From f0d3b47ad819eadf04569d6886b7aa7d06154511 Mon Sep 17 00:00:00 2001
From: Max Kellermann <max@duempel.org>
Date: Sat, 4 Jan 2014 19:31:23 +0100
Subject: [PATCH] event/Loop: remove the GLib implementation

Now that the remaining known bugs in poll() implementation are fixed,
we can go on without the GLib implementation.
---
 configure.ac                     |  77 ++++++----------------
 src/event/DeferredMonitor.cxx    |  35 ----------
 src/event/DeferredMonitor.hxx    |  23 -------
 src/event/IdleMonitor.cxx        |  29 --------
 src/event/IdleMonitor.hxx        |  28 --------
 src/event/Loop.cxx               |  48 --------------
 src/event/Loop.hxx               |  62 +-----------------
 src/event/MultiSocketMonitor.cxx | 101 ----------------------------
 src/event/MultiSocketMonitor.hxx | 109 +------------------------------
 src/event/SocketMonitor.cxx      |  97 ---------------------------
 src/event/SocketMonitor.hxx      |  69 -------------------
 src/event/TimeoutMonitor.cxx     |  37 +----------
 src/event/TimeoutMonitor.hxx     |  29 --------
 13 files changed, 22 insertions(+), 722 deletions(-)

diff --git a/configure.ac b/configure.ac
index eb63735ce..58cd5af06 100644
--- a/configure.ac
+++ b/configure.ac
@@ -188,70 +188,38 @@ if test x$host_is_linux = xyes; then
 	MPD_OPTIONAL_FUNC_NODEF(epoll, epoll_create1)
 fi
 
-AC_ARG_WITH(eventloop,
-	AS_HELP_STRING(
-		[--with-eventloop=@<:@glib|internal|auto@:>@],
-		[specify event loop implementation (default=auto)]),,
-	[with_eventloop=auto])
-
 AC_ARG_WITH(pollmethod,
 	AS_HELP_STRING(
 		[--with-pollmethod=@<:@epoll|poll|winselect|auto@:>@],
 		[specify poll method for internal event loop (default=auto)]),,
 	[with_pollmethod=auto])
 
-if test "x$with_eventloop" = xauto; then
-	if
-		test "x$enable_epoll" = xyes ||
-		test "x$host_is_windows" = xyes; then
-			with_eventloop=internal
+if test "x$with_pollmethod" = xauto; then
+	if test "x$enable_epoll" = xyes; then
+		with_pollmethod=epoll
+	elif test "x$enable_poll" = xyes; then
+		with_pollmethod=poll
+	elif test "x$host_is_windows" = xyes; then
+		with_pollmethod=winselect
 	else
-		with_eventloop=glib
+		AC_MSG_ERROR([no poll method is available for your platform])
 	fi
 fi
-
-case "$with_eventloop" in
-glib)
-	AC_DEFINE(USE_GLIB_EVENTLOOP, 1,
-		[Define to use GLib event loop])
+case "$with_pollmethod" in
+epoll)
+	AC_DEFINE(USE_EPOLL, 1, [Define to poll sockets with epoll])
 	;;
-internal)
-	AC_DEFINE(USE_INTERNAL_EVENTLOOP, 1,
-		[Define to use internal event loop])
+poll)
+	AC_DEFINE(USE_POLL, 1, [Define to poll sockets with poll])
+	;;
+winselect)
+	AC_DEFINE(USE_WINSELECT, 1,
+		[Define to poll sockets with Windows select])
 	;;
 *)
-	AC_MSG_ERROR([unknown eventloop option: $with_eventloop])
-	;;
+	AC_MSG_ERROR([unknown pollmethod option: $with_pollmethod])
 esac
 
