mirror of
https://github.com/brl/mutter.git
synced 2024-12-18 00:52:05 +00:00
262 lines
7.0 KiB
C
262 lines
7.0 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.
|
|
**
|
|
*/
|
|
|
|
#include "gluos.h"
|
|
#include <stddef.h>
|
|
#include <assert.h>
|
|
#include <limits.h> /* LONG_MAX */
|
|
#include "memalloc.h"
|
|
|
|
/* Include all the code for the regular heap-based queue here. */
|
|
|
|
#include "priorityq-heap.c"
|
|
|
|
/* Now redefine all the function names to map to their "Sort" versions. */
|
|
|
|
#include "priorityq-sort.h"
|
|
|
|
/* really __gl_pqSortNewPriorityQ */
|
|
PriorityQ *pqNewPriorityQ( int (*leq)(PQkey key1, PQkey key2) )
|
|
{
|
|
PriorityQ *pq = (PriorityQ *)memAlloc( sizeof( PriorityQ ));
|
|
if (pq == NULL) return NULL;
|
|
|
|
pq->heap = __gl_pqHeapNewPriorityQ( leq );
|
|
if (pq->heap == NULL) {
|
|
memFree(pq);
|
|
return NULL;
|
|
}
|
|
|
|
pq->keys = (PQHeapKey *)memAlloc( INIT_SIZE * sizeof(pq->keys[0]) );
|
|
if (pq->keys == NULL) {
|
|
__gl_pqHeapDeletePriorityQ(pq->heap);
|
|
memFree(pq);
|
|
return NULL;
|
|
}
|
|
|
|
pq->order = NULL;
|
|
pq->size = 0;
|
|
pq->max = INIT_SIZE;
|
|
pq->initialized = FALSE;
|
|
pq->leq = leq;
|
|
return pq;
|
|
}
|
|
|
|
/* really __gl_pqSortDeletePriorityQ */
|
|
void pqDeletePriorityQ( PriorityQ *pq )
|
|
{
|
|
assert(pq != NULL);
|
|
if (pq->heap != NULL) __gl_pqHeapDeletePriorityQ( pq->heap );
|
|
if (pq->order != NULL) memFree( pq->order );
|
|
if (pq->keys != NULL) memFree( pq->keys );
|
|
memFree( pq );
|
|
}
|
|
|
|
|
|
#define LT(x,y) (! LEQ(y,x))
|
|
#define GT(x,y) (! LEQ(x,y))
|
|
#define Swap(a,b) do{PQkey *tmp = *a; *a = *b; *b = tmp;}while(0)
|
|
|
|
/* really __gl_pqSortInit */
|
|
int pqInit( PriorityQ *pq )
|
|
{
|
|
PQkey **p, **r, **i, **j, *piv;
|
|
struct { PQkey **p, **r; } Stack[50], *top = Stack;
|
|
unsigned long seed = 2016473283;
|
|
|
|
/* Create an array of indirect pointers to the keys, so that we
|
|
* the handles we have returned are still valid.
|
|
*/
|
|
/*
|
|
pq->order = (PQHeapKey **)memAlloc( (size_t)
|
|
(pq->size * sizeof(pq->order[0])) );
|
|
*/
|
|
pq->order = (PQHeapKey **)memAlloc( (size_t)
|
|
((pq->size+1) * sizeof(pq->order[0])) );
|
|
/* the previous line is a patch to compensate for the fact that IBM */
|
|
/* machines return a null on a malloc of zero bytes (unlike SGI), */
|
|
/* so we have to put in this defense to guard against a memory */
|
|
/* fault four lines down. from fossum@austin.ibm.com. */
|
|
if (pq->order == NULL) return 0;
|
|
|
|
p = pq->order;
|
|
r = p + pq->size - 1;
|
|
for( piv = pq->keys, i = p; i <= r; ++piv, ++i ) {
|
|
*i = piv;
|
|
}
|
|
|
|
/* Sort the indirect pointers in descending order,
|
|
* using randomized Quicksort
|
|
*/
|
|
top->p = p; top->r = r; ++top;
|
|
while( --top >= Stack ) {
|
|
p = top->p;
|
|
r = top->r;
|
|
while( r > p + 10 ) {
|
|
seed = seed * 1539415821 + 1;
|
|
i = p + seed % (r - p + 1);
|
|
piv = *i;
|
|
*i = *p;
|
|
*p = piv;
|
|
i = p - 1;
|
|
j = r + 1;
|
|
do {
|
|
