Blame src/lzo1b_cr.ch

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/* lzo1b_cr.ch -- implementation of the LZO1B compression algorithm
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   This file is part of the LZO real-time data compression library.
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   Copyright (C) 1996-2014 Markus Franz Xaver Johannes Oberhumer
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   All Rights Reserved.
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   The LZO 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 LZO 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 LZO library; see the file COPYING.
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   If not, write to the Free Software Foundation, Inc.,
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   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, 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/lzo/
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 */
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/* WARNING: this file should *not* be used by applications. It is
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   part of the implementation of the library and is subject
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   to change.
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 */
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/***********************************************************************
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// store the current literal run
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************************************************************************/
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        assert(ip < ip_end);
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        if (pd(ip,ii) > 0)
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        {
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            lzo_uint t = pd(ip,ii);
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#if defined(LZO_HAVE_R1)
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            if (ip == r1)
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            {
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                /* Code a context sensitive R1 match. */
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                LZO_STATS(lzo_stats->literals += t);
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                LZO_STATS(lzo_stats->r1_matches++);
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                assert(t == 1);
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                /* modify marker byte */
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                assert((op[-2] >> M2O_BITS) == (M2_MARKER >> M2O_BITS));
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                op[-2] &= M2O_MASK;
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                assert((op[-2] >> M2O_BITS) == 0);
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                /* copy 1 literal */
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                *op++ = *ii++;
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                r1 = ip + (M2_MIN_LEN + 1);     /* set new R1 pointer */
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            }
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            else
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#endif
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            if (t < R0MIN)
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            {
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                /* inline the copying of a short run */
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                LZO_STATS(lzo_stats->literals += t);
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                LZO_STATS(lzo_stats->lit_runs++);
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                LZO_STATS(lzo_stats->lit_run[t]++);
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#if defined(LZO_HAVE_M3)
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                if (t < LZO_SIZE(8-M3O_BITS) && op == m3)
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                {
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                /* Code a very short literal run into the low offset bits
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                 * of the previous M3/M4 match.
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                 */
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                    LZO_STATS(lzo_stats->lit_runs_after_m3_match++);
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                    LZO_STATS(lzo_stats->lit_run_after_m3_match[t]++);
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                    assert((m3[-2] >> M3O_BITS) == 0);
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                    m3[-2] = LZO_BYTE(m3[-2] | (t << M3O_BITS));
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                }
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                else
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#endif
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                {
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                    *op++ = LZO_BYTE(t);
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                }
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                MEMCPY_DS(op, ii, t);
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#if defined(LZO_HAVE_R1)
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                r1 = ip + (M2_MIN_LEN + 1);     /* set new R1 pointer */
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#endif
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            }
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            else if (t < R0FAST)
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            {
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                /* inline the copying of a short R0 run */
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                LZO_STATS(lzo_stats->literals += t);
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                LZO_STATS(lzo_stats->r0short_runs++);
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                *op++ = 0; *op++ = LZO_BYTE(t - R0MIN);
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                MEMCPY_DS(op, ii, t);
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#if defined(LZO_HAVE_R1)
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                r1 = ip + (M2_MIN_LEN + 1);     /* set new R1 pointer */
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#endif
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            }
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            else
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            {
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                op = STORE_RUN(op,ii,t);
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                ii = ip;
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            }
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        }
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        /* ii now points to the start of the current match */
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        assert(ii == ip);
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/*
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vi:ts=4:et
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*/