1 #ifndef INFLATE_H 1 #ifndef INFLATE_H
2 #define INFLATE_H 2 #define INFLATE_H
3 3
4 /* inflate.h -- internal inflate state definit 4 /* inflate.h -- internal inflate state definition
5 * Copyright (C) 1995-2004 Mark Adler 5 * Copyright (C) 1995-2004 Mark Adler
6 * For conditions of distribution and use, see 6 * For conditions of distribution and use, see copyright notice in zlib.h
7 */ 7 */
8 8
9 /* WARNING: this file should *not* be used by 9 /* WARNING: this file should *not* be used by applications. It is
10 part of the implementation of the compressi 10 part of the implementation of the compression library and is
11 subject to change. Applications should only 11 subject to change. Applications should only use zlib.h.
12 */ 12 */
13 13
14 #include "inftrees.h" <<
15 <<
16 /* Possible inflate modes between inflate() ca 14 /* Possible inflate modes between inflate() calls */
17 typedef enum { 15 typedef enum {
18 HEAD, /* i: waiting for magic header 16 HEAD, /* i: waiting for magic header */
19 FLAGS, /* i: waiting for method and f 17 FLAGS, /* i: waiting for method and flags (gzip) */
20 TIME, /* i: waiting for modification 18 TIME, /* i: waiting for modification time (gzip) */
21 OS, /* i: waiting for extra flags 19 OS, /* i: waiting for extra flags and operating system (gzip) */
22 EXLEN, /* i: waiting for extra length 20 EXLEN, /* i: waiting for extra length (gzip) */
23 EXTRA, /* i: waiting for extra bytes 21 EXTRA, /* i: waiting for extra bytes (gzip) */
24 NAME, /* i: waiting for end of file 22 NAME, /* i: waiting for end of file name (gzip) */
25 COMMENT, /* i: waiting for end of comme 23 COMMENT, /* i: waiting for end of comment (gzip) */
26 HCRC, /* i: waiting for header crc ( 24 HCRC, /* i: waiting for header crc (gzip) */
27 DICTID, /* i: waiting for dictionary c 25 DICTID, /* i: waiting for dictionary check value */
28 DICT, /* waiting for inflateSetDicti 26 DICT, /* waiting for inflateSetDictionary() call */
29 TYPE, /* i: waiting for type bit 27 TYPE, /* i: waiting for type bits, including last-flag bit */
30 TYPEDO, /* i: same, but skip check 28 TYPEDO, /* i: same, but skip check to exit inflate on new block */
31 STORED, /* i: waiting for stored s 29 STORED, /* i: waiting for stored size (length and complement) */
32 COPY, /* i/o: waiting for input 30 COPY, /* i/o: waiting for input or output to copy stored block */
33 TABLE, /* i: waiting for dynamic 31 TABLE, /* i: waiting for dynamic block table lengths */
34 LENLENS, /* i: waiting for code len 32 LENLENS, /* i: waiting for code length code lengths */
35 CODELENS, /* i: waiting for length/l 33 CODELENS, /* i: waiting for length/lit and distance code lengths */
36 LEN, /* i: waiting for leng 34 LEN, /* i: waiting for length/lit code */
37 LENEXT, /* i: waiting for leng 35 LENEXT, /* i: waiting for length extra bits */
38 DIST, /* i: waiting for dist 36 DIST, /* i: waiting for distance code */
39 DISTEXT, /* i: waiting for dist 37 DISTEXT, /* i: waiting for distance extra bits */
40 MATCH, /* o: waiting for outp 38 MATCH, /* o: waiting for output space to copy string */
41 LIT, /* o: waiting for outp 39 LIT, /* o: waiting for output space to write literal */
42 CHECK, /* i: waiting for 32-bit check 40 CHECK, /* i: waiting for 32-bit check value */
43 LENGTH, /* i: waiting for 32-bit lengt 41 LENGTH, /* i: waiting for 32-bit length (gzip) */
44 DONE, /* finished check, done -- rem 42 DONE, /* finished check, done -- remain here until reset */
45 BAD, /* got a data error -- remain 43 BAD, /* got a data error -- remain here until reset */
46 MEM, /* got an inflate() memory err 44 MEM, /* got an inflate() memory error -- remain here until reset */
47 SYNC /* looking for synchronization 45 SYNC /* looking for synchronization bytes to restart inflate() */
48 } inflate_mode; 46 } inflate_mode;
49 47
50 /* 48 /*
51 State transitions between above modes - 49 State transitions between above modes -
52 50
53 (most modes can go to the BAD or MEM mode 51 (most modes can go to the BAD or MEM mode -- not shown for clarity)
54 52
55 Process header: 53 Process header:
56 HEAD -> (gzip) or (zlib) 54 HEAD -> (gzip) or (zlib)
57 (gzip) -> FLAGS -> TIME -> OS -> EXLEN 55 (gzip) -> FLAGS -> TIME -> OS -> EXLEN -> EXTRA -> NAME
58 NAME -> COMMENT -> HCRC -> TYPE 56 NAME -> COMMENT -> HCRC -> TYPE
59 (zlib) -> DICTID or TYPE 57 (zlib) -> DICTID or TYPE
