get.c
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/**
* \file
*
* \author Georg Hopp
*
* \copyright
* Copyright © 2014 Georg Hopp
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdarg.h>
#include <sys/types.h>
#include "trbase.h"
#include "tr/heap.h"
#include "tr/dynarray.h"
const void *
TR_heapGet(TR_Heap this)
{
const void * value = TR_darrGet((TR_Dynarray)this, 0);
size_t left = 1;
size_t right = 2;
size_t idx;
if (! value) {
return NULL;
}
idx = TR_darrFindFirstFree((TR_Dynarray)this) - 1;
TR_darrGet((TR_Dynarray)this, 0) = NULL;
if (0 == idx) {
return value;
}
SWAP(
void *,
TR_darrGet((TR_Dynarray)this, 0),
TR_darrGet((TR_Dynarray)this, idx));
idx = 0;
while (left < ((TR_Dynarray)this)->size &&
TR_darrGet((TR_Dynarray)this, left)) {
size_t change = left;
if (right < ((TR_Dynarray)this)->size &&
TR_darrGet((TR_Dynarray)this, right) &&
0 > this->comp (
TR_darrGet((TR_Dynarray)this, left),
TR_darrGet((TR_Dynarray)this, right))) {
change = right;
}
if (0 > this->comp(
TR_darrGet((TR_Dynarray)this, idx),
TR_darrGet((TR_Dynarray)this, change))) {
SWAP(
void *,
TR_darrGet((TR_Dynarray)this, idx),
TR_darrGet((TR_Dynarray)this, change));
idx = change;
left = (idx << 1) + 1;
right = left + 1;
} else {
break;
}
}
return value;
}
// vim: set ts=4 sw=4: