lwpa_mempool.h

/******************************************************************************
 * Copyright 2018 ETC Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *******************************************************************************
 * This file is a part of lwpa. For more information, go to:
 * https://github.com/ETCLabs/lwpa
 ******************************************************************************/
 
/* lwpa_mempool.h: Fixed-size memory pools. */
#ifndef _LWPA_MEMPOOL_H_
#define _LWPA_MEMPOOL_H_
 
#include <stddef.h>
#include "lwpa_error.h"
 
typedef struct LwpaMempool LwpaMempool;
struct LwpaMempool
{
  LwpaMempool *next;
};
 
typedef struct LwpaMempoolDesc
{
  const size_t elem_size;  
  const size_t pool_size;  
  LwpaMempool *freelist;   
  LwpaMempool *const list; 
  size_t current_used;
  void *const pool; 
} LwpaMempoolDesc;
 
#define LWPA_MEMPOOL_DECLARE(name) extern LwpaMempoolDesc name##_pool_desc;
 
#define LWPA_MEMPOOL_DEFINE(name, type, size)                                     \
  type name##_pool[size];                                                         \
  struct LwpaMempool name##_pool_list[size];                                      \
  struct LwpaMempoolDesc name##_pool_desc = {sizeof(type),     /* elem_size */    \
                                             size,             /* pool_size */    \
                                             NULL,             /* freelist */     \
                                             name##_pool_list, /* list */         \
                                             0,                /* current_used */ \
                                             name##_pool /* pool */}
 
#define lwpa_mempool_init(name) lwpa_mempool_init_priv(&name##_pool_desc)
 
#define lwpa_mempool_alloc(name) lwpa_mempool_alloc_priv(&name##_pool_desc)
 
#define lwpa_mempool_free(name, mem) lwpa_mempool_free_priv(&name##_pool_desc, mem)
 
#define lwpa_mempool_size(name) (name##_pool_desc.pool_size)
 
#define lwpa_mempool_used(name) lwpa_mempool_used_priv(&name##_pool_desc)
 
#ifdef __cplusplus
extern "C" {
#endif
 
lwpa_error_t lwpa_mempool_init_priv(LwpaMempoolDesc *desc);
void *lwpa_mempool_alloc_priv(LwpaMempoolDesc *desc);
void lwpa_mempool_free_priv(LwpaMempoolDesc *desc, void *elem);
size_t lwpa_mempool_used_priv(LwpaMempoolDesc *desc);
 
#ifdef __cplusplus
}
#endif
 
#endif /* _LWPA_MEMPOOL_H_ */