MRPT  1.9.9
inflate.h
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1 /* +------------------------------------------------------------------------+
2  | Mobile Robot Programming Toolkit (MRPT) |
3  | https://www.mrpt.org/ |
4  | |
5  | Copyright (c) 2005-2019, Individual contributors, see AUTHORS file |
6  | See: https://www.mrpt.org/Authors - All rights reserved. |
7  | Released under BSD License. See: https://www.mrpt.org/License |
8  +------------------------------------------------------------------------+ */
9 
10 /* WARNING: this file should *not* be used by applications. It is
11  part of the implementation of the compression library and is
12  subject to change. Applications should only use zlib.h.
13  */
14 
15 /* define NO_GZIP when compiling if you want to disable gzip header and
16  trailer decoding by inflate(). NO_GZIP would be used to avoid linking in
17  the crc code when it is not needed. For shared libraries, gzip decoding
18  should be left enabled. */
19 #ifndef NO_GZIP
20 #define GUNZIP
21 #endif
22 
23 /* Possible inflate modes between inflate() calls */
24 typedef enum
25 {
26  HEAD, /* i: waiting for magic header */
27  FLAGS, /* i: waiting for method and flags (gzip) */
28  TIME, /* i: waiting for modification time (gzip) */
29  OS, /* i: waiting for extra flags and operating system (gzip) */
30  EXLEN, /* i: waiting for extra length (gzip) */
31  EXTRA, /* i: waiting for extra bytes (gzip) */
32  NAME, /* i: waiting for end of file name (gzip) */
33  COMMENT, /* i: waiting for end of comment (gzip) */
34  HCRC, /* i: waiting for header crc (gzip) */
35  DICTID, /* i: waiting for dictionary check value */
36  DICT, /* waiting for inflateSetDictionary() call */
37  TYPE, /* i: waiting for type bits, including last-flag bit */
38  TYPEDO, /* i: same, but skip check to exit inflate on new block */
39  STORED, /* i: waiting for stored size (length and complement) */
40  COPY, /* i/o: waiting for input or output to copy stored block */
41  TABLE, /* i: waiting for dynamic block table lengths */
42  LENLENS, /* i: waiting for code length code lengths */
43  CODELENS, /* i: waiting for length/lit and distance code lengths */
44  LEN, /* i: waiting for length/lit code */
45  LENEXT, /* i: waiting for length extra bits */
46  DIST, /* i: waiting for distance code */
47  DISTEXT, /* i: waiting for distance extra bits */
48  MATCH, /* o: waiting for output space to copy string */
49  LIT, /* o: waiting for output space to write literal */
50  CHECK, /* i: waiting for 32-bit check value */
51  LENGTH, /* i: waiting for 32-bit length (gzip) */
52  DONE, /* finished check, done -- remain here until reset */
53  BAD, /* got a data error -- remain here until reset */
54  MEM, /* got an inflate() memory error -- remain here until reset */
55  SYNC /* looking for synchronization bytes to restart inflate() */
56 } inflate_mode;
57 
58 /*
59  State transitions between above modes -
60 
61  (most modes can go to the BAD or MEM mode -- not shown for clarity)
62 
63  Process header:
64  HEAD -> (gzip) or (zlib)
65  (gzip) -> FLAGS -> TIME -> OS -> EXLEN -> EXTRA -> NAME
66  NAME -> COMMENT -> HCRC -> TYPE
67  (zlib) -> DICTID or TYPE
68  DICTID -> DICT -> TYPE
69  Read deflate blocks:
70  TYPE -> STORED or TABLE or LEN or CHECK
71  STORED -> COPY -> TYPE
72  TABLE -> LENLENS -> CODELENS -> LEN
73  Read deflate codes:
74  LEN -> LENEXT or LIT or TYPE
75  LENEXT -> DIST -> DISTEXT -> MATCH -> LEN
76  LIT -> LEN
77  Process trailer:
78  CHECK -> LENGTH -> DONE
79  */
80 
81 /* state maintained between inflate() calls. Approximately 7K bytes. */
83 {
84  inflate_mode mode; /* current inflate mode */
85  int last; /* true if processing last block */
86  int wrap; /* bit 0 true for zlib, bit 1 true for gzip */
87  int havedict; /* true if dictionary provided */
88  int flags; /* gzip header method and flags (0 if zlib) */
