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/* lzo1b_cr.ch -- implementation of the LZO1B compression algorithm

   This file is part of the LZO real-time data compression library.

   Copyright (C) 1996-2017 Markus Franz Xaver Johannes Oberhumer
   All Rights Reserved.

   The LZO library 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.

   The LZO library 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 the LZO library; see the file COPYING.
   If not, write to the Free Software Foundation, Inc.,
   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.

   Markus F.X.J. Oberhumer
   <markus@oberhumer.com>
   http://www.oberhumer.com/opensource/lzo/
 */


/* WARNING: this file should *not* be used by applications. It is
   part of the implementation of the library and is subject
   to change.
 */



/***********************************************************************
// store the current literal run
************************************************************************/

        assert(ip < ip_end);
        if (pd(ip,ii) > 0)
        {
            lzo_uint t = pd(ip,ii);

#if defined(LZO_HAVE_R1)
            if (ip == r1)
            {
                /* Code a context sensitive R1 match. */
                LZO_STATS(lzo_stats->literals += t);
                LZO_STATS(lzo_stats->r1_matches++);
                assert(t == 1);
                /* modify marker byte */
                assert((op[-2] >> M2O_BITS) == (M2_MARKER >> M2O_BITS));
                op[-2] &= M2O_MASK;
                assert((op[-2] >> M2O_BITS) == 0);
                /* copy 1 literal */
                *op++ = *ii++;
                r1 = ip + (M2_MIN_LEN + 1);     /* set new R1 pointer */
            }
            else
#endif
            if (t < R0MIN)
            {
                /* inline the copying of a short run */
                LZO_STATS(lzo_stats->literals += t);
                LZO_STATS(lzo_stats->lit_runs++);
                LZO_STATS(lzo_stats->lit_run[t]++);
#if defined(LZO_HAVE_M3)
                if (t < LZO_SIZE(8-M3O_BITS) && op == m3)
                {
                /* Code a very short literal run into the low offset bits
                 * of the previous M3/M4 match.
                 */
                    LZO_STATS(lzo_stats->lit_runs_after_m3_match++);
                    LZO_STATS(lzo_stats->lit_run_after_m3_match[t]++);
                    assert((m3[-2] >> M3O_BITS) == 0);
                    m3[-2] = LZO_BYTE(m3[-2] | (t << M3O_BITS));
                }
                else
#endif
                {
                    *op++ = LZO_BYTE(t);
                }
                MEMCPY_DS(op, ii, t);
#if defined(LZO_HAVE_R1)
                r1 = ip + (M2_MIN_LEN + 1);     /* set new R1 pointer */
#endif
            }
            else if (t < R0FAST)
            {
                /* inline the copying of a short R0 run */
                LZO_STATS(lzo_stats->literals += t);
                LZO_STATS(lzo_stats->r0short_runs++);
                *op++ = 0; *op++ = LZO_BYTE(t - R0MIN);
                MEMCPY_DS(op, ii, t);
#if defined(LZO_HAVE_R1)
                r1 = ip + (M2_MIN_LEN + 1);     /* set new R1 pointer */
#endif
            }
            else
            {
                op = STORE_RUN(op,ii,t);
                ii = ip;
            }
        }


        /* ii now points to the start of the current match */
        assert(ii == ip);


/* vim:set ts=4 sw=4 et: */