| 1 |
loizides |
1.1 |
/* lzo1x_oo.ch -- LZO1X compressed data optimizer
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| 2 |
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| 3 |
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This file is part of the LZO real-time data compression library.
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| 4 |
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| 5 |
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Copyright (C) 2008 Markus Franz Xaver Johannes Oberhumer
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| 6 |
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Copyright (C) 2007 Markus Franz Xaver Johannes Oberhumer
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Copyright (C) 2006 Markus Franz Xaver Johannes Oberhumer
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Copyright (C) 2005 Markus Franz Xaver Johannes Oberhumer
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| 9 |
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Copyright (C) 2004 Markus Franz Xaver Johannes Oberhumer
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| 10 |
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Copyright (C) 2003 Markus Franz Xaver Johannes Oberhumer
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| 11 |
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Copyright (C) 2002 Markus Franz Xaver Johannes Oberhumer
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Copyright (C) 2001 Markus Franz Xaver Johannes Oberhumer
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| 13 |
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Copyright (C) 2000 Markus Franz Xaver Johannes Oberhumer
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| 14 |
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Copyright (C) 1999 Markus Franz Xaver Johannes Oberhumer
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| 15 |
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Copyright (C) 1998 Markus Franz Xaver Johannes Oberhumer
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| 16 |
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Copyright (C) 1997 Markus Franz Xaver Johannes Oberhumer
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| 17 |
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Copyright (C) 1996 Markus Franz Xaver Johannes Oberhumer
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| 18 |
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All Rights Reserved.
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| 19 |
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| 20 |
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The LZO library is free software; you can redistribute it and/or
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| 21 |
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modify it under the terms of the GNU General Public License as
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| 22 |
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published by the Free Software Foundation; either version 2 of
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| 23 |
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the License, or (at your option) any later version.
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| 24 |
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| 25 |
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The LZO library is distributed in the hope that it will be useful,
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| 26 |
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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| 27 |
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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| 28 |
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GNU General Public License for more details.
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| 29 |
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| 30 |
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You should have received a copy of the GNU General Public License
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| 31 |
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along with the LZO library; see the file COPYING.
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| 32 |
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If not, write to the Free Software Foundation, Inc.,
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| 33 |
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51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
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| 34 |
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| 35 |
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Markus F.X.J. Oberhumer
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| 36 |
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<markus@oberhumer.com>
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| 37 |
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http://www.oberhumer.com/opensource/lzo/
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| 38 |
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*/
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| 39 |
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| 40 |
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| 41 |
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#define TEST_IP (ip < ip_end)
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| 42 |
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#define TEST_OP (op <= op_end)
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| 43 |
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| 44 |
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#define NO_LIT LZO_UINT_MAX
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| 45 |
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| 46 |
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| 47 |
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/***********************************************************************
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| 48 |
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//
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| 49 |
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************************************************************************/
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| 50 |
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| 51 |
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static void copy2(lzo_bytep ip, const lzo_bytep m_pos, lzo_uint off)
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| 52 |
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{
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| 53 |
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assert(off > 0);
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| 54 |
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ip[0] = m_pos[0];
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| 55 |
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if (off == 1)
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| 56 |
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ip[1] = m_pos[0];
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| 57 |
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else
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| 58 |
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ip[1] = m_pos[1];
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| 59 |
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}
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| 60 |
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| 61 |
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| 62 |
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static void copy3(lzo_bytep ip, const lzo_bytep m_pos, lzo_uint off)
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| 63 |
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{
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| 64 |
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assert(off > 0);
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| 65 |
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ip[0] = m_pos[0];
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| 66 |
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if (off == 1)
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| 67 |
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{
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| 68 |
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ip[2] = ip[1] = m_pos[0];
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| 69 |
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}
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| 70 |
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else if (off == 2)
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| 71 |
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{
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| 72 |
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ip[1] = m_pos[1];
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| 73 |
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ip[2] = m_pos[0];
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| 74 |
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}
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| 75 |
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else
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| 76 |
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{
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| 77 |
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ip[1] = m_pos[1];
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| 78 |
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ip[2] = m_pos[2];
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| 79 |
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}
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| 80 |
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}
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| 81 |
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| 82 |
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| 83 |
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/***********************************************************************
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| 84 |
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// optimize a block of data.
