| /* lzo1b_cr.ch -- implementation of the LZO1B compression algorithm |
| |
| 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/ |
| */ |
| |
| |
| /* 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(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); |
| |
| |
| /* |
| vi:ts=4:et |
| */ |
