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Diffstat (limited to 'src/common/lists.h')
-rw-r--r-- | src/common/lists.h | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/src/common/lists.h b/src/common/lists.h new file mode 100644 index 0000000..972ea49 --- /dev/null +++ b/src/common/lists.h @@ -0,0 +1,103 @@ +/* Copyright (C) 2011 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz> + + 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/>. + */ +/* + * BIRD Library -- Linked Lists + * + * (c) 1998 Martin Mares <mj@ucw.cz> + * + * Can be freely distributed and used under the terms of the GNU GPL. + */ + +#ifndef _BIRD_LISTS_H_ +#define _BIRD_LISTS_H_ + +/* + * I admit the list structure is very tricky and also somewhat awkward, + * but it's both efficient and easy to manipulate once one understands the + * basic trick: The list head always contains two synthetic nodes which are + * always present in the list: the head and the tail. But as the `next' + * entry of the tail and the `prev' entry of the head are both NULL, the + * nodes can overlap each other: + * + * head head_node.next + * null head_node.prev tail_node.next + * tail tail_node.prev + */ + +#include <string.h> // size_t + +typedef struct node { + struct node *next, *prev; +} node; + +typedef struct list { /* In fact two overlayed nodes */ + struct node *head, *null, *tail; +} list; + +#define NODE (node *) +#define HEAD(list) ((void *)((list).head)) +#define TAIL(list) ((void *)((list).tail)) +#define WALK_LIST(n,list) for(n=HEAD(list);(NODE (n))->next; \ + n=(void *)((NODE (n))->next)) +#define WALK_LIST_DELSAFE(n,nxt,list) \ + for(n=HEAD(list); (nxt=(void *)((NODE (n))->next)); n=(void *) nxt) +/* WALK_LIST_FIRST supposes that called code removes each processed node */ +#define WALK_LIST_FIRST(n,list) \ + while(n=HEAD(list), (NODE (n))->next) +#define WALK_LIST_BACKWARDS(n,list) for(n=TAIL(list);(NODE (n))->prev; \ + n=(void *)((NODE (n))->prev)) +#define WALK_LIST_BACKWARDS_DELSAFE(n,prv,list) \ + for(n=TAIL(list); prv=(void *)((NODE (n))->prev); n=(void *) prv) + +#define EMPTY_LIST(list) (!(list).head->next) + +/*! \brief Free every node in the list. */ +#define WALK_LIST_FREE(list) \ + do { \ + node *n=0,*nxt=0; \ + WALK_LIST_DELSAFE(n,nxt,list) { \ + free(n); \ + } \ + } while(0) + +void add_tail(list *, node *); +void add_head(list *, node *); +void rem_node(node *); +void add_tail_list(list *, list *); +void init_list(list *); +void insert_node(node *, node *); +void list_dup(list *dst, list *src, size_t itemsz); + +/*! + * \brief List item for string lists. + */ +typedef struct strnode_t { + node n; + char *str; +} strnode_t; + +/*! \todo This is broken atm. +#ifndef _BIRD_LISTS_C_ +#define LIST_INLINE extern inline +#include "knot/lib/lists.c" +#undef LIST_INLINE +#else +#define LIST_INLINE +#endif +*/ +#define LIST_INLINE + +#endif |