-if test "x$with_eventloop" = xinternal; then
-	if test "x$with_pollmethod" = xauto; then
-		if test "x$enable_epoll" = xyes; then
-			with_pollmethod=epoll
-		elif test "x$enable_poll" = xyes; then
-			with_pollmethod=poll
-		elif test "x$host_is_windows" = xyes; then
-			with_pollmethod=winselect
-		else
-			AC_MSG_ERROR([no poll method is available for your platform])
-		fi
-	fi
-	case "$with_pollmethod" in
-	epoll)
-		AC_DEFINE(USE_EPOLL, 1, [Define to poll sockets with epoll])
-		;;
-	poll)
-		AC_DEFINE(USE_POLL, 1, [Define to poll sockets with poll])
-		;;
-	winselect)
-		AC_DEFINE(USE_WINSELECT, 1,
-			[Define to poll sockets with Windows select])
-		;;
-	*)
-		AC_MSG_ERROR([unknown pollmethod option: $with_pollmethod])
-	esac
-fi
-
 dnl ---------------------------------------------------------------------------
 dnl Allow tools to be specifically built
 dnl ---------------------------------------------------------------------------
@@ -1728,14 +1696,7 @@ printf '\n\t'
 results(mms,[MMS])
 
 printf '\nEvent loop:\n\t'
-case $with_eventloop in
-glib)
-	printf 'GLib'
-	;;
-internal)
-	printf 'Internal (%s)' $with_pollmethod
-	;;
-esac
+printf $with_pollmethod
 
 printf '\n\n##########################################\n\n'
 
diff --git a/src/event/DeferredMonitor.cxx b/src/event/DeferredMonitor.cxx
index 5f295946e..ef7a98911 100644
--- a/src/event/DeferredMonitor.cxx
+++ b/src/event/DeferredMonitor.cxx
@@ -24,46 +24,11 @@
 void
 DeferredMonitor::Cancel()
 {
-#ifdef USE_INTERNAL_EVENTLOOP
 	loop.RemoveDeferred(*this);
-#endif
-#ifdef USE_GLIB_EVENTLOOP
-	const auto id = source_id.exchange(0);
-	if (id != 0)
-		g_source_remove(id);
-#endif
 }
 
 void
 DeferredMonitor::Schedule()
 {
-#ifdef USE_INTERNAL_EVENTLOOP
 	loop.AddDeferred(*this);
-#endif
-#ifdef USE_GLIB_EVENTLOOP
-	const unsigned id = loop.AddIdle(Callback, this);
-	const auto old_id = source_id.exchange(id);
-	if (old_id != 0)
-		g_source_remove(old_id);
-#endif
 }
-
-#ifdef USE_GLIB_EVENTLOOP
-
-void
-DeferredMonitor::Run()
-{
-	const auto id = source_id.exchange(0);
-	if (id != 0)
-		RunDeferred();
-}
-
-gboolean
-DeferredMonitor::Callback(gpointer data)
-{
-	DeferredMonitor &monitor = *(DeferredMonitor *)data;
-	monitor.Run();
-	return false;
-}
-
-#endif
diff --git a/src/event/DeferredMonitor.hxx b/src/event/DeferredMonitor.hxx
index b319d25eb..293fc5ea2 100644
--- a/src/event/DeferredMonitor.hxx
+++ b/src/event/DeferredMonitor.hxx
@@ -23,10 +23,6 @@
 #include "check.h"
 #include "Compiler.h"
 
-#ifdef USE_GLIB_EVENTLOOP
-#include <glib.h>
-#endif
-
 #include <atomic>
 
 class EventLoop;
@@ -39,25 +35,12 @@ class EventLoop;
 class DeferredMonitor {
 	EventLoop &loop;
 
-#ifdef USE_INTERNAL_EVENTLOOP
 	friend class EventLoop;
 	bool pending;
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-	std::atomic<guint> source_id;
-#endif
 
 public:
-#ifdef USE_INTERNAL_EVENTLOOP
 	DeferredMonitor(EventLoop &_loop)
 		:loop(_loop), pending(false) {}
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-	DeferredMonitor(EventLoop &_loop)
-		:loop(_loop), source_id(0) {}
-#endif
 
 	~DeferredMonitor() {
 		Cancel();
@@ -72,12 +55,6 @@ public:
 
 protected:
 	virtual void RunDeferred() = 0;
-
-private:
-#ifdef USE_GLIB_EVENTLOOP
-	void Run();
-	static gboolean Callback(gpointer data);
-#endif
 };
 
 #endif /* MAIN_NOTIFY_H */
diff --git a/src/event/IdleMonitor.cxx b/src/event/IdleMonitor.cxx
index 45f533e3f..6e500aa7b 100644
--- a/src/event/IdleMonitor.cxx
+++ b/src/event/IdleMonitor.cxx
@@ -31,14 +31,8 @@ IdleMonitor::Cancel()
 	if (!IsActive())
 		return;
 
