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/* getbit.h -- bit-buffer access
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This file is part of the UCL data compression library.
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Copyright (C) 1996-2002 Markus Franz Xaver Johannes Oberhumer
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All Rights Reserved.
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The UCL library is free software; you can redistribute it and/or
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modify it under the terms of the GNU General Public License as
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published by the Free Software Foundation; either version 2 of
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the License, or (at your option) any later version.
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The UCL library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with the UCL library; see the file COPYING.
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If not, write to the Free Software Foundation, Inc.,
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59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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Markus F.X.J. Oberhumer
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<markus@oberhumer.com>
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http://www.oberhumer.com/opensource/ucl/
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*/
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/***********************************************************************
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//
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************************************************************************/
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#if 1
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#define getbit_8(bb, src, ilen) \
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(((bb = bb & 0x7f ? bb*2 : ((unsigned)src[ilen++]*2+1)) >> 8) & 1)
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#elif 1
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#define getbit_8(bb, src, ilen) \
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(bb*=2,bb&0xff ? (bb>>8)&1 : ((bb=src[ilen++]*2+1)>>8)&1)
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#else
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#define getbit_8(bb, src, ilen) \
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(((bb*=2, (bb&0xff ? bb : (bb=src[ilen++]*2+1,bb))) >> 8) & 1)
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#endif
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#define getbit_le16(bb, src, ilen) \
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(bb*=2,bb&0xffff ? (bb>>16)&1 : (ilen+=2,((bb=(src[ilen-2]+src[ilen-1]*256u)*2+1)>>16)&1))
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#if 1 && defined(UCL_UNALIGNED_OK_4) && (UCL_BYTE_ORDER == UCL_LITTLE_ENDIAN)
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#define getbit_le32(bb, bc, src, ilen) \
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(bc > 0 ? ((bb>>--bc)&1) : (bc=31,\
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bb=*(const ucl_uint32p)((src)+ilen),ilen+=4,(bb>>31)&1))
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#else
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#define getbit_le32(bb, bc, src, ilen) \
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(bc > 0 ? ((bb>>--bc)&1) : (bc=31,\
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bb=src[ilen]+src[ilen+1]*0x100+src[ilen+2]*UCL_UINT32_C(0x10000)+src[ilen+3]*UCL_UINT32_C(0x1000000),\
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ilen+=4,(bb>>31)&1))
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#endif
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/*
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vi:ts=4:et
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*/
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