| 1 | #ifndef _KCOMPAT_HLIST_H |
| 2 | #define _KCOMPAT_HLIST_H |
| 3 | |
| 4 | /* |
| 5 | * Kernel sourcecode compatible lightweight single pointer list head useful |
| 6 | * for implementing hash tables |
| 7 | * |
| 8 | * Copyright (C) 2009 Novell Inc. |
| 9 | * |
| 10 | * Author: Jan Blunck <jblunck@suse.de> |
| 11 | * |
| 12 | * Copyright (C) 2010 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 13 | * |
| 14 | * This program is free software; you can redistribute it and/or modify it |
| 15 | * under the terms of the GNU Lesser General Public License version 2.1 as |
| 16 | * published by the Free Software Foundation. |
| 17 | */ |
| 18 | |
| 19 | #include <stddef.h> |
| 20 | |
| 21 | struct cds_hlist_head |
| 22 | { |
| 23 | struct cds_hlist_node *next; |
| 24 | }; |
| 25 | |
| 26 | struct cds_hlist_node |
| 27 | { |
| 28 | struct cds_hlist_node *next; |
| 29 | struct cds_hlist_node *prev; |
| 30 | }; |
| 31 | |
| 32 | /* Initialize a new list head. */ |
| 33 | static inline void CDS_INIT_HLIST_HEAD(struct cds_hlist_head *ptr) |
| 34 | { |
| 35 | ptr->next = NULL; |
| 36 | } |
| 37 | |
| 38 | /* Get typed element from list at a given position. */ |
| 39 | #define cds_hlist_entry(ptr, type, member) \ |
| 40 | ((type *) ((char *) (ptr) - (unsigned long) (&((type *) 0)->member))) |
| 41 | |
| 42 | /* Add new element at the head of the list. */ |
| 43 | static inline void cds_hlist_add_head (struct cds_hlist_node *newp, |
| 44 | struct cds_hlist_head *head) |
| 45 | { |
| 46 | if (head->next) |
| 47 | head->next->prev = newp; |
| 48 | |
| 49 | newp->next = head->next; |
| 50 | newp->prev = (struct cds_hlist_node *)head; |
| 51 | head->next = newp; |
| 52 | } |
| 53 | |
| 54 | /* Remove element from list. */ |
| 55 | static inline void cds_hlist_del (struct cds_hlist_node *elem) |
| 56 | { |
| 57 | if (elem->next) |
| 58 | elem->next->prev = elem->prev; |
| 59 | |
| 60 | elem->prev->next = elem->next; |
| 61 | } |
| 62 | |
| 63 | #define cds_hlist_for_each_entry(entry, pos, head, member) \ |
| 64 | for (pos = (head)->next, \ |
| 65 | entry = cds_hlist_entry(pos, typeof(*entry), member); \ |
| 66 | pos != NULL; \ |
| 67 | pos = pos->next, \ |
| 68 | entry = cds_hlist_entry(pos, typeof(*entry), member)) |
| 69 | |
| 70 | #define cds_hlist_for_each_entry_safe(entry, pos, p, head, member) \ |
| 71 | for (pos = (head)->next, \ |
| 72 | entry = cds_hlist_entry(pos, typeof(*entry), member); \ |
| 73 | (pos != NULL) && ({ p = pos->next; 1;}); \ |
| 74 | pos = p, \ |
| 75 | entry = cds_hlist_entry(pos, typeof(*entry), member)) |
| 76 | |
| 77 | #endif /* _KCOMPAT_HLIST_H */ |