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Diffstat (limited to 'lib/lufa/Projects/Magstripe/Lib/CircularBitBuffer.c')
m--------- | lib/lufa | 0 | ||||
-rw-r--r-- | lib/lufa/Projects/Magstripe/Lib/CircularBitBuffer.c | 115 |
2 files changed, 0 insertions, 115 deletions
diff --git a/lib/lufa b/lib/lufa new file mode 160000 +Subproject ce10f7642b0459e409839b23cc91498945119b4 diff --git a/lib/lufa/Projects/Magstripe/Lib/CircularBitBuffer.c b/lib/lufa/Projects/Magstripe/Lib/CircularBitBuffer.c deleted file mode 100644 index 802d040c5b..0000000000 --- a/lib/lufa/Projects/Magstripe/Lib/CircularBitBuffer.c +++ /dev/null @@ -1,115 +0,0 @@ -/* - LUFA Library - Copyright (C) Dean Camera, 2017. - - dean [at] fourwalledcubicle [dot] com - www.lufa-lib.org -*/ - -/* - Copyright 2010 Denver Gingerich (denver [at] ossguy [dot] com) - Copyright 2017 Dean Camera (dean [at] fourwalledcubicle [dot] com) - - Permission to use, copy, modify, distribute, and sell this - software and its documentation for any purpose is hereby granted - without fee, 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 disclaims 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. -*/ - -/** Circular bit buffer library. This will allow for individual bits - * to be stored in packed form inside circular buffers, to reduce - * overall RAM usage. - */ - -#include "CircularBitBuffer.h" - -/** Function to initialize or reset a bit buffer, ready for data to be stored into it. */ -void BitBuffer_Init(BitBuffer_t* const Buffer) -{ - /* Reset the number of stored bits in the buffer */ - Buffer->Elements = 0; - - /* Reset the data in and out pointer structures in the buffer to the first buffer bit */ - Buffer->In.CurrentByte = Buffer->Data; - Buffer->In.ByteMask = (1 << 0); - Buffer->Out.CurrentByte = Buffer->Data; - Buffer->Out.ByteMask = (1 << 0); -} - -/** Function to store the given bit into the given bit buffer. */ -void BitBuffer_StoreNextBit(BitBuffer_t* const Buffer, - const bool Bit) -{ - /* If the bit to store is true, set the next bit in the buffer */ - if (Bit) - *Buffer->In.CurrentByte |= Buffer->In.ByteMask; - - /* Increment the number of stored bits in the buffer counter */ - Buffer->Elements++; - - /* Check if the current buffer byte is full of stored bits */ - if (Buffer->In.ByteMask == (1 << 7)) - { - /* Check if the end of the buffer has been reached, if so reset to start of buffer, otherwise advance to next bit */ - if (Buffer->In.CurrentByte != &Buffer->Data[sizeof(Buffer->Data) - 1]) - Buffer->In.CurrentByte++; - else - Buffer->In.CurrentByte = Buffer->Data; - - /* Reset the storage bit mask in the current buffer byte to the first bit */ - Buffer->In.ByteMask = (1 << 0); - } - else - { - /* Shift the current storage bit mask to the next bit in the current byte */ - Buffer->In.ByteMask <<= 1; - } -} - -/** Function to retrieve the next bit stored in the given bit buffer. */ -bool BitBuffer_GetNextBit(BitBuffer_t* const Buffer) -{ - /* Retrieve the value of the next bit stored in the buffer */ - bool Bit = ((*Buffer->Out.CurrentByte & Buffer->Out.ByteMask) != 0); - - /* Clear the buffer bit */ - *Buffer->Out.CurrentByte &= ~Buffer->Out.ByteMask; - - /* Decrement the number of stored bits in the buffer counter */ - Buffer->Elements--; - - /* Check if the current buffer byte is empty of stored bits */ - if (Buffer->Out.ByteMask == (1 << 7)) - { - /* Check if the end of the buffer has been reached, if so reset to start of buffer, otherwise advance to next bit */ - if (Buffer->Out.CurrentByte != &Buffer->Data[sizeof(Buffer->Data) - 1]) - Buffer->Out.CurrentByte++; - else - Buffer->Out.CurrentByte = Buffer->Data; - - /* Reset the retrieval bit mask in the current buffer byte to the first bit */ - Buffer->Out.ByteMask = (1 << 0); - } - else - { - /* Shift the current retrieval bit mask to the next bit in the current byte */ - Buffer->Out.ByteMask <<= 1; - } - - /* Return the retrieved bit from the buffer */ - return Bit; -} - |