event/TimeoutMonitor: wrapper for g_timeout_source_new()

Makefile.am

@@ -354,6 +354,7 @@ libutil_a_SOURCES = \
 
 libevent_a_SOURCES = \
 	src/event/WakeFD.cxx src/event/WakeFD.hxx \
+	src/event/TimeoutMonitor.hxx src/event/TimeoutMonitor.cxx \
 	src/event/Loop.hxx
 
 # PCM library

src/InotifyQueue.cxx

@@ -20,7 +20,6 @@
 #include "config.h"
 #include "InotifyQueue.hxx"
 #include "UpdateGlue.hxx"
-#include "Main.hxx"
 #include "event/Loop.hxx"
 
 #include <glib.h>
@@ -39,14 +38,8 @@ enum {
 	INOTIFY_UPDATE_DELAY_S = 5,
 };
 
-InotifyQueue::~InotifyQueue()
-{
-	if (source_id != 0)
-		g_source_remove(source_id);
-}
-
-inline bool
-InotifyQueue::Run()
+bool
+InotifyQueue::OnTimeout()
 {
 	unsigned id;
 
@@ -64,17 +57,9 @@ InotifyQueue::Run()
 	}
 
 	/* done, remove the timer event by returning false */
-	source_id = 0;
 	return false;
 }
 
-gboolean
-InotifyQueue::Run(gpointer data)
-{
-	InotifyQueue &queue = *(InotifyQueue *)data;
-	return queue.Run();
-}
-
 static bool
 path_in(const char *path, const char *possible_parent)
 {
@@ -88,10 +73,7 @@ path_in(const char *path, const char *possible_parent)
 void
 InotifyQueue::Enqueue(const char *uri_utf8)
 {
-	if (source_id != 0)
-		g_source_remove(source_id);
-	source_id = main_loop->AddTimeoutSeconds(INOTIFY_UPDATE_DELAY_S,
-						 Run, nullptr);
+	ScheduleSeconds(INOTIFY_UPDATE_DELAY_S);
 
 	for (auto i = queue.begin(), end = queue.end(); i != end;) {
 		const char *current_uri = i->c_str();

src/InotifyQueue.hxx

@@ -20,23 +20,22 @@
 #ifndef MPD_INOTIFY_QUEUE_HXX
 #define MPD_INOTIFY_QUEUE_HXX
 
-#include <glib.h>
+#include "event/TimeoutMonitor.hxx"
+#include "gcc.h"
 
 #include <list>
 #include <string>
 
-class InotifyQueue {
+class InotifyQueue final : private TimeoutMonitor {
 	std::list<std::string> queue;
-	guint source_id;
 
 public:
-	~InotifyQueue();
+	InotifyQueue(EventLoop &_loop):TimeoutMonitor(_loop) {}
 
 	void Enqueue(const char *uri_utf8);
 
 private:
-	bool Run();
-	static gboolean Run(gpointer ctx);
+	virtual bool OnTimeout() override;
 };
 
 #endif

src/InotifyUpdate.cxx

@@ -22,6 +22,7 @@
 #include "InotifySource.hxx"
 #include "InotifyQueue.hxx"
 #include "Mapper.hxx"
+#include "Main.hxx"
 
 extern "C" {
 #include "path.h"
@@ -342,7 +343,7 @@ mpd_inotify_init(unsigned max_depth)
 
 	recursive_watch_subdirectories(&inotify_root, path, 0);
 
-	inotify_queue = new InotifyQueue();
+	inotify_queue = new InotifyQueue(*main_loop);
 
 	g_debug("watching music directory");
 }

src/StateFile.cxx

@@ -35,17 +35,11 @@
 #define G_LOG_DOMAIN "state_file"
 
 StateFile::StateFile(const char *_path, Partition &_partition, EventLoop &_loop)
-	:path(_path), partition(_partition), loop(_loop),
-	 source_id(0),
+	:TimeoutMonitor(_loop), path(_path), partition(_partition),
 	 prev_volume_version(0), prev_output_version(0),
 	 prev_playlist_version(0)
 {
-	source_id = loop.AddTimeoutSeconds(5 * 60, TimerCallback, this);
-}
-
-StateFile::~StateFile()
-{
-	g_source_remove(source_id);
+	ScheduleSeconds(5 * 60);
 }
 
 void
@@ -120,11 +114,9 @@ StateFile::AutoWrite()
  * This function is called every 5 minutes by the GLib main loop, and
  * saves the state file.
  */
-gboolean
-StateFile::TimerCallback(gpointer data)
+bool
+StateFile::OnTimeout()
 {
-	StateFile &state_file = *(StateFile *)data;
-
-	state_file.AutoWrite();
+	AutoWrite();
 	return true;
 }

src/StateFile.hxx

@@ -20,21 +20,17 @@
 #ifndef MPD_STATE_FILE_HXX
 #define MPD_STATE_FILE_HXX
 
-#include <glib.h>
+#include "event/TimeoutMonitor.hxx"
+#include "gcc.h"
 
