/*
- * Copyright (C) 2009-2011 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
*
* This file is part of libgit2, distributed under the GNU GPL v2 with
* a Linking Exception. For full terms see the included COPYING file.
*/
-
#ifndef INCLUDE_pqueue_h__
#define INCLUDE_pqueue_h__
-/** callback functions to get/set/compare the priority of an element */
-typedef int (*git_pqueue_cmp)(void *a, void *b);
+#include "vector.h"
-/** the priority queue handle */
-typedef struct {
- size_t size, avail, step;
- git_pqueue_cmp cmppri;
- void **d;
-} git_pqueue;
+typedef git_vector git_pqueue;
+enum {
+ /* flag meaning: don't grow heap, keep highest values only */
+ GIT_PQUEUE_FIXED_SIZE = (GIT_VECTOR_FLAG_MAX << 1),
+};
/**
- * initialize the queue
- *
- * @param n the initial estimate of the number of queue items for which memory
- * should be preallocated
- * @param cmppri the callback function to compare two nodes of the queue
+ * Initialize priority queue
*
- * @Return the handle or NULL for insufficent memory
- */
-int git_pqueue_init(git_pqueue *q, size_t n, git_pqueue_cmp cmppri);
-
-
-/**
- * free all memory used by the queue
- * @param q the queue
- */
-void git_pqueue_free(git_pqueue *q);
-
-/**
- * clear all the elements in the queue
- * @param q the queue
- */
-void git_pqueue_clear(git_pqueue *q);
-
-/**
- * return the size of the queue.
- * @param q the queue
- */
-size_t git_pqueue_size(git_pqueue *q);
-
+ * @param pq The priority queue struct to initialize
+ * @param flags Flags (see above) to control queue behavior
+ * @param init_size The initial queue size
+ * @param cmp The entry priority comparison function
+ * @return 0 on success, <0 on error
+ */
+extern int git_pqueue_init(
+ git_pqueue *pq,
+ uint32_t flags,
+ size_t init_size,
+ git_vector_cmp cmp);
+
+#define git_pqueue_free git_vector_free
+#define git_pqueue_clear git_vector_clear
+#define git_pqueue_size git_vector_length
+#define git_pqueue_get git_vector_get
/**
- * insert an item into the queue.
- * @param q the queue
- * @param d the item
- * @return 0 on success
- */
-int git_pqueue_insert(git_pqueue *q, void *d);
-
-
-/**
- * pop the highest-ranking item from the queue.
- * @param p the queue
- * @param d where to copy the entry to
- * @return NULL on error, otherwise the entry
+ * Insert a new item into the queue
+ *
+ * @param pq The priority queue
+ * @param item Pointer to the item data
+ * @return 0 on success, <0 on failure
*/
-void *git_pqueue_pop(git_pqueue *q);
-
+extern int git_pqueue_insert(git_pqueue *pq, void *item);
/**
- * access highest-ranking item without removing it.
- * @param q the queue
- * @param d the entry
- * @return NULL on error, otherwise the entry
+ * Remove the top item in the priority queue
+ *
+ * @param pq The priority queue
+ * @return item from heap on success, NULL if queue is empty
*/
-void *git_pqueue_peek(git_pqueue *q);
-
-#endif /* PQUEUE_H */
-/** @} */
+extern void *git_pqueue_pop(git_pqueue *pq);
+#endif