root/trunk/RingBuffAdv/RingBuff.h

/*
                            RING BUFFER LIBRARY
                            By Dean Camera, 2007
*/

// Configuration:

   /* Buffer length - select static size of created ringbuffers: */
         #define BUFF_STATICSIZE 64       // Set to the static ringbuffer size for all ringbuffers (place size after define)

   /* Volatile mode - uncomment to make buffers volatile, for use in ISRs, etc: */
         #define BUFF_VOLATILE            // Uncomment to cause all ring buffers to become volatile (and atomic if multi-byte) in access

   /* Drop mode - select behaviour when Buffer_StoreElement called on a full buffer: */
     #define BUFF_DROPOLD             // Uncomment to cause full ring buffers to drop the oldest character to make space when full
     // #define BUFF_DROPNEW          // Uncomment to cause full ring buffers to drop the new character when full
     // #define BUFF_NODROPCHECK      // Uncomment to ignore full ring buffer checks - checking left to user!

   /* Underflow behaviour - select behaviour when Buffer_GetElement is called with an empty ringbuffer: */
      #define BUFF_EMPTYRETURNSZERO   // Uncomment to return 0 when an empty ringbuffer is read
     //#define BUFF_NOEMPTYCHECK      // Uncomment to disable checking of empty ringbuffers - checking left to user!
        
   /* Buffer storage type - set the datatype for the stored data */
     #define BUFF_DATATYPE uint8_t    // Change to the data type that is going to be stored into the buffer
        
   /* Peek routine - uncomment to include the peek routine (fetches next byte without removing it from the buffer */
     //#define BUFF_USEPEEK
                
#ifndef RINGBUFF_H
#define RINGBUFF_H

        // Includes:
        #include <avr/io.h>
        #include <avr/interrupt.h>
        #include <util/atomic.h>
        #include <limits.h>

        // Defines and Checks:
#if defined(BUFF_STATICSIZE)
        #define BUFF_LENGTH BUFF_STATICSIZE
#else

        #error No buffer length specified!
#endif


#if !(defined(BUFF_DROPOLD) || defined(BUFF_DROPNEW) || defined(BUFF_NODROPCHECK))
        #error No buffer drop mode specified.
#endif


#if !defined(BUFF_DATATYPE)
        #error Ringbuffer storage data type not specified.
#endif


#if defined(BUFF_VOLATILE)
        #define BUFF_MODE volatile
        #define BUFF_ATOMIC_BLOCK ATOMIC_BLOCK(ATOMIC_RESTORESTATE)
#else

        #define BUFF_MODE
        #define BUFF_ATOMIC_BLOCK
#endif


#if (BUFF_STATICSIZE   > LONG_MAX)
        #define RingBuff_Elements_t uint64_t
#elif (BUFF_STATICSIZE > INT_MAX)
        #define RingBuff_Elements_t uint32_t
#elif (BUFF_STATICSIZE > CHAR_MAX)
        #define RingBuff_Elements_t uint16_t
#else

        #define RingBuff_Elements_t uint8_t
#endif

        
        // Type Defines:
        typedef BUFF_DATATYPE RingBuff_Data_t;

        typedef BUFF_MODE struct
        {
                RingBuff_Data_t      Buffer[BUFF_LENGTH];
                RingBuff_Data_t*     InPtr;
                RingBuff_Data_t*     OutPtr;
                RingBuff_Elements_t  Elements;
        } RingBuff_t;
                
        // Prototypes:
        void            Buffer_Initialize(RingBuff_t* Buff);
        void            Buffer_StoreElement(RingBuff_t* Buffer, RingBuff_Data_t Data);
        RingBuff_Data_t Buffer_GetElement(RingBuff_t* Buffer);
#if defined(BUFF_USEPEEK)
        RingBuff_Data_t Buffer_PeekElement(RingBuff_t* Buffer);
#endif

        
#endif