_fd;
+ for (fd_set_t::iterator it = fds.begin (); it != fds.end (); it ++)
+ if (it->fd > maxfd)
+ maxfd = it->fd;
+ }
+
+ // Decrease the load metric of the thread.
+ load.sub (1);
+}
+
+void zmq::select_t::set_pollin (handle_t handle_)
+{
+ FD_SET (handle_, &source_set_in);
+}
+
+void zmq::select_t::reset_pollin (handle_t handle_)
+{
+ FD_CLR (handle_, &source_set_in);
+}
+
+void zmq::select_t::set_pollout (handle_t handle_)
+{
+ FD_SET (handle_, &source_set_out);
+}
+
+void zmq::select_t::reset_pollout (handle_t handle_)
+{
+ FD_CLR (handle_, &source_set_out);
+}
+
+void zmq::select_t::add_timer (i_poll_events *events_)
+{
+ timers.push_back (events_);
+}
+
+void zmq::select_t::cancel_timer (i_poll_events *events_)
+{
+ timers_t::iterator it = std::find (timers.begin (), timers.end (), events_);
+ if (it != timers.end ())
+ timers.erase (it);
+}
+
+int zmq::select_t::get_load ()
+{
+ return load.get ();
+}
+
+void zmq::select_t::start ()
+{
+ worker.start (worker_routine, this);
+}
+
+void zmq::select_t::stop ()
+{
+ stopping = true;
+}
+
+void zmq::select_t::loop ()
+{
+ while (!stopping) {
+
+ // Intialise the pollsets.
+ memcpy (&readfds, &source_set_in, sizeof source_set_in);
+ memcpy (&writefds, &source_set_out, sizeof source_set_out);
+ memcpy (&exceptfds, &source_set_err, sizeof source_set_err);
+
+ // Compute the timout interval. Select is free to overwrite the
+ // value so we have to compute it each time anew.
+ timeval timeout = {max_timer_period / 1000,
+ (max_timer_period % 1000) * 1000};
+
+ // Wait for events.
+ int rc = select (maxfd + 1, &readfds, &writefds, &exceptfds,
+ timers.empty () ? NULL : &timeout);
+
+#ifdef ZMQ_HAVE_WINDOWS
+ wsa_assert (rc != SOCKET_ERROR);
+#else
+ if (rc == -1 && errno == EINTR)
+ continue;
+ errno_assert (rc != -1);
+#endif
+
+ // Handle timer.
+ if (!rc) {
+
+ // Use local list of timers as timer handlers may fill new timers
+ // into the original array.
+ timers_t t;
+ std::swap (timers, t);
+
+ // Trigger all the timers.
+ for (timers_t::iterator it = t.begin (); it != t.end (); it ++)
+ (*it)->timer_event ();
+
+ continue;
+ }
+
+ for (fd_set_t::size_type i = 0; i < fds.size (); i ++) {
+ if (fds [i].fd == retired_fd)
+ continue;
+ if (FD_ISSET (fds [i].fd, &exceptfds))
+ fds [i].events->in_event ();
+ if (fds [i].fd == retired_fd)
+ continue;
+ if (FD_ISSET (fds [i].fd, &writefds))
+ fds [i].events->out_event ();
+ if (fds [i].fd == retired_fd)
+ continue;
+ if (FD_ISSET (fds [i].fd, &readfds))
+ fds [i].events->in_event ();
+ }
+
+ // Destroy retired event sources.
+ if (retired) {
+ for (fd_set_t::size_type i = 0; i < fds.size (); i ++) {
+ if (fds [i].fd == retired_fd) {
+ fds.erase (fds.begin () + i);
+ i --;
+ }
+ }
+ retired = false;
+ }
+ }
+}
+
+void zmq::select_t::worker_routine (void *arg_)
+{
+ ((select_t*) arg_)->loop ();
+}