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author | Mike Frysinger | 2005-05-09 22:10:42 +0000 |
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committer | Mike Frysinger | 2005-05-09 22:10:42 +0000 |
commit | 1fd98e039d146dcff02a5350f509cabca65fd29c (patch) | |
tree | 1564707d41a6271bb44cf3fa5b88b9cc70fedd35 /e2fsprogs/ext2fs/kernel-list.h | |
parent | b32011943a0764872ca1ea17f13b53176ace8e69 (diff) | |
download | busybox-1fd98e039d146dcff02a5350f509cabca65fd29c.zip busybox-1fd98e039d146dcff02a5350f509cabca65fd29c.tar.gz |
import ext2fs lib to prep for new e2fsprogs
Diffstat (limited to 'e2fsprogs/ext2fs/kernel-list.h')
-rw-r--r-- | e2fsprogs/ext2fs/kernel-list.h | 112 |
1 files changed, 112 insertions, 0 deletions
diff --git a/e2fsprogs/ext2fs/kernel-list.h b/e2fsprogs/ext2fs/kernel-list.h new file mode 100644 index 0000000..24e6ab4 --- /dev/null +++ b/e2fsprogs/ext2fs/kernel-list.h @@ -0,0 +1,112 @@ +#ifndef _LINUX_LIST_H +#define _LINUX_LIST_H + +/* + * 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 LIST_HEAD(name) \ + struct list_head name = { &name, &name } + +#define INIT_LIST_HEAD(ptr) do { \ + (ptr)->next = (ptr); (ptr)->prev = (ptr); \ +} while (0) + +#if (!defined(__GNUC__) && !defined(__WATCOMC__)) +#define __inline__ +#endif + +/* + * Insert a new entry between two known consecutive entries. + * + * This is only for internal list manipulation where we know + * the prev/next entries already! + */ +static __inline__ void __list_add(struct list_head * new, + struct list_head * prev, + struct list_head * next) +{ + next->prev = new; + new->next = next; + new->prev = prev; + prev->next = new; +} + +/* + * Insert a new entry after the specified head.. + */ +static __inline__ void list_add(struct list_head *new, struct list_head *head) +{ + __list_add(new, head, head->next); +} + +/* + * Insert a new entry at the tail + */ +static __inline__ void list_add_tail(struct list_head *new, struct list_head *head) +{ + __list_add(new, 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! + */ +static __inline__ void __list_del(struct list_head * prev, + struct list_head * next) +{ + next->prev = prev; + prev->next = next; +} + +static __inline__ void list_del(struct list_head *entry) +{ + __list_del(entry->prev, entry->next); +} + +static __inline__ int list_empty(struct list_head *head) +{ + return head->next == head; +} + +/* + * Splice in "list" into "head" + */ +static __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; + } +} + +#define list_entry(ptr, type, member) \ + ((type *)((char *)(ptr)-(unsigned long)(&((type *)0)->member))) + +#define list_for_each(pos, head) \ + for (pos = (head)->next; pos != (head); pos = pos->next) + +#endif |