client: splitted client.c into several pieces

The soure file client.c has nearly 1000 lines, time for splitting it
into smaller pieces to improve readability.

src/client_expire.c

@@ -0,0 +1,89 @@
+/*
+ * Copyright (C) 2003-2009 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 "client_internal.h"
+
+static guint expire_source_id;
+
+void
+client_set_expired(struct client *client)
+{
+	if (!client_is_expired(client))
+		client_schedule_expire();
+
+	if (client->source_id != 0) {
+		g_source_remove(client->source_id);
+		client->source_id = 0;
+	}
+
+	if (client->channel != NULL) {
+		g_io_channel_unref(client->channel);
+		client->channel = NULL;
+	}
+}
+
+static void
+client_check_expired_callback(gpointer data, G_GNUC_UNUSED gpointer user_data)
+{
+	struct client *client = data;
+
+	if (client_is_expired(client)) {
+		g_debug("[%u] expired", client->num);
+		client_close(client);
+	} else if (!client->idle_waiting && /* idle clients
+					       never expire */
+		   (int)g_timer_elapsed(client->last_activity, NULL) >
+		   client_timeout) {
+		g_debug("[%u] timeout", client->num);
+		client_close(client);
+	}
+}
+
+static void
+client_manager_expire(void)
+{
+	client_list_foreach(client_check_expired_callback, NULL);
+}
+
+/**
+ * An idle event which calls client_manager_expire().
+ */
+static gboolean
+client_manager_expire_event(G_GNUC_UNUSED gpointer data)
+{
+	expire_source_id = 0;
+	client_manager_expire();
+	return false;
+}
+
+void
+client_schedule_expire(void)
+{
+	if (expire_source_id == 0)
+		/* delayed deletion */
+		expire_source_id = g_idle_add(client_manager_expire_event,
+					      NULL);
+}
+
+void
+client_deinit_expire(void)
+{
+	if (expire_source_id != 0)
+		g_source_remove(expire_source_id);
+}