/* SPDX-License-Identifier: LGPL-2.1-or-later */
#pragma once
#include "macro.h"
/* The head of the linked list. Use this in the structure that shall
* contain the head of the linked list */
#define LIST_HEAD(t,name) \
t *name
/* The pointers in the linked list's items. Use this in the item structure */
#define LIST_FIELDS(t,name) \
t *name##_next, *name##_prev
/* Initialize the list's head */
#define LIST_HEAD_INIT(head) \
do { \
(head) = NULL; \
} while (false)
/* Initialize a list item */
#define LIST_INIT(name,item) \
do { \
typeof(*(item)) *_item = (item); \
assert(_item); \
_item->name##_prev = _item->name##_next = NULL; \
} while (false)
/* Prepend an item to the list */
#define LIST_PREPEND(name,head,item) \
do { \
typeof(*(head)) **_head = &(head), *_item = (item); \
assert(_item); \
if ((_item->name##_next = *_head)) \
_item->name##_next->name##_prev = _item; \
_item->name##_prev = NULL; \
*_head = _item; \
} while (false)
/* Append an item to the list */
#define LIST_APPEND(name,head,item) \
do { \
typeof(*(head)) **_hhead = &(head), *_tail; \
LIST_FIND_TAIL(name, *_hhead, _tail); \
LIST_INSERT_AFTER(name, *_hhead, _tail, item); \
} while (false)
/* Remove an item from the list */
#define LIST_REMOVE(name,head,item) \
do { \
typeof(*(head)) **_head = &(head), *_item = (item); \
assert(_item); \
if (_item->name##_next) \
_item->name##_next->name##_prev = _item->name##_prev; \
if (_item->name##_prev) \
_item->name##_prev->name##_next = _item->name##_next; \
else { \
assert(*_head == _item); \
*_head = _item->name##_next; \
} \
_item->name##_next = _item->name##_prev = NULL; \
} while (false)
/* Find the head of the list */
#define LIST_FIND_HEAD(name,item,head) \
do { \
typeof(*(item)) *_item = (item); \
if (!_item) \
(head) = NULL; \
else { \
while (_item->name##_prev) \
_item = _item->name##_prev; \
(head) = _item; \
} \
} while (false)
/* Find the tail of the list */
#define LIST_FIND_TAIL(name,item,tail) \
do { \
typeof(*(item)) *_item = (item); \
if (!_item) \
(tail) = NULL; \
else { \
while (_item->name##_next) \
_item = _item->name##_next; \
(tail) = _item; \
} \
} while (false)
/* Insert an item after another one (a = where, b = what) */
#define LIST_INSERT_AFTER(name,head,a,b) \
do { \
typeof(*(head)) **_head = &(head), *_a = (a), *_b = (b); \
assert(_b); \
if (!_a) { \
if ((_b->name##_next = *_head)) \
_b->name##_next->name##_prev = _b; \
_b->name##_prev = NULL; \
*_head = _b; \
} else { \
if ((_b->name##_next = _a->name##_next)) \
_b->name##_next->name##_prev = _b; \
_b->name##_prev = _a; \
_a->name##_next = _b; \
} \
} while (false)
/* Insert an item before another one (a = where, b = what) */
#define LIST_INSERT_BEFORE(name,head,a,b) \
do { \
typeof(*(head)) **_head = &(head), *_a = (a), *_b = (b); \
assert(_b); \
if (!_a) { \
if (!*_head) { \
_b->name##_next = NULL; \
_b->name##_prev = NULL; \
*_head = _b; \
} else { \
typeof(*(head)) *_tail = (head); \
while (_tail->name##_next) \
_tail = _tail->name##_next; \
_b->name##_next = NULL; \
_b->name##_prev = _tail; \
_tail->name##_next = _b; \
} \
} else { \
if ((_b->name##_prev = _a->name##_prev)) \
_b->name##_prev->name##_next = _b; \
else \
*_head = _b; \
_b->name##_next = _a; \
_a->name##_prev = _b; \
} \
} while (false)
#define LIST_JUST_US(name,item) \
(!(item)->name##_prev && !(item)->name##_next) \
#define LIST_FOREACH(name,i,head) \
for ((i) = (head); (i); (i) = (i)->name##_next)
#define LIST_FOREACH_SAFE(name,i,n,head) \
for ((i) = (head); (i) && (((n) = (i)->name##_next), 1); (i) = (n))
#define LIST_FOREACH_BEFORE(name,i,p) \
for ((i) = (p)->name##_prev; (i); (i) = (i)->name##_prev)
#define LIST_FOREACH_AFTER(name,i,p) \
for ((i) = (p)->name##_next; (i); (i) = (i)->name##_next)
/* Iterate through all the members of the list p is included in, but skip over p */
#define LIST_FOREACH_OTHERS(name,i,p) \
for (({ \
(i) = (p); \
while ((i) && (i)->name##_prev) \
(i) = (i)->name##_prev; \
if ((i) == (p)) \
(i) = (p)->name##_next; \
}); \
(i); \
(i) = (i)->name##_next == (p) ? (p)->name##_next : (i)->name##_next)
/* Loop starting from p->next until p->prev.
p can be adjusted meanwhile. */
#define LIST_LOOP_BUT_ONE(name,i,head,p) \
for ((i) = (p)->name##_next ? (p)->name##_next : (head); \
(i) != (p); \
(i) = (i)->name##_next ? (i)->name##_next : (head))
#define LIST_IS_EMPTY(head) \
(!(head))
/* Join two lists tail to head: a->b, c->d to a->b->c->d and de-initialise second list */
#define LIST_JOIN(name,a,b) \
do { \
assert(b); \
if (!(a)) \
(a) = (b); \
else { \
typeof(*(a)) *_head = (b), *_tail; \
LIST_FIND_TAIL(name, (a), _tail); \
_tail->name##_next = _head; \
_head->name##_prev = _tail; \
} \
(b) = NULL; \
} while (false)