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/* lzo1b_cc.c -- LZO1B compression internal entry point
This file is part of the LZO real-time data compression library.
Copyright (C) 2008 Markus Franz Xaver Johannes Oberhumer
Copyright (C) 2007 Markus Franz Xaver Johannes Oberhumer
Copyright (C) 2006 Markus Franz Xaver Johannes Oberhumer
Copyright (C) 2005 Markus Franz Xaver Johannes Oberhumer
Copyright (C) 2004 Markus Franz Xaver Johannes Oberhumer
Copyright (C) 2003 Markus Franz Xaver Johannes Oberhumer
Copyright (C) 2002 Markus Franz Xaver Johannes Oberhumer
Copyright (C) 2001 Markus Franz Xaver Johannes Oberhumer
Copyright (C) 2000 Markus Franz Xaver Johannes Oberhumer
Copyright (C) 1999 Markus Franz Xaver Johannes Oberhumer
Copyright (C) 1998 Markus Franz Xaver Johannes Oberhumer
Copyright (C) 1997 Markus Franz Xaver Johannes Oberhumer
Copyright (C) 1996 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/
*/
#define LZO_NEED_DICT_H
#include "config1b.h"
/***********************************************************************
// compression internal entry point.
************************************************************************/
int _lzo1b_do_compress ( const lzo_bytep in, lzo_uint in_len,
lzo_bytep out, lzo_uintp out_len,
lzo_voidp wrkmem,
lzo_compress_t func )
{
int r;
#if defined(LZO_TEST_COMPRESS_OVERRUN)
lzo_uint avail_out = *out_len;
#endif
#if defined(LZO_COLLECT_STATS)
_lzo1b_stats_init(lzo_stats);
lzo_stats->in_len = in_len;
#endif
/* don't try to compress a block that's too short */
if (in_len <= 0)
{
*out_len = 0;
r = LZO_E_OK;
}
else if (in_len <= MIN_LOOKAHEAD + 1)
{
#if defined(LZO_RETURN_IF_NOT_COMPRESSIBLE)
*out_len = 0;
r = LZO_E_NOT_COMPRESSIBLE;
#else
*out_len = pd(STORE_RUN(out,in,in_len), out);
r = (*out_len > in_len) ? LZO_E_OK : LZO_E_ERROR;
#endif
}
else
r = func(in,in_len,out,out_len,wrkmem);
#if defined(LZO_EOF_CODE)
#if defined(LZO_TEST_COMPRESS_OVERRUN)
if (r == LZO_E_OK && avail_out - *out_len < 3)
r = LZO_E_COMPRESS_OVERRUN;
#endif
if (r == LZO_E_OK)
{
lzo_bytep op = out + *out_len;
*op++ = M3_MARKER | 1;
*op++ = 0;
*op++ = 0;
*out_len += 3;
}
#endif
#if defined(LZO_COLLECT_STATS)
lzo_stats->out_len = *out_len;
lzo_stats->match_bytes =
1 * lzo_stats->m1_matches + 2 * lzo_stats->m2_matches +
3 * lzo_stats->m3_matches + 4 * lzo_stats->m4_matches;
_lzo1b_stats_calc(lzo_stats);
#endif
return r;
}
/***********************************************************************
// note: this is not thread safe, but as it is used for finetuning only
// we don't care
************************************************************************/
#undef lzo_stats
/* lzo_stats_t is still defined */
#if defined(LZO_COLLECT_STATS)
static lzo_stats_t lzo_statistics;
lzo_stats_t * const lzo1b_stats = &lzo_statistics;
void _lzo1b_stats_init(lzo_stats_t *lzo_stats)
{
lzo_memset(lzo_stats,0,sizeof(*lzo_stats));
}
void _lzo1b_stats_calc(lzo_stats_t *lzo_stats)
{
lzo_stats->matches =
lzo_stats->m1_matches + lzo_stats->m2_matches +
lzo_stats->m3_matches + lzo_stats->m4_matches;
lzo_stats->literal_overhead = lzo_stats->lit_runs +
2 * (lzo_stats->r0short_runs + lzo_stats->r0fast_runs +
lzo_stats->r0long_runs);
lzo_stats->literal_bytes = lzo_stats->literals +
lzo_stats->literal_overhead;
#if 0
assert(lzo_stats->match_bytes + lzo_stats->literal_bytes ==
lzo_stats->out_len);
#endif
lzo_stats->m2_matches -= lzo_stats->r1_matches;
lzo_stats->m2_match[M2_MIN_LEN] -= lzo_stats->r1_matches;
if (lzo_stats->literals > 0)
lzo_stats->literal_overhead_percent =
100.0 * lzo_stats->literal_overhead / lzo_stats->literals;
}
#endif
/*
vi:ts=4:et
*/