89  unsigned dmax; /* zlib header max distance (INFLATE_STRICT) */
90  unsigned long check; /* protected copy of check value */
91  unsigned long total; /* protected copy of output count */
92  gz_headerp head; /* where to save gzip header information */
93  /* sliding window */
94  unsigned wbits; /* log base 2 of requested window size */
95  unsigned wsize; /* window size or zero if not using window */
96  unsigned whave; /* valid bytes in the window */
97  unsigned write; /* window write index */
98  unsigned char FAR* window; /* allocated sliding window, if needed */
99  /* bit accumulator */
100  unsigned long hold; /* input bit accumulator */
101  unsigned bits; /* number of bits in "in" */
102  /* for string and stored block copying */
103  unsigned length; /* literal or length of data to copy */
104  unsigned offset; /* distance back to copy string from */
105  /* for table and code decoding */
106  unsigned extra; /* extra bits needed */
107  /* fixed and dynamic code tables */
108  code const FAR* lencode; /* starting table for length/literal codes */
109  code const FAR* distcode; /* starting table for distance codes */
110  unsigned lenbits; /* index bits for lencode */
111  unsigned distbits; /* index bits for distcode */
112  /* dynamic table building */
113  unsigned ncode; /* number of code length code lengths */
114  unsigned nlen; /* number of length code lengths */
115  unsigned ndist; /* number of distance code lengths */
116  unsigned have; /* number of code lengths in lens[] */
117  code FAR* next; /* next available space in codes[] */
118  unsigned short lens[320]; /* temporary storage for code lengths */
119  unsigned short work[288]; /* work area for code table building */
120  code codes[ENOUGH]; /* space for code tables */
121 };
unsigned nlen
Definition: inflate.h:114
Definition: inflate.h:40
int havedict
Definition: inflate.h:87
Definition: inflate.h:39
unsigned ndist
Definition: inflate.h:115
unsigned long total
Definition: inflate.h:91
gz_headerp head
Definition: inflate.h:92
unsigned wsize
Definition: inflate.h:95
unsigned have
Definition: inflate.h:116
unsigned distbits
Definition: inflate.h:111
#define ENOUGH
Definition: inftrees.h:48
unsigned extra
Definition: inflate.h:106
code const FAR * distcode
Definition: inflate.h:109
unsigned long check
Definition: inflate.h:90
Definition: inflate.h:52
Definition: inflate.h:32
Definition: inflate.h:37
Definition: inflate.h:35
gz_header FAR * gz_headerp
Definition: zlib.h:110
Definition: inflate.h:29
unsigned lenbits
Definition: inflate.h:110
unsigned short lens[320]
Definition: inflate.h:118
Definition: inflate.h:44
unsigned ncode
Definition: inflate.h:113
Definition: inflate.h:41
Definition: inflate.h:51
code FAR * next
Definition: inflate.h:117
Definition: inflate.h:55
Definition: inflate.h:31
code codes[ENOUGH]
Definition: inflate.h:120
unsigned long hold
Definition: inflate.h:100
Definition: inflate.h:50
Definition: inflate.h:45
Definition: inflate.h:49
Definition: inflate.h:28
Definition: inflate.h:36
unsigned short work[288]
Definition: inflate.h:119
Definition: inflate.h:34
Definition: inflate.h:26
unsigned write
Definition: inflate.h:97
Definition: inftrees.h:28
unsigned dmax
Definition: inflate.h:89
unsigned bits
Definition: inflate.h:101
Definition: inflate.h:48
Definition: inflate.h:38
inflate_mode
Definition: inflate.h:24
Definition: inflate.h:30
unsigned char FAR * window
Definition: inflate.h:98
inflate_mode mode
Definition: inflate.h:84
Definition: inflate.h:53
unsigned whave
Definition: inflate.h:96
#define FAR
Definition: zconf.h:261
unsigned offset
Definition: inflate.h:104
Definition: inflate.h:46
code const FAR * lencode
Definition: inflate.h:108
Definition: inflate.h:27
unsigned wbits
Definition: inflate.h:94
Definition: inflate.h:54
unsigned length
Definition: inflate.h:103



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