4 * Copyright 2003, 2004 Develer S.r.l. (http://www.develer.com/)
5 * Copyright 2001 Bernardo Innocenti <bernie@develer.com>
6 * This file is part of DevLib - See README.devlib for information.
11 * \author Bernardo Innocenti <bernie@develer.com>
13 * \brief General pourpose double-linked lists
18 *#* Revision 1.17 2006/02/24 01:18:34 bernie
19 *#* LIST_ENQUEUE(): New macro; Remove obsolete names.
21 *#* Revision 1.16 2006/01/23 23:10:38 bernie
22 *#* REVERSE_FOREACH_NODE(): New macro; FOREACHNODE(): Rename to FOREACH_NODE.
24 *#* Revision 1.15 2005/11/04 16:20:02 bernie
25 *#* Fix reference to README.devlib in header.
27 *#* Revision 1.14 2005/07/19 07:25:18 bernie
28 *#* Refactor to remove type aliasing problems.
30 *#* Revision 1.13 2005/04/11 19:10:28 bernie
31 *#* Include top-level headers from cfg/ subdir.
33 *#* Revision 1.12 2005/01/22 04:21:32 bernie
34 *#* Add integrity checks.
36 *#* Revision 1.11 2004/12/31 16:44:11 bernie
37 *#* list_remHead(), list_remTail(): Name like normal functions.
39 *#* Revision 1.10 2004/11/28 23:21:05 bernie
40 *#* Remove obsolete INITLIST macro.
42 *#* Revision 1.9 2004/10/21 09:37:55 bernie
43 *#* Revamp documentation.
45 *#* Revision 1.8 2004/10/19 08:46:34 bernie
48 *#* Revision 1.7 2004/08/25 14:12:09 rasky
49 *#* Aggiornato il comment block dei log RCS
51 *#* Revision 1.6 2004/07/30 14:34:10 rasky
52 *#* Vari fix per documentazione e commenti
53 *#* Aggiunte PP_CATn e STATIC_ASSERT
55 *#* Revision 1.5 2004/07/20 23:45:01 bernie
56 *#* Finally remove redundant protos.
58 *#* Revision 1.4 2004/07/18 22:12:53 bernie
59 *#* Fix warnings with GCC 3.3.2.
61 *#* Revision 1.3 2004/07/18 22:01:43 bernie
62 *#* REMHEAD(), REMTAIL(): Move to list.h as inline functions.
64 *#* Revision 1.2 2004/06/03 11:27:09 bernie
65 *#* Add dual-license information.
67 *#* Revision 1.1 2004/05/23 15:43:16 bernie
68 *#* Import mware modules.
74 #include <cfg/compiler.h> /* INLINE */
75 #include <cfg/debug.h> /* ASSERT() */
78 * This structure represents a node for bidirectional lists.
80 * Data is usually appended to nodes by making them the first
81 * field of another struture, as a poor-man's form of inheritance.
90 * Head of a doubly-linked list of \c Node structs.
92 * Lists must be initialized with LIST_INIT() prior to use.
94 * Nodes can be added and removed from either end of the list
95 * with O(1) performance. Iterating over these lists can be
96 * tricky: use the FOREACH_NODE() macro instead.
105 * Extended node for priority queues.
107 typedef struct _PriNode
115 * Template for a naked node in a list of \a T structures.
117 * To be used as data member in other structures:
122 * DECLARE_NODE_ANON(struct Foo)
127 * DECLARE_LIST_TYPE(Foo);
131 * static LIST_TYPE(Foo) foo_list;
132 * static Foo foo1, foo2;
135 * LIST_INIT(&foo_list);
136 * ADDHEAD(&foo_list, &foo1);
137 * INSERTBEFORE(&foo_list, &foo2);
138 * FOREACH_NODE(fp, &foo_list)
144 #define DECLARE_NODE_ANON(T) \
147 /*! Declare a typesafe node for structures of type \a T. */
148 #define DECLARE_NODE_TYPE(T) \
149 typedef struct T##Node { T *succ; T *pred; } T##Node
151 /*! Template for a list of \a T structures. */
152 #define DECLARE_LIST_TYPE(T) \
153 DECLARE_NODE_TYPE(T); \
154 typedef struct T##List { \
159 #define NODE_TYPE(T) T##Node
160 #define LIST_TYPE(T) T##List
163 * Get a pointer to the first node in a list.
165 * If \a l is empty, result points to l->tail.
167 #define LIST_HEAD(l) ((l)->head.succ)
170 * Get a pointer to the last node in a list.
