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QNX/lib/lzo/lzo1c_cc.c
2025-08-20 19:02:58 +08:00

159 lines
3.8 KiB
C

/*
* $QNXtpLicenseC:
* Copyright 2007, QNX Software Systems. All Rights Reserved.
*
* You must obtain a written license from and pay applicable license fees to QNX
* Software Systems before you may reproduce, modify or distribute this software,
* or any work that includes all or part of this software. Free development
* licenses are available for evaluation and non-commercial purposes. For more
* information visit http://licensing.qnx.com or email licensing@qnx.com.
*
* This file may contain contributions from others. Please review this entire
* file for other proprietary rights or license notices, as well as the QNX
* Development Suite License Guide at http://licensing.qnx.com/license-guide/
* for other information.
* $
*/
/* lzo1c_cc.c -- LZO1C compression internal entry point
This file is part of the LZO real-time data compression library.
Copyright (C) 1996-1999 Markus Franz Xaver Johannes Oberhumer
Markus F.X.J. Oberhumer
markus.oberhumer@jk.uni-linz.ac.at
*/
#define LZO_NEED_DICT_H
#include "config1c.h"
/***********************************************************************
// compression internal entry point.
************************************************************************/
int _lzo1c_do_compress ( const lzo_byte *in, lzo_uint in_len,
lzo_byte *out, lzo_uint *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)
_lzo1c_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 = 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_byte *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;
_lzo1c_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 lzo1c_stats = &lzo_statistics;
void _lzo1c_stats_init(lzo_stats_t *lzo_stats)
{
memset(lzo_stats,0,sizeof(*lzo_stats));
}
void _lzo1c_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
*/