[3745] | 1 | /**************************************************************************
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| 2 | *
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| 3 | * codesyms.c -- Functions which code the symbol sequence
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| 4 | * Copyright (C) 1994 Hugh Emberson
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| 5 | *
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| 6 | * This program is free software; you can redistribute it and/or modify
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| 7 | * it under the terms of the GNU General Public License as published by
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| 8 | * the Free Software Foundation; either version 2 of the License, or
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| 9 | * (at your option) any later version.
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| 10 | *
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| 11 | * This program is distributed in the hope that it will be useful,
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| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of
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| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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| 14 | * GNU General Public License for more details.
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| 15 | *
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| 16 | * You should have received a copy of the GNU General Public License
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| 17 | * along with this program; if not, write to the Free Software
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| 18 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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| 19 | *
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| 20 | * $Id: codesyms.c 16583 2008-07-29 10:20:36Z davidb $
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| 21 | *
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| 22 | **************************************************************************/
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| 23 |
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| 24 | #include "sysfuncs.h"
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| 25 |
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| 26 | #include "arithcode.h"
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| 27 | #include "marklist.h"
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| 28 | #include "pbmtools.h"
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| 29 | #include "utils.h"
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| 30 | #include "codesyms.h"
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| 31 |
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| 32 | int charsetsize = 256;
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| 33 |
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| 34 | void
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| 35 | EncodeSymbols (marklistptr MarkList, int NSyms)
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| 36 | {
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| 37 | marklistptr step;
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| 38 | unsigned short Events[PPM_CHUNK];
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| 39 | int j = 0;
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| 40 |
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| 41 | charsetsize = max (NSyms, 256);
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| 42 |
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| 43 | step = MarkList;
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| 44 | while (step)
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| 45 | {
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| 46 | Events[j] = step->data.symnum;
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| 47 |
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| 48 | assert (Events[j] > 0 || Events[j] < (unsigned) NSyms);
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| 49 |
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| 50 | j++;
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| 51 |
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| 52 | if (j == PPM_CHUNK)
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| 53 | {
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| 54 | encodestring (Events, PPM_CHUNK);
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| 55 | j = 0;
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| 56 | }
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| 57 | step = step->next;
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| 58 | };
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| 59 |
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| 60 | if (j != 0)
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| 61 | encodestring (Events, j);
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| 62 |
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| 63 | encodestring (Events, 0);
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| 64 | }
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| 65 |
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| 66 |
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| 67 | marklistptr
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| 68 | DecodeSymbols (int NSyms)
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| 69 | {
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| 70 | marklistptr MarkList = NULL;
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| 71 | unsigned short Events[PPM_CHUNK];
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| 72 | int j, n;
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| 73 | marktype d;
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| 74 |
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| 75 | charsetsize = max (NSyms, 256);
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| 76 |
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| 77 | do
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| 78 | {
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| 79 | decodestring (Events, &n);
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| 80 |
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| 81 | for (j = 0; j < n; j++)
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| 82 | {
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| 83 | d.symnum = Events[j];
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| 84 | marklist_add (&MarkList, d);
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| 85 | }
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| 86 | }
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| 87 | while (n != 0);
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| 88 |
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| 89 | return MarkList;
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| 90 | }
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| 91 |
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| 92 | void
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| 93 | InitPPM (void)
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| 94 | {
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| 95 | kbytes = 896;
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| 96 | }
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