/* Unix SMB/CIFS implementation. some simple double linked list macros Copyright (C) Andrew Tridgell 1998 This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. This program 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 General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see <http://www.gnu.org/licenses/>. */ /* To use these macros you must have a structure containing a next and prev pointer */ #ifndef _DLINKLIST_H #define _DLINKLIST_H /* hook into the front of the list */ #define DLIST_ADD(list, p) \ do { \ if (!(list)) { \ (list) = (p); \ (p)->next = (p)->prev = NULL; \ } else { \ (list)->prev = (p); \ (p)->next = (list); \ (p)->prev = NULL; \ (list) = (p); \ }\ } while (0) /* remove an element from a list - element doesn't have to be in list. */ #define DLIST_REMOVE(list, p) \ do { \ if ((p) == (list)) { \ (list) = (p)->next; \ if (list) (list)->prev = NULL; \ } else { \ if ((p)->prev) (p)->prev->next = (p)->next; \ if ((p)->next) (p)->next->prev = (p)->prev; \ } \ if ((p) != (list)) (p)->next = (p)->prev = NULL; \ } while (0) /* promote an element to the top of the list */ #define DLIST_PROMOTE(list, p) \ do { \ DLIST_REMOVE(list, p); \ DLIST_ADD(list, p); \ } while (0) /* hook into the end of the list - needs the entry type */ #define DLIST_ADD_END(list, p, type) \ do { \ if (!(list)) { \ (list) = (p); \ (p)->next = (p)->prev = NULL; \ } else { \ type tmp; \ for (tmp = (list); tmp->next; tmp = tmp->next) ; \ tmp->next = (p); \ (p)->next = NULL; \ (p)->prev = tmp; \ } \ } while (0) /* insert 'p' after the given element 'el' in a list. If el is NULL then this is the same as a DLIST_ADD() */ #define DLIST_ADD_AFTER(list, p, el) \ do { \ if (!(list) || !(el)) { \ DLIST_ADD(list, p); \ } else { \ p->prev = el; \ p->next = el->next; \ el->next = p; \ if (p->next) p->next->prev = p; \ }\ } while (0) /* demote an element to the end of the list, needs the entry type */ #define DLIST_DEMOTE(list, p, type) \ do { \ DLIST_REMOVE(list, p); \ DLIST_ADD_END(list, p, type); \ } while (0) /* concatenate two lists - putting all elements of the 2nd list at the end of the first list */ #define DLIST_CONCATENATE(list1, list2, type) \ do { \ if (!(list1)) { \ (list1) = (list2); \ } else { \ type tmp; \ for (tmp = (list1); tmp->next; tmp = tmp->next) ; \ tmp->next = (list2); \ if (list2) { \ (list2)->prev = tmp; \ } \ } \ } while (0) #endif /* _DLINKLIST_H */