sticker: new library for storing dynamic information about songs

"Stickers" are pieces of information attached to existing MPD objects
(e.g. song files, directories, albums).  Clients can create arbitrary
name/value pairs.  MPD itself does not assume any special meaning in
them.

1 files changed, 86 insertions, 0 deletions

diff --git a/src/sticker.h b/src/sticker.h
new file mode 100644
index 000000000..ab3a35572
--- /dev/null
+++ b/src/sticker.h
@@ -0,0 +1,86 @@
+/*
+ * 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
+ */
+
+/*
+ * This is the sticker database library.  It is the backend of all the
+ * sticker code in MPD.
+ *
+ * "Stickers" are pieces of information attached to existing MPD
+ * objects (e.g. song files, directories, albums).  Clients can create
+ * arbitrary name/value pairs.  MPD itself does not assume any special
+ * meaning in them.
+ *
+ * The goal is to allow clients to share additional (possibly dynamic)
+ * information about songs, which is neither stored on the client (not
+ * available to other clients), nor stored in the song files (MPD has
+ * no write access).
+ *
+ * Client developers should create a standard for common sticker
+ * names, to ensure interoperability.
+ *
+ * Examples: song ratings; statistics; deferred tag writes; lyrics;
+ * ...
+ *
+ */
+
+#ifndef STICKER_H
+#define STICKER_H
+
+#include <stdbool.h>
+
+/**
+ * Opens the sticker database (if path is not NULL).
+ */
+void
+sticker_global_init(const char *path);
+
+/**
+ * Close the sticker database.
+ */
+void
+sticker_global_finish(void);
+
+/**
+ * Returns true if the sticker database is configured and available.
+ */
+bool
+sticker_enabled(void);
+
+/**
+ * Returns one value from an object's sticker record.  The caller must
+ * free the return value with g_free().
+ */
+char *
+sticker_load_value(const char *type, const char *uri, const char *name);
+
+/**
+ * Sets a sticker value in the specified object.  Overwrites existing
+ * values.
+ */
+bool
+sticker_store_value(const char *type, const char *uri,
+		    const char *name, const char *value);
+
+/**
+ * Deletes a sticker from the database.  All sticker values of the
+ * specified object are deleted.
+ */
+bool
+sticker_delete(const char *type, const char *uri);
+
+#endif