| /************************************************************************** |
| * |
| * Copyright 2006 VMware, Inc., Bismarck, ND. USA. |
| * All Rights Reserved. |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a |
| * copy of this software and associated documentation files (the |
| * "Software"), to deal in the Software without restriction, including |
| * without limitation the rights to use, copy, modify, merge, publish, |
| * distribute, sub license, and/or sell copies of the Software, and to |
| * permit persons to whom the Software is furnished to do so, subject to |
| * the following conditions: |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL |
| * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, |
| * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR |
| * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE |
| * USE OR OTHER DEALINGS IN THE SOFTWARE. |
| * |
| * The above copyright notice and this permission notice (including the |
| * next paragraph) shall be included in all copies or substantial portions |
| * of the Software. |
| * |
| **************************************************************************/ |
| |
| /** |
| * \file |
| * List macros heavily inspired by the Linux kernel |
| * list handling. No list looping yet. |
| * |
| * Is not threadsafe, so common operations need to |
| * be protected using an external mutex. |
| */ |
| |
| #ifndef _UTIL_LIST_H_ |
| #define _UTIL_LIST_H_ |
| |
| |
| #include <stdbool.h> |
| #include <stddef.h> |
| #include <assert.h> |
| |
| #define list_assert(cond, msg) assert(cond && msg) |
| |
| struct list_head |
| { |
| struct list_head *prev; |
| struct list_head *next; |
| }; |
| |
| static inline void list_inithead(struct list_head *item) |
| { |
| item->prev = item; |
| item->next = item; |
| } |
| |
| /** |
| * Prepend an item to a list |
| * |
| * @param item The element to add to the list |
| * @param list The list to prepend to |
| */ |
| static inline void list_add(struct list_head *item, struct list_head *list) |
| { |
| item->prev = list; |
| item->next = list->next; |
| list->next->prev = item; |
| list->next = item; |
| } |
| |
| /** |
| * Append an item to a list |
| * |
| * @param item The element to add to the list |
| * @param list The list to append to |
| */ |
| static inline void list_addtail(struct list_head *item, struct list_head *list) |
| { |
| item->next = list; |
| item->prev = list->prev; |
| list->prev->next = item; |
| list->prev = item; |
| } |
| |
| static inline bool list_is_empty(const struct list_head *list); |
| |
| static inline void list_replace(struct list_head *from, struct list_head *to) |
| { |
| if (list_is_empty(from)) { |
| list_inithead(to); |
| } else { |
| to->prev = from->prev; |
| to->next = from->next; |
| from->next->prev = to; |
| from->prev->next = to; |
| } |
| } |
| |
| static inline void list_del(struct list_head *item) |
| { |
| item->prev->next = item->next; |
| item->next->prev = item->prev; |
| item->prev = item->next = NULL; |
| } |
| |
| static inline void list_delinit(struct list_head *item) |
| { |
| item->prev->next = item->next; |
| item->next->prev = item->prev; |
| item->next = item; |
| item->prev = item; |
| } |
| |
| static inline bool list_is_empty(const struct list_head *list) |
| { |
| return list->next == list; |
| } |
| |
| static inline bool list_is_linked(const struct list_head *list) |
| { |
| /* both must be NULL or both must be not NULL */ |
| assert((list->prev != NULL) == (list->next != NULL)); |
| |
| return list->next != NULL; |
| } |
| |
| /** |
| * Returns whether the list has exactly one element. |
| */ |
| static inline bool list_is_singular(const struct list_head *list) |
| { |
| return list_is_linked(list) && !list_is_empty(list) && list->next->next == list; |
| } |
| |
| static inline unsigned list_length(const struct list_head *list) |
| { |
| struct list_head *node; |
| unsigned length = 0; |
| for (node = list->next; node != list; node = node->next) |
| length++; |
| return length; |
| } |
| |
| static inline void list_splice(struct list_head *src, struct list_head *dst) |
| { |
| if (list_is_empty(src)) |
| return; |
| |
| src->next->prev = dst; |
| src->prev->next = dst->next; |
| dst->next->prev = src->prev; |
| dst->next = src->next; |
| } |
| |
| static inline void list_splicetail(struct list_head *src, struct list_head *dst) |
| { |
| if (list_is_empty(src)) |
| return; |
| |
| src->prev->next = dst; |
| src->next->prev = dst->prev; |
| dst->prev->next = src->next; |
| dst->prev = src->prev; |
| } |
| |
| static inline void list_validate(const struct list_head *list) |
| { |
| struct list_head *node; |
| assert(list_is_linked(list)); |
| assert(list->next->prev == list && list->prev->next == list); |
| for (node = list->next; node != list; node = node->next) |
| assert(node->next->prev == node && node->prev->next == node); |