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| 85 |
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************************************************************************/
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| 86 |
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| 87 |
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LZO_PUBLIC(int)
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| 88 |
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DO_OPTIMIZE ( lzo_bytep in , lzo_uint in_len,
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| 89 |
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lzo_bytep out, lzo_uintp out_len,
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| 90 |
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lzo_voidp wrkmem )
|
| 91 |
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{
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| 92 |
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lzo_bytep op;
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| 93 |
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lzo_bytep ip;
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| 94 |
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lzo_uint t;
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| 95 |
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lzo_bytep m_pos;
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| 96 |
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lzo_bytep const ip_end = in + in_len;
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| 97 |
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lzo_bytep const op_end = out + *out_len;
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| 98 |
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lzo_bytep litp = NULL;
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| 99 |
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lzo_uint lit = 0;
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| 100 |
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lzo_uint next_lit = NO_LIT;
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| 101 |
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lzo_uint nl;
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| 102 |
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unsigned long o_m1_a = 0, o_m1_b = 0, o_m2 = 0, o_m3_a = 0, o_m3_b = 0;
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| 103 |
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| 104 |
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LZO_UNUSED(wrkmem);
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| 105 |
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| 106 |
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*out_len = 0;
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| 107 |
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| 108 |
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op = out;
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| 109 |
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ip = in;
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| 110 |
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| 111 |
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assert(in_len >= 3);
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| 112 |
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if (*ip > 17)
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| 113 |
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{
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| 114 |
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t = *ip++ - 17;
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| 115 |
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if (t < 4)
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| 116 |
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goto match_next;
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| 117 |
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goto first_literal_run;
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| 118 |
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}
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| 119 |
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assert(*ip < 16 || (*ip == 17 && in_len == 3));
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| 120 |
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| 121 |
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while (TEST_IP && TEST_OP)
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| 122 |
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{
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| 123 |
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t = *ip++;
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| 124 |
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if (t >= 16)
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| 125 |
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goto match;
