odbus: import dbus-1 OO wrapper library

From a7cef404c1

To be used by upcoming code.

src/lib/dbus/Watch.hxx

@@ -0,0 +1,157 @@
+/*
+ * Copyright 2007-2018 Content Management AG
+ * All rights reserved.
+ *
+ * author: Max Kellermann <mk@cm4all.com>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
+ * FOUNDATION OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef ODBUS_WATCH_HXX
+#define ODBUS_WATCH_HXX
+
+#include "Connection.hxx"
+#include "event/SocketMonitor.hxx"
+#include "event/DeferEvent.hxx"
+#include "Compiler.h"
+
+#include <dbus/dbus.h>
+
+#include <map>
+
+class EventLoop;
+
+namespace ODBus {
+
+class WatchManagerObserver {
+public:
+	virtual void OnDBusClosed() noexcept = 0;
+};
+
+/**
+ * Integrate a DBusConnection into the #EventLoop.
+ */
+class WatchManager {
+	WatchManagerObserver &observer;
+
+	Connection connection;
+
+	class Watch final : SocketMonitor {
+		WatchManager &parent;
+		DBusWatch &watch;
+
+	public:
+		Watch(EventLoop &event_loop, WatchManager &_parent,
+		      DBusWatch &_watch) noexcept;
+
+		void Toggled() noexcept;
+
+	private:
+		bool OnSocketReady(unsigned flags) noexcept override;
+	};
+
+	std::map<DBusWatch *, Watch> watches;
+
+	DeferEvent defer_dispatch;
+
+public:
+	WatchManager(EventLoop &event_loop,
+		     WatchManagerObserver &_observer) noexcept
+		:observer(_observer),
+		 defer_dispatch(event_loop, BIND_THIS_METHOD(Dispatch))
+	{
+	}
+
+	template<typename C>
+	WatchManager(EventLoop &event_loop, WatchManagerObserver &_observer,
+		     C &&_connection) noexcept
+		:WatchManager(event_loop, _observer)
+	{
+		SetConnection(std::forward<C>(_connection));
+	}
+
+	~WatchManager() noexcept {
+		Shutdown();
+	}
+
+	WatchManager(const WatchManager &) = delete;
+	WatchManager &operator=(const WatchManager &) = delete;
+
+	void Shutdown() noexcept;
+
+	EventLoop &GetEventLoop() noexcept {
+		return defer_dispatch.GetEventLoop();
+	}
+
+	Connection &GetConnection() noexcept {
+		return connection;
+	}
+
+	template<typename C>
+	void SetConnection(C &&_connection) noexcept {
+		Shutdown();
+
+		connection = std::forward<C>(_connection);
+
+		if (connection)
+			dbus_connection_set_watch_functions(connection,
+							    AddFunction,
+							    RemoveFunction,
+							    ToggledFunction,
+							    (void *)this,
+							    nullptr);
+	}
+
+private:
+	void ScheduleDispatch() noexcept {
+		defer_dispatch.Schedule();
+	}
+
+	void Dispatch() noexcept;
+
+	bool Add(DBusWatch *watch) noexcept;
+	void Remove(DBusWatch *watch) noexcept;
+	void Toggled(DBusWatch *watch) noexcept;
+
+	static dbus_bool_t AddFunction(DBusWatch *watch, void *data) noexcept {
+		auto &wm = *(WatchManager *)data;
+		return wm.Add(watch);
+	}
+
+	static void RemoveFunction(DBusWatch *watch, void *data) noexcept {
+		auto &wm = *(WatchManager *)data;
+		wm.Remove(watch);
+	}
+
+	static void ToggledFunction(DBusWatch *watch, void *data) noexcept {
+		auto &wm = *(WatchManager *)data;
+		wm.Toggled(watch);
+	}
+};
+
+} /* namespace ODBus */
+
+#endif