tinyUSB/tinyusb/common/fifo.h

/*
 * fifo.h
 *
 *  Created on: Nov 27, 2012
 *      Author: hathach
 */

/*
 * Software License Agreement (BSD License)
 * Copyright (c) 2013, hathach (tinyusb.net)
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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 *
 * This file is part of the tinyUSB stack.
 */

/** \file
 *  \brief Error Header
 *
 *  \note TBD
 */

/** \ingroup Group_Common
 *
 *  @{
 */

#ifndef _TUSB_FIFO_H_
#define _TUSB_FIFO_H_

#include "common/common.h"

#ifdef __cplusplus
 extern "C" {
#endif

/** \struct fifo_t
 * \brief Simple Circular FIFO
 */
typedef struct _fifo_t
{
           uint8_t* buf          ; ///< buffer pointer
           uint16_t size         ; ///< buffer size
  volatile uint16_t len          ; ///< bytes in fifo
  volatile uint16_t wr_ptr       ; ///< write pointer
  volatile uint16_t rd_ptr       ; ///< read pointer
           bool     overwritable ; ///< allow overwrite data when full
           IRQn_Type irq         ; ///< TODO (abstract later) interrupt used to lock fifo
} fifo_t;

bool fifo_init(fifo_t* f, uint8_t* buffer, uint16_t size, bool overwritable, IRQn_Type irq);
bool fifo_write(fifo_t* f, uint8_t data);
bool fifo_read(fifo_t* f, uint8_t *data);
uint16_t fifo_read_n(fifo_t* f, uint8_t * rx, uint16_t maxlen);
void fifo_clear(fifo_t *f);

static inline bool fifo_is_empty(fifo_t* f)
{
  return (f->len == 0);
}

static inline bool fifo_is_full(fifo_t* f)
{
  return (f->len == f->size);
}

static inline uint16_t fifo_get_length(fifo_t* f)
{
  return f->len;
}

#ifdef __cplusplus
 }
#endif

#endif /* _TUSB_FIFO_H_ */