/*
 * mem_manager.c
 *
 * Copyright (c) 2008-2016 Ruibang Luo <aquaskyline.com>.
 *
 * This file is part of SOAPdenovo.
 *
 * SOAPdenovo 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.
 *
 * SOAPdenovo 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 SOAPdenovo.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

#include "stdinc.h"
#include "newhash.h"
#include "kmerhash.h"
#include "extfunc.h"
#include "extvab.h"

MEM_MANAGER *createMem_manager ( int num_items, size_t unit_size )
{
  MEM_MANAGER *mem_Manager = ( MEM_MANAGER * ) ckalloc ( 1 * sizeof ( MEM_MANAGER ) );
  mem_Manager->block_list = NULL;
  mem_Manager->items_per_block = num_items;
  mem_Manager->item_size = unit_size;
  mem_Manager->recycle_list = NULL;
  mem_Manager->counter = 0;
  return mem_Manager;
}

void freeMem_manager ( MEM_MANAGER *mem_Manager )
{
  BLOCK_START *ite_block, *temp_block;

  if ( !mem_Manager )
    {
      return;
    }

  ite_block = mem_Manager->block_list;

  while ( ite_block )
    {
      temp_block = ite_block;
      ite_block = ite_block->next;
      free ( ( void * ) temp_block );
    }

  free ( ( void * ) mem_Manager );
}

void *getItem ( MEM_MANAGER *mem_Manager )
{
  RECYCLE_MARK *mark;  //this is the type of return value
  BLOCK_START *block;

  if ( !mem_Manager )
    {
      return NULL;
    }

  if ( mem_Manager->recycle_list )
    {
      mark = mem_Manager->recycle_list;
      mem_Manager->recycle_list = mark->next;
      return mark;
    }

  mem_Manager->counter++;

  if ( !mem_Manager->block_list || mem_Manager->index_in_block == mem_Manager->items_per_block )
    {
      //pthread_mutex_lock(&gmutex);
      block = ckalloc ( sizeof ( BLOCK_START ) + mem_Manager->items_per_block * mem_Manager->item_size );
      //mem_Manager->counter += sizeof(BLOCK_START)+mem_Manager->items_per_block*mem_Manager->item_size;
      //pthread_mutex_unlock(&gmutex);
      block->next = mem_Manager->block_list;
      mem_Manager->block_list = block;
      mem_Manager->index_in_block = 1;
      return ( RECYCLE_MARK * ) ( ( void * ) block + sizeof ( BLOCK_START ) );
    }

  block = mem_Manager->block_list;
  return ( RECYCLE_MARK * ) ( ( void * ) block + sizeof ( BLOCK_START ) + mem_Manager->item_size * ( mem_Manager->index_in_block++ ) );
}

void returnItem ( MEM_MANAGER *mem_Manager, void *item )
{
  RECYCLE_MARK *mark;
  mark = item;
  mark->next = mem_Manager->recycle_list;
  mem_Manager->recycle_list = mark;
}