core: Defragment databases on startup

Databases can change either as part of an upgrade or through adding and
removing entries.  We can save a bit of memory by removing unallocated
entries during startup.

Implements #47: Automatic database defragment
Signed-off-by: Anna Schumaker <Anna@NoWheyCreamery.com>

core/core.c

@@ -9,6 +9,15 @@
 #include <core/tags/tags.h>
 
 
+static bool core_defragment(void *data)
+{
+	if (tags_defragment()) {
+		playlist_save();
+		audio_save();
+	}
+	return true;
+}
+
 void core_init(int *argc, char ***argv, struct core_init_data *init)
 {
 #ifdef CONFIG_TESTING
@@ -20,6 +29,8 @@ void core_init(int *argc, char ***argv, struct core_init_data *init)
 	tags_init();
 	playlist_init(init->playlist_ops);
 	audio_init(argc, argv, init->audio_ops);
+
+	idle_schedule(IDLE_SYNC, core_defragment, NULL);
 }
 
 void core_deinit()

core/tags/album.c

@@ -300,6 +300,11 @@ void album_db_deinit()
 	db_deinit(&album_db);
 }
 
+bool album_db_defrag()
+{
+	return db_defrag(&album_db);
+}
+
 bool album_db_upgrade_done()
 {
 	struct db_entry *dbe, *next;

core/tags/library.c

@@ -73,6 +73,11 @@ void library_db_deinit()
 	db_deinit(&library_db);
 }
 
+bool library_db_defrag()
+{
+	return db_defrag(&library_db);
+}
+
 const struct database *library_db_get()
 {
 	return &library_db;

core/tags/tags.c

@@ -35,3 +35,14 @@ void tags_deinit()
 	album_db_deinit();
 	artist_db_deinit();
 }
+
+bool tags_defragment(void *data)
+{
+	bool album   = album_db_defrag();
+	bool library = library_db_defrag();
+	bool track   = track_db_defrag();
+
+	if (album || library || track)
+		track_db_commit();
+	return track;
+}

core/tags/track.c

@@ -212,6 +212,11 @@ void track_db_commit()
 	db_save(&track_db);
 }
 
+bool track_db_defrag()
+{
+	return db_defrag(&track_db);
+}
+
 const struct database *track_db_get()
 {
 	return &track_db;

include/core/tags/album.h

@@ -36,6 +36,9 @@ void album_db_init();
 /* Called to clean up the album database. */
 void album_db_deinit();
 
+/* Called to defragment the album database. */
+bool album_db_defrag();
+
 /* Called to clean up the album database after an upgrade. */
 bool album_db_upgrade_done();
 

include/core/tags/library.h

@@ -30,6 +30,9 @@ void library_db_init();
 /* Called to clean up the library database. */
 void library_db_deinit();
 
+/* Called to defragment the library database. */
+bool library_db_defrag();
+
 /* Called to access the library database. */
 const struct database *library_db_get();
 

include/core/tags/tags.h

@@ -11,4 +11,7 @@ void tags_init();
 /* Called to clean up all databases. */
 void tags_deinit();
 
+/* Called to defragment all databases. */
+bool tags_defragment();
+
 #endif /* OCARINA_CORE_TAGS_TAGS_H */

include/core/tags/track.h

@@ -69,6 +69,9 @@ void track_db_deinit();
 /* Called to commit the track database. */
 void track_db_commit();
 
+/* Called to defragment the track database. */
+bool track_db_defrag();
+
 /* Called to access the track database. */
 const struct database *track_db_get();