command: added command "idle"

"idle" waits until something noteworthy happens on the server,
e.g. song change, playlist modified, database updated.  This allows
clients to keep up to date without polling.

1 files changed, 64 insertions, 0 deletions

diff --git a/src/idle.h b/src/idle.h
new file mode 100644
index 000000000..69756b153
--- /dev/null
+++ b/src/idle.h
@@ -0,0 +1,64 @@
+/* the Music Player Daemon (MPD)
+ * Copyright (C) 2008 Max Kellermann <max@duempel.org>
+ * This project's homepage is: 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+/*
+ * Support library for the "idle" command.
+ *
+ */
+
+#ifndef MPD_IDLE_H
+#define MPD_IDLE_H
+
+enum {
+	/** song database has been updated*/
+	IDLE_DATABASE = 0x1,
+
+	/** a stored playlist has been modified, created, deleted or
+	    renamed */
+	IDLE_STORED_PLAYLIST = 0x2,
+
+	/** the current playlist has been modified */
+	IDLE_PLAYLIST = 0x4,
+
+	/** the player state has changed: play, stop, pause, seek, ... */
+	IDLE_PLAYER = 0x8,
+
+	/** the volume has been modified */
+	IDLE_MIXER = 0x10,
+
+	/** an audio output device has been enabled or disabled */
+	IDLE_OUTPUT = 0x20,
+
+	/** options have changed: crossfade, random, repeat, ... */
+	IDLE_OPTIONS = 0x40,
+};
+
+/**
+ * Adds idle flag (with bitwise "or") and queues notifications to all
+ * clients.
+ */
+void
+idle_add(unsigned flags);
+
+/**
+ * Atomically reads and resets the global idle flags value.
+ */
+unsigned
+idle_get(void);
+
+#endif