-/* $Id$ */
-
/* a generic and efficient heap */
-/* Copyright (c) 2004 Arnaud Legrand. All rights reserved. */
+/* Copyright (c) 2004, 2005, 2007, 2008, 2009, 2010. The SimGrid Team.
+ * All rights reserved. */
/* This program is free software; you can redistribute it and/or modify it
* under the terms of the license (GNU LGPL) which comes with this package. */
#include "xbt/sysdep.h"
-#include "xbt/error.h"
+#include "xbt/log.h"
#include "heap_private.h"
+#include <stdio.h>
+
+static void xbt_heap_max_heapify(xbt_heap_t H);
+static void xbt_heap_increase_key(xbt_heap_t H, int i);
-/** \defgroup XBT_heap A generic heap data structure
+/** @addtogroup XBT_heap
* \brief This section describes the API to generic heap with O(log(n)) access.
*/
-XBT_LOG_NEW_DEFAULT_SUBCATEGORY(heap, xbt, "Heap");
-
-/** \name Functions
- * \ingroup XBT_heap
- */
-/*@{*/
/**
+ * @brief Creates a new heap.
* \param init_size initial size of the heap
* \param free_func function to call on each element when you want to free
* the whole heap (or NULL if nothing to do).
*
* Creates a new heap.
*/
-xbt_heap_t xbt_heap_new(int init_size, void_f_pvoid_t * const free_func)
+XBT_INLINE xbt_heap_t xbt_heap_new(int init_size,
+ void_f_pvoid_t const free_func)
{
xbt_heap_t H = xbt_new0(struct xbt_heap, 1);
H->size = init_size;
H->count = 0;
- H->items = (xbt_heapItem_t) xbt_new0(struct xbt_heapItem, init_size);
+ H->items = (xbt_heap_item_t) xbt_new0(struct xbt_heap_item, init_size);
H->free = free_func;
return H;
}
/**
- * \param H poor victim
- *
- * kilkil a heap and its content
+ * @brief Set the update callback function.
+ * @param H the heap we're working on
+ * \param update_callback function to call on each element to update its index when needed.
+ */
+XBT_INLINE void xbt_heap_set_update_callback(xbt_heap_t H,
+ void (*update_callback) (void
+ *,
+ int))
+{
+ H->update_callback = update_callback;
+}
+
+
+/**
+ * @brief kilkil a heap and its content
+ * @param H poor victim
*/
void xbt_heap_free(xbt_heap_t H)
{
int i;
if (H->free)
for (i = 0; i < H->count; i++)
- H->free(H->items[i].content);
+ (*(H->free)) (H->items[i].content);
free(H->items);
free(H);
return;
}
/**
- * \param H the heap we're working on
- * \return the number of elements in the heap
+ * @brief returns the number of elements in the heap
+ * @param H the heap we're working on
+ * @return the number of elements in the heap
*/
-int xbt_heap_size(xbt_heap_t H)
+XBT_INLINE int xbt_heap_size(xbt_heap_t H)
{
return (H->count);
}
/**
+ * @brief Add an element into the heap.
* \param H the heap we're working on
* \param content the object you want to add to the heap
* \param key the key associated to this object
*
- * Add an element int the heap. The element with the smallest key is
- * automatically moved at the top of the heap.
+ * The element with the smallest key is automatically moved at the top of the heap.
*/
void xbt_heap_push(xbt_heap_t H, void *content, double key)
{
int count = ++(H->count);
+
int size = H->size;
- xbt_heapItem_t item;
+ xbt_heap_item_t item;
+
if (count > size) {
- H->size = 2 * size + 1;
+ H->size = (size << 1) + 1;
H->items =
- (void *) realloc(H->items,
- (H->size) * sizeof(struct xbt_heapItem));
+ (void *) realloc(H->items,
+ (H->size) * sizeof(struct xbt_heap_item));
}
+
item = &(H->items[count - 1]);
item->key = key;
item->content = content;
- xbt_heap_increaseKey(H, count - 1);
+ xbt_heap_increase_key(H, count - 1);
return;
}
/**
+ * @brief Extracts from the heap and returns the element with the smallest key.
