Projects/Benito/Lib/RingBuff.h

   1 /*
   2              LUFA Library
   3      Copyright (C) Dean Camera, 2010.
   4
   5   dean [at] fourwalledcubicle [dot] com
   6       www.fourwalledcubicle.com
   7 */
   8
   9 /*
  10   Copyright 2010  Dean Camera (dean [at] fourwalledcubicle [dot] com)
  11
  12   Permission to use, copy, modify, distribute, and sell this
  13   software and its documentation for any purpose is hereby granted
  14   without fee, provided that the above copyright notice appear in
  15   all copies and that both that the copyright notice and this
  16   permission notice and warranty disclaimer appear in supporting
  17   documentation, and that the name of the author not be used in
  18   advertising or publicity pertaining to distribution of the
  19   software without specific, written prior permission.
  20
  21   The author disclaim all warranties with regard to this
  22   software, including all implied warranties of merchantability
  23   and fitness.  In no event shall the author be liable for any
  24   special, indirect or consequential damages or any damages
  25   whatsoever resulting from loss of use, data or profits, whether
  26   in an action of contract, negligence or other tortious action,
  27   arising out of or in connection with the use or performance of
  28   this software.
  29 */
  30
  31 /* Buffer Configuration: */
  32    /* Buffer length - select static size of created ring buffers: */
  33          #define BUFF_STATICSIZE 128      // Set to the static ring buffer size for all ring buffers (place size after define)
  34
  35    /* Volatile mode - uncomment to make buffers volatile, for use in ISRs, etc: */
  36          #define BUFF_VOLATILE            // Uncomment to cause all ring buffers to become volatile (and atomic if multi-byte) in access
  37
  38    /* Drop mode - select behaviour when Buffer_StoreElement called on a full buffer: */
  39      #define BUFF_DROPOLD             // Uncomment to cause full ring buffers to drop the oldest character to make space when full
  40      // #define BUFF_DROPNEW          // Uncomment to cause full ring buffers to drop the new character when full
  41      // #define BUFF_NODROPCHECK      // Uncomment to ignore full ring buffer checks - checking left to user!
  42
  43    /* Underflow behaviour - select behaviour when Buffer_GetElement is called with an empty ring buffer: */
  44      //#define BUFF_EMPTYRETURNSZERO  // Uncomment to return 0 when an empty ring buffer is read
  45      #define BUFF_NOEMPTYCHECK        // Uncomment to disable checking of empty ring buffers - checking left to user!
  46
  47    /* Buffer storage type - set the datatype for the stored data */
  48      #define BUFF_DATATYPE uint8_t    // Change to the data type that is going to be stored into the buffer
  49
  50    /* Peek routine - uncomment to include the peek routine (fetches next byte without removing it from the buffer */
  51      //#define BUFF_USEPEEK
  52
  53 #ifndef _RINGBUFF_H_
  54 #define _RINGBUFF_H_
  55
  56         /* Includes: */
  57         #include <avr/io.h>
  58         #include <avr/interrupt.h>
  59         #include <util/atomic.h>
  60         #include <limits.h>
  61
  62         #include <LUFA/Common/Common.h>
  63
  64         /* Defines and checks: */
  65         #if defined(BUFF_STATICSIZE)
  66                 #define BUFF_LENGTH BUFF_STATICSIZE
  67         #else
  68                 #error No buffer length specified!
  69         #endif
  70
  71         #if !(defined(BUFF_DROPOLD) || defined(BUFF_DROPNEW) || defined(BUFF_NODROPCHECK))
  72                 #error No buffer drop mode specified.
  73         #endif
  74
  75         #if !defined(BUFF_DATATYPE)
  76                 #error Ringbuffer storage data type not specified.
  77         #endif
  78
  79         #if defined(BUFF_VOLATILE)
  80                 #define BUFF_MODE            volatile
  81                 #define BUFF_ATOMIC_BLOCK    ATOMIC_BLOCK(ATOMIC_RESTORESTATE)
  82         #else
  83                 #define BUFF_MODE
  84                 #define BUFF_ATOMIC_BLOCK
  85         #endif
  86
  87         #if (BUFF_STATICSIZE   > LONG_MAX)
  88                 #define RingBuff_Elements_t uint64_t
  89         #elif (BUFF_STATICSIZE > INT_MAX)
  90                 #define RingBuff_Elements_t uint32_t
  91         #elif (BUFF_STATICSIZE > CHAR_MAX)
  92                 #define RingBuff_Elements_t uint16_t
  93         #else
  94                 #define RingBuff_Elements_t uint8_t
  95         #endif
  96
  97         /* Type Defines: */
  98         typedef BUFF_DATATYPE RingBuff_Data_t;
  99
 100         typedef BUFF_MODE struct
 101         {
 102                 RingBuff_Data_t      Buffer[BUFF_LENGTH];
 103                 RingBuff_Data_t*     InPtr;
 104                 RingBuff_Data_t*     OutPtr;
 105                 RingBuff_Elements_t  Elements;
 106         } RingBuff_t;
 107
 108         /* Function Prototypes: */
 109         void            Buffer_Initialize(RingBuff_t* const Buff);
 110         void            Buffer_StoreElement(RingBuff_t* const Buffer, RingBuff_Data_t Data);
 111         RingBuff_Data_t Buffer_GetElement(RingBuff_t* const Buffer);
 112         #if defined(BUFF_USEPEEK)
 113                 RingBuff_Data_t Buffer_PeekElement(const RingBuff_t* const Buffer);
 114         #endif
 115
 116 #endif