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| 126 |
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/* a literal run */
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| 127 |
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litp = ip - 1;
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| 128 |
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if (t == 0)
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| 129 |
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{
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| 130 |
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t = 15;
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| 131 |
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while (*ip == 0)
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| 132 |
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t += 255, ip++;
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| 133 |
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t += *ip++;
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| 134 |
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}
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| 135 |
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lit = t + 3;
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| 136 |
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/* copy literals */
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| 137 |
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copy_literal_run:
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| 138 |
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*op++ = *ip++; *op++ = *ip++; *op++ = *ip++;
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| 139 |
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first_literal_run:
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| 140 |
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do *op++ = *ip++; while (--t > 0);
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| 141 |
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| 142 |
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| 143 |
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t = *ip++;
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| 144 |
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| 145 |
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if (t >= 16)
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| 146 |
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goto match;
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| 147 |
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#if defined(LZO1X)
|
| 148 |
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m_pos = op - 1 - 0x800;
|
| 149 |
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#elif defined(LZO1Y)
|
| 150 |
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m_pos = op - 1 - 0x400;
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| 151 |
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#endif
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| 152 |
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m_pos -= t >> 2;
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| 153 |
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m_pos -= *ip++ << 2;
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| 154 |
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*op++ = *m_pos++; *op++ = *m_pos++; *op++ = *m_pos++;
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| 155 |
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lit = 0;
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| 156 |
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goto match_done;
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| 157 |
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| 158 |
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| 159 |
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/* handle matches */
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| 160 |
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do {
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| 161 |
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if (t < 16) /* a M1 match */
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| 162 |
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{
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| 163 |
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m_pos = op - 1;
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| 164 |
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m_pos -= t >> 2;
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| 165 |
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m_pos -= *ip++ << 2;
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| 166 |
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| 167 |
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if (litp == NULL)
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| 168 |