-#ifdef USE_INTERNAL_EVENTLOOP
 	active = false;
 	loop.RemoveIdle(*this);
-#endif
-#ifdef USE_GLIB_EVENTLOOP
-	g_source_remove(source_id);
-	source_id = 0;
-#endif
 }
 
 void
@@ -50,13 +44,8 @@ IdleMonitor::Schedule()
 		/* already scheduled */
 		return;
 
-#ifdef USE_INTERNAL_EVENTLOOP
 	active = true;
 	loop.AddIdle(*this);
-#endif
-#ifdef USE_GLIB_EVENTLOOP
-	source_id = loop.AddIdle(Callback, this);
-#endif
 }
 
 void
@@ -64,26 +53,8 @@ IdleMonitor::Run()
 {
 	assert(loop.IsInside());
 
-#ifdef USE_INTERNAL_EVENTLOOP
 	assert(active);
 	active = false;
-#endif
-#ifdef USE_GLIB_EVENTLOOP
-	assert(source_id != 0);
-	source_id = 0;
-#endif
 
 	OnIdle();
 }
-
-#ifdef USE_GLIB_EVENTLOOP
-
-gboolean
-IdleMonitor::Callback(gpointer data)
-{
-	IdleMonitor &monitor = *(IdleMonitor *)data;
-	monitor.Run();
-	return false;
-}
-
-#endif
diff --git a/src/event/IdleMonitor.hxx b/src/event/IdleMonitor.hxx
index 6f7365532..8d3928583 100644
--- a/src/event/IdleMonitor.hxx
+++ b/src/event/IdleMonitor.hxx
@@ -22,10 +22,6 @@
 
 #include "check.h"
 
-#ifdef USE_GLIB_EVENTLOOP
-#include <glib.h>
-#endif
-
 class EventLoop;
 
 /**
@@ -38,30 +34,15 @@ class EventLoop;
  * as thread-safe.
  */
 class IdleMonitor {
-#ifdef USE_INTERNAL_EVENTLOOP
 	friend class EventLoop;
-#endif
 
 	EventLoop &loop;
 
-#ifdef USE_INTERNAL_EVENTLOOP
 	bool active;
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-	guint source_id;
-#endif
 
 public:
-#ifdef USE_INTERNAL_EVENTLOOP
 	IdleMonitor(EventLoop &_loop)
 		:loop(_loop), active(false) {}
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-	IdleMonitor(EventLoop &_loop)
-		:loop(_loop), source_id(0) {}
-#endif
 
 	~IdleMonitor() {
 		Cancel();
@@ -72,13 +53,7 @@ public:
 	}
 
 	bool IsActive() const {
-#ifdef USE_INTERNAL_EVENTLOOP
 		return active;
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-		return source_id != 0;
-#endif
 	}
 
 	void Schedule();
@@ -89,9 +64,6 @@ protected:
 
 private:
 	void Run();
-#ifdef USE_GLIB_EVENTLOOP
-	static gboolean Callback(gpointer data);
-#endif
 };
 
 #endif /* MAIN_NOTIFY_H */
diff --git a/src/event/Loop.cxx b/src/event/Loop.cxx
index 06e1499e7..57c966bb7 100644
--- a/src/event/Loop.cxx
+++ b/src/event/Loop.cxx
@@ -20,8 +20,6 @@
 #include "config.h"
 #include "Loop.hxx"
 
-#ifdef USE_INTERNAL_EVENTLOOP
-
 #include "system/Clock.hxx"
 #include "TimeoutMonitor.hxx"
 #include "SocketMonitor.hxx"
@@ -104,15 +102,12 @@ EventLoop::CancelTimer(TimeoutMonitor &t)
 	}
 }
 
-#endif
-
 void
 EventLoop::Run()
 {
 	assert(thread.IsNull());
 	thread = ThreadId::GetCurrent();
 
-#ifdef USE_INTERNAL_EVENTLOOP
 	assert(!quit);
 
 	do {
@@ -180,17 +175,10 @@ EventLoop::Run()
 		poll_result.Reset();
 
