tinyUSB/tinyusb/common/fifo.h

/**************************************************************************/
/*!
    @file     fifo.h
    @author   hathach (tinyusb.org)

    @section LICENSE

    Software License Agreement (BSD License)

    Copyright (c) 2013, hathach (tinyusb.org)
    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. Neither the name of the copyright holders nor the
    names of its contributors may be used to endorse or promote products
    derived from this software without specific prior written permission.

    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ''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 COPYRIGHT HOLDER 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 CONTRACT, STRICT LIABILITY, OR TORT
    INCLUDING NEGLIGENCE OR OTHERWISE ARISING IN ANY WAY OUT OF THE USE OF THIS
    SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

	  This file is part of the tinyusb stack.
*/
/**************************************************************************/

/** \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
{
           uint8_t* const buffer    ; ///< buffer pointer
           uint16_t const depth     ; ///< max items
           uint16_t const item_size ; ///< size of each item
  volatile uint16_t count           ; ///< number of items in queue
  volatile uint16_t wr_idx          ; ///< write pointer
  volatile uint16_t rd_idx          ; ///< read pointer
           bool overwritable        ;
  // IRQn_Type irq;
} fifo_t;

#define FIFO_DEF(name, ff_depth, type, is_overwritable) /*, irq_mutex)*/ \
  uint8_t name##_buffer[ff_depth*sizeof(type)];\
  fifo_t name = {\
      .buffer       = name##_buffer,\
      .depth        = ff_depth,\
      .item_size    = sizeof(type),\
      .overwritable = is_overwritable,\
      /*.irq          = irq_mutex*/\
  }

bool fifo_write(fifo_t* f, void const * p_data);
bool fifo_read(fifo_t* f, void * p_buffer);
void fifo_clear(fifo_t *f);

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

static inline bool fifo_is_full(fifo_t* f) ATTR_PURE ATTR_ALWAYS_INLINE;
static inline bool fifo_is_full(fifo_t* f)
{
  return (f->count == f->depth);
}

static inline uint16_t fifo_get_length(fifo_t* f) ATTR_PURE ATTR_ALWAYS_INLINE;
static inline uint16_t fifo_get_length(fifo_t* f)
{
  return f->count;
}

#ifdef __cplusplus
 }
#endif

#endif /* _TUSB_FIFO_H_ */