Update list, rculist and hlist

[urcu.git] / urcu / hlist.h

diff --git a/urcu/hlist.h b/urcu/hlist.h
new file mode 100644 (file)
index 0000000..1bec11a
--- /dev/null
+++ b/urcu/hlist.h
@@ -0,0 +1,73 @@
+#ifndef _KCOMPAT_HLIST_H
+#define _KCOMPAT_HLIST_H
+
+/*
+ * Kernel sourcecode compatible lightweight single pointer list head useful
+ * for implementing hash tables
+ *
+ * Copyright (C) 2009 Novell Inc.
+ *
+ * Author: Jan Blunck <jblunck@suse.de>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free  Software Foundation.
+ */
+
+struct hlist_head
+{
+       struct hlist_node *next;
+};
+
+struct hlist_node
+{
+       struct hlist_node *next;
+       struct hlist_node *prev;
+};
+
+/* Initialize a new list head.  */
+static inline void  INIT_HLIST_HEAD(struct hlist_head *ptr)
+{
+       ptr->next = NULL;
+}
+
+/* Get typed element from list at a given position.  */
+#define hlist_entry(ptr, type, member)                                 \
+       ((type *) ((char *) (ptr) - (unsigned long) (&((type *) 0)->member)))
+
+/* Add new element at the head of the list.  */
+static inline void hlist_add_head (struct hlist_node *newp,
+                                  struct hlist_head *head)
+{
+       if (head->next)
+               head->next->prev = newp;
+
+       newp->next = head->next;
+       newp->prev = (struct hlist_node *)head;
+       head->next = newp;
+}
+
+/* Remove element from list.  */
+static inline void hlist_del (struct hlist_node *elem)
+{
+       if (elem->next)
+               elem->next->prev = elem->prev;
+
+       elem->prev->next = elem->next;
+}
+
+#define hlist_for_each_entry(entry, pos, head, member)                 \
+       for (pos = (head)->next,                                        \
+                    entry = hlist_entry(pos, typeof(*entry), member);  \
+            pos != NULL;                                               \
+            pos = pos->next,                                   \
+                    entry = hlist_entry(pos, typeof(*entry), member))
+
+#define hlist_for_each_entry_safe(entry, pos, p, head, member)         \
+       for (pos = (head)->next,                                        \
+                    entry = hlist_entry(pos, typeof(*entry), member);  \
+            (pos != NULL) && ({ p = pos->next; 1;});                   \
+            pos = p,                                                   \
+                    entry = hlist_entry(pos, typeof(*entry), member))
+
+#endif /* _KCOMPAT_HLIST_H */