 #include <string>
 
 struct Partition;
-class EventLoop;
 
-class StateFile {
+class StateFile final : private TimeoutMonitor {
 	std::string path;
 
 	Partition &partition;
-	EventLoop &loop;
-
-	/** the GLib source id for the save timer */
-	guint source_id;
 
 	/**
 	 * These version numbers determine whether we need to save the state
@@ -45,14 +41,13 @@ class StateFile {
 
 public:
 	StateFile(const char *path, Partition &partition, EventLoop &loop);
-	~StateFile();
 
 	void Read();
 	void Write();
 	void AutoWrite();
 
 private:
-	static gboolean TimerCallback(gpointer data);
+	virtual bool OnTimeout() override;
 };
 
 #endif /* STATE_FILE_H */

src/event/Loop.hxx

@@ -64,22 +64,20 @@ public:
 		return id;
 	}
 
-	guint AddTimeout(guint interval_ms,
-			 GSourceFunc function, gpointer data) {
+	GSource *AddTimeout(guint interval_ms,
+			    GSourceFunc function, gpointer data) {
 		GSource *source = g_timeout_source_new(interval_ms);
 		g_source_set_callback(source, function, data, nullptr);
-		guint id = g_source_attach(source, GetContext());
-		g_source_unref(source);
-		return id;
+		g_source_attach(source, GetContext());
+		return source;
 	}
 
-	guint AddTimeoutSeconds(guint interval_s,
-				GSourceFunc function, gpointer data) {
+	GSource *AddTimeoutSeconds(guint interval_s,
+				   GSourceFunc function, gpointer data) {
 		GSource *source = g_timeout_source_new_seconds(interval_s);
 		g_source_set_callback(source, function, data, nullptr);
-		guint id = g_source_attach(source, GetContext());
-		g_source_unref(source);
-		return id;
+		g_source_attach(source, GetContext());
+		return source;
 	}
 };
 

src/event/TimeoutMonitor.cxx

+/*
+ * 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 "TimeoutMonitor.hxx"
+#include "Loop.hxx"
+
+void
+TimeoutMonitor::Cancel()
+{
+	if (source != nullptr) {
+		g_source_destroy(source);
+		g_source_unref(source);
+		source = nullptr;
+	}
+}
+
+void
+TimeoutMonitor::Schedule(unsigned ms)
+{
+	Cancel();
+	source = loop.AddTimeout(ms, Callback, this);
+}
+
+void
+TimeoutMonitor::ScheduleSeconds(unsigned s)
+{
+	Cancel();
+	source = loop.AddTimeoutSeconds(s, Callback, this);
+}
+
+bool
+TimeoutMonitor::Run()
+{
+	bool result = OnTimeout();
+	if (!result && source != nullptr) {
+		g_source_unref(source);
+		source = nullptr;
+	}
+
+	return result;
+}
+
+gboolean
+TimeoutMonitor::Callback(gpointer data)
+{
+	TimeoutMonitor &monitor = *(TimeoutMonitor *)data;
+	return monitor.Run();
+}

src/event/TimeoutMonitor.hxx

+/*
+ * 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_TIMEOUT_MONITOR_HXX
+#define MPD_SOCKET_TIMEOUT_MONITOR_HXX
+
+#include "check.h"
+
+#include <glib.h>
+
+class EventLoop;
+
+class TimeoutMonitor {
+	EventLoop &loop;
+	GSource *source;
+
+public:
+	TimeoutMonitor(EventLoop &_loop)
+		:loop(_loop), source(nullptr) {}
+
+	~TimeoutMonitor() {
+		Cancel();
+	}
+
+	bool IsActive() const {
+		return source != nullptr;
+	}
+
+	void Schedule(unsigned ms);
+	void ScheduleSeconds(unsigned s);
+	void Cancel();
+
+protected:
+	/**
+	 * @return true reschedules the timeout again
+	 */
+	virtual bool OnTimeout() = 0;
+
+private:
+	bool Run();
+	static gboolean Callback(gpointer data);
+};
+
+#endif /* MAIN_NOTIFY_H */