1 files changed, 98 insertions, 0 deletions
diff --git a/src/GlobalEvents.cxx b/src/GlobalEvents.cxx
new file mode 100644
index 000000000..2f8569750
--- /dev/null
+++ b/src/GlobalEvents.cxx
@@ -0,0 +1,98 @@
+/*
+ * 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.
+ */
+
+#include "config.h"
+#include "GlobalEvents.hxx"
+#include "util/Manual.hxx"
+#include "event/DeferredMonitor.hxx"
+#include "gcc.h"
+
+#include <atomic>
+
+#include <assert.h>
+#include <glib.h>
+
+namespace GlobalEvents {
+	class Monitor final : public DeferredMonitor {
+	public:
+		Monitor(EventLoop &_loop):DeferredMonitor(_loop) {}
+
+	protected:
+		virtual void RunDeferred() override;
+	};
+
+	static Manual<Monitor> monitor;
+
+	static std::atomic_uint flags;
+	static Handler handlers[MAX];
+}
+
+/**
+ * Invoke the callback for a certain event.
+ */
+static void
+InvokeGlobalEvent(GlobalEvents::Event event)
+{
+	assert((unsigned)event < GlobalEvents::MAX);
+	assert(GlobalEvents::handlers[event] != NULL);
+
+	GlobalEvents::handlers[event]();
+}
+
+void
+GlobalEvents::Monitor::RunDeferred()
+{
+	const unsigned f = flags.exchange(0);
+
+	for (unsigned i = 0; i < MAX; ++i)
+		if (f & (1u << i))
+			/* invoke the event handler */
+			InvokeGlobalEvent(Event(i));
+}
+
+void
+GlobalEvents::Initialize(EventLoop &loop)
+{
+	monitor.Construct(loop);
+}
+
+void
+GlobalEvents::Deinitialize()
+{
+	monitor.Destruct();
+}
+
+void
+GlobalEvents::Register(Event event, Handler callback)
+{
+	assert((unsigned)event < MAX);
+	assert(handlers[event] == NULL);
+
+	handlers[event] = callback;
+}
+
+void
+GlobalEvents::Emit(Event event)
+{
+	assert((unsigned)event < MAX);
+
+	const unsigned mask = 1u << unsigned(event);
+	if (GlobalEvents::flags.fetch_or(mask) == 0)
+		monitor->Schedule();
+}