audio: replaced parseAudioConfig() with audio_format_parse()

Added audio_format_parse() in a separate library, with a modern
interface: return a GError instead of logging errors.  This allows the
caller to deal with the error.

src/audio_parser.h

@@ -0,0 +1,36 @@
+/*
+ * 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
+ */
+
+/*
+ * Parser functions for audio related objects.
+ *
+ */
+
+#ifndef AUDIO_PARSER_H
+#define AUDIO_PARSER_H
+
+#include <glib.h>
+
+#include <stdbool.h>
+
+struct audio_format;
+
+bool
+audio_format_parse(struct audio_format *dest, const char *src, GError **error);
+
+#endif