mirror of
https://git.code.sf.net/p/quake/quakeforge
synced 2024-11-30 08:00:51 +00:00
020ada9fb1
clang doesn't like the same variable name being used in nested expression statements, so give the "safety" variables in reused macros semi-meaningful (based on macro name) tails to keep them separate.
124 lines
3.5 KiB
C
124 lines
3.5 KiB
C
/*
|
|
pqueue.h
|
|
|
|
Priority Queues
|
|
|
|
Copyright (C) 2021 Bill Currie <bill@taniwha.org>
|
|
|
|
Author: Bill Currie <bill@taniwha.org>
|
|
Date: 2021/08/02
|
|
|
|
This program 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
|
|
of the License, or (at your option) any later version.
|
|
|
|
This program 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; if not, write to:
|
|
|
|
Free Software Foundation, Inc.
|
|
59 Temple Place - Suite 330
|
|
Boston, MA 02111-1307, USA
|
|
|
|
*/
|
|
|
|
#ifndef __QF_pqueue_h
|
|
#define __QF_pqueue_h
|
|
|
|
#include <stdlib.h>
|
|
|
|
#include "QF/heapsort.h"
|
|
#include "QF/sys.h"
|
|
|
|
/** \defgroup pqueue Priority Queues
|
|
\ingroup utils
|
|
|
|
Priority queue management
|
|
*/
|
|
///@{
|
|
|
|
/** The structure def for a priority queue with elements of the given type.
|
|
|
|
This is just the def of a struct delcaration: it is useless on its own.
|
|
The intended usage is something like:
|
|
|
|
typedef struct priority_queue_s PQUEUE_TYPE (int) priority_queue_t;
|
|
|
|
This allows full flexibility in just how the actual type is used.
|
|
|
|
The \a size field is the number of elements currently in the queue, and
|
|
the \a maxSize field is the number of elements the queue can hold. The
|
|
priority queue functions will never resize the array. However, with a
|
|
little glue logic, priority queues can be used with dynamic arrays.
|
|
|
|
\param T The type to use for the element array, which is accessed
|
|
by the \a a field.
|
|
*/
|
|
#define PQUEUE_TYPE(T) \
|
|
{ \
|
|
size_t size; \
|
|
size_t maxSize; \
|
|
T *a; \
|
|
int (*compare) (const T *a, const T *b, void *data); \
|
|
void *data; \
|
|
}
|
|
|
|
#define PQUEUE_IS_EMPTY(queue) ((queue)->size == 0)
|
|
|
|
#define PQUEUE_IS_FULL(queue) \
|
|
({ \
|
|
__auto_type q_f = (queue); \
|
|
q_f->size == q_f->maxSize; \
|
|
})
|
|
|
|
#define PQUEUE_PEEK(queue) ((queue)->a[0])
|
|
|
|
#define PQUEUE_INSERT(queue, value) \
|
|
do { \
|
|
__auto_type q = (queue); \
|
|
if (PQUEUE_IS_FULL (q)) { \
|
|
Sys_Error ("Priority queue full"); \
|
|
} \
|
|
q->a[q->size++] = (value); \
|
|
heap_swim_r (q->a, q->size - 1, q->size, sizeof (q->a[0]), \
|
|
(__compar_d_fn_t) q->compare, q->data); \
|
|
} while (0)
|
|
|
|
#define PQUEUE_REMOVE(queue) \
|
|
({ \
|
|
__auto_type q = (queue); \
|
|
if (PQUEUE_IS_EMPTY (q)) { \
|
|
Sys_Error ("Priority queue empty"); \
|
|
} \
|
|
__auto_type value = q->a[0]; \
|
|
q->a[0] = q->a[--q->size]; \
|
|
heap_sink_r (q->a, 0, q->size, sizeof (q->a[0]), \
|
|
(__compar_d_fn_t) q->compare, q->data); \
|
|
value; \
|
|
})
|
|
|
|
#define PQUEUE_ADJUST(queue, index) \
|
|
do { \
|
|
__auto_type q = (queue); \
|
|
size_t ind = (index); \
|
|
if (ind >= q->size) { \
|
|
Sys_Error ("Priority queue index error"); \
|
|
} \
|
|
if (ind>0 && q->compare(q->a + ind, q->a + (ind-1)/2, q->data)>0) { \
|
|
heap_swim_r (q->a, ind, q->size, sizeof (q->a[0]), \
|
|
(__compar_d_fn_t) q->compare, q->data); \
|
|
} else { \
|
|
heap_sink_r (q->a, ind, q->size, sizeof (q->a[0]), \
|
|
(__compar_d_fn_t) q->compare, q->data); \
|
|
} \
|
|
} while (0)
|
|
|
|
///@}
|
|
|
|
#endif//__QF_pqueue_h
|