event/SocketMonitor: wrapper class for GSource + GPollFD

1 files changed, 118 insertions, 0 deletions

diff --git a/src/event/SocketMonitor.hxx b/src/event/SocketMonitor.hxx
new file mode 100644
index 00000000..ca3c5dcc
--- /dev/null
+++ b/src/event/SocketMonitor.hxx
@@ -0,0 +1,118 @@
+/*
+ * 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_SOCKET_MONITOR_HXX
+#define MPD_SOCKET_MONITOR_HXX
+
+#include "check.h"
+
+#include <glib.h>
+
+#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;
+
+class SocketMonitor {
+	struct Source {
+		GSource base;
+
+		SocketMonitor *monitor;
+	};
+
+	int fd;
+	EventLoop &loop;
+	Source *source;
+	GPollFD poll;
+
+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;
+
+	SocketMonitor(int _fd, EventLoop &_loop);
+
+	~SocketMonitor();
+
+	bool IsDefined() const {
+		return fd >= 0;
+	}
+
+	int Get() const {
+		assert(IsDefined());
+
+		return fd;
+	}
+
+	void Close();
+
+	void Schedule(unsigned flags) {
+		poll.events = flags;
+		poll.revents &= flags;
+	}
+
+	void Cancel() {
+		poll.events = 0;
+	}
+
+	void ScheduleRead() {
+		poll.events |= READ|HANGUP|ERROR;
+	}
+
+	void ScheduleWrite() {
+		poll.events |= WRITE;
+	}
+
+	void CancelRead() {
+		poll.events &= ~(READ|HANGUP|ERROR);
+	}
+
+	void CancelWrite() {
+		poll.events &= ~WRITE;
+	}
+
+protected:
+	virtual void OnSocketReady(unsigned flags) = 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 Check() const {
+		return (poll.revents & poll.events) != 0;
+	}
+
+	void Dispatch() {
+		OnSocketReady(poll.revents & poll.events);
+	}
+};
+
+#endif