#ifndef _LINUX_PRIO_HEAP_H
#define _LINUX_PRIO_HEAP_H

/*
* Simple insertion-only static-sized priority heap containing
* pointers, based on CLR, chapter 7
*/

#include <linux/gfp.h>

/**
* struct ptr_heap - simple static-sized priority heap
* @ptrs - pointer to data area
* @max - max number of elements that can be stored in @ptrs
* @size - current number of valid elements in @ptrs (in the range 0..@size-1
* @gt: comparison operator, which should implement "greater than"
*/
struct ptr_heap {
void **ptrs;
int max;
int size;
int (*gt)(void *, void *);
};

/**
* heap_init - initialize an empty heap with a given memory size
* @heap: the heap structure to be initialized
* @size: amount of memory to use in bytes
* @gfp_mask: mask to pass to kmalloc()
* @gt: comparison operator, which should implement "greater than"
*/
extern int heap_init(struct ptr_heap *heap, size_t size, gfp_t gfp_mask,
int (*gt)(void *, void *));

/**
* heap_free - release a heap's storage
* @heap: the heap structure whose data should be released
*/
void heap_free(struct ptr_heap *heap);

/**
* heap_insert - insert a value into the heap and return any overflowed value
* @heap: the heap to be operated on
* @p: the pointer to be inserted
*
* Attempts to insert the given value into the priority heap. If the
* heap is full prior to the insertion, then the resulting heap will
* consist of the smallest @max elements of the original heap and the
* new element; the greatest element will be removed from the heap and
* returned. Note that the returned element will be the new element
* (i.e. no change to the heap) if the new element is greater than all
* elements currently in the heap.
*/
extern void *heap_insert(struct ptr_heap *heap, void *p);



#endif /* _LINUX_PRIO_HEAP_H */