/include/sys/list.h
C Header | 219 lines | 143 code | 37 blank | 39 comment | 17 complexity | 109f8854e3ea8517e921322fc5c0efdb MD5 | raw file
Possible License(s): GPL-2.0
- /*****************************************************************************\
- * Copyright (C) 2007-2010 Lawrence Livermore National Security, LLC.
- * Copyright (C) 2007 The Regents of the University of California.
- * Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
- * Written by Brian Behlendorf <behlendorf1@llnl.gov>.
- * UCRL-CODE-235197
- *
- * This file is part of the SPL, Solaris Porting Layer.
- * For details, see <http://zfsonlinux.org/>.
- *
- * The SPL is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by the
- * Free Software Foundation; either version 2 of the License, or (at your
- * option) any later version.
- *
- * The SPL is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
- * for more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with the SPL. If not, see <http://www.gnu.org/licenses/>.
- \*****************************************************************************/
- #ifndef _SPL_LIST_H
- #define _SPL_LIST_H
- #include <sys/types.h>
- #include <linux/list.h>
- /*
- * NOTE: I have implemented the Solaris list API in terms of the native
- * linux API. This has certain advantages in terms of leveraging the linux
- * list debugging infrastructure, but it also means that the internals of a
- * list differ slightly than on Solaris. This is not a problem as long as
- * all callers stick to the published API. The two major differences are:
- *
- * 1) A list_node_t is mapped to a linux list_head struct which changes
- * the name of the list_next/list_prev pointers to next/prev respectively.
- *
- * 2) A list_node_t which is not attached to a list on Solaris is denoted
- * by having its list_next/list_prev pointers set to NULL. Under linux
- * the next/prev pointers are set to LIST_POISON1 and LIST_POISON2
- * respectively. At this moment this only impacts the implementation
- * of the list_link_init() and list_link_active() functions.
- */
- typedef struct list_head list_node_t;
- typedef struct list {
- size_t list_size;
- size_t list_offset;
- list_node_t list_head;
- } list_t;
- #define list_d2l(a, obj) ((list_node_t *)(((char *)obj) + (a)->list_offset))
- #define list_object(a, node) ((void *)(((char *)node) - (a)->list_offset))
- static inline int
- list_is_empty(list_t *list)
- {
- return list_empty(&list->list_head);
- }
- static inline void
- list_link_init(list_node_t *node)
- {
- node->next = LIST_POISON1;
- node->prev = LIST_POISON2;
- }
- static inline void
- list_create(list_t *list, size_t size, size_t offset)
- {
- ASSERT(list);
- ASSERT(size > 0);
- ASSERT(size >= offset + sizeof(list_node_t));
- list->list_size = size;
- list->list_offset = offset;
- INIT_LIST_HEAD(&list->list_head);
- }
- static inline void
- list_destroy(list_t *list)
- {
- ASSERT(list);
- ASSERT(list_is_empty(list));
- list_del(&list->list_head);
- }
- static inline void
- list_insert_head(list_t *list, void *object)
- {
- list_add(list_d2l(list, object), &list->list_head);
- }
- static inline void
- list_insert_tail(list_t *list, void *object)
- {
- list_add_tail(list_d2l(list, object), &list->list_head);
- }
- static inline void
- list_insert_after(list_t *list, void *object, void *nobject)
- {
- if (object == NULL)
- list_insert_head(list, nobject);
- else
- list_add(list_d2l(list, nobject), list_d2l(list, object));
- }
- static inline void
- list_insert_before(list_t *list, void *object, void *nobject)
- {
- if (object == NULL)
- list_insert_tail(list, nobject);
- else
- list_add_tail(list_d2l(list, nobject), list_d2l(list, object));
- }
- static inline void
- list_remove(list_t *list, void *object)
- {
- ASSERT(!list_is_empty(list));
- list_del(list_d2l(list, object));
- }
- static inline void *
- list_remove_head(list_t *list)
- {
- list_node_t *head = list->list_head.next;
- if (head == &list->list_head)
- return NULL;
- list_del(head);
- return list_object(list, head);
- }
- static inline void *
- list_remove_tail(list_t *list)
- {
- list_node_t *tail = list->list_head.prev;
- if (tail == &list->list_head)
- return NULL;
- list_del(tail);
- return list_object(list, tail);
- }
- static inline void *
- list_head(list_t *list)
- {
- if (list_is_empty(list))
- return NULL;
- return list_object(list, list->list_head.next);
- }
- static inline void *
- list_tail(list_t *list)
- {
- if (list_is_empty(list))
- return NULL;
- return list_object(list, list->list_head.prev);
- }
- static inline void *
- list_next(list_t *list, void *object)
- {
- list_node_t *node = list_d2l(list, object);
- if (node->next != &list->list_head)
- return list_object(list, node->next);
- return NULL;
- }
- static inline void *
- list_prev(list_t *list, void *object)
- {
- list_node_t *node = list_d2l(list, object);
- if (node->prev != &list->list_head)
- return list_object(list, node->prev);
- return NULL;
- }
- static inline int
- list_link_active(list_node_t *node)
- {
- return (node->next != LIST_POISON1) && (node->prev != LIST_POISON2);
- }
- static inline void
- spl_list_move_tail(list_t *dst, list_t *src)
- {
- list_splice_init(&src->list_head, dst->list_head.prev);
- }
- #define list_move_tail(dst, src) spl_list_move_tail(dst, src)
- static inline void
- list_link_replace(list_node_t *old_node, list_node_t *new_node)
- {
- ASSERT(list_link_active(old_node));
- ASSERT(!list_link_active(new_node));
- new_node->next = old_node->next;
- new_node->prev = old_node->prev;
- old_node->prev->next = new_node;
- old_node->next->prev = new_node;
- list_link_init(old_node);
- }
- #endif /* SPL_LIST_H */