+++ /dev/null
-/* Priority queue functions.
- * Copyright (C) 2003 Yasuhiro Ohara
- *
- * This file is part of GNU Zebra.
- *
- * GNU Zebra 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 2, or (at your
- * option) any later version.
- *
- * GNU Zebra 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; see the file COPYING; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#include <zebra.h>
-
-#include "memory.h"
-#include "pqueue.h"
-
-DEFINE_MTYPE_STATIC(LIB, PQUEUE, "Priority queue")
-DEFINE_MTYPE_STATIC(LIB, PQUEUE_DATA, "Priority queue data")
-
-/* priority queue using heap sort */
-
-/* pqueue->cmp() controls the order of sorting (i.e, ascending or
- descending). If you want the left node to move upper of the heap
- binary tree, make cmp() to return less than 0. for example, if cmp
- (10, 20) returns -1, the sorting is ascending order. if cmp (10,
- 20) returns 1, the sorting is descending order. if cmp (10, 20)
- returns 0, this library does not do sorting (which will not be what
- you want). To be brief, if the contents of cmp_func (left, right)
- is left - right, dequeue () returns the smallest node. Otherwise
- (if the contents is right - left), dequeue () returns the largest
- node. */
-
-#define DATA_SIZE (sizeof (void *))
-#define PARENT_OF(x) ((x - 1) / 2)
-#define LEFT_OF(x) (2 * x + 1)
-#define RIGHT_OF(x) (2 * x + 2)
-#define HAVE_CHILD(x,q) (x < (q)->size / 2)
-
-void trickle_up(int index, struct pqueue *queue)
-{
- void *tmp;
-
- /* Save current node as tmp node. */
- tmp = queue->array[index];
-
- /* Continue until the node reaches top or the place where the parent
- node should be upper than the tmp node. */
- while (index > 0
- && (*queue->cmp)(tmp, queue->array[PARENT_OF(index)]) < 0) {
- /* actually trickle up */
- queue->array[index] = queue->array[PARENT_OF(index)];
- if (queue->update != NULL)
- (*queue->update)(queue->array[index], index);
- index = PARENT_OF(index);
- }
-
- /* Restore the tmp node to appropriate place. */
- queue->array[index] = tmp;
- if (queue->update != NULL)
- (*queue->update)(tmp, index);
-}
-
-void trickle_down(int index, struct pqueue *queue)
-{
- void *tmp;
- int which;
-
- /* Save current node as tmp node. */
- tmp = queue->array[index];
-
- /* Continue until the node have at least one (left) child. */
- while (HAVE_CHILD(index, queue)) {
- /* If right child exists, and if the right child is more proper
- to be moved upper. */
- if (RIGHT_OF(index) < queue->size
- && (*queue->cmp)(queue->array[LEFT_OF(index)],
- queue->array[RIGHT_OF(index)])
- > 0)
- which = RIGHT_OF(index);
- else
- which = LEFT_OF(index);
-
- /* If the tmp node should be upper than the child, break. */
- if ((*queue->cmp)(queue->array[which], tmp) > 0)
- break;
-
- /* Actually trickle down the tmp node. */
- queue->array[index] = queue->array[which];
- if (queue->update != NULL)
- (*queue->update)(queue->array[index], index);
- index = which;
- }
-
- /* Restore the tmp node to appropriate place. */
- queue->array[index] = tmp;
- if (queue->update != NULL)
- (*queue->update)(tmp, index);
-}
-
-struct pqueue *pqueue_create(void)
-{
- struct pqueue *queue;
-
- queue = XCALLOC(MTYPE_PQUEUE, sizeof(struct pqueue));
-
- queue->array =
- XCALLOC(MTYPE_PQUEUE_DATA, DATA_SIZE * PQUEUE_INIT_ARRAYSIZE);
- queue->array_size = PQUEUE_INIT_ARRAYSIZE;
-
- /* By default we want nothing to happen when a node changes. */
- queue->update = NULL;
- return queue;
-}
-
-void pqueue_delete(struct pqueue *queue)
-{
- XFREE(MTYPE_PQUEUE_DATA, queue->array);
- XFREE(MTYPE_PQUEUE, queue);
-}
-
-static int pqueue_expand(struct pqueue *queue)
-{
- void **newarray;
-
- newarray =
- XCALLOC(MTYPE_PQUEUE_DATA, queue->array_size * DATA_SIZE * 2);
-
- memcpy(newarray, queue->array, queue->array_size * DATA_SIZE);
-
- XFREE(MTYPE_PQUEUE_DATA, queue->array);
- queue->array = newarray;
- queue->array_size *= 2;
-
- return 1;
-}
-
-void pqueue_enqueue(void *data, struct pqueue *queue)
-{
- if (queue->size + 2 >= queue->array_size && !pqueue_expand(queue))
- return;
-
- queue->array[queue->size] = data;
- if (queue->update != NULL)
- (*queue->update)(data, queue->size);
- trickle_up(queue->size, queue);
- queue->size++;
-}
-
-void *pqueue_dequeue(struct pqueue *queue)
-{
- void *data = queue->array[0];
- queue->array[0] = queue->array[--queue->size];
- trickle_down(0, queue);
- return data;
-}
-
-void pqueue_remove_at(int index, struct pqueue *queue)
-{
- queue->array[index] = queue->array[--queue->size];
-
- if (index > 0
- && (*queue->cmp)(queue->array[index],
- queue->array[PARENT_OF(index)])
- < 0) {
- trickle_up(index, queue);
- } else {
- trickle_down(index, queue);
- }
-}
-
-void pqueue_remove(void *data, struct pqueue *queue)
-{
- for (int i = 0; i < queue->size; i++)
- if (queue->array[i] == data)
- pqueue_remove_at(i, queue);
-}
+++ /dev/null
-/* Priority queue functions.
- * Copyright (C) 2003 Yasuhiro Ohara
- *
- * This file is part of GNU Zebra.
- *
- * GNU Zebra 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 2, or (at your
- * option) any later version.
- *
- * GNU Zebra 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; see the file COPYING; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#ifndef _ZEBRA_PQUEUE_H
-#define _ZEBRA_PQUEUE_H
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-struct pqueue {
- void **array;
- int array_size;
- int size;
-
- int (*cmp)(void *, void *);
- void (*update)(void *node, int actual_position);
-};
-
-#define PQUEUE_INIT_ARRAYSIZE 32
-
-extern struct pqueue *pqueue_create(void);
-extern void pqueue_delete(struct pqueue *queue);
-
-extern void pqueue_enqueue(void *data, struct pqueue *queue);
-extern void *pqueue_dequeue(struct pqueue *queue);
-extern void pqueue_remove_at(int index, struct pqueue *queue);
-extern void pqueue_remove(void *data, struct pqueue *queue);
-
-extern void trickle_down(int index, struct pqueue *queue);
-extern void trickle_up(int index, struct pqueue *queue);
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif /* _ZEBRA_PQUEUE_H */
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