diff options
Diffstat (limited to 'PLUGINS/src/dvbhddevice/libhdffcmd/bitbuffer.c')
-rw-r--r-- | PLUGINS/src/dvbhddevice/libhdffcmd/bitbuffer.c | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/PLUGINS/src/dvbhddevice/libhdffcmd/bitbuffer.c b/PLUGINS/src/dvbhddevice/libhdffcmd/bitbuffer.c new file mode 100644 index 0000000..b85990d --- /dev/null +++ b/PLUGINS/src/dvbhddevice/libhdffcmd/bitbuffer.c @@ -0,0 +1,79 @@ +/********************************************************************** + * + * HDFF firmware command interface library + * + * Copyright (C) 2011 Andreas Regel + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the + * Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + * + *********************************************************************/ + +#include <string.h> + +#include "bitbuffer.h" + +void BitBuffer_Init(BitBuffer_t * BitBuffer, + uint8_t * Data, uint32_t MaxLength) +{ + memset(Data, 0, MaxLength); + BitBuffer->Data = Data; + BitBuffer->MaxLength = MaxLength * 8; + BitBuffer->BitPos = 0; +} + +void BitBuffer_SetBits(BitBuffer_t * BitBuffer, int NumBits, uint32_t Data) +{ + uint32_t nextBitPos; + uint32_t bytePos; + uint32_t bitsInByte; + int shift; + + if (NumBits <= 0 || NumBits > 32) + return; + + nextBitPos = BitBuffer->BitPos + NumBits; + + if (nextBitPos > BitBuffer->MaxLength) + return; + + bytePos = BitBuffer->BitPos / 8; + bitsInByte = BitBuffer->BitPos % 8; + + BitBuffer->Data[bytePos] &= (uint8_t) (0xFF << (8 - bitsInByte)); + shift = NumBits - (8 - bitsInByte); + if (shift > 0) + BitBuffer->Data[bytePos] |= (uint8_t) (Data >> shift); + else + BitBuffer->Data[bytePos] |= (uint8_t) (Data << (-shift)); + NumBits -= 8 - bitsInByte; + bytePos++; + while (NumBits > 0) + { + shift = NumBits - 8; + if (shift > 0) + BitBuffer->Data[bytePos] = (uint8_t) (Data >> shift); + else + BitBuffer->Data[bytePos] = (uint8_t) (Data << (-shift)); + NumBits -= 8; + bytePos++; + } + BitBuffer->BitPos = nextBitPos; +} + +uint32_t BitBuffer_GetByteLength(BitBuffer_t * BitBuffer) +{ + return (BitBuffer->BitPos + 7) / 8; +} |