/* lzo1a_cr.ch -- literal run handling for the the LZO1A 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 LZO package and is subject

   to change.

 */

#ifndef __LZO1A_CR_H

#define __LZO1A_CR_H 1

/***********************************************************************

// code a literal run

************************************************************************/

static lzo_bytep

store_run(lzo_bytep const oo, const lzo_bytep const ii, lzo_uint r_len)

{

    lzo_bytep op;

    const lzo_bytep ip;

    lzo_uint t;

    op = oo;

    ip = ii;

    assert(r_len > 0);

    /* code a long R0 run */

    if (r_len >= 512)

    {

        unsigned r_bits = 6;        /* 256 << 6 == 16384 */

        lzo_uint tt = 32768u;

        while (r_len >= (t = tt))

        {

            r_len -= t;

            *op++ = 0; *op++ = (R0MAX - R0MIN);

            MEMCPY8_DS(op, ip, t);

            LZO_STATS(lzo_stats->r0long_runs++);

        }

        tt >>= 1;

        do {

            if (r_len >= (t = tt))

            {

                r_len -= t;

                *op++ = 0; *op++ = LZO_BYTE((R0FAST - R0MIN) + r_bits);

                MEMCPY8_DS(op, ip, t);

                LZO_STATS(lzo_stats->r0long_runs++);

            }

            tt >>= 1;

        } while (--r_bits > 0);

    }

    assert(r_len < 512);

    while (r_len >= (t = R0FAST))

    {

        r_len -= t;

        *op++ = 0; *op++ = (R0FAST - R0MIN);

        MEMCPY8_DS(op, ip, t);

        LZO_STATS(lzo_stats->r0fast_runs++);

    }

    t = r_len;

    if (t >= R0MIN)

    {

        /* code a short R0 run */

        *op++ = 0; *op++ = LZO_BYTE(t - R0MIN);

        MEMCPY_DS(op, ip, t);

        LZO_STATS(lzo_stats->r0short_runs++);

    }

    else if (t > 0)

    {

        /* code a short literal run */

        LZO_STATS(lzo_stats->lit_runs++);

        LZO_STATS(lzo_stats->lit_run[t]++);

        *op++ = LZO_BYTE(t);

        MEMCPY_DS(op, ip, t);

    }

    return op;

}

#endif /* already included */

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