/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ #pragma once /*** This file is part of systemd. Copyright 2010 Lennart Poettering systemd is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. systemd is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with systemd; If not, see <http://www.gnu.org/licenses/>. ***/ /* 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(t,head) \ do { \ (head) = NULL; } \ while(false) /* Initialize a list item */ #define LIST_INIT(t,name,item) \ do { \ t *_item = (item); \ assert(_item); \ _item->name##_prev = _item->name##_next = NULL; \ } while(false) /* Prepend an item to the list */ #define LIST_PREPEND(t,name,head,item) \ do { \ t **_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) /* Remove an item from the list */ #define LIST_REMOVE(t,name,head,item) \ do { \ t **_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(t,name,item,head) \ do { \ t *_item = (item); \ assert(_item); \ while (_item->name##_prev) \ _item = _item->name##_prev; \ (head) = _item; \ } while (false) /* Find the head of the list */ #define LIST_FIND_TAIL(t,name,item,tail) \ do { \ t *_item = (item); \ assert(_item); \ 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(t,name,head,a,b) \ do { \ t **_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) #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)