1 files changed, 69 insertions, 0 deletions

diff --git a/apps/plugins/mpegplayer/mpeg_linkedlist.h b/apps/plugins/mpegplayer/mpeg_linkedlist.h
new file mode 100644
index 0000000000..17123cc9ca
--- /dev/null
+++ b/apps/plugins/mpegplayer/mpeg_linkedlist.h
@@ -0,0 +1,69 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Linked list API declarations
+ *
+ * Copyright (c) 2007 Michael Sevakis
+ *
+ * All files in this archive are subject to the GNU General Public License.
+ * See the file COPYING in the source tree root for full license agreement.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+#ifndef MPEG_LINKEDLIST_H
+#define MPEG_LINKEDLIST_H
+
+struct list_item
+{
+    struct list_item *prev; /* previous item in list */
+    struct list_item *next; /* next item in list */
+};
+
+/* Utility macros to help get the actual structure pointer back */
+#define OFFSETOF(type, membername) ((off_t)&((type *)0)->membername)
+#define TYPE_FROM_MEMBER(type, memberptr, membername) \
+    ((type *)((intptr_t)(memberptr) - OFFSETOF(type, membername)))
+
+/* Initialize a master list head */
+void list_initialize(struct list_item *master_list_head);
+
+/* Are there items after the head item? */
+bool list_is_empty(struct list_item *head_item);
+
+/* Does the item belong to a list? */
+bool list_is_item_listed(struct list_item *item);
+
+/* Is the item a member in a particular list? */
+bool list_is_member(struct list_item *master_list_head,
+                    struct list_item *item);
+
+/* Remove an item from a list - no head item needed */
+void list_remove_item(struct list_item *item);
+
+/* Add a list item after the base item */
+void list_add_item(struct list_item *head_item,
+                   struct list_item *item);
+
+/* Clear list items after the head item */
+void list_clear_all(struct list_item *head_item);
+
+/* Enumerate all items after the head item - passing each item in turn
+ * to the callback as well as the data value. The current item may be
+ * safely removed. Items added after the current position will be enumated
+ * but not ones added before it. The callback may return false to stop
+ * the enumeration. */
+typedef bool (*list_enum_callback_t)(struct list_item *item, intptr_t data);
+
+void list_enum_items(struct list_item *head_item,
+                     list_enum_callback_t callback,
+                     intptr_t data);
+
+#endif /* MPEG_LINKEDLIST_H */