2 * Copyright (C) 1995-2008 University of Karlsruhe. All right reserved.
4 * This file is part of libFirm.
6 * This file may be distributed and/or modified under the terms of the
7 * GNU General Public License version 2 as published by the Free Software
8 * Foundation and appearing in the file LICENSE.GPL included in the
9 * packaging of this file.
11 * Licensees holding valid libFirm Professional Edition licenses may use
12 * this file in accordance with the libFirm Commercial License.
13 * Agreement provided with the Software.
15 * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
16 * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23 * @author Christian Wuerdig
24 * @brief Implementation of a priority queue. This is the ported version of
25 the original Java implementation by Matthias Braun.
28 #ifndef FIRM_ADT_PQUEUE_H
29 #define FIRM_ADT_PQUEUE_H
33 typedef struct _pqueue_t pqueue_t;
36 * Creates a new priority queue.
37 * @return A priority queue of initial length 0.
39 FIRM_API pqueue_t *new_pqueue(void);
42 * Frees all memory allocated by the priority queue.
43 * @param q The priority queue to destroy.
45 FIRM_API void del_pqueue(pqueue_t *q);
48 * Inserts a new element into a priority queue.
49 * @param q The priority queue the element should be inserted to.
50 * @param data The actual data which should be stored in the queue.
51 * @param priority The priority for the data.
53 FIRM_API void pqueue_put(pqueue_t *q, void *data, int priority);
56 * Returns and removes the first element, ie. that one with the highest priority, from the queue.
57 * @param q The priority queue.
58 * @return The first element of the queue. Asserts if queue is empty.
60 FIRM_API void *pqueue_pop_front(pqueue_t *q);
63 * Get the length of the priority queue.
64 * @param q The priority queue.
65 * @return The length of the queue.
67 FIRM_API int pqueue_length(const pqueue_t *q);
70 * Returns true if queue is empty.
71 * @param q The priority queue.
72 * @return 1 if the queue is empty, 0 otherwise.
74 FIRM_API int pqueue_empty(const pqueue_t *q);