minheap-internal.h [plain text]
#ifndef MINHEAP_INTERNAL_H_INCLUDED_
#define MINHEAP_INTERNAL_H_INCLUDED_
#include "event2/event-config.h"
#include "evconfig-private.h"
#include "event2/event.h"
#include "event2/event_struct.h"
#include "event2/util.h"
#include "util-internal.h"
#include "mm-internal.h"
typedef struct min_heap
{
struct event** p;
unsigned n, a;
} min_heap_t;
static inline void min_heap_ctor_(min_heap_t* s);
static inline void min_heap_dtor_(min_heap_t* s);
static inline void min_heap_elem_init_(struct event* e);
static inline int min_heap_elt_is_top_(const struct event *e);
static inline int min_heap_empty_(min_heap_t* s);
static inline unsigned min_heap_size_(min_heap_t* s);
static inline struct event* min_heap_top_(min_heap_t* s);
static inline int min_heap_reserve_(min_heap_t* s, unsigned n);
static inline int min_heap_push_(min_heap_t* s, struct event* e);
static inline struct event* min_heap_pop_(min_heap_t* s);
static inline int min_heap_adjust_(min_heap_t *s, struct event* e);
static inline int min_heap_erase_(min_heap_t* s, struct event* e);
static inline void min_heap_shift_up_(min_heap_t* s, unsigned hole_index, struct event* e);
static inline void min_heap_shift_up_unconditional_(min_heap_t* s, unsigned hole_index, struct event* e);
static inline void min_heap_shift_down_(min_heap_t* s, unsigned hole_index, struct event* e);
#define min_heap_elem_greater(a, b) \
(evutil_timercmp(&(a)->ev_timeout, &(b)->ev_timeout, >))
void min_heap_ctor_(min_heap_t* s) { s->p = 0; s->n = 0; s->a = 0; }
void min_heap_dtor_(min_heap_t* s) { if (s->p) mm_free(s->p); }
void min_heap_elem_init_(struct event* e) { e->ev_timeout_pos.min_heap_idx = -1; }
int min_heap_empty_(min_heap_t* s) { return 0u == s->n; }
unsigned min_heap_size_(min_heap_t* s) { return s->n; }
struct event* min_heap_top_(min_heap_t* s) { return s->n ? *s->p : 0; }
int min_heap_push_(min_heap_t* s, struct event* e)
{
if (min_heap_reserve_(s, s->n + 1))
return -1;
min_heap_shift_up_(s, s->n++, e);
return 0;
}
struct event* min_heap_pop_(min_heap_t* s)
{
if (s->n)
{
struct event* e = *s->p;
min_heap_shift_down_(s, 0u, s->p[--s->n]);
e->ev_timeout_pos.min_heap_idx = -1;
return e;
}
return 0;
}
int min_heap_elt_is_top_(const struct event *e)
{
return e->ev_timeout_pos.min_heap_idx == 0;
}
int min_heap_erase_(min_heap_t* s, struct event* e)
{
if (-1 != e->ev_timeout_pos.min_heap_idx)
{
struct event *last = s->p[--s->n];
unsigned parent = (e->ev_timeout_pos.min_heap_idx - 1) / 2;
if (e->ev_timeout_pos.min_heap_idx > 0 && min_heap_elem_greater(s->p[parent], last))
min_heap_shift_up_unconditional_(s, e->ev_timeout_pos.min_heap_idx, last);
else
min_heap_shift_down_(s, e->ev_timeout_pos.min_heap_idx, last);
e->ev_timeout_pos.min_heap_idx = -1;
return 0;
}
return -1;
}
int min_heap_adjust_(min_heap_t *s, struct event *e)
{
if (-1 == e->ev_timeout_pos.min_heap_idx) {
return min_heap_push_(s, e);
} else {
unsigned parent = (e->ev_timeout_pos.min_heap_idx - 1) / 2;
if (e->ev_timeout_pos.min_heap_idx > 0 && min_heap_elem_greater(s->p[parent], e))
min_heap_shift_up_unconditional_(s, e->ev_timeout_pos.min_heap_idx, e);
else
min_heap_shift_down_(s, e->ev_timeout_pos.min_heap_idx, e);
return 0;
}
}
int min_heap_reserve_(min_heap_t* s, unsigned n)
{
if (s->a < n)
{
struct event** p;
unsigned a = s->a ? s->a * 2 : 8;
if (a < n)
a = n;
if (!(p = (struct event**)mm_realloc(s->p, a * sizeof *p)))
return -1;
s->p = p;
s->a = a;
}
return 0;
}
void min_heap_shift_up_unconditional_(min_heap_t* s, unsigned hole_index, struct event* e)
{
unsigned parent = (hole_index - 1) / 2;
do
{
(s->p[hole_index] = s->p[parent])->ev_timeout_pos.min_heap_idx = hole_index;
hole_index = parent;
parent = (hole_index - 1) / 2;
} while (hole_index && min_heap_elem_greater(s->p[parent], e));
(s->p[hole_index] = e)->ev_timeout_pos.min_heap_idx = hole_index;
}
void min_heap_shift_up_(min_heap_t* s, unsigned hole_index, struct event* e)
{
unsigned parent = (hole_index - 1) / 2;
while (hole_index && min_heap_elem_greater(s->p[parent], e))
{
(s->p[hole_index] = s->p[parent])->ev_timeout_pos.min_heap_idx = hole_index;
hole_index = parent;
parent = (hole_index - 1) / 2;
}
(s->p[hole_index] = e)->ev_timeout_pos.min_heap_idx = hole_index;
}
void min_heap_shift_down_(min_heap_t* s, unsigned hole_index, struct event* e)
{
unsigned min_child = 2 * (hole_index + 1);
while (min_child <= s->n)
{
min_child -= min_child == s->n || min_heap_elem_greater(s->p[min_child], s->p[min_child - 1]);
if (!(min_heap_elem_greater(e, s->p[min_child])))
break;
(s->p[hole_index] = s->p[min_child])->ev_timeout_pos.min_heap_idx = hole_index;
hole_index = min_child;
min_child = 2 * (hole_index + 1);
}
(s->p[hole_index] = e)->ev_timeout_pos.min_heap_idx = hole_index;
}
#endif