/*
 * The MIT License (MIT)
 *
 * Copyright (c) 2015 James Ethridge
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of
 * this software and associated documentation files (the "Software"), to deal in
 * the Software without restriction, including without limitation the rights to
 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
 * the Software, and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 */

#ifndef __FifoBuffer_H__
#define __FifoBuffer_H__

#include <os/os.h>
#include <os/mem.h>

#define FifoBuffer_typedef(T, NAME) \
    typedef struct { \
        int size; \
        int start; \
        int end; \
        int write_count;\
        int read_count;\
        T* elems; \
    } NAME

#define FifoBuffer_init(BUF, S, T) \
    BUF->size = S; \
    BUF->start = 0; \
    BUF->end = 0; \
    BUF->read_count=0;\
    BUF->write_count=0;\
    BUF->elems = (T*)os_malloc(S * sizeof(T))

#define FifoBuffer_deinit(BUF) \
    os_free(BUF->elems)

#define FifoBuffer_write(BUF, ELEM)\
    BUF->elems[BUF->end]=ELEM;\
    BUF->write_count++;\
    BUF->end=(BUF->end+1)%BUF->size;

#define FifoBuffer_read(BUF, ELEM)\
    ELEM=BUF->elems[BUF->start];\
    BUF->read_count++;\
    BUF->start=(BUF->start+1)%BUF->size;

#define FifoBuffer_peek(BUF,ELEM,INDEX)\
    ELEM=BUF->elems[BUF->start+INDEX];

#define FifoBuffer_flush(BUF)\
    BUF->start = 0; \
    BUF->end = 0; \
    BUF->read_count=0;\
    BUF->write_count=0;

#define FifoBuffer_count(BUF) (BUF->write_count-BUF->read_count)
#define FifoBuffer_is_full(BUF) (FifoBuffer_count(BUF)==BUF->size)
#define FifoBuffer_is_empty(BUF) (FifoBuffer_count(BUF)==0)
#define FifoBuffer_overflow(BUF) (FifoBuffer_count(BUF)>=BUF->size)

#endif