mirror of
https://github.com/brl/mutter.git
synced 2024-12-26 21:02:14 +00:00
108 lines
4.0 KiB
C
108 lines
4.0 KiB
C
/*
|
|
* SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008)
|
|
* Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved.
|
|
*
|
|
* Permission is hereby granted, free of charge, to any person obtaining a
|
|
* copy of this software and associated documentation files (the "Software"),
|
|
* to deal in the Software without restriction, including without limitation
|
|
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
|
|
* and/or sell copies of the Software, and to permit persons to whom the
|
|
* Software is furnished to do so, subject to the following conditions:
|
|
*
|
|
* The above copyright notice including the dates of first publication and
|
|
* either this permission notice or a reference to
|
|
* http://oss.sgi.com/projects/FreeB/
|
|
* shall be included in all copies or substantial portions of the Software.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
|
|
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
|
|
* SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
|
|
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF
|
|
* OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
|
|
* SOFTWARE.
|
|
*
|
|
* Except as contained in this notice, the name of Silicon Graphics, Inc.
|
|
* shall not be used in advertising or otherwise to promote the sale, use or
|
|
* other dealings in this Software without prior written authorization from
|
|
* Silicon Graphics, Inc.
|
|
*/
|
|
/*
|
|
** Author: Eric Veach, July 1994.
|
|
**
|
|
*/
|
|
|
|
#ifndef __priorityq_heap_h_
|
|
#define __priorityq_heap_h_
|
|
|
|
/* Use #define's so that another heap implementation can use this one */
|
|
|
|
#define PQkey PQHeapKey
|
|
#define PQhandle PQHeapHandle
|
|
#define PriorityQ PriorityQHeap
|
|
|
|
#define pqNewPriorityQ(leq) __gl_pqHeapNewPriorityQ(leq)
|
|
#define pqDeletePriorityQ(pq) __gl_pqHeapDeletePriorityQ(pq)
|
|
|
|
/* The basic operations are insertion of a new key (pqInsert),
|
|
* and examination/extraction of a key whose value is minimum
|
|
* (pqMinimum/pqExtractMin). Deletion is also allowed (pqDelete);
|
|
* for this purpose pqInsert returns a "handle" which is supplied
|
|
* as the argument.
|
|
*
|
|
* An initial heap may be created efficiently by calling pqInsert
|
|
* repeatedly, then calling pqInit. In any case pqInit must be called
|
|
* before any operations other than pqInsert are used.
|
|
*
|
|
* If the heap is empty, pqMinimum/pqExtractMin will return a NULL key.
|
|
* This may also be tested with pqIsEmpty.
|
|
*/
|
|
#define pqInit(pq) __gl_pqHeapInit(pq)
|
|
#define pqInsert(pq,key) __gl_pqHeapInsert(pq,key)
|
|
#define pqMinimum(pq) __gl_pqHeapMinimum(pq)
|
|
#define pqExtractMin(pq) __gl_pqHeapExtractMin(pq)
|
|
#define pqDelete(pq,handle) __gl_pqHeapDelete(pq,handle)
|
|
#define pqIsEmpty(pq) __gl_pqHeapIsEmpty(pq)
|
|
|
|
|
|
/* Since we support deletion the data structure is a little more
|
|
* complicated than an ordinary heap. "nodes" is the heap itself;
|
|
* active nodes are stored in the range 1..pq->size. When the
|
|
* heap exceeds its allocated size (pq->max), its size doubles.
|
|
* The children of node i are nodes 2i and 2i+1.
|
|
*
|
|
* Each node stores an index into an array "handles". Each handle
|
|
* stores a key, plus a pointer back to the node which currently
|
|
* represents that key (ie. nodes[handles[i].node].handle == i).
|
|
*/
|
|
|
|
typedef void *PQkey;
|
|
typedef long PQhandle;
|
|
typedef struct PriorityQ PriorityQ;
|
|
|
|
typedef struct { PQhandle handle; } PQnode;
|
|
typedef struct { PQkey key; PQhandle node; } PQhandleElem;
|
|
|
|
struct PriorityQ {
|
|
PQnode *nodes;
|
|
PQhandleElem *handles;
|
|
long size, max;
|
|
PQhandle freeList;
|
|
int initialized;
|
|
int (*leq)(PQkey key1, PQkey key2);
|
|
};
|
|
|
|
PriorityQ *pqNewPriorityQ( int (*leq)(PQkey key1, PQkey key2) );
|
|
void pqDeletePriorityQ( PriorityQ *pq );
|
|
|
|
void pqInit( PriorityQ *pq );
|
|
PQhandle pqInsert( PriorityQ *pq, PQkey key );
|
|
PQkey pqExtractMin( PriorityQ *pq );
|
|
void pqDelete( PriorityQ *pq, PQhandle handle );
|
|
|
|
|
|
#define __gl_pqHeapMinimum(pq) ((pq)->handles[(pq)->nodes[1].handle].key)
|
|
#define __gl_pqHeapIsEmpty(pq) ((pq)->size == 0)
|
|
|
|
#endif
|