+/**
+ * collectd - src/utils_heap.h
+ * Copyright (C) 2009 Florian octo Forster
+ *
+ * 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 and this permission notice 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 THE
+ * AUTHORS OR COPYRIGHT HOLDERS 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.
+ *
+ * Authors:
+ * Florian octo Forster <octo at collectd.org>
+ **/
+
+#ifndef UTILS_HEAP_H
+#define UTILS_HEAP_H 1
+
+struct c_heap_s;
+typedef struct c_heap_s c_heap_t;
+
+/*
+ * NAME
+ * c_heap_create
+ *
+ * DESCRIPTION
+ * Allocates a new heap.
+ *
+ * PARAMETERS
+ * `compare' The function-pointer `compare' is used to compare two keys. It
+ * has to return less than zero if it's first argument is smaller
+ * then the second argument, more than zero if the first argument
+ * is bigger than the second argument and zero if they are equal.
+ * If your keys are char-pointers, you can use the `strcmp'
+ * function from the libc here.
+ *
+ * RETURN VALUE
+ * A c_heap_t-pointer upon success or NULL upon failure.
+ */
+c_heap_t *c_heap_create (int (*compare) (const void *, const void *));
+
+/*
+ * NAME
+ * c_heap_destroy
+ *
+ * DESCRIPTION
+ * Deallocates a heap. Stored value- and key-pointer are lost, but of course
+ * not freed.
+ */
+void c_heap_destroy (c_heap_t *h);
+
+/*
+ * NAME
+ * c_heap_insert
+ *
+ * DESCRIPTION
+ * Stores the key-value-pair in the heap pointed to by `h'.
+ *
+ * PARAMETERS
+ * `h' Heap to store the data in.
+ * `ptr' Value to be stored. This is typically a pointer to a data
+ * structure. The data structure is of course *not* copied and may
+ * not be free'd before the pointer has been removed from the heap
+ * again.
+ *
+ * RETURN VALUE
+ * Zero upon success, non-zero otherwise. It's less than zero if an error
+ * occurred or greater than zero if the key is already stored in the tree.
+ */
+int c_heap_insert (c_heap_t *h, void *ptr);
+
+/*
+ * NAME
+ * c_heap_get_root
+ *
+ * DESCRIPTION
+ * Removes the value at the root of the heap and returns both, key and value.
+ *
+ * PARAMETERS
+ * `h' Heap to remove key-value-pair from.
+ *
+ * RETURN VALUE
+ * The pointer passed to `c_heap_insert' or NULL if there are no more
+ * elements in the heap (or an error occurred).
+ */
+void *c_heap_get_root (c_heap_t *h);
+
+#endif /* UTILS_HEAP_H */
+/* vim: set sw=2 sts=2 et : */