diff options
Diffstat (limited to 'lib/zlib_inflate/infutil.c')
-rw-r--r-- | lib/zlib_inflate/infutil.c | 88 |
1 files changed, 88 insertions, 0 deletions
diff --git a/lib/zlib_inflate/infutil.c b/lib/zlib_inflate/infutil.c new file mode 100644 index 000000000000..00202b3438e1 --- /dev/null +++ b/lib/zlib_inflate/infutil.c | |||
@@ -0,0 +1,88 @@ | |||
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 | } | ||