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Diffstat (limited to 'lib/zlib_inflate/inflate.h')
-rw-r--r-- | lib/zlib_inflate/inflate.h | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/lib/zlib_inflate/inflate.h b/lib/zlib_inflate/inflate.h new file mode 100644 index 000000000000..df8a6c92052d --- /dev/null +++ b/lib/zlib_inflate/inflate.h | |||
@@ -0,0 +1,107 @@ | |||
1 | /* inflate.h -- internal inflate state definition | ||
2 | * Copyright (C) 1995-2004 Mark Adler | ||
3 | * For conditions of distribution and use, see copyright notice in zlib.h | ||
4 | */ | ||
5 | |||
6 | /* WARNING: this file should *not* be used by applications. It is | ||
7 | part of the implementation of the compression library and is | ||
8 | subject to change. Applications should only use zlib.h. | ||
9 | */ | ||
10 | |||
11 | /* Possible inflate modes between inflate() calls */ | ||
12 | typedef enum { | ||
13 | HEAD, /* i: waiting for magic header */ | ||
14 | FLAGS, /* i: waiting for method and flags (gzip) */ | ||
15 | TIME, /* i: waiting for modification time (gzip) */ | ||
16 | OS, /* i: waiting for extra flags and operating system (gzip) */ | ||
17 | EXLEN, /* i: waiting for extra length (gzip) */ | ||
18 | EXTRA, /* i: waiting for extra bytes (gzip) */ | ||
19 | NAME, /* i: waiting for end of file name (gzip) */ | ||
20 | COMMENT, /* i: waiting for end of comment (gzip) */ | ||
21 | HCRC, /* i: waiting for header crc (gzip) */ | ||
22 | DICTID, /* i: waiting for dictionary check value */ | ||
23 | DICT, /* waiting for inflateSetDictionary() call */ | ||
24 | TYPE, /* i: waiting for type bits, including last-flag bit */ | ||
25 | TYPEDO, /* i: same, but skip check to exit inflate on new block */ | ||
26 | STORED, /* i: waiting for stored size (length and complement) */ | ||
27 | COPY, /* i/o: waiting for input or output to copy stored block */ | ||
28 | TABLE, /* i: waiting for dynamic block table lengths */ | ||
29 | LENLENS, /* i: waiting for code length code lengths */ | ||
30 | CODELENS, /* i: waiting for length/lit and distance code lengths */ | ||
31 | LEN, /* i: waiting for length/lit code */ | ||
32 | LENEXT, /* i: waiting for length extra bits */ | ||
33 | DIST, /* i: waiting for distance code */ | ||
34 | DISTEXT, /* i: waiting for distance extra bits */ | ||
35 | MATCH, /* o: waiting for output space to copy string */ | ||
36 | LIT, /* o: waiting for output space to write literal */ | ||
37 | CHECK, /* i: waiting for 32-bit check value */ | ||
38 | LENGTH, /* i: waiting for 32-bit length (gzip) */ | ||
39 | DONE, /* finished check, done -- remain here until reset */ | ||
40 | BAD, /* got a data error -- remain here until reset */ | ||
41 | MEM, /* got an inflate() memory error -- remain here until reset */ | ||
42 | SYNC /* looking for synchronization bytes to restart inflate() */ | ||
43 | } inflate_mode; | ||
44 | |||
45 | /* | ||
46 | State transitions between above modes - | ||
47 | |||
48 | (most modes can go to the BAD or MEM mode -- not shown for clarity) | ||
49 | |||
50 | Process header: | ||
51 | HEAD -> (gzip) or (zlib) | ||
52 | (gzip) -> FLAGS -> TIME -> OS -> EXLEN -> EXTRA -> NAME | ||
53 | NAME -> COMMENT -> HCRC -> TYPE | ||
54 | (zlib) -> DICTID or TYPE | ||
55 | DICTID -> DICT -> TYPE | ||
56 | Read deflate blocks: | ||
57 | TYPE -> STORED or TABLE or LEN or CHECK | ||
58 | STORED -> COPY -> TYPE | ||
59 | TABLE -> LENLENS -> CODELENS -> LEN | ||
60 | Read deflate codes: | ||
61 | LEN -> LENEXT or LIT or TYPE | ||
62 | LENEXT -> DIST -> DISTEXT -> MATCH -> LEN | ||
63 | LIT -> LEN | ||
64 | Process trailer: | ||
65 | CHECK -> LENGTH -> DONE | ||
66 | */ | ||
67 | |||
68 | /* state maintained between inflate() calls. Approximately 7K bytes. */ | ||
69 | struct inflate_state { | ||
70 | inflate_mode mode; /* current inflate mode */ | ||
71 | int last; /* true if processing last block */ | ||
72 | int wrap; /* bit 0 true for zlib, bit 1 true for gzip */ | ||
73 | int havedict; /* true if dictionary provided */ | ||
74 | int flags; /* gzip header method and flags (0 if zlib) */ | ||
75 | unsigned dmax; /* zlib header max distance (INFLATE_STRICT) */ | ||
76 | unsigned long check; /* protected copy of check value */ | ||
77 | unsigned long total; /* protected copy of output count */ | ||
78 | /* gz_headerp head; */ /* where to save gzip header information */ | ||
79 | /* sliding window */ | ||
80 | unsigned wbits; /* log base 2 of requested window size */ | ||
81 | unsigned wsize; /* window size or zero if not using window */ | ||
82 | unsigned whave; /* valid bytes in the window */ | ||
83 | unsigned write; /* window write index */ | ||
84 | unsigned char *window; /* allocated sliding window, if needed */ | ||
85 | /* bit accumulator */ | ||
86 | unsigned long hold; /* input bit accumulator */ | ||
87 | unsigned bits; /* number of bits in "in" */ | ||
88 | /* for string and stored block copying */ | ||
89 | unsigned length; /* literal or length of data to copy */ | ||
90 | unsigned offset; /* distance back to copy string from */ | ||
91 | /* for table and code decoding */ | ||
92 | unsigned extra; /* extra bits needed */ | ||
93 | /* fixed and dynamic code tables */ | ||
94 | code const *lencode; /* starting table for length/literal codes */ | ||
95 | code const *distcode; /* starting table for distance codes */ | ||
96 | unsigned lenbits; /* index bits for lencode */ | ||
97 | unsigned distbits; /* index bits for distcode */ | ||
98 | /* dynamic table building */ | ||
99 | unsigned ncode; /* number of code length code lengths */ | ||
100 | unsigned nlen; /* number of length code lengths */ | ||
101 | unsigned ndist; /* number of distance code lengths */ | ||
102 | unsigned have; /* number of code lengths in lens[] */ | ||
103 | code *next; /* next available space in codes[] */ | ||
104 | unsigned short lens[320]; /* temporary storage for code lengths */ | ||
105 | unsigned short work[288]; /* work area for code table building */ | ||
106 | code codes[ENOUGH]; /* space for code tables */ | ||
107 | }; | ||