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Diffstat (limited to 'src/event/MultiSocketMonitor.hxx')
-rw-r--r-- | src/event/MultiSocketMonitor.hxx | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/src/event/MultiSocketMonitor.hxx b/src/event/MultiSocketMonitor.hxx new file mode 100644 index 000000000..9d0e1502b --- /dev/null +++ b/src/event/MultiSocketMonitor.hxx @@ -0,0 +1,124 @@ +/* + * Copyright (C) 2003-2013 The Music Player Daemon Project + * http://www.musicpd.org + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program 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 General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#ifndef MPD_MULTI_SOCKET_MONITOR_HXX +#define MPD_MULTI_SOCKET_MONITOR_HXX + +#include "check.h" +#include "gcc.h" + +#include <glib.h> + +#include <forward_list> + +#include <assert.h> + +#ifdef WIN32 +/* ERRORis a WIN32 macro that poisons our namespace; this is a + kludge to allow us to use it anyway */ +#ifdef ERROR +#undef ERROR +#endif +#endif + +class EventLoop; + +/** + * Monitor multiple sockets. + */ +class MultiSocketMonitor { + struct Source { + GSource base; + + MultiSocketMonitor *monitor; + }; + + EventLoop &loop; + Source *source; + std::forward_list<GPollFD> fds; + +public: + static constexpr unsigned READ = G_IO_IN; + static constexpr unsigned WRITE = G_IO_OUT; + static constexpr unsigned ERROR = G_IO_ERR; + static constexpr unsigned HANGUP = G_IO_HUP; + + MultiSocketMonitor(EventLoop &_loop); + ~MultiSocketMonitor(); + +public: + gcc_pure + gint64 GetTime() const { + return g_source_get_time(&source->base); + } + + void InvalidateSockets() { + /* no-op because GLib always calls the GSource's + "prepare" method before each poll() anyway */ + } + + void AddSocket(int fd, unsigned events) { + fds.push_front({fd, gushort(events), 0}); + g_source_add_poll(&source->base, &fds.front()); + } + + template<typename E> + void UpdateSocketList(E &&e) { + for (auto prev = fds.before_begin(), end = fds.end(), + i = std::next(prev); + i != end; i = std::next(prev)) { + assert(i->events != 0); + + unsigned events = e(i->fd); + if (events != 0) { + i->events = events; + prev = i; + } else { + g_source_remove_poll(&source->base, &*i); + fds.erase_after(prev); + } + } + } + +protected: + virtual void PrepareSockets(gcc_unused gint *timeout_r) {} + virtual bool CheckSockets() const { return false; } + virtual void DispatchSockets() = 0; + +public: + /* GSource callbacks */ + static gboolean Prepare(GSource *source, gint *timeout_r); + static gboolean Check(GSource *source); + static gboolean Dispatch(GSource *source, GSourceFunc callback, + gpointer user_data); + +private: + bool Prepare(gint *timeout_r) { + PrepareSockets(timeout_r); + return false; + } + + bool Check() const; + + void Dispatch() { + DispatchSockets(); + } +}; + +#endif |