 	} while (!quit);
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-	g_main_loop_run(loop);
-#endif
 
 	assert(thread.IsInside());
 }
 
-#ifdef USE_INTERNAL_EVENTLOOP
-
 void
 EventLoop::AddDeferred(DeferredMonitor &d)
 {
@@ -254,39 +242,3 @@ EventLoop::OnSocketReady(gcc_unused unsigned flags)
 
 	return true;
 }
-
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-
-guint
-EventLoop::AddIdle(GSourceFunc function, gpointer data)
-{
-	GSource *source = g_idle_source_new();
-	g_source_set_callback(source, function, data, nullptr);
-	guint id = g_source_attach(source, GetContext());
-	g_source_unref(source);
-	return id;
-}
-
-GSource *
-EventLoop::AddTimeout(guint interval_ms,
-		      GSourceFunc function, gpointer data)
-{
-	GSource *source = g_timeout_source_new(interval_ms);
-	g_source_set_callback(source, function, data, nullptr);
-	g_source_attach(source, GetContext());
-	return source;
-}
-
-GSource *
-EventLoop::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);
-	g_source_attach(source, GetContext());
-	return source;
-}
-
-#endif
diff --git a/src/event/Loop.hxx b/src/event/Loop.hxx
index 60d52ba52..5ac7d635f 100644
--- a/src/event/Loop.hxx
+++ b/src/event/Loop.hxx
@@ -24,7 +24,6 @@
 #include "thread/Id.hxx"
 #include "Compiler.h"
 
-#ifdef USE_INTERNAL_EVENTLOOP
 #include "PollGroup.hxx"
 #include "thread/Mutex.hxx"
 #include "WakeFD.hxx"
@@ -32,18 +31,11 @@
 
 #include <list>
 #include <set>
-#endif
 
-#ifdef USE_GLIB_EVENTLOOP
-#include <glib.h>
-#endif
-
-#ifdef USE_INTERNAL_EVENTLOOP
 class TimeoutMonitor;
 class IdleMonitor;
 class DeferredMonitor;
 class SocketMonitor;
-#endif
 
 #include <assert.h>
 
@@ -56,12 +48,8 @@ class SocketMonitor;
  *
  * @see SocketMonitor, MultiSocketMonitor, TimeoutMonitor, IdleMonitor
  */
-class EventLoop final
-#ifdef USE_INTERNAL_EVENTLOOP
-	: private SocketMonitor
-#endif
+class EventLoop final : SocketMonitor
 {
-#ifdef USE_INTERNAL_EVENTLOOP
 	struct TimerRecord {
 		/**
 		 * Projected monotonic_clock_ms() value when this
@@ -98,12 +86,6 @@ class EventLoop final
 
 	PollGroup poll_group;
 	PollResult poll_result;
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-	GMainContext *context;
-	GMainLoop *loop;
-#endif
 
 	/**
 	 * A reference to the thread that is currently inside Run().
@@ -111,7 +93,6 @@ class EventLoop final
 	ThreadId thread;
 
 public:
-#ifdef USE_INTERNAL_EVENTLOOP
 	struct Default {};
 
 	EventLoop(Default dummy=Default());
@@ -179,47 +160,6 @@ private:
 	virtual bool OnSocketReady(unsigned flags) override;
 
 public:
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-	EventLoop()
-		:context(g_main_context_new()),
-		 loop(g_main_loop_new(context, false)),
-		 thread(ThreadId::Null()) {}
-
-	struct Default {};
-	EventLoop(gcc_unused Default _dummy)
-		:context(g_main_context_ref(g_main_context_default())),
-		 loop(g_main_loop_new(context, false)),
-		 thread(ThreadId::Null()) {}
-
-	~EventLoop() {
-		g_main_loop_unref(loop);
-		g_main_context_unref(context);
-	}
-
-	GMainContext *GetContext() {
-		return context;
-	}
-
-	void WakeUp() {
-		g_main_context_wakeup(context);
-	}
-
-	void Break() {
-		g_main_loop_quit(loop);
-	}
-
-	void Run();
-
-	guint AddIdle(GSourceFunc function, gpointer data);
-
-	GSource *AddTimeout(guint interval_ms,
-			    GSourceFunc function, gpointer data);
-
-	GSource *AddTimeoutSeconds(guint interval_s,
-				   GSourceFunc function, gpointer data);
-#endif
 
 	/**
 	 * Are we currently running inside this EventLoop's thread?
diff --git a/src/event/MultiSocketMonitor.cxx b/src/event/MultiSocketMonitor.cxx
index f26ab6c28..a96229ef6 100644
--- a/src/event/MultiSocketMonitor.cxx
+++ b/src/event/MultiSocketMonitor.cxx
@@ -25,8 +25,6 @@
 
