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-rw-r--r--lib/blkid/list.h184
1 files changed, 184 insertions, 0 deletions
diff --git a/lib/blkid/list.h b/lib/blkid/list.h
new file mode 100644
index 0000000..eb1c513
--- /dev/null
+++ b/lib/blkid/list.h
@@ -0,0 +1,184 @@
+#if !defined(_BLKID_LIST_H) && !defined(LIST_HEAD_INIT)
+#define _BLKID_LIST_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifdef HAVE_INTTYPES_H
+#include <inttypes.h>
+#else
+#ifdef HAVE_STDINT_H
+#include <stdint.h>
+#endif
+#endif
+
+#ifdef __GNUC__
+#define _INLINE_ static __inline__
+#else /* For Watcom C */
+#define _INLINE_ static inline
+#endif
+
+/*
+ * Simple doubly linked list implementation.
+ *
+ * Some of the internal functions ("__xxx") are useful when
+ * manipulating whole lists rather than single entries, as
+ * sometimes we already know the next/prev entries and we can
+ * generate better code by using them directly rather than
+ * using the generic single-entry routines.
+ */
+
+struct list_head {
+ struct list_head *next, *prev;
+};
+
+#define LIST_HEAD_INIT(name) { &(name), &(name) }
+
+#define INIT_LIST_HEAD(ptr) do { \
+ (ptr)->next = (ptr); (ptr)->prev = (ptr); \
+} while (0)
+
+/*
+ * Insert a new entry between two known consecutive entries.
+ *
+ * This is only for internal list manipulation where we know
+ * the prev/next entries already!
+ */
+_INLINE_ void __list_add(struct list_head * add,
+ struct list_head * prev,
+ struct list_head * next)
+{
+ next->prev = add;
+ add->next = next;
+ add->prev = prev;
+ prev->next = add;
+}
+
+/**
+ * list_add - add a new entry
+ * @add: new entry to be added
+ * @head: list head to add it after
+ *
+ * Insert a new entry after the specified head.
+ * This is good for implementing stacks.
+ */
+_INLINE_ void list_add(struct list_head *add, struct list_head *head)
+{
+ __list_add(add, head, head->next);
+}
+
+/**
+ * list_add_tail - add a new entry
+ * @add: new entry to be added
+ * @head: list head to add it before
+ *
+ * Insert a new entry before the specified head.
+ * This is useful for implementing queues.
+ */
+_INLINE_ void list_add_tail(struct list_head *add, struct list_head *head)
+{
+ __list_add(add, head->prev, head);
+}
+
+/*
+ * Delete a list entry by making the prev/next entries
+ * point to each other.
+ *
+ * This is only for internal list manipulation where we know
+ * the prev/next entries already!
+ */
+_INLINE_ void __list_del(struct list_head * prev,
+ struct list_head * next)
+{
+ next->prev = prev;
+ prev->next = next;
+}
+
+/**
+ * list_del - deletes entry from list.
+ * @entry: the element to delete from the list.
+ *
+ * list_empty() on @entry does not return true after this, @entry is
+ * in an undefined state.
+ */
+_INLINE_ void list_del(struct list_head *entry)
+{
+ __list_del(entry->prev, entry->next);
+}
+
+/**
+ * list_del_init - deletes entry from list and reinitialize it.
+ * @entry: the element to delete from the list.
+ */
+_INLINE_ void list_del_init(struct list_head *entry)
+{
+ __list_del(entry->prev, entry->next);
+ INIT_LIST_HEAD(entry);
+}
+
+/**
+ * list_empty - tests whether a list is empty
+ * @head: the list to test.
+ */
+_INLINE_ int list_empty(struct list_head *head)
+{
+ return head->next == head;
+}
+
+/**
+ * list_splice - join two lists
+ * @list: the new list to add.
+ * @head: the place to add it in the first list.
+ */
+_INLINE_ void list_splice(struct list_head *list, struct list_head *head)
+{
+ struct list_head *first = list->next;
+
+ if (first != list) {
+ struct list_head *last = list->prev;
+ struct list_head *at = head->next;
+
+ first->prev = head;
+ head->next = first;
+
+ last->next = at;
+ at->prev = last;
+ }
+}
+
+/**
+ * list_entry - get the struct for this entry
+ * @ptr: the &struct list_head pointer.
+ * @type: the type of the struct this is embedded in.
+ * @member: the name of the list_struct within the struct.
+ */
+#define list_entry(ptr, type, member) \
+ ((type *)((char *)(ptr)-(unsigned long)(intptr_t)(&((type *)0)->member)))
+
+/**
+ * list_for_each - iterate over elements in a list
+ * @pos: the &struct list_head to use as a loop counter.
+ * @head: the head for your list.
+ */
+#define list_for_each(pos, head) \
+ for (pos = (head)->next; pos != (head); pos = pos->next)
+
+/**
+ * list_for_each_safe - iterate over elements in a list, but don't dereference
+ * pos after the body is done (in case it is freed)
+ * @pos: the &struct list_head to use as a loop counter.
+ * @pnext: the &struct list_head to use as a pointer to the next item.
+ * @head: the head for your list (not included in iteration).
+ */
+#define list_for_each_safe(pos, pnext, head) \
+ for (pos = (head)->next, pnext = pos->next; pos != (head); \
+ pos = pnext, pnext = pos->next)
+
+#undef _INLINE_
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _BLKID_LIST_H */