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goto copy_m1;
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| 169 |
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| 170 |
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/* assert that there was a match just before */
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| 171 |
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assert(lit >= 1 && lit <= 3);
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| 172 |
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assert(litp == ip - 2 - lit - 2);
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| 173 |
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assert((lzo_uint)(*litp & 3) == lit);
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| 174 |
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nl = ip[-2] & 3;
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| 175 |
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/* test if a match follows */
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| 176 |
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if (nl == 0 && lit == 1 && ip[0] >= 16)
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| 177 |
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{
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| 178 |
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next_lit = nl;
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| 179 |
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/* adjust length of previous short run */
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| 180 |
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lit += 2;
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| 181 |
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*litp = LZO_BYTE((*litp & ~3) | lit);
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| 182 |
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/* copy over the 2 literals that replace the match */
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| 183 |
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copy2(ip-2,m_pos,pd(op,m_pos));
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| 184 |
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o_m1_a++;
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| 185 |
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}
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| 186 |
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/* test if a literal run follows */
|
| 187 |
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else if (nl == 0 && ip[0] < 16 && ip[0] != 0 &&
|
| 188 |
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(lit + 2 + ip[0] < 16))
|
| 189 |
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{
|
| 190 |
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t = *ip++;
|
| 191 |
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/* remove short run */
|
| 192 |
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*litp &= ~3;
|
| 193 |
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/* copy over the 2 literals that replace the match */
|
| 194 |
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copy2(ip-3+1,m_pos,pd(op,m_pos));
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| 195 |
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/* move literals 1 byte ahead */
|
| 196 |
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litp += 2;
|
| 197 |
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if (lit > 0)
|
| 198 |
|
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lzo_memmove(litp+1,litp,lit);
|
| 199 |
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/* insert new length of long literal run */
|
| 200 |
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lit += 2 + t + 3; assert(lit <= 18);
|
| 201 |
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*litp = LZO_BYTE(lit - 3);
|
| 202 |
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|
| 203 |
|
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o_m1_b++;
|
| 204 |
|
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*op++ = *m_pos++; *op++ = *m_pos++;
|
| 205 |
|
|
goto copy_literal_run;
|
| 206 |
|
|
}
|
| 207 |
|
|
copy_m1:
|
| 208 |
|
|
*op++ = *m_pos++; *op++ = *m_pos++;
|
| 209 |
|
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}
|
| 210 |
|
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else
|
| 211 |
|
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{
|
| 212 |
|
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match:
|
| 213 |
|
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if (t >= 64) /* a M2 match */
|
| 214 |
|
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{
|
| 215 |
|
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m_pos = op - 1;
|
| 216 |
|
|
#if defined(LZO1X)
|
| 217 |
|
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m_pos -= (t >> 2) & 7;
|
| 218 |
|
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m_pos -= *ip++ << 3;