 #include <assert.h>
 
-#ifdef USE_INTERNAL_EVENTLOOP
-
 MultiSocketMonitor::MultiSocketMonitor(EventLoop &_loop)
 	:IdleMonitor(_loop), TimeoutMonitor(_loop), ready(false) {
 }
@@ -64,102 +62,3 @@ MultiSocketMonitor::OnIdle()
 		Prepare();
 	}
 }
-
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-
-/**
- * The vtable for our GSource implementation.  Unfortunately, we
- * cannot declare it "const", because g_source_new() takes a non-const
- * pointer, for whatever reason.
- */
-static GSourceFuncs multi_socket_monitor_source_funcs = {
-	MultiSocketMonitor::Prepare,
-	MultiSocketMonitor::Check,
-	MultiSocketMonitor::Dispatch,
-	nullptr,
-	nullptr,
-	nullptr,
-};
-
-MultiSocketMonitor::MultiSocketMonitor(EventLoop &_loop)
-	:loop(_loop),
-	 source((Source *)g_source_new(&multi_socket_monitor_source_funcs,
-				       sizeof(*source))),
-	 absolute_timeout_us(-1) {
-	source->monitor = this;
-
-	g_source_attach(&source->base, loop.GetContext());
-}
-
-MultiSocketMonitor::~MultiSocketMonitor()
-{
-	g_source_destroy(&source->base);
-	g_source_unref(&source->base);
-	source = nullptr;
-}
-
-bool
-MultiSocketMonitor::Prepare(gint *timeout_r)
-{
-	int timeout_ms = *timeout_r = PrepareSockets();
-	absolute_timeout_us = timeout_ms < 0
-		? uint64_t(-1)
-		: GetTime() + uint64_t(timeout_ms) * 1000;
-
-	return false;
-}
-
-bool
-MultiSocketMonitor::Check() const
-{
-	if (GetTime() >= absolute_timeout_us)
-		return true;
-
-	for (const auto &i : fds)
-		if (i.GetReturnedEvents() != 0)
-			return true;
-
-	return false;
-}
-
-/*
- * GSource methods
- *
- */
-
-gboolean
-MultiSocketMonitor::Prepare(GSource *_source, gint *timeout_r)
-{
-	Source &source = *(Source *)_source;
-	MultiSocketMonitor &monitor = *source.monitor;
-	assert(_source == &monitor.source->base);
-
-	return monitor.Prepare(timeout_r);
-}
-
-gboolean
-MultiSocketMonitor::Check(GSource *_source)
-{
-	const Source &source = *(const Source *)_source;
-	const MultiSocketMonitor &monitor = *source.monitor;
-	assert(_source == &monitor.source->base);
-
-	return monitor.Check();
-}
-
-gboolean
-MultiSocketMonitor::Dispatch(GSource *_source,
-			     gcc_unused GSourceFunc callback,
-			     gcc_unused gpointer user_data)
-{
-	Source &source = *(Source *)_source;
-	MultiSocketMonitor &monitor = *source.monitor;
-	assert(_source == &monitor.source->base);
-
-	monitor.Dispatch();
-	return true;
-}
-
-#endif
diff --git a/src/event/MultiSocketMonitor.hxx b/src/event/MultiSocketMonitor.hxx
index 680930037..2630e1d95 100644
--- a/src/event/MultiSocketMonitor.hxx
+++ b/src/event/MultiSocketMonitor.hxx
@@ -23,15 +23,9 @@
 #include "check.h"
 #include "Compiler.h"
 
-#ifdef USE_INTERNAL_EVENTLOOP
 #include "IdleMonitor.hxx"
 #include "TimeoutMonitor.hxx"
 #include "SocketMonitor.hxx"
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-#include <glib.h>
-#endif
 
 #include <forward_list>
 #include <iterator>
@@ -55,12 +49,8 @@ class EventLoop;
  * In PrepareSockets(), use UpdateSocketList() and AddSocket().
  * DispatchSockets() will be called if at least one socket is ready.
  */
-class MultiSocketMonitor
-#ifdef USE_INTERNAL_EVENTLOOP
-	: private IdleMonitor, private TimeoutMonitor
-#endif
+class MultiSocketMonitor : IdleMonitor, TimeoutMonitor
 {
-#ifdef USE_INTERNAL_EVENTLOOP
 	class SingleFD final : public SocketMonitor {
 		MultiSocketMonitor &multi;
 
