lib/heap.c, lib/heap.h: New generic priority queue data structure

This commit is contained in:
tedbullock 2007-09-12 04:32:00 +00:00
parent 056cafdee1
commit 04caf4ff61
6 changed files with 233 additions and 17 deletions

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@ -1,3 +1,7 @@
2007-09-11 Ted Bullock <tbullock@canada.com>
* lib/heap.c, lib/heap.h: New generic priority queue data structure
2007-07-15 Ted Bullock <tbullock@canada.com>
* lib/queue.c, lib/queue.h: New generic queue data structure

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@ -4,4 +4,4 @@ AM_LDFLAGS =
noinst_LIBRARIES = libutil.a
libutil_a_SOURCES = getopt.c getopt.h getopt1.c ssl_writev.c generic_types.h \
queue.c queue.h
queue.c queue.h heap.c heap.h

167
httperf/src/lib/heap.c Normal file
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@ -0,0 +1,167 @@
/*
* Copyright (C) 2007 Ted Bullock <tbullock@canada.com>
*
* This file is part of httperf, a web server performance measurment tool.
*
* 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.
*
* In addition, as a special exception, the copyright holders give permission
* to link the code of this work with the OpenSSL project's "OpenSSL" library
* (or with modified versions of it that use the same license as the "OpenSSL"
* library), and distribute linked combinations including the two. You must
* obey the GNU General Public License in all respects for all of the code
* used other than "OpenSSL". If you modify this file, you may extend this
* exception to your version of the file, but you are not obligated to do so.
* If you do not wish to do so, delete this exception statement from your
* 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 the Free Software Foundation, Inc., 51
* Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
*/
#include "config.h"
#include <stdlib.h>
#include <stdbool.h>
#include <generic_types.h>
#include <heap.h>
#define Minimum_Heap_Size 10
struct Heap {
u_long array_size;
u_long num_elements;
heap_compare compare;
Any_Type storage[]; /* c99 Flexible Array Member */
};
struct Heap *
create_heap(u_long size, heap_compare compare_callback)
{
struct Heap *h;
if (size < Minimum_Heap_Size)
size = Minimum_Heap_Size;
/*
* We are using c99 Flexible Array Members so we can do this :)
*/
h = malloc(sizeof(struct Heap) + sizeof(Any_Type) * size);
if (!h)
return NULL;
h->array_size = size;
h->num_elements = 0;
h->compare = compare_callback;
return h;
}
_Bool
is_heap_empty(struct Heap * h)
{
return h->num_elements == 0;
}
_Bool
is_heap_full(struct Heap * h)
{
return h->array_size == h->num_elements;
}
u_long
num_heap_elements(struct Heap * h)
{
return h->num_elements;
}
void
free_heap(struct Heap *h)
{
if (h != NULL)
free(h);
}
#define PARENT(i) (i/2)
_Bool
insert(Any_Type a, struct Heap *h)
{
u_long i, parent;
if (is_heap_full(h))
return false;
i = ++h->num_elements;
/*
* find the correct place to insert
*/
while ((i > 1) && (*h->compare) (h->storage[PARENT(i)], a)) {
h->storage[i] = h->storage[PARENT(i)];
i = PARENT(i);
}
h->storage[i] = a;
return true;
}
static void
percolate(struct Heap *h, u_long hole)
{
int child;
Any_Type dest_val = h->storage[hole];
for (; hole * 2 <= h->num_elements; hole = child) {
child = hole * 2;
if (child != h->num_elements
&& (*h->compare) (h->storage[child + 1],
h->storage[child + 1]))
child++;
if ((*h->compare) (h->storage[child + 1], dest_val))
h->storage[hole] = h->storage[child];
else
break;
}
h->storage[hole] = dest_val;
}
Any_Type
remove_min(struct Heap * h)
{
if(is_heap_empty(h))
return (Any_Type) 0;
else {
Any_Type min = h->storage[1];
h->storage[1] = h->storage[h->num_elements--];
percolate(h, 1);
return min;
}
}
Any_Type
poll_min(struct Heap * h)
{
if(is_heap_empty(h))
return (Any_Type) 0;
else
return h->storage[1];
}
void
heap_for_each(struct Heap *h, heap_for_each_action action)
{
for(u_long i = 1; i <= h->num_elements; i++)
{
(*action)(h->storage[i]);
}
}

51
httperf/src/lib/heap.h Normal file
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@ -0,0 +1,51 @@
/*
* Copyright (C) 2007 Ted Bullock <tbullock@canada.com>
*
* This file is part of httperf, a web server performance measurment tool.
*
* 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.
*
* In addition, as a special exception, the copyright holders give permission
* to link the code of this work with the OpenSSL project's "OpenSSL" library
* (or with modified versions of it that use the same license as the "OpenSSL"
* library), and distribute linked combinations including the two. You must
* obey the GNU General Public License in all respects for all of the code
* used other than "OpenSSL". If you modify this file, you may extend this
* exception to your version of the file, but you are not obligated to do so.
* If you do not wish to do so, delete this exception statement from your
* 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 the Free Software Foundation, Inc., 51
* Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
*/
#ifndef heap_h
#define heap_h
struct Heap;
typedef _Bool (*heap_compare) (Any_Type, Any_Type);
typedef void (*heap_for_each_action) (Any_Type);
struct Heap *create_heap(u_long, heap_compare);
_Bool is_heap_empty(struct Heap *);
_Bool is_heap_full(struct Heap *);
u_long num_heap_elements(struct Heap *);
void free_heap(struct Heap *);
_Bool insert(Any_Type, struct Heap *);
Any_Type remove_min(struct Heap *);
Any_Type poll_min(struct Heap *);
void heap_for_each(struct Heap *, heap_for_each_action);
#endif /* Heap_h */

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@ -31,12 +31,9 @@
#include "config.h"
#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <generic_types.h>
#include <queue.h>
#include <httperf.h>
#define Minimum_Wheel_Size 10
@ -71,11 +68,8 @@ create_queue(u_long size)
* Again, we are using c99 Flexible Array Members so we can do this :)
*/
q = malloc(sizeof(struct Queue) + sizeof(Any_Type) * size);
if (!q) {
fprintf(stderr, "%s.create_queue: %s\n", prog_name,
strerror(errno));
return 0;
}
if (q == NULL)
return NULL;
q->wheel_size = size;
empty_queue(q);
@ -109,16 +103,15 @@ enqueue(Any_Type a, struct Queue *q)
{
if (is_queue_full(q))
return 0;
else {
q->num_elements++;
if (++q->last_element == q->wheel_size) {
q->last_element = 0;
}
q->num_elements++;
q->wheel[q->last_element] = a;
}
if (++q->last_element == q->wheel_size)
q->last_element = 0;
q->wheel[q->last_element] = a;
return 1;
}
void

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@ -41,5 +41,6 @@ int enqueue(Any_Type, struct Queue *);
Any_Type get_front(struct Queue *);
void dequeue(struct Queue *);
Any_Type get_front_and_dequeue(struct Queue *);
void print_vp(struct Queue *);
#endif /* queue_h */