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-rw-r--r--extras/multipath/libdevmapper/list.h99
1 files changed, 99 insertions, 0 deletions
diff --git a/extras/multipath/libdevmapper/list.h b/extras/multipath/libdevmapper/list.h
new file mode 100644
index 0000000000..df3d32aea8
--- /dev/null
+++ b/extras/multipath/libdevmapper/list.h
@@ -0,0 +1,99 @@
+/*
+ * Copyright (C) 2001 Sistina Software
+ *
+ * This file is released under the LGPL.
+ */
+
+#ifndef _LVM_LIST_H
+#define _LVM_LIST_H
+
+#include <assert.h>
+
+struct list {
+ struct list *n, *p;
+};
+
+#define LIST_INIT(name) struct list name = { &(name), &(name) }
+
+static inline void list_init(struct list *head)
+{
+ head->n = head->p = head;
+}
+
+static inline void list_add(struct list *head, struct list *elem)
+{
+ assert(head->n);
+
+ elem->n = head;
+ elem->p = head->p;
+
+ head->p->n = elem;
+ head->p = elem;
+}
+
+static inline void list_add_h(struct list *head, struct list *elem)
+{
+ assert(head->n);
+
+ elem->n = head->n;
+ elem->p = head;
+
+ head->n->p = elem;
+ head->n = elem;
+}
+
+static inline void list_del(struct list *elem)
+{
+ elem->n->p = elem->p;
+ elem->p->n = elem->n;
+}
+
+static inline int list_empty(struct list *head)
+{
+ return head->n == head;
+}
+
+static inline int list_end(struct list *head, struct list *elem)
+{
+ return elem->n == head;
+}
+
+static inline struct list *list_next(struct list *head, struct list *elem)
+{
+ return (list_end(head, elem) ? NULL : elem->n);
+}
+
+#define list_iterate(v, head) \
+ for (v = (head)->n; v != head; v = v->n)
+
+#define list_uniterate(v, head, start) \
+ for (v = (start)->p; v != head; v = v->p)
+
+#define list_iterate_safe(v, t, head) \
+ for (v = (head)->n, t = v->n; v != head; v = t, t = v->n)
+
+static inline unsigned int list_size(const struct list *head)
+{
+ unsigned int s = 0;
+ const struct list *v;
+
+ list_iterate(v, head)
+ s++;
+
+ return s;
+}
+
+#define list_item(v, t) \
+ ((t *)((uintptr_t)(v) - (uintptr_t)&((t *) 0)->list))
+
+#define list_struct_base(v, t, h) \
+ ((t *)((uintptr_t)(v) - (uintptr_t)&((t *) 0)->h))
+
+/* Given a known element in a known structure, locate another */
+#define struct_field(v, t, e, f) \
+ (((t *)((uintptr_t)(v) - (uintptr_t)&((t *) 0)->e))->f)
+
+/* Given a known element in a known structure, locate the list head */
+#define list_head(v, t, e) struct_field(v, t, e, list)
+
+#endif