@@ -105,99 +95,28 @@ class MultiSocketMonitor
 	friend class SingleFD;
 
 	bool ready, refresh;
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-	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_INTERNAL_EVENTLOOP
 	static constexpr unsigned READ = SocketMonitor::READ;
 	static constexpr unsigned WRITE = SocketMonitor::WRITE;
 	static constexpr unsigned ERROR = SocketMonitor::ERROR;
 	static constexpr unsigned HANGUP = SocketMonitor::HANGUP;
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-	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_INTERNAL_EVENTLOOP
 	using IdleMonitor::GetEventLoop;
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-	EventLoop &GetEventLoop() {
-		return loop;
-	}
-#endif
 
 public:
-#ifdef USE_GLIB_EVENTLOOP
-	gcc_pure
-	uint64_t GetTime() const {
-		return g_source_get_time(&source->base);
-	}
-#endif
-
 	void InvalidateSockets() {
-#ifdef USE_INTERNAL_EVENTLOOP
 		refresh = true;
 		IdleMonitor::Schedule();
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-		/* 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);
-#ifdef USE_GLIB_EVENTLOOP
-		g_source_add_poll(&source->base, &fds.front().pfd);
-#endif
 	}
 
 	template<typename E>
@@ -212,13 +131,7 @@ public:
 				i->SetEvents(events);
 				prev = i;
 			} else {
-#ifdef USE_INTERNAL_EVENTLOOP
 				i->Steal();
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-				g_source_remove_poll(&source->base, &i->pfd);
-#endif
 				fds.erase_after(prev);
 			}
 		}
@@ -231,7 +144,6 @@ protected:
 	virtual int PrepareSockets() = 0;
 	virtual void DispatchSockets() = 0;
 
-#ifdef USE_INTERNAL_EVENTLOOP
 private:
 	void SetReady() {
 		ready = true;
@@ -246,25 +158,6 @@ private:
 	}
 
 	virtual void OnIdle() final;
-
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-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
diff --git a/src/event/SocketMonitor.cxx b/src/event/SocketMonitor.cxx
index 769efba82..92693949f 100644
--- a/src/event/SocketMonitor.cxx
+++ b/src/event/SocketMonitor.cxx
@@ -31,8 +31,6 @@
 #include <sys/socket.h>
 #endif
 
-#ifdef USE_INTERNAL_EVENTLOOP
-
 void
 SocketMonitor::Dispatch(unsigned flags)
 {
@@ -42,68 +40,6 @@ SocketMonitor::Dispatch(unsigned flags)
 		Cancel();
 }
 
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-
-/*
- * GSource methods
- *
- */
-
-gboolean
-SocketMonitor::Prepare(gcc_unused GSource *source, gcc_unused gint *timeout_r)
-{
-	return false;
-}
-
-gboolean
-SocketMonitor::Check(GSource *_source)
-{
-	const Source &source = *(const Source *)_source;
-	const SocketMonitor &monitor = *source.monitor;
-	assert(_source == &monitor.source->base);
-
-	return monitor.Check();
-}
-
-gboolean
-SocketMonitor::Dispatch(GSource *_source,
-			gcc_unused GSourceFunc callback,
-			gcc_unused gpointer user_data)
-{
-	Source &source = *(Source *)_source;
-	SocketMonitor &monitor = *source.monitor;
-	assert(_source == &monitor.source->base);
-
-	monitor.Dispatch();
-	return true;
-}
-
-/**
- * The vtable for our GSource implementation.  Unfortunately, we
- * cannot declare it "const", because g_source_new() takes a non-const
- * pointer, for whatever reason.
- */
-static GSourceFuncs socket_monitor_source_funcs = {
-	SocketMonitor::Prepare,
-	SocketMonitor::Check,
-	SocketMonitor::Dispatch,
-	nullptr,
-	nullptr,
-	nullptr,
-};
-
-SocketMonitor::SocketMonitor(int _fd, EventLoop &_loop)
-	:fd(-1), loop(_loop),
-	 source(nullptr) {
-	assert(_fd >= 0);
-
-	Open(_fd);
-}
-
-#endif
-
 SocketMonitor::~SocketMonitor()
 {
 	if (IsDefined())
@@ -114,23 +50,9 @@ void
 SocketMonitor::Open(int _fd)
 {
 	assert(fd < 0);
-#ifdef USE_GLIB_EVENTLOOP
-	assert(source == nullptr);
-#endif
 	assert(_fd >= 0);
 