|
| 219 |
|
|
t = (t >> 5) - 1;
|
| 220 |
|
|
#elif defined(LZO1Y)
|
| 221 |
|
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m_pos -= (t >> 2) & 3;
|
| 222 |
|
|
m_pos -= *ip++ << 2;
|
| 223 |
|
|
t = (t >> 4) - 3;
|
| 224 |
|
|
#endif
|
| 225 |
|
|
if (litp == NULL)
|
| 226 |
|
|
goto copy_m;
|
| 227 |
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|
|
| 228 |
|
|
nl = ip[-2] & 3;
|
| 229 |
|
|
/* test if in beetween two long literal runs */
|
| 230 |
|
|
if (t == 1 && lit > 3 && nl == 0 &&
|
| 231 |
|
|
ip[0] < 16 && ip[0] != 0 && (lit + 3 + ip[0] < 16))
|
| 232 |
|
|
{
|
| 233 |
|
|
assert(*litp == lit - 3);
|
| 234 |
|
|
t = *ip++;
|
| 235 |
|
|
/* copy over the 3 literals that replace the match */
|
| 236 |
|
|
copy3(ip-1-2,m_pos,pd(op,m_pos));
|
| 237 |
|
|
/* set new length of previous literal run */
|
| 238 |
|
|
lit += 3 + t + 3; assert(lit <= 18);
|
| 239 |
|
|
*litp = LZO_BYTE(lit - 3);
|
| 240 |
|
|
o_m2++;
|
| 241 |
|
|
*op++ = *m_pos++; *op++ = *m_pos++; *op++ = *m_pos++;
|
| 242 |
|
|
goto copy_literal_run;
|
| 243 |
|
|
}
|
| 244 |
|
|
}
|
| 245 |
|
|
else
|
| 246 |
|
|
{
|
| 247 |
|
|
if (t >= 32) /* a M3 match */
|
| 248 |
|
|
{
|
| 249 |
|
|
t &= 31;
|
| 250 |
|
|
if (t == 0)
|
| 251 |
|
|
{
|
| 252 |
|
|
t = 31;
|
| 253 |
|
|
while (*ip == 0)
|
| 254 |
|
|
t += 255, ip++;
|
| 255 |
|
|
t += *ip++;
|
| 256 |
|
|
}
|
| 257 |
|
|
m_pos = op - 1;
|
| 258 |
|
|
m_pos -= *ip++ >> 2;
|
| 259 |
|
|
m_pos -= *ip++ << 6;
|
| 260 |
|
|
}
|
| 261 |
|
|
else /* a M4 match */
|
| 262 |
|
|
{
|
| 263 |
|
|
m_pos = op;
|
| 264 |
|
|
m_pos -= (t & 8) << 11;
|
| 265 |
|
|
t &= 7;
|
| 266 |
|
|
if (t == 0)
|
| 267 |
|
|
{
|
| 268 |
|
|
t = 7;
|
| 269 |
|
|
while (*ip == 0)
|
| 270 |
|
|
t += 255, ip++;
|
| 271 |
|
|
t += *ip++;
|
| 272 |
|
|
}
|
| 273 |
|
|
m_pos -= *ip++ >> 2;
|
| 274 |
|
|
m_pos -= *ip++ << 6;
|
| 275 |
|
|
if (m_pos == op)
|
| 276 |
|
|
goto eof_found;
|
| 277 |
|
|
m_pos -= 0x4000;
|
| 278 |
|
|
}
|
| 279 |
|
|
if (litp == NULL)
|
| 280 |
|
|
goto copy_m;
|
| 281 |
|
|
|
| 282 |
|
|
nl = ip[-2] & 3;
|
| 283 |
|
|
/* test if in beetween two matches */
|
| 284 |
|
|
if (t == 1 && lit == 0 && nl == 0 && ip[0] >= 16)
|
| 285 |
|
|
{
|
| 286 |
|
|
assert(litp == ip - 3 - lit - 2);
|
| 287 |
|
|
assert((lzo_uint)(*litp & 3) == lit);
|
| 288 |
|
|
next_lit = nl;
|
| 289 |
|
|
/* make a previous short run */
|
| 290 |
|
|
lit += 3;
|
| 291 |
|
|
*litp = LZO_BYTE((*litp & ~3) | lit);
|
| 292 |
|
|
/* copy over the 3 literals that replace the match */
|
| 293 |
|
|
copy3(ip-3,m_pos,pd(op,m_pos));
|
| 294 |
|
|
o_m3_a++;
|
| 295 |
|
|
}
|
| 296 |
|
|
/* test if a literal run follows */
|
| 297 |
|
|
else if (t == 1 && lit <= 3 && nl == 0 &&
|
| 298 |
|
|
ip[0] < 16 && ip[0] != 0 && (lit + 3 + ip[0] < 16))
|
| 299 |
|
|
{
|
| 300 |
|
|
assert(litp == ip - 3 - lit - 2);
|
| 301 |
|
|
assert((lzo_uint)(*litp & 3) == lit);
|
| 302 |
|
|
t = *ip++;
|
| 303 |
|
|
/* remove short run */
|
| 304 |
|
|
*litp &= ~3;
|
| 305 |
|
|
/* copy over the 3 literals that replace the match */
|
| 306 |
|
|
copy3(ip-4+1,m_pos,pd(op,m_pos));
|
| 307 |
|
|
/* move literals 1 byte ahead */
|
| 308 |
|
|
litp += 2;
|
| 309 |
|
|
if (lit > 0)
|
| 310 |
|
|
lzo_memmove(litp+1,litp,lit);
|
| 311 |
|
|
/* insert new length of long literal run */
|
| 312 |
|
|
lit += 3 + t + 3; assert(lit <= 18);
|
| 313 |
|
|
*litp = LZO_BYTE(lit - 3);
|
| 314 |
|
|
|
| 315 |
|
|
o_m3_b++;
|
| 316 |
|
|
*op++ = *m_pos++; *op++ = *m_pos++; *op++ = *m_pos++;
|
| 317 |
|
|
goto copy_literal_run;
|
| 318 |
|
|
}
|
| 319 |
|
|
}
|
| 320 |
|
|
copy_m:
|
| 321 |
|
|
*op++ = *m_pos++; *op++ = *m_pos++;
|
| 322 |
|
|
do *op++ = *m_pos++; while (--t > 0);
|
| 323 |
|
|
}
|
| 324 |
|
|
|
| 325 |
|
|
match_done:
|
| 326 |
|
|
if (next_lit == NO_LIT)
|
| 327 |
|
|
{
|
| 328 |
|
|
t = ip[-2] & 3;
|
| 329 |
|
|
lit = t;
|
| 330 |
|
|
litp = ip - 2;
|
| 331 |
|
|
}
|
| 332 |
|
|
else
|
| 333 |
|
|
t = next_lit;
|
| 334 |
|
|
assert(t <= 3);
|
| 335 |
|
|
next_lit = NO_LIT;
|
| 336 |
|
|
if (t == 0)
|
| 337 |
|
|
break;
|
| 338 |
|
|
/* copy literals */
|
| 339 |
|
|
match_next:
|
| 340 |
|
|
do *op++ = *ip++; while (--t > 0);
|
| 341 |
|
|
t = *ip++;
|
| 342 |
|
|
} while (TEST_IP && TEST_OP);
|
| 343 |
|
|
}
|
| 344 |
|
|
|
| 345 |
|
|
/* no EOF code was found */
|
| 346 |
|
|
*out_len = pd(op, out);
|
| 347 |
|
|
return LZO_E_EOF_NOT_FOUND;
|
| 348 |
|
|
|
| 349 |
|
|
eof_found:
|
| 350 |
|
|
assert(t == 1);
|
| 351 |
|
|
#if 0
|
| 352 |
|
|
printf("optimize: %5lu %5lu %5lu %5lu %5lu\n",
|
| 353 |
|
|
o_m1_a, o_m1_b, o_m2, o_m3_a, o_m3_b);
|
| 354 |
|
|
#endif
|
| 355 |
|
|
LZO_UNUSED(o_m1_a); LZO_UNUSED(o_m1_b); LZO_UNUSED(o_m2);
|
| 356 |
|
|
LZO_UNUSED(o_m3_a); LZO_UNUSED(o_m3_b);
|
| 357 |
|
|
*out_len = pd(op, out);
|
| 358 |
|
|
return (ip == ip_end ? LZO_E_OK :
|
| 359 |
|
|
(ip < ip_end ? LZO_E_INPUT_NOT_CONSUMED : LZO_E_INPUT_OVERRUN));
|
| 360 |
|
|
}
|
| 361 |
|
|
|
| 362 |
|
|
|
| 363 |
|
|
/*
|
| 364 |
|
|
vi:ts=4:et
|
| 365 |
|
|
*/
|
| 366 |
|
|
|
