Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* inflate_util.c -- data and routines common to blocks and codes |
2 | * Copyright (C) 1995-1998 Mark Adler | |
3 | * For conditions of distribution and use, see copyright notice in zlib.h | |
4 | */ | |
5 | ||
6 | #include <linux/zutil.h> | |
7 | #include "infblock.h" | |
8 | #include "inftrees.h" | |
9 | #include "infcodes.h" | |
10 | #include "infutil.h" | |
11 | ||
12 | struct inflate_codes_state; | |
13 | ||
14 | /* And'ing with mask[n] masks the lower n bits */ | |
15 | uInt zlib_inflate_mask[17] = { | |
16 | 0x0000, | |
17 | 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff, | |
18 | 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff | |
19 | }; | |
20 | ||
21 | ||
22 | /* copy as much as possible from the sliding window to the output area */ | |
23 | int zlib_inflate_flush( | |
24 | inflate_blocks_statef *s, | |
25 | z_streamp z, | |
26 | int r | |
27 | ) | |
28 | { | |
29 | uInt n; | |
30 | Byte *p; | |
31 | Byte *q; | |
32 | ||
33 | /* local copies of source and destination pointers */ | |
34 | p = z->next_out; | |
35 | q = s->read; | |
36 | ||
37 | /* compute number of bytes to copy as far as end of window */ | |
38 | n = (uInt)((q <= s->write ? s->write : s->end) - q); | |
39 | if (n > z->avail_out) n = z->avail_out; | |
40 | if (n && r == Z_BUF_ERROR) r = Z_OK; | |
41 | ||
42 | /* update counters */ | |
43 | z->avail_out -= n; | |
44 | z->total_out += n; | |
45 | ||
46 | /* update check information */ | |
47 | if (s->checkfn != NULL) | |
48 | z->adler = s->check = (*s->checkfn)(s->check, q, n); | |
49 | ||
50 | /* copy as far as end of window */ | |
51 | memcpy(p, q, n); | |
52 | p += n; | |
53 | q += n; | |
54 | ||
55 | /* see if more to copy at beginning of window */ | |
56 | if (q == s->end) | |
57 | { | |
58 | /* wrap pointers */ | |
59 | q = s->window; | |
60 | if (s->write == s->end) | |
61 | s->write = s->window; | |
62 | ||
63 | /* compute bytes to copy */ | |
64 | n = (uInt)(s->write - q); | |
65 | if (n > z->avail_out) n = z->avail_out; | |
66 | if (n && r == Z_BUF_ERROR) r = Z_OK; | |
67 | ||
68 | /* update counters */ | |
69 | z->avail_out -= n; | |
70 | z->total_out += n; | |
71 | ||
72 | /* update check information */ | |
73 | if (s->checkfn != NULL) | |
74 | z->adler = s->check = (*s->checkfn)(s->check, q, n); | |
75 | ||
76 | /* copy */ | |
77 | memcpy(p, q, n); | |
78 | p += n; | |
79 | q += n; | |
80 | } | |
81 | ||
82 | /* update pointers */ | |
83 | z->next_out = p; | |
84 | s->read = q; | |
85 | ||
86 | /* done */ | |
87 | return r; | |
88 | } |