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-rw-r--r--e2fsprogs/blkid/list.c110
1 files changed, 110 insertions, 0 deletions
diff --git a/e2fsprogs/blkid/list.c b/e2fsprogs/blkid/list.c
new file mode 100644
index 0000000..04d61a1
--- /dev/null
+++ b/e2fsprogs/blkid/list.c
@@ -0,0 +1,110 @@
+/* vi: set sw=4 ts=4: */
+
+#include "list.h"
+
+/*
+ * Insert a new entry between two known consecutive entries.
+ *
+ * This is only for internal list manipulation where we know
+ * the prev/next entries already!
+ */
+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.
+ */
+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.
+ */
+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!
+ */
+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.
+ */
+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.
+ */
+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.
+ */
+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.
+ */
+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;
+ }
+}