xref: /lsquic/src/liblsquic/lsquic_min_heap.h

/* Copyright (c) 2017 - 2022 LiteSpeed Technologies Inc.  See LICENSE. */
/*
 * lsquic_min_heap.h -- Min-heap for pointers
 */

#ifndef LSQUIC_MIN_HEAP_H
#define LSQUIC_MIN_HEAP_H 1


struct min_heap_elem
{
    void                *mhe_item;
    uint64_t             mhe_val;
};


struct min_heap
{
    struct min_heap_elem    *mh_elems;
    unsigned                 mh_nalloc,
                             mh_nelem;
};


void
lsquic_mh_insert (struct min_heap *, void *item, uint64_t val);

void *
lsquic_mh_pop (struct min_heap *);

#define lsquic_mh_peek(heap) ((heap)->mh_elems[0].mhe_item)

#define lsquic_mh_count(heap) (+(heap)->mh_nelem)

#define lsquic_mh_nalloc(heap) (+(heap)->mh_nalloc)

#define MHE_PARENT(i) ((i - 1) / 2)
#define MHE_LCHILD(i) (2 * i + 1)
#define MHE_RCHILD(i) (2 * i + 2)

#endif