| 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) 2010-2013 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 | struct cds_hlist_node *next; |
| 23 | }; |
| 24 | |
| 25 | struct cds_hlist_node { |
| 26 | struct cds_hlist_node *next, *prev; |
| 27 | }; |
| 28 | |
| 29 | /* Initialize a new list head. */ |
| 30 | static inline |
| 31 | void CDS_INIT_HLIST_HEAD(struct cds_hlist_head *ptr) |
| 32 | { |
| 33 | ptr->next = NULL; |
| 34 | } |
| 35 | |
| 36 | #define CDS_HLIST_HEAD(name) \ |
| 37 | struct cds_hlist_head name = { NULL } |
| 38 | |
| 39 | #define CDS_HLIST_HEAD_INIT(name) \ |
| 40 | { .next = NULL } |
| 41 | |
| 42 | /* Get typed element from list at a given position. */ |
| 43 | #define cds_hlist_entry(ptr, type, member) \ |
| 44 | ((type *) ((char *) (ptr) - (unsigned long) (&((type *) 0)->member))) |
| 45 | |
| 46 | /* Add new element at the head of the list. */ |
| 47 | static inline |
| 48 | void cds_hlist_add_head(struct cds_hlist_node *newp, |
| 49 | struct cds_hlist_head *head) |
| 50 | { |
| 51 | if (head->next) |
| 52 | head->next->prev = newp; |
| 53 | newp->next = head->next; |
| 54 | newp->prev = (struct cds_hlist_node *) head; |
| 55 | head->next = newp; |
| 56 | } |
| 57 | |
| 58 | /* Remove element from list. */ |
| 59 | static inline |
| 60 | void cds_hlist_del(struct cds_hlist_node *elem) |
| 61 | { |
| 62 | if (elem->next) |
| 63 | elem->next->prev = elem->prev; |
| 64 | elem->prev->next = elem->next; |
| 65 | } |
| 66 | |
| 67 | #define cds_hlist_for_each(pos, head) \ |
| 68 | for (pos = (head)->next; pos != NULL; pos = pos->next) |
| 69 | |
| 70 | #define cds_hlist_for_each_safe(pos, p, head) \ |
| 71 | for (pos = (head)->next; \ |
| 72 | (pos != NULL) && (p = pos->next, 1); \ |
| 73 | pos = p) |
| 74 | |
| 75 | /* |
| 76 | * cds_hlist_for_each_entry and cds_hlist_for_each_entry_safe take |
| 77 | * respectively 4 and 5 arguments, while the Linux kernel APIs take 3, |
| 78 | * and 4. We implement cds_hlist_for_each_entry_2() and |
| 79 | * cds_hlist_for_each_entry_safe_2() to follow the Linux kernel APIs. |
| 80 | */ |
| 81 | #define cds_hlist_for_each_entry(entry, pos, head, member) \ |
| 82 | for (pos = (head)->next, \ |
| 83 | entry = cds_hlist_entry(pos, __typeof__(*entry), member); \ |
| 84 | pos != NULL; \ |
| 85 | pos = pos->next, \ |
| 86 | entry = cds_hlist_entry(pos, __typeof__(*entry), member)) |
| 87 | |
| 88 | #define cds_hlist_for_each_entry_safe(entry, pos, p, head, member) \ |
| 89 | for (pos = (head)->next, \ |
| 90 | entry = cds_hlist_entry(pos, __typeof__(*entry), member); \ |
| 91 | (pos != NULL) && (p = pos->next, 1); \ |
| 92 | pos = p, \ |
| 93 | entry = cds_hlist_entry(pos, __typeof__(*entry), member)) |
| 94 | |
| 95 | #define cds_hlist_for_each_entry_2(entry, head, member) \ |
| 96 | for (entry = ((head)->next == NULL ? NULL \ |
| 97 | : cds_hlist_entry((head)->next, __typeof__(*entry), member)); \ |
| 98 | entry != NULL; \ |
| 99 | entry = (entry->member.next == NULL ? NULL \ |
| 100 | : cds_hlist_entry(entry->member.next, __typeof__(*entry), member))) |
| 101 | |
| 102 | #define cds_hlist_for_each_entry_safe_2(entry, e, head, member) \ |
| 103 | for (entry = ((head)->next == NULL ? NULL \ |
| 104 | : cds_hlist_entry((head)->next, __typeof__(*entry), member)); \ |
| 105 | (entry != NULL) && (e = (entry->member.next == NULL ? NULL \ |
| 106 | : cds_hlist_entry(entry->member.next, \ |
| 107 | __typeof__(*entry), member)), 1); \ |
| 108 | entry = e) |
| 109 | |
| 110 | #endif /* _KCOMPAT_HLIST_H */ |