1 files changed, 108 insertions, 0 deletions
diff --git a/klippy/list.h b/klippy/list.h
new file mode 100644
index 000000000..317a109cf
--- /dev/null
+++ b/klippy/list.h
@@ -0,0 +1,108 @@
+#ifndef __LIST_H
+#define __LIST_H
+
+#define container_of(ptr, type, member) ({                      \
+        const typeof( ((type *)0)->member ) *__mptr = (ptr);    \
+        (type *)( (char *)__mptr - offsetof(type,member) );})
+
+
+/****************************************************************
+ * list - Double linked lists
+ ****************************************************************/
+
+struct list_node {
+    struct list_node *next, *prev;
+};
+
+struct list_head {
+    struct list_node root;
+};
+
+static inline void
+list_init(struct list_head *h)
+{
+    h->root.prev = h->root.next = &h->root;
+}
+
+static inline int
+list_empty(const struct list_head *h)
+{
+    return h->root.next == &h->root;
+}
+
+static inline void
+list_del(struct list_node *n)
+{
+    struct list_node *prev = n->prev;
+    struct list_node *next = n->next;
+    next->prev = prev;
+    prev->next = next;
+}
+
+static inline void
+__list_add(struct list_node *n, struct list_node *prev, struct list_node *next)
+{
+    next->prev = n;
+    n->next = next;
+    n->prev = prev;
+    prev->next = n;
+}
+
+static inline void
+list_add_after(struct list_node *n, struct list_node *prev)
+{
+    __list_add(n, prev, prev->next);
+}
+
+static inline void
+list_add_before(struct list_node *n, struct list_node *next)
+{
+    __list_add(n, next->prev, next);
+}
+
+static inline void
+list_add_head(struct list_node *n, struct list_head *h)
+{
+    list_add_after(n, &h->root);
+}
+
+static inline void
+list_add_tail(struct list_node *n, struct list_head *h)
+{
+    list_add_before(n, &h->root);
+}
+
+static inline void
+list_join_tail(struct list_head *add, struct list_head *h)
+{
+    if (!list_empty(add)) {
+        struct list_node *prev = h->root.prev;
+        struct list_node *next = &h->root;
+        struct list_node *first = add->root.next;
+        struct list_node *last = add->root.prev;
+        first->prev = prev;
+        prev->next = first;
+        last->next = next;
+        next->prev = last;
+    }
+}
+
+#define list_next_entry(pos, member)                            \
+    container_of((pos)->member.next, typeof(*pos), member)
+
+#define list_first_entry(head, type, member)                    \
+    container_of((head)->root.next, type, member)
+
+#define list_for_each_entry(pos, head, member)                  \
+    for (pos = list_first_entry((head), typeof(*pos), member)   \
+         ; &pos->member != &(head)->root                        \
+         ; pos = list_next_entry(pos, member))
+
+#define list_for_each_entry_safe(pos, n, head, member)          \
+    for (pos = list_first_entry((head), typeof(*pos), member)   \
+          , n = list_next_entry(pos, member)                    \
+         ; &pos->member != &(head)->root                        \
+         ; pos = n, n = list_next_entry(n, member))
+
+
+#endif // list.h