| /* 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) 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 LZO package and is subject |
| to change. |
| */ |
| |
| |
| #ifndef __LZO1A_CR_H |
| #define __LZO1A_CR_H |
| |
| |
| /*********************************************************************** |
| // code a literal run |
| ************************************************************************/ |
| |
| static lzo_bytep |
| store_run(lzo_bytep const oo, const lzo_bytep const ii, lzo_uint r_len) |
| { |
| register lzo_bytep op; |
| register const lzo_bytep ip; |
| register 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 */ |
| |
| /* |
| vi:ts=4:et |
| */ |
| |