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author | Mike Gabriel <mike.gabriel@das-netzwerkteam.de> | 2017-02-09 12:32:16 +0000 |
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committer | Mike Gabriel <mike.gabriel@das-netzwerkteam.de> | 2017-03-15 11:09:41 +0100 |
commit | 289e8ce5652dda788dbed25346b3b43af70c371c (patch) | |
tree | dc69b482ae9934a92bd603b05e005d3c3f6f2385 /nx-X11/programs/Xserver/include/list.h | |
parent | 9f000842951f6b5cb40208e9254c50ec56f143e6 (diff) | |
download | nx-libs-289e8ce5652dda788dbed25346b3b43af70c371c.tar.gz nx-libs-289e8ce5652dda788dbed25346b3b43af70c371c.tar.bz2 nx-libs-289e8ce5652dda788dbed25346b3b43af70c371c.zip |
Xserver/include/list.h: Add list.h from X.org (from X.org commit 63f83d1).
Diffstat (limited to 'nx-X11/programs/Xserver/include/list.h')
-rw-r--r-- | nx-X11/programs/Xserver/include/list.h | 494 |
1 files changed, 494 insertions, 0 deletions
diff --git a/nx-X11/programs/Xserver/include/list.h b/nx-X11/programs/Xserver/include/list.h new file mode 100644 index 000000000..3f0574d43 --- /dev/null +++ b/nx-X11/programs/Xserver/include/list.h @@ -0,0 +1,494 @@ +/* + * Copyright © 2010 Intel Corporation + * Copyright © 2010 Francisco Jerez <currojerez@riseup.net> + * + * 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, sublicense, + * 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 above copyright notice and this permission notice (including the next + * paragraph) shall be included in all copies or substantial portions of the + * Software. + * + * 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 NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS 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. + * + */ + +#ifndef _XORG_LIST_H_ +#define _XORG_LIST_H_ + +#include <stddef.h> /* offsetof() */ + +/** + * @file Classic doubly-link circular list implementation. + * For real usage examples of the linked list, see the file test/list.c + * + * Example: + * We need to keep a list of struct foo in the parent struct bar, i.e. what + * we want is something like this. + * + * struct bar { + * ... + * struct foo *list_of_foos; -----> struct foo {}, struct foo {}, struct foo{} + * ... + * } + * + * We need one list head in bar and a list element in all list_of_foos (both are of + * data type 'struct xorg_list'). + * + * struct bar { + * ... + * struct xorg_list list_of_foos; + * ... + * } + * + * struct foo { + * ... + * struct xorg_list entry; + * ... + * } + * + * Now we initialize the list head: + * + * struct bar bar; + * ... + * xorg_list_init(&bar.list_of_foos); + * + * Then we create the first element and add it to this list: + * + * struct foo *foo = malloc(...); + * .... + * xorg_list_add(&foo->entry, &bar.list_of_foos); + * + * Repeat the above for each element you want to add to the list. Deleting + * works with the element itself. + * xorg_list_del(&foo->entry); + * free(foo); + * + * Note: calling xorg_list_del(&bar.list_of_foos) will set bar.list_of_foos to an empty + * list again. + * + * Looping through the list requires a 'struct foo' as iterator and the + * name of the field the subnodes use. + * + * struct foo *iterator; + * xorg_list_for_each_entry(iterator, &bar.list_of_foos, entry) { + * if (iterator->something == ...) + * ... + * } + * + * Note: You must not call xorg_list_del() on the iterator if you continue the + * loop. You need to run the safe for-each loop instead: + * + * struct foo *iterator, *next; + * xorg_list_for_each_entry_safe(iterator, next, &bar.list_of_foos, entry) { + * if (...) + * xorg_list_del(&iterator->entry); + * } + * + */ + +/** + * The linkage struct for list nodes. This struct must be part of your + * to-be-linked struct. struct xorg_list is required for both the head of the + * list and for each list node. + * + * Position and name of the struct xorg_list field is irrelevant. + * There are no requirements that elements of a list are of the same type. + * There are no requirements for a list head, any struct xorg_list can be a list + * head. + */ +struct xorg_list { + struct xorg_list *next, *prev; +}; + +/** + * Initialize the list as an empty list. + * + * Example: + * xorg_list_init(&bar->list_of_foos); + * + * @param list The list to initialize + */ +static inline void +xorg_list_init(struct xorg_list *list) +{ + list->next = list->prev = list; +} + +static inline void +__xorg_list_add(struct xorg_list *entry, + struct xorg_list *prev, struct xorg_list *next) +{ + next->prev = entry; + entry->next = next; + entry->prev = prev; + prev->next = entry; +} + +/** + * Insert a new element after the given list head. The new element does not + * need to be initialised as empty list. + * The list changes from: + * head → some element → ... + * to + * head → new element → older element → ... + * + * Example: + * struct foo *newfoo = malloc(...); + * xorg_list_add(&newfoo->entry, &bar->list_of_foos); + * + * @param entry The new element to prepend to the list. + * @param head The existing list. + */ +static inline void +xorg_list_add(struct xorg_list *entry, struct xorg_list *head) +{ + __xorg_list_add(entry, head, head->next); +} + +/** + * Append