1 files changed, 254 insertions, 0 deletions
diff --git a/src/event/MultiSocketMonitor.hxx b/src/event/MultiSocketMonitor.hxx
new file mode 100644
index 000000000..fe74206a3
--- /dev/null
+++ b/src/event/MultiSocketMonitor.hxx
@@ -0,0 +1,254 @@
+/*
+ * 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"
+
+#ifdef USE_EPOLL
+#include "IdleMonitor.hxx"
+#include "TimeoutMonitor.hxx"
+#include "SocketMonitor.hxx"
+#else
+#include "glib_compat.h"
+#include <glib.h>
+
+#endif
+
+#include <forward_list>
+
+#include <assert.h>
+#include <stdint.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
+#ifdef USE_EPOLL
+	: private IdleMonitor, private TimeoutMonitor
+#endif
+{
+#ifdef USE_EPOLL
+	class SingleFD final : public SocketMonitor {
+		MultiSocketMonitor &multi;
+
+		unsigned revents;
+
+	public:
+		SingleFD(MultiSocketMonitor &_multi, int _fd, unsigned events)
+			:SocketMonitor(_fd, _multi.GetEventLoop()),
+			multi(_multi), revents(0) {
+			Schedule(events);
+		}
+
+		int GetFD() const {
+			return SocketMonitor::Get();
+		}
+
+		unsigned GetEvents() const {
+			return SocketMonitor::GetScheduledFlags();
+		}
+
+		void SetEvents(unsigned _events) {
+			revents &= _events;
+			SocketMonitor::Schedule(_events);
+		}
+
+		unsigned GetReturnedEvents() const {
+			return revents;
+		}
+
+		void ClearReturnedEvents() {
+			revents = 0;
+		}
+
+	protected:
+		virtual bool OnSocketReady(unsigned flags) override {
+			revents = flags;
+			multi.SetReady();
+			return true;
+		}
+	};
+
+	friend class SingleFD;
+
+	bool ready, refresh;
+#else
+	struct Source {
+		GSource base;
+
+		MultiSocketMonitor *monitor;
+	};
+
+	struct SingleFD {
+		GPollFD pfd;
+
+		constexpr SingleFD(gcc_unused MultiSocketMonitor &m,
+				   int fd, unsigned events)
+			:pfd{fd, gushort(events), 0} {}
+
+		constexpr int GetFD() const {
+			return pfd.fd;
+		}
+
+		constexpr unsigned GetEvents() const {
+			return pfd.events;
+		}
+
+		constexpr unsigned GetReturnedEvents() const {
+			return pfd.revents;
+		}
+
+		void SetEvents(unsigned _events) {
+			pfd.events = _events;
+		}
+	};
+
+	EventLoop &loop;
+	Source *source;
+	uint64_t absolute_timeout_us;
+#endif
+
+	std::forward_list<SingleFD> fds;
+
+public:
+#ifdef USE_EPOLL
+	static constexpr unsigned READ = SocketMonitor::READ;
+	static constexpr unsigned WRITE = SocketMonitor::WRITE;
+	static constexpr unsigned ERROR = SocketMonitor::ERROR;
+	static constexpr unsigned HANGUP = SocketMonitor::HANGUP;
+#else
+	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;
+#endif
+
+	MultiSocketMonitor(EventLoop &_loop);
+	~MultiSocketMonitor();
+
+#ifdef USE_EPOLL
+	using IdleMonitor::GetEventLoop;
+#else
+	EventLoop &GetEventLoop() {
+		return loop;
+	}
+#endif
+
+public:
+#ifndef USE_EPOLL
+	gcc_pure
+	uint64_t GetTime() const {
+		return g_source_get_time(&source->base);
+	}
+#endif
+
+	void InvalidateSockets() {
+#ifdef USE_EPOLL
+		refresh = true;
+		IdleMonitor::Schedule();
+#else
+		/* no-op because GLib always calls the GSource's
+		   "prepare" method before each poll() anyway */
+#endif
+	}
+
+	void AddSocket(int fd, unsigned events) {
+		fds.emplace_front(*this, fd, events);
+#ifndef USE_EPOLL
+		g_source_add_poll(&source->base, &fds.front().pfd);
+#endif
+	}
+
+	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->GetEvents() != 0);
+
+			unsigned events = e(i->GetFD());
+			if (events != 0) {
+				i->SetEvents(events);
+				prev = i;
+			} else {
+#ifdef USE_EPOLL
+				i->Steal();
+#else
+				g_source_remove_poll(&source->base, &i->pfd);
+#endif
+				fds.erase_after(prev);
+			}
+		}
+	}
+
+protected:
+	/**
+	 * @return timeout [ms] or -1 for no timeout
+	 */
+	virtual int PrepareSockets() = 0;
+	virtual void DispatchSockets() = 0;
+
+#ifdef USE_EPOLL
+private:
+	void SetReady() {
+		ready = true;
+		IdleMonitor::Schedule();
+	}
+
+	void Prepare();
+
+	virtual void OnTimeout() final {
+		SetReady();
+		IdleMonitor::Schedule();
+	}
+
+	virtual void OnIdle() final;
+
+#else
+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);
+	bool Check() const;
+
+	void Dispatch() {
+		DispatchSockets();
+	}
+#endif
+};
+
+#endif