--- /dev/null
+#ifndef CCAN_LIST_H
+#define CCAN_LIST_H
+#include <stdbool.h>
+#include "container_of/container_of.h"
+
+/**
+ * struct list_node - an entry in a doubly-linked list
+ * @next: next entry (self if empty)
+ * @prev: previous entry (self if empty)
+ *
+ * This is used as an entry in a linked list.
+ * Example:
+ * struct child {
+ * const char *name;
+ * // Linked list of all us children.
+ * struct list_node list;
+ * };
+ */
+struct list_node
+{
+ struct list_node *next, *prev;
+};
+
+/**
+ * struct list_head - the head of a doubly-linked list
+ * @h: the list_head (containing next and prev pointers)
+ *
+ * This is used as the head of a linked list.
+ * Example:
+ * struct parent {
+ * const char *name;
+ * struct list_head children;
+ * unsigned int num_children;
+ * };
+ */
+struct list_head
+{
+ struct list_node n;
+};
+
+/**
+ * list_check - check a list for consistency
+ * @h: the list_head
+ * @abortstr: the location to print on aborting, or NULL.
+ *
+ * Because list_nodes have redundant information, consistency checking between
+ * the back and forward links can be done. This is useful as a debugging check.
+ * If @abortstr is non-NULL, that will be printed in a diagnostic if the list
+ * is inconsistent, and the function will abort.
+ *
+ * Returns the list head if the list is consistent, NULL if not (it
+ * can never return NULL if @abortstr is set).
+ *
+ * Example:
+ * static void dump_parent(struct parent *p)
+ * {
+ * struct child *c;
+ *
+ * printf("%s (%u children):\n", p->name, parent->num_children);
+ * list_check(&p->children, "bad child list");
+ * list_for_each(&p->children, c, list)
+ * printf(" -> %s\n", c->name);
+ * }
+ */
+struct list_head *list_check(struct list_head *h, const char *abortstr);
+
+#ifdef CCAN_LIST_DEBUG
+#define debug_list(h) list_check((h), __func__)
+#else
+#define debug_list(h) (h)
+#endif
+
+/**
+ * list_head_init - initialize a list_head
+ * @h: the list_head to set to the empty list
+ *
+ * Example:
+ * list_head_init(&parent->children);
+ * parent->num_children = 0;
+ */
+static inline void list_head_init(struct list_head *h)
+{
+ h->n.next = h->n.prev = &h->n;
+}
+
+/**
+ * LIST_HEAD - define and initalized empty list_head
+ * @name: the name of the list.
+ *
+ * The LIST_HEAD macro defines a list_head and initializes it to an empty
+ * list. It can be prepended by "static" to define a static list_head.
+ *
+ * Example:
+ * // Header:
+ * extern struct list_head my_list;
+ *
+ * // C file:
+ * LIST_HEAD(my_list);
+ */
+#define LIST_HEAD(name) \
+ struct list_head name = { { &name.n, &name.n } }
+
+/**
+ * list_add - add an entry at the start of a linked list.
+ * @h: the list_head to add the node to
+ * @n: the list_node to add to the list.
+ *
+ * The list_node does not need to be initialized; it will be overwritten.
+ * Example:
+ * list_add(&parent->children, &child->list);
+ * parent->num_children++;
+ */
+static inline void list_add(struct list_head *h, struct list_node *n)
+{
+ n->next = h->n.next;
+ n->prev = &h->n;
+ h->n.next->prev = n;
+ h->n.next = n;
+ (void)debug_list(h);
+}
+
+/**
+ * list_add_tail - add an entry at the end of a linked list.
+ * @h: the list_head to add the node to
+ * @n: the list_node to add to the list.
+ *
+ * The list_node does not need to be initialized; it will be overwritten.
+ * Example:
+ * list_add_tail(&parent->children, &child->list);
+ * parent->num_children++;
+ */
+static inline void list_add_tail(struct list_head *h, struct list_node *n)
+{
+ n->next = &h->n;
+ n->prev = h->n.prev;
+ h->n.prev->next = n;
+ h->n.prev = n;
+ (void)debug_list(h);
+}
+
+/**
+ * list_del - delete an entry from a linked list.
+ * @n: the list_node to delete from the list.
+ *
+ * Example:
+ * list_del(&child->list);
+ * parent->num_children--;
+ */
+static inline void list_del(struct list_node *n)
+{
+ n->next->prev = n->prev;
+ n->prev->next = n->next;
+ (void)debug_list(n->next);
+#ifdef CCAN_LIST_DEBUG
+ /* Catch use-after-del. */
+ n->next = n->prev = NULL;
+#endif
+}
+
+/**
+ * list_empty - is a list empty?
+ * @h: the list_head
+ *
+ * If the list is empty, returns true.
+ *
+ * Example:
+ * assert(list_empty(&parent->children) == (parent->num_children == 0));
+ */
+static inline bool list_empty(struct list_head *h)
+{
+ (void)debug_list(h);
+ return h->n.next == &h->n;
+}
+
+/**
+ * list_entry - convert a list_node back into the structure containing it.
+ * @n: the list_node
+ * @type: the type of the entry
+ * @member: the list_node member of the type
+ *
+ * Example:
+ * struct child *c;
+ * // First list entry is children.next; convert back to child.
+ * c = list_entry(parent->children.next, struct child, list);
+ */
+#define list_entry(n, type, member) container_of(n, type, member)
+
+/**
+ * list_top - get the first entry in a list
+ * @h: the list_head
+ * @type: the type of the entry
+ * @member: the list_node member of the type
+ *
+ * If the list is empty, returns NULL.
+ *
+ * Example:
+ * struct child *first;
+ * first = list_top(&parent->children, struct child, list);
+ */
+#define list_top(h, type, member) \
+ list_entry(_list_top(h), type, member)
+
+static inline struct list_node *_list_top(struct list_head *h)
+{
+ (void)debug_list(h);
+ if (list_empty(h))
+ return NULL;
+ return h->n.next;
+}
+
+/**
+ * list_for_each - iterate through a list.
+ * @h: the list_head
+ * @i: the structure containing the list_node
+ * @member: the list_node member of the structure
+ *
+ * This is a convenient wrapper to iterate @i over the entire list. It's
+ * a for loop, so you can break and continue as normal.
+ *
+ * Example:
+ * struct child *c;
+ * list_for_each(&parent->children, c, list)
+ * printf("Name: %s\n", c->name);
+ */
+#define list_for_each(h, i, member) \
+ for (i = container_of_var(debug_list(h)->n.next, i, member); \
+ &i->member != &(h)->n; \
+ i = container_of_var(i->member.next, i, member))
+
+/**
+ * list_for_each_safe - iterate through a list, maybe during deletion
+ * @h: the list_head
+ * @i: the structure containing the list_node
+ * @nxt: the structure containing the list_node
+ * @member: the list_node member of the structure
+ *
+ * This is a convenient wrapper to iterate @i over the entire list. It's
+ * a for loop, so you can break and continue as normal. The extra variable
+ * @nxt is used to hold the next element, so you can delete @i from the list.
+ *
+ * Example:
+ * struct child *c, *n;
+ * list_for_each_safe(&parent->children, c, n, list) {
+ * list_del(&c->list);
+ * parent->num_children--;
+ * }
+ */
+#define list_for_each_safe(h, i, nxt, member) \
+ for (i = container_of_var(debug_list(h)->n.next, i, member), \
+ nxt = container_of_var(i->member.next, i, member); \
+ &i->member != &(h)->n; \
+ i = nxt, nxt = container_of_var(i->member.next, i, member))
+#endif /* CCAN_LIST_H */
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