a new element to the end of the list given with this list head. + * + * The list changes from: + * head → some element → ... → lastelement + * to + * head → some element → ... → lastelement → new element + * + * Example: + * struct foo *newfoo = malloc(...); + * xorg_list_append(&newfoo->entry, &bar->list_of_foos); + * + * @param entry The new element to prepend to the list. + * @param head The existing list. + */ +static inline void +xorg_list_append(struct xorg_list *entry, struct xorg_list *head) +{ + __xorg_list_add(entry, head->prev, head); +} + +static inline void +__xorg_list_del(struct xorg_list *prev, struct xorg_list *next) +{ + next->prev = prev; + prev->next = next; +} + +/** + * Remove the element from the list it is in. Using this function will reset + * the pointers to/from this element so it is removed from the list. It does + * NOT free the element itself or manipulate it otherwise. + * + * Using xorg_list_del on a pure list head (like in the example at the top of + * this file) will NOT remove the first element from + * the list but rather reset the list as empty list. + * + * Example: + * xorg_list_del(&foo->entry); + * + * @param entry The element to remove. + */ +static inline void +xorg_list_del(struct xorg_list *entry) +{ + __xorg_list_del(entry->prev, entry->next); + xorg_list_init(entry); +} + +/** + * Check if the list is empty. + * + * Example: + * xorg_list_is_empty(&bar->list_of_foos); + * + * @return True if the list contains one or more elements or False otherwise. + */ +static inline int +xorg_list_is_empty(struct xorg_list *head) +{ + return head->next == head; +} + +/** + * Returns a pointer to the container of this list element. + * + * Example: + * struct foo* f; + * f = container_of(&foo->entry, struct foo, entry); + * assert(f == foo); + * + * @param ptr Pointer to the struct xorg_list. + * @param type Data type of the list element. + * @param member Member name of the struct xorg_list field in the list element. + * @return A pointer to the data struct containing the list head. + */ +#ifndef container_of +#define container_of(ptr, type, member) \ + (type *)((char *)(ptr) - offsetof(type, member)) +#endif + +/** + * Alias of container_of + */ +#define xorg_list_entry(ptr, type, member) \ + container_of(ptr, type, member) + +/** + * Retrieve the first list entry for the given list pointer. + * + * Example: + * struct foo *first; + * first = xorg_list_first_entry(&bar->list_of_foos, struct foo, list_of_foos); + * + * @param ptr The list head + * @param type Data type of the list element to retrieve + * @param member Member name of the struct xorg_list field in the list element. + * @return A pointer to the first list element. + */ +#define xorg_list_first_entry(ptr, type, member) \ + xorg_list_entry((ptr)->next, type, member) + +/** + * Retrieve the last list entry for the given listpointer. + * + * Example: + * struct foo *first; + * first = xorg_list_last_entry(&bar->list_of_foos, struct foo, list_of_foos); + * + * @param ptr The list head + * @param type Data type of the list element to retrieve + * @param member Member name of the struct xorg_list field in the list element. + * @return A pointer to the last list element. + */ +#define xorg_list_last_entry(ptr, type, member) \ + xorg_list_entry((ptr)->prev, type, member) + +#ifdef HAVE_TYPEOF +#define __container_of(ptr, sample, member) \ + container_of(ptr, typeof(*sample), member) +#else +/* This implementation of __container_of has undefined behavior according + * to the C standard, but it works in many cases. If your compiler doesn't + * support typeof() and fails with this implementation, please try a newer + * compiler. + */ +#define __container_of(ptr, sample, member) \ + (void *)((char *)(ptr) \ + - ((char *)&(sample)->member - (char *)(sample))) +#endif + +/** + * Loop through the list given by head and set pos to struct in the list. + * + * Example: + * struct foo *iterator; + * xorg_list_for_each_entry(iterator, &bar->list_of_foos, entry) { + * [modify iterator] + * } + * + * This macro is not safe for node deletion. Use xorg_list_for_each_entry_safe + * instead. + * + * @param pos Iterator variable of the type of the list elements. + * @param head List head + * @param member Member name of the struct xorg_list in the list elements. + * + */ +#define xorg_list_for_each_entry(pos, head, member) \ + for (pos = NULL, \ + pos = __container_of((head)->next, pos, member); \ + &pos->member != (head); \ + pos = __container_of(pos->member.next, pos, member)) + +/** + * Loop through the list, keeping a backup pointer to the element. This + * macro allows for the deletion of a list element while looping through the + * list. + * + * See xorg_list_for_each_entry for more details. + */ +#define xorg_list_for_each_entry_safe(pos, tmp, head, member) \ + for (pos = NULL, \ + pos = __container_of((head)->next, pos, member), \ + tmp = __container_of(pos->member.next, pos, member); \ + &pos->member != (head); \ + pos = tmp, tmp = __container_of(pos->member.next, tmp, member)) + +/* NULL-Terminated List Interface + * + * The interface below does _not_ use the struct xorg_list as described above. + * It is mainly for legacy structures that cannot easily be switched to + * struct xorg_list. + * + * This interface is for structs like + * struct foo { + * [...] + * struct foo *next; + * [...] + * }; + * + * The position and field name of "next" are arbitrary. + */ + +/** + * Init the element as null-terminated list. + * + * Example: + * struct foo *list = malloc(); + * nt_list_init(list, next); + * + * @param list The list element that will be the start of the list + * @param member Member name of the field pointing to next struct + */ +#define nt_list_init(_list, _member) \ + (_list)->_member = NULL + +/** + * Returns the next element in the list or NULL on termination. + * + * Example: + * struct foo *element = list; + * while ((element = nt_list_next(element, next)) { } + * + * This macro is not safe for node deletion. Use nt_list_for_each_entry_safe + * instead. + * + * @param list The list or current element. + * @param member Member name of the field pointing to next struct. + */ +#define nt_list_next(_list, _member) \ + (_list)->_member + +/** + * Iterate through each element in the list. + * + * Example: + * struct foo *iterator; + * nt_list_for_each_entry(iterator, list, next) { + * [modify iterator] + * } + * + * @param entry Assigned to the current list element + * @param list The list to iterate through. + * @param member Member name of the field pointing to next struct. + */ +#define nt_list_for_each_entry(_entry, _list, _member) \ + for (_entry = _list; _entry; _entry = (_entry)->_member) + +/** + * Iterate through each element in the list, keeping a backup pointer to the + * element. This macro allows for the deletion of a list element while + * looping through the list. + * + * See nt_list_for_each_entry for more details. + * + * @param entry Assigned to the current list element + * @param tmp The pointer to the next element + * @param list The list to iterate through. + * @param member Member name of the field pointing to next struct. + */ +#define nt_list_for_each_entry_safe(_entry, _tmp, _list, _member) \ + for (_entry = _list, _tmp = (_entry) ? (_entry)->_member : NULL;\ + _entry; \ + _entry = _tmp, _tmp = (_tmp) ? (_tmp)->_member: NULL) + +/** + * Append the element to the end of the list. This macro may be used to + * merge two lists. + * + * Example: + * struct foo *elem = malloc(...); + * nt_list_init(elem, next) + * nt_list_append(elem, list, struct foo, next); + * + * Resulting list order: + * list_item_0 -> list_item_1 -> ... -> elem_item_0 -> elem_item_1 ... + * + * @param entry An entry (or list) to append to the list + * @param list The list to append to. This list must be a valid list, not + * NULL. + * @param type The list type + * @param member Member name of the field pointing to next struct + */ +#define nt_list_append(_entry, _list, _type, _member) \ + do { \ + _type *__iterator = _list; \ + while (__iterator->_member) { __iterator = __iterator->_member;}\ + __iterator->_member = _entry; \ + } while (0) + +/** + * Insert the element at the next position in the list. This macro may be + * used to insert a list into a list. + * + * struct foo *elem = malloc(...); + * nt_list_init(elem, next) + * nt_list_insert(elem, list, struct foo, next); + * + * Resulting list order: + * list_item_0 -> elem_item_0 -> elem_item_1 ... -> list_item_1 -> ... + * + * @param entry An entry (or list) to append to the list + * @param list The list to insert to. This list must be a valid list, not + * NULL. + * @param type The list type + * @param member Member name of the field pointing to next struct + */ +#define nt_list_insert(_entry, _list, _type, _member) \ + do { \ + nt_list_append((_list)->_member, _entry, _type, _member); \ + (_list)->_member = _entry; \ + } while (0) + +/** + * Delete the entry from the list by iterating through the list and + * removing any reference from the list to the entry. + * + * Example: + * struct foo *elem = <assign to right element> + * nt_list_del(elem, list, struct foo, next); + * + * @param entry The entry to delete from the list. entry is always + * re-initialized as a null-terminated list. + * @param list The list containing the entry, set to the new list without + * the removed entry. + * @param type The list type + * @param member Member name of the field pointing to the next entry + */ +#define nt_list_del(_entry, _list, _type, _member) \ + do { \ + _type *__e = _entry; \ + if (__e == NULL || _list == NULL) break; \ + if ((_list) == __e) { \ + _list = __e->_member; \ + } else { \ + _type *__prev = _list; \ + while (__prev->_member && __prev->_member != __e) \ + __prev = nt_list_next(__prev, _member); \ + if (__prev->_member) \ + __prev->_member = __e->_member; \ + } \ + nt_list_init(__e, _member); \ + } while(0) + +/** + * DO NOT USE THIS. + * This is a remainder of the xfree86 DDX attempt of having a set of generic + * list functions. Unfortunately, the xf86OptionRec uses it and we can't + * easily get rid of it. Do not use for new code. + */ +typedef struct generic_list_rec { + void *next; +} GenericListRec, *GenericListPtr, *glp; + +#endif |