/* LUFA Library Copyright (C) Dean Camera, 2009. dean [at] fourwalledcubicle [dot] com www.fourwalledcubicle.com */ /* Copyright 2009 Dean Camera (dean [at] fourwalledcubicle [dot] com) Permission to use, copy, modify, and distribute this software and its documentation for any purpose and without fee is hereby granted, provided that the above copyright notice appear in all copies and that both that the copyright notice and this permission notice and warranty disclaimer appear in supporting documentation, and that the name of the author not be used in advertising or publicity pertaining to distribution of the software without specific, written prior permission. The author disclaim all warranties with regard to this software, including all implied warranties of merchantability and fitness. In no event shall the author be liable for any special, indirect or consequential damages or any damages whatsoever resulting from loss of use, data or profits, whether in an action of contract, negligence or other tortious action, arising out of or in connection with the use or performance of this software. */ #include "RingBuff.h" void Buffer_Initialize(RingBuff_t* Buffer) { BUFF_ATOMIC_BLOCK { Buffer->InPtr = (RingBuff_Data_t*)&Buffer->Buffer; Buffer->OutPtr = (RingBuff_Data_t*)&Buffer->Buffer; Buffer->Elements = 0; } } void Buffer_StoreElement(RingBuff_t* Buffer, RingBuff_Data_t Data) { BUFF_ATOMIC_BLOCK { #if defined(BUFF_DROPOLD) if (Buffer->Elements == BUFF_LENGTH) { Buffer->OutPtr++; if (Buffer->OutPtr == &Buffer->Buffer[BUFF_LENGTH]) Buffer->OutPtr = (RingBuff_Data_t*)&Buffer->Buffer; } else { Buffer->Elements++; } #elif defined(BUFF_DROPNEW) if (Buffer->Elements == BUFF_LENGTH) return; Buffer->Elements++; #elif defined(BUFF_NODROPCHECK) Buffer->Elements++; #endif *(Buffer->InPtr) = Data; Buffer->InPtr++; if (Buffer->InPtr == &Buffer->Buffer[BUFF_LENGTH]) Buffer->InPtr = (RingBuff_Data_t*)&Buffer->Buffer; } } RingBuff_Data_t Buffer_GetElement(RingBuff_t* Buffer) { RingBuff_Data_t BuffData; BUFF_ATOMIC_BLOCK { #if defined(BUFF_EMPTYRETURNSZERO) if (!(Buffer->Elements)) return 0; #elif !defined(BUFF_NOEMPTYCHECK) #error No empty buffer check behaviour specified. #endif BuffData = *(Buffer->OutPtr); Buffer->OutPtr++; Buffer->Elements--; if (Buffer->OutPtr == &Buffer->Buffer[BUFF_LENGTH]) Buffer->OutPtr = (RingBuff_Data_t*)&Buffer->Buffer; } return BuffData; } #if defined(BUFF_USEPEEK) RingBuff_Data_t Buffer_PeekElement(const RingBuff_t* Buffer) { RingBuff_Data_t BuffData; BUFF_ATOMIC_BLOCK { #if defined(BUFF_EMPTYRETURNSZERO) if (!(Buffer->Elements)) return 0; #elif !defined(BUFF_NOEMPTYCHECK) #error No empty buffer check behaviour specified. #endif BuffData = *(Buffer->OutPtr); } return BuffData; } #endif