172 * If \a l is empty, result points to l->head.
174 #define LIST_TAIL(l) ((l)->tail.pred)
177 * Iterate over all nodes in a list.
179 * This macro generates a "for" statement using the following parameters:
180 * \param n Node pointer to be used in each iteration.
181 * \param l Pointer to list.
183 #define FOREACH_NODE(n, l) \
185 (n) = (typeof(n))LIST_HEAD(l); \
186 ((Node *)(n))->succ; \
187 (n) = (typeof(n))(((Node *)(n))->succ) \
191 * Iterate backwards over all nodes in a list.
193 * This macro generates a "for" statement using the following parameters:
194 * \param n Node pointer to be used in each iteration.
195 * \param l Pointer to list.
197 #define REVERSE_FOREACH_NODE(n, l) \
199 (n) = (typeof(n))LIST_TAIL(l); \
200 ((Node *)(n))->pred; \
201 (n) = (typeof(n))(((Node *)(n))->pred) \
204 /*! Initialize a list. */
205 #define LIST_INIT(l) \
207 (l)->head.succ = (typeof((l)->head.succ)) &(l)->tail; \
208 (l)->head.pred = NULL; \
209 (l)->tail.succ = NULL; \
210 (l)->tail.pred = (typeof((l)->tail.pred)) &(l)->head; \
214 /*! Make sure that a list is valid (it was initialized and is not corrupted). */
215 #define LIST_ASSERT_VALID(l) \
218 ASSERT((l)->head.succ != NULL); \
219 ASSERT((l)->head.pred == NULL); \
220 ASSERT((l)->tail.succ == NULL); \
221 ASSERT((l)->tail.pred != NULL); \
225 ASSERT(n->pred == pred); \
228 ASSERT(n == &(l)->tail); \
231 #define INVALIDATE_NODE(n) ((n)->succ = (n)->pred = NULL)
233 #define LIST_ASSERT_VALID(l) do {} while (0)
234 #define INVALIDATE_NODE(n) do {} while (0)
237 /*! Add node to list head. */
238 #define ADDHEAD(l,n) \
242 (n)->succ = (l)->head.succ; \
243 (n)->pred = (l)->head.succ->pred; \
244 (n)->succ->pred = (n); \
245 (n)->pred->succ = (n); \
248 /*! Add node to list tail. */
249 #define ADDTAIL(l,n) \
253 (n)->succ = &(l)->tail; \
254 (n)->pred = (l)->tail.pred; \
255 (n)->pred->succ = (n); \
256 (l)->tail.pred = (n); \
260 * Insert node \a n before node \a ln.
262 * \note You can't pass in a list header as \a ln, but
263 * it is safe to pass list-\>head of an empty list.
265 #define INSERT_BEFORE(n,ln) \
268 (n)->pred = (ln)->pred; \
269 (ln)->pred->succ = (n); \
274 * Remove \a n from whatever list it is in.
276 * \note Removing a node that has not previously been
277 * inserted into a list invokes undefined behavior.
281 (n)->pred->succ = (n)->succ; \
282 (n)->succ->pred = (n)->pred; \
283 INVALIDATE_NODE(n); \
286 /*! Tell whether a list is empty. */
287 #define LIST_EMPTY(l) ( (void *)((l)->head.succ) == (void *)(&(l)->tail) )
290 * Insert a priority node in a priority queue.
292 * The new node is inserted immediately before the
293 * first node with lower priority or appended to
294 * the tail if no such node exists.
296 #define LIST_ENQUEUE(list, node) \
299 FOREACH_NODE(ln, (list)) \
300 if (ln->pri < (node)->pri) \
302 INSERT_BEFORE(&(node)->link, &ln->link); \
307 * Unlink a node from the head of the list \a l.
309 * \return Pointer to node, or NULL if the list was empty.
311 INLINE Node *list_remHead(List *l)
318 n = l->head.succ; /* Get first node. */
319 l->head.succ = n->succ; /* Link list head to second node. */
320 n->succ->pred = &l->head; /* Link second node to list head. */
327 * Unlink a node from the tail of the list \a l.
329 * \return Pointer to node, or NULL if the list was empty.
331 INLINE Node *list_remTail(List *l)
338 n = l->tail.pred; /* Get last node. */
339 l->tail.pred = n->pred; /* Link list tail to second last node. */
340 n->pred->succ = &l->tail; /* Link second last node to list tail. */
346 #endif /* MWARE_LIST_H */