* \param H the heap we're working on
* \return the element with the smallest key
*
*/
void *xbt_heap_pop(xbt_heap_t H)
{
+ xbt_heap_item_t items = H->items;
+ int size = H->size;
void *max;
if (H->count == 0)
max = CONTENT(H, 0);
- H->items[0] = H->items[(H->count) - 1];
+ items[0] = items[(H->count) - 1];
(H->count)--;
- xbt_heap_maxHeapify(H);
- if (H->count < H->size / 4 && H->size > 16) {
- H->size = H->size / 2 + 1;
+ xbt_heap_max_heapify(H);
+ if (H->count < size >> 2 && size > 16) {
+ size = (size >> 1) + 1;
H->items =
- (void *) realloc(H->items,
- (H->size) * sizeof(struct xbt_heapItem));
+ (void *) realloc(items,
+ size * sizeof(struct xbt_heap_item));
+ H->size = size;
}
+
+ if (H->update_callback)
+ H->update_callback(max, -1);
return max;
}
/**
+ * @brief Extracts from the heap and returns the element at position i.
+ * \param H the heap we're working on
+ * \param i element position
+ * \return the element at position i if ok, NULL otherwise
+ *
+ * Extracts from the heap and returns the element at position i. The head is automatically reorded.
+ */
+void *xbt_heap_remove(xbt_heap_t H, int i)
+{
+ if ((i < 0) || (i > H->count - 1))
+ return NULL;
+ /* put element i at head */
+ if (i > 0) {
+ KEY(H, i) = MIN_KEY_VALUE;
+ xbt_heap_increase_key(H, i);
+ }
+
+ return xbt_heap_pop(H);
+}
+
+/**
+ * @brief returns the smallest key in the heap (heap unchanged)
* \param H the heap we're working on
*
* \return the smallest key in the heap without modifying the heap.
*/
-double xbt_heap_maxkey(xbt_heap_t H)
+XBT_INLINE double xbt_heap_maxkey(xbt_heap_t H)
{
- xbt_assert0(H->count != 0,"Empty heap");
+ xbt_assert(H->count != 0, "Empty heap");
return KEY(H, 0);
}
/**
+ * @brief returns the value associated to the smallest key in the heap (heap unchanged)
* \param H the heap we're working on
*
* \return the value associated to the smallest key in the heap
*/
void *xbt_heap_maxcontent(xbt_heap_t H)
{
- xbt_assert0(H->count != 0,"Empty heap");
+ xbt_assert(H->count != 0, "Empty heap");
return CONTENT(H, 0);
}
/* <<<< private >>>>
* \param H the heap we're working on
- *
+ *
* Restores the heap property once an element has been deleted.
*/
-static void xbt_heap_maxHeapify(xbt_heap_t H)
+static void xbt_heap_max_heapify(xbt_heap_t H)
{
int i = 0;
+ int count = H->count;
+ xbt_heap_item_t items = H->items;
+
while (1) {
int greatest = i;
int l = LEFT(i);
- int r = RIGHT(i);
- int count = H->count;
- if (l < count && KEY(H, l) < KEY(H, i))
+ int r = l + 1;
+ if (l < count && items[l].key < items[i].key)
greatest = l;
- if (r < count && KEY(H, r) < KEY(H, greatest))
+ if (r < count && items[r].key < items[greatest].key)
greatest = r;
if (greatest != i) {
- struct xbt_heapItem tmp = H->items[i];
- H->items[i] = H->items[greatest];
- H->items[greatest] = tmp;
+ struct xbt_heap_item tmp = items[i];
+ items[i] = items[greatest];
+ items[greatest] = tmp;
+ if (H->update_callback)
+ H->update_callback(items[i].content, i);
i = greatest;
- } else
+ } else {
+ if (H->update_callback)
+ H->update_callback(items[i].content, i);
return;
+ }
}
}
/* <<<< private >>>>
* \param H the heap we're working on
* \param i an item position in the heap
- *
+ *
* Moves up an item at position i to its correct position. Works only
* when called from xbt_heap_push. Do not use otherwise.
*/
-static void xbt_heap_increaseKey(xbt_heap_t H, int i)
+static void xbt_heap_increase_key(xbt_heap_t H, int i)
{
- while (i > 0 && KEY(H, PARENT(i)) > KEY(H, i)) {
- struct xbt_heapItem tmp = H->items[i];
- H->items[i] = H->items[PARENT(i)];
- H->items[PARENT(i)] = tmp;
- i = PARENT(i);
+ xbt_heap_item_t items = H->items;
+ int p = PARENT(i);
+ while (i > 0 && items[p].key > items[i].key) {
+ struct xbt_heap_item tmp = items[i];
+ items[i] = items[p];
+ items[p] = tmp;
+ if (H->update_callback)
+ H->update_callback(items[i].content, i);
+ i = p;
+ p = PARENT(i);
}
+ if (H->update_callback)
+ H->update_callback(items[i].content, i);
return;
}
-/*@}*/