 	fd = _fd;
-
-#ifdef USE_GLIB_EVENTLOOP
-	poll = {fd, 0, 0};
-
-	source = (Source *)g_source_new(&socket_monitor_source_funcs,
-					sizeof(*source));
-	source->monitor = this;
-
-	g_source_attach(&source->base, loop.GetContext());
-	g_source_add_poll(&source->base, &poll);
-#endif
 }
 
 int
@@ -143,12 +65,6 @@ SocketMonitor::Steal()
 	int result = fd;
 	fd = -1;
 
-#ifdef USE_GLIB_EVENTLOOP
-	g_source_destroy(&source->base);
-	g_source_unref(&source->base);
-	source = nullptr;
-#endif
-
 	return result;
 }
 
@@ -157,13 +73,9 @@ SocketMonitor::Abandon()
 {
 	assert(IsDefined());
 
-#ifdef USE_INTERNAL_EVENTLOOP
 	int old_fd = fd;
 	fd = -1;
 	loop.Abandon(old_fd, *this);
-#else
-	Steal();
-#endif
 }
 
 void
@@ -180,7 +92,6 @@ SocketMonitor::Schedule(unsigned flags)
 	if (flags == GetScheduledFlags())
 		return;
 
-#ifdef USE_INTERNAL_EVENTLOOP
 	if (scheduled_flags == 0)
 		loop.AddFD(fd, flags, *this);
 	else if (flags == 0)
@@ -189,14 +100,6 @@ SocketMonitor::Schedule(unsigned flags)
 		loop.ModifyFD(fd, flags, *this);
 
 	scheduled_flags = flags;
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-	poll.events = flags;
-	poll.revents &= flags;
-
-	loop.WakeUp();
-#endif
 }
 
 SocketMonitor::ssize_t
diff --git a/src/event/SocketMonitor.hxx b/src/event/SocketMonitor.hxx
index 768f21c57..3a84dc094 100644
--- a/src/event/SocketMonitor.hxx
+++ b/src/event/SocketMonitor.hxx
@@ -21,14 +21,7 @@
 #define MPD_SOCKET_MONITOR_HXX
 
 #include "check.h"
-
-#ifdef USE_INTERNAL_EVENTLOOP
 #include "PollGroup.hxx"
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-#include <glib.h>
-#endif
 
 #include <type_traits>
 
@@ -56,60 +49,27 @@ class EventLoop;
  * as thread-safe.
  */
 class SocketMonitor {
-#ifdef USE_GLIB_EVENTLOOP
-	struct Source {
-		GSource base;
-
-		SocketMonitor *monitor;
-	};
-#endif
-
 	int fd;
 	EventLoop &loop;
 
-#ifdef USE_INTERNAL_EVENTLOOP
 	/**
 	 * A bit mask of events that is currently registered in the EventLoop.
 	 */
 	unsigned scheduled_flags;
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-	Source *source;
-	GPollFD poll;
-#endif
 
 public:
-#ifdef USE_INTERNAL_EVENTLOOP
 	static constexpr unsigned READ = PollGroup::READ;
 	static constexpr unsigned WRITE = PollGroup::WRITE;
 	static constexpr unsigned ERROR = PollGroup::ERROR;
 	static constexpr unsigned HANGUP = PollGroup::HANGUP;
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-	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 
 
 	typedef std::make_signed<size_t>::type ssize_t;
 
-#ifdef USE_INTERNAL_EVENTLOOP
 	SocketMonitor(EventLoop &_loop)
 		:fd(-1), loop(_loop), scheduled_flags(0) {}
 
 	SocketMonitor(int _fd, EventLoop &_loop)
 		:fd(_fd), loop(_loop), scheduled_flags(0) {}
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-	SocketMonitor(EventLoop &_loop)
-		:fd(-1), loop(_loop), source(nullptr) {}
-
-	SocketMonitor(int _fd, EventLoop &_loop);
-#endif
 
 	~SocketMonitor();
 
@@ -145,13 +105,7 @@ public:
 	unsigned GetScheduledFlags() const {
 		assert(IsDefined());
 
