/******************************************************************************
 * Copyright (c) 2022 Telink Semiconductor (Shanghai) Co., Ltd. ("TELINK")
 * All rights reserved.
 *
 * 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.
 *
 *****************************************************************************/
#include "mempool.h"
#include "utility.h"

mem_pool_t *mempool_init(mem_pool_t *pool, void *mem, int itemsize, int itemcount)
{
    if (!pool || !mem) {
        return (0);
    }

    pool->free_list = (mem_block_t *)mem;

    u32 block_size = (u32)(MEMPOOL_ITEMSIZE_2_BLOCKSIZE(itemsize));
    mem_block_t *tmp = (mem_block_t *)mem;
    int i;
    for (i = 0; i < itemcount - 1; ++i) {
        tmp = tmp->next_block = (mem_block_t *)(((u32)tmp) + block_size);
    }
    tmp->next_block = 0;
    return pool;
}

mem_block_t *mempool_header(char *pd)
{
    return (mem_block_t *)(pd - OFFSETOF(mem_block_t, data));
}

void *mempool_alloc(mem_pool_t *pool)
{
    if (!pool->free_list) {
        return 0;
    }

    mem_block_t *tmp = pool->free_list;
    pool->free_list = tmp->next_block;
    return &tmp->data;
}

void mempool_free(mem_pool_t *pool, void *p)
{
    mem_block_t *tmp = mempool_header((char *)p);
    tmp->next_block = pool->free_list;
    pool->free_list = tmp;
}