audio: moved code to output_command.c

The output_command library provides a command interface to the audio
outputs.  It assumes the input comes from an untrusted source
(i.e. the client) and verifies all parameters.

src/output_command.h

@@ -0,0 +1,45 @@
+/*
+ * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+/*
+ * Glue functions for controlling the audio outputs over the MPD
+ * protocol.  These functions perform extra validation on all
+ * parameters, because they might be from an untrusted source.
+ *
+ */
+
+#ifndef OUTPUT_COMMAND_H
+#define OUTPUT_COMMAND_H
+
+#include <stdbool.h>
+
+/**
+ * Enables an audio output.  Returns false if the specified output
+ * does not exist.
+ */
+bool
+audio_output_enable_index(unsigned idx);
+
+/**
+ * Disables an audio output.  Returns false if the specified output
+ * does not exist.
+ */
+bool
+audio_output_disable_index(unsigned idx);
+
+#endif