| 1 | // SPDX-FileCopyrightText: 2009 Novell Inc. |
| 2 | // SPDX-FileCopyrightText: 2010-2013 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 3 | // |
| 4 | // SPDX-License-Identifier: LGPL-2.1-only |
| 5 | |
| 6 | #ifndef _KCOMPAT_HLIST_H |
| 7 | #define _KCOMPAT_HLIST_H |
| 8 | |
| 9 | /* |
| 10 | * Kernel sourcecode compatible lightweight single pointer list head useful |
| 11 | * for implementing hash tables |
| 12 | * |
| 13 | * Author: Jan Blunck <jblunck@suse.de> |
| 14 | */ |
| 15 | |
| 16 | #include <stddef.h> |
| 17 | #include <urcu/compiler.h> |
| 18 | |
| 19 | struct cds_hlist_head { |
| 20 | struct cds_hlist_node *next; |
| 21 | }; |
| 22 | |
| 23 | struct cds_hlist_node { |
| 24 | struct cds_hlist_node *next, *prev; |
| 25 | }; |
| 26 | |
| 27 | /* Initialize a new list head. */ |
| 28 | static inline |
| 29 | void CDS_INIT_HLIST_HEAD(struct cds_hlist_head *ptr) |
| 30 | { |
| 31 | ptr->next = NULL; |
| 32 | } |
| 33 | |
| 34 | #define CDS_HLIST_HEAD(name) \ |
| 35 | struct cds_hlist_head name = { NULL } |
| 36 | |
| 37 | #define CDS_HLIST_HEAD_INIT(name) \ |
| 38 | { .next = NULL } |
| 39 | |
| 40 | /* Get typed element from list at a given position. */ |
| 41 | #define cds_hlist_entry(ptr, type, member) caa_container_of(ptr, type, member) |
| 42 | |
| 43 | /* Get typed element from list at a given position, keeping NULL pointers. */ |
| 44 | #define cds_hlist_entry_safe(ptr, type, member) \ |
| 45 | ({ \ |
| 46 | __typeof__(ptr) ____ret = (ptr); \ |
| 47 | ____ret ? cds_hlist_entry(____ret, type, member) : NULL; \ |
| 48 | }) |
| 49 | |
| 50 | /* Add new element at the head of the list. */ |
| 51 | static inline |
| 52 | void cds_hlist_add_head(struct cds_hlist_node *newp, |
| 53 | struct cds_hlist_head *head) |
| 54 | { |
| 55 | if (head->next) |
| 56 | head->next->prev = newp; |
| 57 | newp->next = head->next; |
| 58 | newp->prev = (struct cds_hlist_node *) head; |
| 59 | head->next = newp; |
| 60 | } |
| 61 | |
| 62 | /* Remove element from list. */ |
| 63 | static inline |
| 64 | void cds_hlist_del(struct cds_hlist_node *elem) |
| 65 | { |
| 66 | if (elem->next) |
| 67 | elem->next->prev = elem->prev; |
| 68 | elem->prev->next = elem->next; |
| 69 | } |
| 70 | |
| 71 | #define cds_hlist_for_each(pos, head) \ |
| 72 | for (pos = (head)->next; (pos) != NULL; pos = (pos)->next) |
| 73 | |
| 74 | #define cds_hlist_for_each_safe(pos, p, head) \ |
| 75 | for (pos = (head)->next; \ |
| 76 | ((pos) != NULL) && (p = (pos)->next, 1); \ |
| 77 | pos = (p)) |
| 78 | |
| 79 | /* |
| 80 | * cds_hlist_for_each_entry and cds_hlist_for_each_entry_safe take |
| 81 | * respectively 4 and 5 arguments, while the Linux kernel APIs take 3, |
| 82 | * and 4. We implement cds_hlist_for_each_entry_2() and |
| 83 | * cds_hlist_for_each_entry_safe_2() to follow the Linux kernel APIs. |
| 84 | */ |
| 85 | #define cds_hlist_for_each_entry(entry, pos, head, member) \ |
| 86 | for (pos = (head)->next, \ |
| 87 | entry = cds_hlist_entry(pos, __typeof__(*(entry)), member); \ |
| 88 | (pos) != NULL; \ |
| 89 | pos = (pos)->next, \ |
| 90 | entry = cds_hlist_entry(pos, __typeof__(*(entry)), member)) |
| 91 | |
| 92 | #define cds_hlist_for_each_entry_safe(entry, pos, p, head, member) \ |
| 93 | for (pos = (head)->next, \ |
| 94 | entry = cds_hlist_entry(pos, __typeof__(*(entry)), member); \ |
| 95 | ((pos) != NULL) && (p = (pos)->next, 1); \ |
| 96 | pos = (p), \ |
| 97 | entry = cds_hlist_entry(pos, __typeof__(*entry), member)) |
| 98 | |
| 99 | #define cds_hlist_for_each_entry_2(entry, head, member) \ |
| 100 | for (entry = cds_hlist_entry_safe((head)->next, __typeof__(*(entry)), member); \ |
| 101 | (entry) != NULL; \ |
| 102 | entry = cds_hlist_entry_safe((entry)->member.next, __typeof__(*(entry)), member)) |
| 103 | |
| 104 | #define cds_hlist_for_each_entry_safe_2(entry, e, head, member) \ |
| 105 | for (entry = cds_hlist_entry_safe((head)->next, __typeof__(*(entry)), member); \ |
| 106 | ((entry) != NULL) && (e = (cds_hlist_entry_safe((entry)->member.next, \ |
| 107 | __typeof__(*(entry)), member)), 1); \ |
| 108 | entry = e) |
| 109 | |
| 110 | #endif /* _KCOMPAT_HLIST_H */ |