--- /dev/null
+// SPDX-FileCopyrightText: 2002 Free Software Foundation, Inc.
+// SPDX-FileCopyrightText: 2009 Pierre-Marc Fournier
+// SPDX-FileCopyrightText: 2010 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+//
+// SPDX-License-Identifier: LGPL-2.1-or-later
+
+/*
+ * (originally part of the GNU C Library)
+ * Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
+ */
+
+#ifndef _LIST_H
+#define _LIST_H 1
+
+/*
+ * container_of - Get the address of an object containing a field.
+ *
+ * @ptr: pointer to the field.
+ * @type: type of the object.
+ * @member: name of the field within the object.
+ */
+#define container_of(ptr, type, member) \
+ __extension__ \
+ ({ \
+ const __typeof__(((type *) NULL)->member) * __ptr = (ptr); \
+ (type *)((char *)__ptr - offsetof(type, member)); \
+ })
+
+/*
+ * The definitions of this file are adopted from those which can be
+ * found in the Linux kernel headers to enable people familiar with the
+ * latter find their way in these sources as well.
+ */
+
+/* Basic type for the double-link list. */
+struct list_head {
+ struct list_head *next, *prev;
+};
+
+/* Define a variable with the head and tail of the list. */
+#define LIST_HEAD(name) \
+ struct list_head name = { &(name), &(name) }
+
+/* Initialize a new list head. */
+#define INIT_LIST_HEAD(ptr) \
+ (ptr)->next = (ptr)->prev = (ptr)
+
+#define LIST_HEAD_INIT(name) { .next = &(name), .prev = &(name) }
+
+/* Add new element at the head of the list. */
+static inline
+void list_add(struct list_head *newp, struct list_head *head)
+{
+ head->next->prev = newp;
+ newp->next = head->next;
+ newp->prev = head;
+ head->next = newp;
+}
+
+/* Add new element at the tail of the list. */
+static inline
+void list_add_tail(struct list_head *newp, struct list_head *head)
+{
+ head->prev->next = newp;
+ newp->next = head;
+ newp->prev = head->prev;
+ head->prev = newp;
+}
+
+/* Remove element from list. */
+static inline
+void __list_del(struct list_head *prev, struct list_head *next)
+{
+ next->prev = prev;
+ prev->next = next;
+}
+
+/* Remove element from list. */
+static inline
+void list_del(struct list_head *elem)
+{
+ __list_del(elem->prev, elem->next);
+}
+
+/* Remove element from list, initializing the element's list pointers. */
+static inline
+void list_del_init(struct list_head *elem)
+{
+ list_del(elem);
+ INIT_LIST_HEAD(elem);
+}
+
+/* Delete from list, add to another list as head. */
+static inline
+void list_move(struct list_head *elem, struct list_head *head)
+{
+ __list_del(elem->prev, elem->next);
+ list_add(elem, head);
+}
+
+/* Replace an old entry. */
+static inline
+void list_replace(struct list_head *old, struct list_head *_new)
+{
+ _new->next = old->next;
+ _new->prev = old->prev;
+ _new->prev->next = _new;
+ _new->next->prev = _new;
+}
+
+/* Join two lists. */
+static inline
+void list_splice(struct list_head *add, struct list_head *head)
+{
+ /* Do nothing if the list which gets added is empty. */
+ if (add != add->next) {
+ add->next->prev = head;
+ add->prev->next = head->next;
+ head->next->prev = add->prev;
+ head->next = add->next;
+ }
+}
+
+/* Get typed element from list at a given position. */
+#define list_entry(ptr, type, member) container_of(ptr, type, member)
+
+/* Get first entry from a list. */
+#define list_first_entry(ptr, type, member) \
+ list_entry((ptr)->next, type, member)
+
+/* Iterate forward over the elements of the list. */
+#define list_for_each(pos, head) \
+ for (pos = (head)->next; (pos) != (head); pos = (pos)->next)
+
+/*
+ * Iterate forward over the elements list. The list elements can be
+ * removed from the list while doing this.
+ */
+#define list_for_each_safe(pos, p, head) \
+ for (pos = (head)->next, p = (pos)->next; \
+ (pos) != (head); \
+ pos = (p), p = (pos)->next)
+
+/* Iterate backward over the elements of the list. */
+#define list_for_each_prev(pos, head) \
+ for (pos = (head)->prev; (pos) != (head); pos = (pos)->prev)
+
+/*
+ * Iterate backwards over the elements list. The list elements can be
+ * removed from the list while doing this.
+ */
+#define list_for_each_prev_safe(pos, p, head) \
+ for (pos = (head)->prev, p = (pos)->prev; \
+ (pos) != (head); \
+ pos = (p), p = (pos)->prev)
+
+#define list_for_each_entry(pos, head, member) \
+ for (pos = list_entry((head)->next, __typeof__(*(pos)), member); \
+ &(pos)->member != (head); \
+ pos = list_entry((pos)->member.next, __typeof__(*(pos)), member))
+
+#define list_for_each_entry_reverse(pos, head, member) \
+ for (pos = list_entry((head)->prev, __typeof__(*(pos)), member); \
+ &(pos)->member != (head); \
+ pos = list_entry((pos)->member.prev, __typeof__(*(pos)), member))
+
+#define list_for_each_entry_safe(pos, p, head, member) \
+ for (pos = list_entry((head)->next, __typeof__(*(pos)), member), \
+ p = list_entry((pos)->member.next, __typeof__(*(pos)), member); \
+ &(pos)->member != (head); \
+ pos = (p), p = list_entry((pos)->member.next, __typeof__(*(pos)), member))
+
+/*
+ * Same as list_for_each_entry_safe, but starts from "pos" which should
+ * point to an entry within the list.
+ */
+#define list_for_each_entry_safe_from(pos, p, head, member) \
+ for (p = list_entry((pos)->member.next, __typeof__(*(pos)), member); \
+ &(pos)->member != (head); \
+ pos = (p), p = list_entry((pos)->member.next, __typeof__(*(pos)), member))
+
+static inline
+int list_empty(struct list_head *head)
+{
+ return head == head->next;
+}
+
+static inline
+void list_replace_init(struct list_head *old, struct list_head *_new)
+{
+ struct list_head *head = old->next;
+
+ list_del(old);
+ list_add_tail(_new, head);
+ INIT_LIST_HEAD(old);
+}
+
+#endif /* _LIST_H */
projects / librseq.git / blobdiff