do { ++i; } while( GT( **i, *piv ));
|
|
do { --j; } while( LT( **j, *piv ));
|
|
Swap( i, j );
|
|
} while( i < j );
|
|
Swap( i, j ); /* Undo last swap */
|
|
if( i - p < r - j ) {
|
|
top->p = j+1; top->r = r; ++top;
|
|
r = i-1;
|
|
} else {
|
|
top->p = p; top->r = i-1; ++top;
|
|
p = j+1;
|
|
}
|
|
}
|
|
/* Insertion sort small lists */
|
|
for( i = p+1; i <= r; ++i ) {
|
|
piv = *i;
|
|
for( j = i; j > p && LT( **(j-1), *piv ); --j ) {
|
|
*j = *(j-1);
|
|
}
|
|
*j = piv;
|
|
}
|
|
}
|
|
pq->max = pq->size;
|
|
pq->initialized = TRUE;
|
|
__gl_pqHeapInit( pq->heap ); /* always succeeds */
|
|
|
|
#ifndef NDEBUG
|
|
p = pq->order;
|
|
r = p + pq->size - 1;
|
|
for( i = p; i < r; ++i ) {
|
|
assert( LEQ( **(i+1), **i ));
|
|
}
|
|
#endif
|
|
|
|
return 1;
|
|
}
|
|
|
|
/* really __gl_pqSortInsert */
|
|
/* returns LONG_MAX iff out of memory */
|
|
PQhandle pqInsert( PriorityQ *pq, PQkey keyNew )
|
|
{
|
|
long curr;
|
|
|
|
if( pq->initialized ) {
|
|
return __gl_pqHeapInsert( pq->heap, keyNew );
|
|
}
|
|
curr = pq->size;
|
|
if( ++ pq->size >= pq->max ) {
|
|
PQkey *saveKey= pq->keys;
|
|
|
|
/* If the heap overflows, double its size. */
|
|
pq->max <<= 1;
|
|
pq->keys = (PQHeapKey *)memRealloc( pq->keys,
|
|
(size_t)
|
|
(pq->max * sizeof( pq->keys[0] )));
|
|
if (pq->keys == NULL) {
|
|
pq->keys = saveKey; /* restore ptr to free upon return */
|
|
return LONG_MAX;
|
|
}
|
|
}
|
|
assert(curr != LONG_MAX);
|
|
pq->keys[curr] = keyNew;
|
|
|
|
/* Negative handles index the sorted array. */
|
|
return -(curr+1);
|
|
}
|
|
|
|
/* really __gl_pqSortExtractMin */
|
|
PQkey pqExtractMin( PriorityQ *pq )
|
|
{
|
|
PQkey sortMin, heapMin;
|
|
|
|
if( pq->size == 0 ) {
|
|
return __gl_pqHeapExtractMin( pq->heap );
|
|
}
|
|
sortMin = *(pq->order[pq->size-1]);
|
|
if( ! __gl_pqHeapIsEmpty( pq->heap )) {
|
|
heapMin = __gl_pqHeapMinimum( pq->heap );
|
|
if( LEQ( heapMin, sortMin )) {
|
|
return __gl_pqHeapExtractMin( pq->heap );
|
|
}
|
|
}
|
|
do {
|
|
-- pq->size;
|
|
} while( pq->size > 0 && *(pq->order[pq->size-1]) == NULL );
|
|
return sortMin;
|
|
}
|
|
|
|
/* really __gl_pqSortMinimum */
|
|
PQkey pqMinimum( PriorityQ *pq )
|
|
{
|
|
PQkey sortMin, heapMin;
|
|
|
|
if( pq->size == 0 ) {
|
|
return __gl_pqHeapMinimum( pq->heap );
|
|
}
|
|
sortMin = *(pq->order[pq->size-1]);
|
|
if( ! __gl_pqHeapIsEmpty( pq->heap )) {
|
|
heapMin = __gl_pqHeapMinimum( pq->heap );
|
|
if( LEQ( heapMin, sortMin )) {
|
|
return heapMin;
|
|
}
|
|
}
|
|
return sortMin;
|
|
}
|
|
|
|
/* really __gl_pqSortIsEmpty */
|
|
int pqIsEmpty( PriorityQ *pq )
|
|
{
|
|
return (pq->size == 0) && __gl_pqHeapIsEmpty( pq->heap );
|
|
}
|
|
|
|
/* really __gl_pqSortDelete */
|
|
void pqDelete( PriorityQ *pq, PQhandle curr )
|
|
{
|
|
if( curr >= 0 ) {
|
|
__gl_pqHeapDelete( pq->heap, curr );
|
|
return;
|
|
}
|
|
curr = -(curr+1);
|
|
assert( curr < pq->max && pq->keys[curr] != NULL );
|
|
|
|
pq->keys[curr] = NULL;
|
|
while( pq->size > 0 && *(pq->order[pq->size-1]) == NULL ) {
|
|
-- pq->size;
|
|
}
|
|
}
|