| } |
| |
| /** |
| * Move an item from one place in a list to another |
| * |
| * The item can be in this list, or in another. |
| * |
| * @param item The item to move |
| * @param loc The element to put the item in front of |
| */ |
| static inline void list_move_to(struct list_head *item, struct list_head *loc) { |
| list_del(item); |
| list_add(item, loc); |
| } |
| |
| #define list_entry(__item, __type, __field) \ |
| ((__type *)(((char *)(__item)) - offsetof(__type, __field))) |
| |
| /** |
| * Cast from a pointer to a member of a struct back to the containing struct. |
| * |
| * 'sample' MUST be initialized, or else the result is undefined! |
| */ |
| #define list_container_of(ptr, sample, member) \ |
| (void *)((char *)(ptr) \ |
| - ((char *)&(sample)->member - (char *)(sample))) |
| |
| #define list_first_entry(ptr, type, member) \ |
| list_entry((ptr)->next, type, member) |
| |
| #define list_last_entry(ptr, type, member) \ |
| list_entry((ptr)->prev, type, member) |
| |
| |
| #define LIST_FOR_EACH_ENTRY(pos, head, member) \ |
| for (pos = NULL, pos = list_container_of((head)->next, pos, member); \ |
| &pos->member != (head); \ |
| pos = list_container_of(pos->member.next, pos, member)) |
| |
| #define LIST_FOR_EACH_ENTRY_SAFE(pos, storage, head, member) \ |
| for (pos = NULL, pos = list_container_of((head)->next, pos, member), \ |
| storage = list_container_of(pos->member.next, pos, member); \ |
| &pos->member != (head); \ |
| pos = storage, storage = list_container_of(storage->member.next, storage, member)) |
| |
| #define LIST_FOR_EACH_ENTRY_SAFE_REV(pos, storage, head, member) \ |
| for (pos = NULL, pos = list_container_of((head)->prev, pos, member), \ |
| storage = list_container_of(pos->member.prev, pos, member); \ |
| &pos->member != (head); \ |
| pos = storage, storage = list_container_of(storage->member.prev, storage, member)) |
| |
| #define LIST_FOR_EACH_ENTRY_FROM(pos, start, head, member) \ |
| for (pos = NULL, pos = list_container_of((start), pos, member); \ |
| &pos->member != (head); \ |
| pos = list_container_of(pos->member.next, pos, member)) |
| |
| #define LIST_FOR_EACH_ENTRY_FROM_REV(pos, start, head, member) \ |
| for (pos = NULL, pos = list_container_of((start), pos, member); \ |
| &pos->member != (head); \ |
| pos = list_container_of(pos->member.prev, pos, member)) |
| |
| #define list_for_each_entry(type, pos, head, member) \ |
| for (type *pos = list_entry((head)->next, type, member), \ |
| *__next = list_entry(pos->member.next, type, member); \ |
| &pos->member != (head); \ |
| pos = list_entry(pos->member.next, type, member), \ |
| list_assert(pos == __next, "use _safe iterator"), \ |
| __next = list_entry(__next->member.next, type, member)) |
| |
| #define list_for_each_entry_safe(type, pos, head, member) \ |
| for (type *pos = list_entry((head)->next, type, member), \ |
| *__next = list_entry(pos->member.next, type, member); \ |
| &pos->member != (head); \ |
| pos = __next, \ |
| __next = list_entry(__next->member.next, type, member)) |
| |
| #define list_for_each_entry_rev(type, pos, head, member) \ |
| for (type *pos = list_entry((head)->prev, type, member), \ |
| *__prev = list_entry(pos->member.prev, type, member); \ |
| &pos->member != (head); \ |
| pos = list_entry(pos->member.prev, type, member), \ |
| list_assert(pos == __prev, "use _safe iterator"), \ |
| __prev = list_entry(__prev->member.prev, type, member)) |
| |
| #define list_for_each_entry_safe_rev(type, pos, head, member) \ |
| for (type *pos = list_entry((head)->prev, type, member), \ |
| *__prev = list_entry(pos->member.prev, type, member); \ |
| &pos->member != (head); \ |
| pos = __prev, \ |
| __prev = list_entry(__prev->member.prev, type, member)) |
| |
| #define list_for_each_entry_from(type, pos, start, head, member) \ |
| for (type *pos = list_entry((start), type, member); \ |
| &pos->member != (head); \ |
| pos = list_entry(pos->member.next, type, member)) |
| |
| #define list_for_each_entry_from_safe(type, pos, start, head, member) \ |
| for (type *pos = list_entry((start), type, member), \ |
| *__next = list_entry(pos->member.next, type, member); \ |
| &pos->member != (head); \ |
| pos = __next, \ |
| __next = list_entry(__next->member.next, type, member)) |
| |
| #define list_for_each_entry_from_rev(type, pos, start, head, member) \ |
| for (type *pos = list_entry((start), type, member); \ |
| &pos->member != (head); \ |
| pos = list_entry(pos->member.prev, type, member)) |
| |
| #define list_pair_for_each_entry(type, pos1, pos2, head1, head2, member) \ |
| for (type *pos1 = list_entry((head1)->next, type, member), \ |
| *pos2 = list_entry((head2)->next, type, member); \ |
| &pos1->member != (head1) && &pos2->member != (head2); \ |
| pos1 = list_entry(pos1->member.next, type, member), \ |
| pos2 = list_entry(pos2->member.next, type, member)) |
| |
| #endif /*_UTIL_LIST_H_*/ |