1 files changed, 65 insertions, 0 deletions
diff --git a/firmware/os/inc/list.h b/firmware/os/inc/list.h
new file mode 100644
index 00000000..c892e421
--- /dev/null
+++ b/firmware/os/inc/list.h
@@ -0,0 +1,65 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef _LIST_H_
+#define _LIST_H_
+
+#include <stdbool.h>
+
+struct link_t
+{
+    struct link_t *prev, *next;
+} typedef link_t;
+
+#define list_iterate(list, cur_link, tmp_link)                  \
+    for ((cur_link) = (list)->next,                             \
+            (tmp_link) = (cur_link) ? (cur_link)->next : NULL;  \
+         (cur_link) != NULL && (cur_link) != (list);            \
+         (cur_link) = (tmp_link), (tmp_link) = (cur_link)->next)
+
+#define DECLARE_LIST(list) \
+    link_t list = { .prev = &list, .next = &list }
+
+static inline void list_init(struct link_t *list)
+{
+    list->prev = list->next = list;
+}
+
+static inline void list_add_tail(struct link_t *list, struct link_t *item)
+{
+    if (!list->next)
+        list_init(list);
+
+    item->prev = list->prev;
+    item->next = list;
+    list->prev->next = item;
+    list->prev = item;
+}
+
+static inline void list_delete(struct link_t *item)
+{
+    item->prev->next = item->next;
+    item->next->prev = item->prev;
+    item->next = item->prev = item;
+}
+
+static inline bool list_is_empty(struct link_t *list)
+{
+    return !list->next || list->next == list;
+}
+
+#endif
+