-#ifdef USE_INTERNAL_EVENTLOOP
 		return scheduled_flags;
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-		return poll.events;
-#endif
 	}
 
 	void Schedule(unsigned flags);
@@ -186,30 +140,7 @@ protected:
 	virtual bool OnSocketReady(unsigned flags) = 0;
 
 public:
-#ifdef USE_INTERNAL_EVENTLOOP
 	void Dispatch(unsigned flags);
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-	/* 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 {
-		assert(IsDefined());
-
-		return (poll.revents & poll.events) != 0;
-	}
-
-	void Dispatch() {
-		assert(IsDefined());
-
-		OnSocketReady(poll.revents & poll.events);
-	}
-#endif
 };
 
 #endif
diff --git a/src/event/TimeoutMonitor.cxx b/src/event/TimeoutMonitor.cxx
index 3d7d46324..55260af2a 100644
--- a/src/event/TimeoutMonitor.cxx
+++ b/src/event/TimeoutMonitor.cxx
@@ -25,32 +25,19 @@ void
 TimeoutMonitor::Cancel()
 {
 	if (IsActive()) {
-#ifdef USE_INTERNAL_EVENTLOOP
 		active = false;
 		loop.CancelTimer(*this);
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-		g_source_destroy(source);
-		g_source_unref(source);
-		source = nullptr;
-#endif
 	}
 }
 
 void
+
 TimeoutMonitor::Schedule(unsigned ms)
 {
 	Cancel();
 
-#ifdef USE_INTERNAL_EVENTLOOP
 	active = true;
 	loop.AddTimer(*this, ms);
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-	source = loop.AddTimeout(ms, Callback, this);
-#endif
 }
 
 void
@@ -58,33 +45,11 @@ TimeoutMonitor::ScheduleSeconds(unsigned s)
 {
 	Cancel();
 
-#ifdef USE_INTERNAL_EVENTLOOP
 	Schedule(s * 1000u);
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-	source = loop.AddTimeoutSeconds(s, Callback, this);
-#endif
 }
 
 void
 TimeoutMonitor::Run()
 {
-#ifdef USE_GLIB_EVENTLOOP
-	Cancel();
-#endif
-
 	OnTimeout();
 }
-
-#ifdef USE_GLIB_EVENTLOOP
-
-gboolean
-TimeoutMonitor::Callback(gpointer data)
-{
-	TimeoutMonitor &monitor = *(TimeoutMonitor *)data;
-	monitor.Run();
-	return false;
-}
-
-#endif
diff --git a/src/event/TimeoutMonitor.hxx b/src/event/TimeoutMonitor.hxx
index 9f6b19bc7..0e3f4bdb7 100644
--- a/src/event/TimeoutMonitor.hxx
+++ b/src/event/TimeoutMonitor.hxx
@@ -22,10 +22,6 @@
 
 #include "check.h"
 
-#ifdef USE_GLIB_EVENTLOOP
-#include <glib.h>
-#endif
-
 class EventLoop;
 
 /**
@@ -37,31 +33,16 @@ class EventLoop;
  * as thread-safe.
  */
 class TimeoutMonitor {
-#ifdef USE_INTERNAL_EVENTLOOP
 	friend class EventLoop;
-#endif
 
 	EventLoop &loop;
 
-#ifdef USE_INTERNAL_EVENTLOOP
 	bool active;
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-	GSource *source;
-#endif
 
 public:
-#ifdef USE_INTERNAL_EVENTLOOP
 	TimeoutMonitor(EventLoop &_loop)
 		:loop(_loop), active(false) {
 	}
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-	TimeoutMonitor(EventLoop &_loop)
-		:loop(_loop), source(nullptr) {}
-#endif
 
 	~TimeoutMonitor() {
 		Cancel();
@@ -72,13 +53,7 @@ public:
 	}
 
 	bool IsActive() const {
-#ifdef USE_INTERNAL_EVENTLOOP
 		return active;
-#endif
-
-#ifdef USE_GLIB_EVENTLOOP
-		return source != nullptr;
-#endif
 	}
 
 	void Schedule(unsigned ms);
@@ -90,10 +65,6 @@ protected:
 
 private:
 	void Run();
-
-#ifdef USE_GLIB_EVENTLOOP
-	static gboolean Callback(gpointer data);
-#endif
 };
 
 #endif /* MAIN_NOTIFY_H */