60 DICTID -> DICT -> TYPE 58 DICTID -> DICT -> TYPE
61 Read deflate blocks: 59 Read deflate blocks:
62 TYPE -> STORED or TABLE or LEN or 60 TYPE -> STORED or TABLE or LEN or CHECK
63 STORED -> COPY -> TYPE 61 STORED -> COPY -> TYPE
64 TABLE -> LENLENS -> CODELENS -> LE 62 TABLE -> LENLENS -> CODELENS -> LEN
65 Read deflate codes: 63 Read deflate codes:
66 LEN -> LENEXT or LIT or TYPE 64 LEN -> LENEXT or LIT or TYPE
67 LENEXT -> DIST -> DISTEXT -> M 65 LENEXT -> DIST -> DISTEXT -> MATCH -> LEN
68 LIT -> LEN 66 LIT -> LEN
69 Process trailer: 67 Process trailer:
70 CHECK -> LENGTH -> DONE 68 CHECK -> LENGTH -> DONE
71 */ 69 */
72 70
73 /* state maintained between inflate() calls. 71 /* state maintained between inflate() calls. Approximately 7K bytes. */
74 struct inflate_state { 72 struct inflate_state {
75 inflate_mode mode; /* current inf 73 inflate_mode mode; /* current inflate mode */
76 int last; /* true if pro 74 int last; /* true if processing last block */
77 int wrap; /* bit 0 true 75 int wrap; /* bit 0 true for zlib, bit 1 true for gzip */
78 int havedict; /* true if dic 76 int havedict; /* true if dictionary provided */
79 int flags; /* gzip header 77 int flags; /* gzip header method and flags (0 if zlib) */
80 unsigned dmax; /* zlib header 78 unsigned dmax; /* zlib header max distance (INFLATE_STRICT) */
81 unsigned long check; /* protected c 79 unsigned long check; /* protected copy of check value */
82 unsigned long total; /* protected c 80 unsigned long total; /* protected copy of output count */
83 /* gz_headerp head; */ /* where t 81 /* gz_headerp head; */ /* where to save gzip header information */
84 /* sliding window */ 82 /* sliding window */
85 unsigned wbits; /* log base 2 83 unsigned wbits; /* log base 2 of requested window size */
86 unsigned wsize; /* window size 84 unsigned wsize; /* window size or zero if not using window */
87 unsigned whave; /* valid bytes 85 unsigned whave; /* valid bytes in the window */
88 unsigned write; /* window writ 86 unsigned write; /* window write index */
89 unsigned char *window; /* allocated slidi 87 unsigned char *window; /* allocated sliding window, if needed */
90 /* bit accumulator */ 88 /* bit accumulator */
91 unsigned long hold; /* input bit a 89 unsigned long hold; /* input bit accumulator */
92 unsigned bits; /* number of b 90 unsigned bits; /* number of bits in "in" */
93 /* for string and stored block copying 91 /* for string and stored block copying */
94 unsigned length; /* literal or 92 unsigned length; /* literal or length of data to copy */
95 unsigned offset; /* distance ba 93 unsigned offset; /* distance back to copy string from */
96 /* for table and code decoding */ 94 /* for table and code decoding */
97 unsigned extra; /* extra bits 95 unsigned extra; /* extra bits needed */
98 /* fixed and dynamic code tables */ 96 /* fixed and dynamic code tables */
99 code const *lencode; /* starting table 97 code const *lencode; /* starting table for length/literal codes */
100 code const *distcode; /* starting table 98 code const *distcode; /* starting table for distance codes */
101 unsigned lenbits; /* index bits 99 unsigned lenbits; /* index bits for lencode */
102 unsigned distbits; /* index bits 100 unsigned distbits; /* index bits for distcode */
103 /* dynamic table building */ 101 /* dynamic table building */
104 unsigned ncode; /* number of c 102 unsigned ncode; /* number of code length code lengths */
105 unsigned nlen; /* number of l 103 unsigned nlen; /* number of length code lengths */
106 unsigned ndist; /* number of d 104 unsigned ndist; /* number of distance code lengths */
107 unsigned have; /* number of c 105 unsigned have; /* number of code lengths in lens[] */
108 code *next; /* next available 106 code *next; /* next available space in codes[] */
109 unsigned short lens[320]; /* temporary s 107 unsigned short lens[320]; /* temporary storage for code lengths */
110 unsigned short work[288]; /* work area f 108 unsigned short work[288]; /* work area for code table building */
111 code codes[ENOUGH]; /* space for c 109 code codes[ENOUGH]; /* space for code tables */
112 }; 110 };
113 <<
114 /* Reverse the bytes in a 32-bit value */ <<
115 #define REVERSE(q) \ <<
116 ((((q) >> 24) & 0xff) + (((q) >> 8) & 0xff <<
117 (((q) & 0xff00) << 8) + (((q) & 0xff) << <<
118 <<
119 #endif 111 #endif
120 112
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.