| 1 | /* |
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| 2 | * $Id: //suprahd/releases/suprahd_163/suprahd_ztvapp640_163/drivers/graphics/ZLIB/infutil.c#1 $ |
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| 3 | * $Revision: #1 $ |
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| 4 | * $DateTime: 2006/02/24 17:51:46 $ |
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| 5 | * $Change: 42566 $ |
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| 6 | * $Author: pryush.sharma $ |
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| 7 | */ |
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| 8 | |
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| 9 | /* inflate_util.c -- data and routines common to blocks and codes |
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| 10 | * Copyright (C) 1995-1998 Mark Adler |
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| 11 | * For conditions of distribution and use, see copyright notice in zlib.h |
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| 12 | */ |
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| 13 | |
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| 14 | #include "zutil.h" |
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| 15 | #include "infblock.h" |
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| 16 | #include "inftrees.h" |
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| 17 | #include "infcodes.h" |
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| 18 | #include "infutil.h" |
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| 19 | |
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| 20 | struct inflate_codes_state {int dummy;}; /* for buggy compilers */ |
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| 21 | |
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| 22 | /* And'ing with mask[n] masks the lower n bits */ |
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| 23 | uInt inflate_mask[17] = { |
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| 24 | 0x0000, |
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| 25 | 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff, |
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| 26 | 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff |
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| 27 | }; |
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| 28 | |
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| 29 | |
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| 30 | /* copy as much as possible from the sliding window to the output area */ |
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| 31 | int inflate_flush( |
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| 32 | inflate_blocks_statef *s, |
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| 33 | z_streamp z, |
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| 34 | int r) |
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| 35 | { |
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| 36 | uInt n; |
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| 37 | Bytef *p; |
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| 38 | Bytef *q; |
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| 39 | |
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| 40 | /* local copies of source and destination pointers */ |
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| 41 | p = z->next_out; |
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| 42 | q = s->read; |
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| 43 | |
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| 44 | /* compute number of bytes to copy as far as end of window */ |
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| 45 | n = (uInt)((q <= s->write ? s->write : s->end) - q); |
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| 46 | if (n > z->avail_out) n = z->avail_out; |
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| 47 | if (n && r == Z_BUF_ERROR) r = Z_OK; |
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| 48 | |
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| 49 | /* update counters */ |
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| 50 | z->avail_out -= n; |
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| 51 | z->total_out += n; |
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| 52 | |
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| 53 | /* update check information */ |
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| 54 | if (s->checkfn != Z_NULL) |
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| 55 | z->adler = s->check = (*s->checkfn)(s->check, q, n); |
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| 56 | |
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| 57 | /* copy as far as end of window */ |
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| 58 | zmemcpy(p, q, n); |
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| 59 | p += n; |
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| 60 | q += n; |
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| 61 | |
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| 62 | /* see if more to copy at beginning of window */ |
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| 63 | if (q == s->end) |
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| 64 | { |
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| 65 | /* wrap pointers */ |
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| 66 | q = s->window; |
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| 67 | if (s->write == s->end) |
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| 68 | s->write = s->window; |
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| 69 | |
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| 70 | /* compute bytes to copy */ |
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| 71 | n = (uInt)(s->write - q); |
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| 72 | if (n > z->avail_out) n = z->avail_out; |
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| 73 | if (n && r == Z_BUF_ERROR) r = Z_OK; |
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| 74 | |
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| 75 | /* update counters */ |
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| 76 | z->avail_out -= n; |
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| 77 | z->total_out += n; |
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| 78 | |
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| 79 | /* update check information */ |
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| 80 | if (s->checkfn != Z_NULL) |
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| 81 | z->adler = s->check = (*s->checkfn)(s->check, q, n); |
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| 82 | |
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| 83 | /* copy */ |
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| 84 | zmemcpy(p, q, n); |
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| 85 | p += n; |
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| 86 | q += n; |
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| 87 | } |
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| 88 | |
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| 89 | /* update pointers */ |
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| 90 | z->next_out = p; |
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| 91 | s->read = q; |
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| 92 | |
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| 93 | /* done */ |
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| 94 | return r; |
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| 95 | } |
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