ring_buffer.h

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/*
 * @brief Common ring buffer support functions
 *
 * @note
 * Copyright(C) NXP Semiconductors, 2012
 * All rights reserved.
 *
 * @par
 * Software that is described herein is for illustrative purposes only
 * which provides customers with programming information regarding the
 * LPC products.  This software is supplied "AS IS" without any warranties of
 * any kind, and NXP Semiconductors and its licensor disclaim any and
 * all warranties, express or implied, including all implied warranties of
 * merchantability, fitness for a particular purpose and non-infringement of
 * intellectual property rights.  NXP Semiconductors assumes no responsibility
 * or liability for the use of the software, conveys no license or rights under any
 * patent, copyright, mask work right, or any other intellectual property rights in
 * or to any products. NXP Semiconductors reserves the right to make changes
 * in the software without notification. NXP Semiconductors also makes no
 * representation or warranty that such application will be suitable for the
 * specified use without further testing or modification.
 *
 * @par
 * Permission to use, copy, modify, and distribute this software and its
 * documentation is hereby granted, under NXP Semiconductors' and its
 * licensor's relevant copyrights in the software, without fee, provided that it
 * is used in conjunction with NXP Semiconductors microcontrollers.  This
 * copyright, permission, and disclaimer notice must appear in all copies of
 * this code.
 */

#ifndef __RING_BUFFER_H_
#define __RING_BUFFER_H_

#include "lpc_types.h"

typedef struct {
 void *data;
 int count;
 int itemSz;
 uint32_t head;
 uint32_t tail;
 uint32_t valid;
} RINGBUFF_T;


/* Ring buffer validity signature */
#define RB_SIGNATURE              0x51DEF00D

#define RB_VHEAD(rb)              (*(volatile uint32_t *) &(rb)->head)

#define RB_VTAIL(rb)              (*(volatile uint32_t *) &(rb)->tail)

#define RingBuffer_IsValid(rb)     ((rb)->valid == RB_SIGNATURE)

int RingBuffer_Init(RINGBUFF_T *RingBuff, void *buffer, int itemSize, int count);

STATIC INLINE void RingBuffer_Flush(RINGBUFF_T *RingBuff)
{
 RingBuff->head = RingBuff->tail = 0;
}

STATIC INLINE int RingBuffer_GetSize(RINGBUFF_T *RingBuff)
{
 return RingBuff->count;
}

STATIC INLINE int RingBuffer_GetCount(RINGBUFF_T *RingBuff)
{
 return RB_VHEAD(RingBuff) - RB_VTAIL(RingBuff);
}

STATIC INLINE int RingBuffer_GetFree(RINGBUFF_T *RingBuff)
{
 return RingBuff->count - RingBuffer_GetCount(RingBuff);
}

STATIC INLINE int RingBuffer_IsFull(RINGBUFF_T *RingBuff)
{
 return (RingBuffer_GetCount(RingBuff) >= RingBuff->count);
}

STATIC INLINE int RingBuffer_IsEmpty(RINGBUFF_T *RingBuff)
{
 return RB_VHEAD(RingBuff) == RB_VTAIL(RingBuff);
}


int RingBuffer_Insert(RINGBUFF_T *RingBuff, const void *data);

int RingBuffer_InsertMult(RINGBUFF_T *RingBuff, const void *data, int num);

int RingBuffer_Pop(RINGBUFF_T *RingBuff, void *data);

int RingBuffer_PopMult(RINGBUFF_T *RingBuff, void *data, int num);


#endif /* __RING_BUFFER_H_ */