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Diffstat (limited to 'src/lzo_mchw.ch')
| -rw-r--r-- | src/lzo_mchw.ch | 242 |
1 files changed, 242 insertions, 0 deletions
diff --git a/src/lzo_mchw.ch b/src/lzo_mchw.ch new file mode 100644 index 0000000..a8c4fec --- /dev/null +++ b/src/lzo_mchw.ch @@ -0,0 +1,242 @@ +/* lzo_mchw.ch -- matching functions using a window + + 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/ + */ + + +/*********************************************************************** +// +************************************************************************/ + +typedef struct +{ + int init; + + lzo_uint look; /* bytes in lookahead buffer */ + + lzo_uint m_len; + lzo_uint m_off; + + lzo_uint last_m_len; + lzo_uint last_m_off; + + const lzo_bytep bp; + const lzo_bytep ip; + const lzo_bytep in; + const lzo_bytep in_end; + lzo_bytep out; + + lzo_callback_p cb; + + lzo_uint textsize; /* text size counter */ + lzo_uint codesize; /* code size counter */ + lzo_uint printcount; /* counter for reporting progress every 1K bytes */ + + /* some stats */ + unsigned long lit_bytes; + unsigned long match_bytes; + unsigned long rep_bytes; + unsigned long lazy; + +#if defined(LZO1B) + lzo_uint r1_m_len; + + /* some stats */ + unsigned long r1_r, m3_r, m2_m, m3_m; +#endif + +#if defined(LZO1C) + lzo_uint r1_m_len; + lzo_bytep m3; + + /* some stats */ + unsigned long r1_r, m3_r, m2_m, m3_m; +#endif + +#if defined(LZO1F) + lzo_uint r1_lit; + lzo_uint r1_m_len; + + /* some stats */ + unsigned long r1_r, m2_m, m3_m; +#endif + +#if defined(LZO1X) || defined(LZO1Y) || defined(LZO1Z) + lzo_uint r1_lit; + lzo_uint r1_m_len; + + /* some stats */ + unsigned long m1a_m, m1b_m, m2_m, m3_m, m4_m; + unsigned long lit1_r, lit2_r, lit3_r; +#endif + +#if defined(LZO2A) + /* some stats */ + unsigned long m1, m2, m3, m4; +#endif +} +LZO_COMPRESS_T; + + +#if (LZO_CC_BORLANDC && LZO_ARCH_I086) && (__BORLANDC__ < 0x0450) + /* work around a Borland C 3.1 bug */ +# define getbyte(c) ((c).ip < (c).in_end ? (c).ip +=1, (c).ip[-1] : (-1)) +#elif defined(__TURBOC__) && defined(__TOS__) + /* work around a bug in Turbo C / Pure C (Atari ST) */ +# define getbyte(c) ((c).ip < (c).in_end ? (int)(unsigned) *((c).ip)++ : (-1)) +#else +# define getbyte(c) ((c).ip < (c).in_end ? *((c).ip)++ : (-1)) +#endif + +#include "lzo_swd.ch" + + +/*********************************************************************** +// +************************************************************************/ + +static int +init_match ( LZO_COMPRESS_T *c, lzo_swd_p s, + const lzo_bytep dict, lzo_uint dict_len, + lzo_uint32 flags ) +{ + int r; + + assert(!c->init); + c->init = 1; + + s->c = c; + + c->last_m_len = c->last_m_off = 0; + + c->textsize = c->codesize = c->printcount = 0; + c->lit_bytes = c->match_bytes = c->rep_bytes = 0; + c->lazy = 0; + + r = swd_init(s,dict,dict_len); + if (r != 0) + return r; + + s->use_best_off = (flags & 1) ? 1 : 0; + return r; +} + + +/*********************************************************************** +// +************************************************************************/ + +static int +find_match ( LZO_COMPRESS_T *c, lzo_swd_p s, + lzo_uint this_len, lzo_uint skip ) +{ + assert(c->init); + + if (skip > 0) + { + assert(this_len >= skip); + swd_accept(s, this_len - skip); + c->textsize += this_len - skip + 1; + } + else + { + assert(this_len <= 1); + c->textsize += this_len - skip; + } + + s->m_len = 1; + s->m_len = THRESHOLD; +#ifdef SWD_BEST_OFF + if (s->use_best_off) + lzo_memset(s->best_pos,0,sizeof(s->best_pos)); +#endif + swd_findbest(s); + c->m_len = s->m_len; + c->m_off = s->m_off; + + swd_getbyte(s); + + if (s->b_char < 0) + { + c->look = 0; + c->m_len = 0; + swd_exit(s); + } + else + { + c->look = s->look + 1; + } + c->bp = c->ip - c->look; + +#if 0 + /* brute force match search */ + if (c->m_len > THRESHOLD && c->m_len + 1 <= c->look) + { + const lzo_bytep ip = c->bp; + const lzo_bytep m = c->bp - c->m_off; + const lzo_bytep in = c->in; + + if (ip - in > N) + in = ip - N; + for (;;) + { + while (*in != *ip) + in++; + if (in == ip) + break; + if (in != m) + if (lzo_memcmp(in,ip,c->m_len+1) == 0) + printf("%p %p %p %5d\n",in,ip,m,c->m_len); + in++; + } + } +#endif + + if (c->cb && c->cb->nprogress && c->textsize > c->printcount) + { + (*c->cb->nprogress)(c->cb, c->textsize, c->codesize, 0); + c->printcount += 1024; + } + + return LZO_E_OK; +} + + +/* +vi:ts=4:et +*/ + |