Annotation of embedaddon/sudo/zlib/inflate.h, revision 1.1.1.1
1.1 misho 1: /* inflate.h -- internal inflate state definition
2: * Copyright (C) 1995-2009 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: /* define NO_GZIP when compiling if you want to disable gzip header and
12: trailer decoding by inflate(). NO_GZIP would be used to avoid linking in
13: the crc code when it is not needed. For shared libraries, gzip decoding
14: should be left enabled. */
15: #ifndef NO_GZIP
16: # define GUNZIP
17: #endif
18:
19: /* Possible inflate modes between inflate() calls */
20: typedef enum {
21: HEAD, /* i: waiting for magic header */
22: FLAGS, /* i: waiting for method and flags (gzip) */
23: TIME, /* i: waiting for modification time (gzip) */
24: OS, /* i: waiting for extra flags and operating system (gzip) */
25: EXLEN, /* i: waiting for extra length (gzip) */
26: EXTRA, /* i: waiting for extra bytes (gzip) */
27: NAME, /* i: waiting for end of file name (gzip) */
28: COMMENT, /* i: waiting for end of comment (gzip) */
29: HCRC, /* i: waiting for header crc (gzip) */
30: DICTID, /* i: waiting for dictionary check value */
31: DICT, /* waiting for inflateSetDictionary() call */
32: TYPE, /* i: waiting for type bits, including last-flag bit */
33: TYPEDO, /* i: same, but skip check to exit inflate on new block */
34: STORED, /* i: waiting for stored size (length and complement) */
35: COPY_, /* i/o: same as COPY below, but only first time in */
36: COPY, /* i/o: waiting for input or output to copy stored block */
37: TABLE, /* i: waiting for dynamic block table lengths */
38: LENLENS, /* i: waiting for code length code lengths */
39: CODELENS, /* i: waiting for length/lit and distance code lengths */
40: LEN_, /* i: same as LEN below, but only first time in */
41: LEN, /* i: waiting for length/lit/eob code */
42: LENEXT, /* i: waiting for length extra bits */
43: DIST, /* i: waiting for distance code */
44: DISTEXT, /* i: waiting for distance extra bits */
45: MATCH, /* o: waiting for output space to copy string */
46: LIT, /* o: waiting for output space to write literal */
47: CHECK, /* i: waiting for 32-bit check value */
48: LENGTH, /* i: waiting for 32-bit length (gzip) */
49: DONE, /* finished check, done -- remain here until reset */
50: BAD, /* got a data error -- remain here until reset */
51: MEM, /* got an inflate() memory error -- remain here until reset */
52: SYNC /* looking for synchronization bytes to restart inflate() */
53: } inflate_mode;
54:
55: /*
56: State transitions between above modes -
57:
58: (most modes can go to BAD or MEM on error -- not shown for clarity)
59:
60: Process header:
61: HEAD -> (gzip) or (zlib) or (raw)
62: (gzip) -> FLAGS -> TIME -> OS -> EXLEN -> EXTRA -> NAME -> COMMENT ->
63: HCRC -> TYPE
64: (zlib) -> DICTID or TYPE
65: DICTID -> DICT -> TYPE
66: (raw) -> TYPEDO
67: Read deflate blocks:
68: TYPE -> TYPEDO -> STORED or TABLE or LEN_ or CHECK
69: STORED -> COPY_ -> COPY -> TYPE
70: TABLE -> LENLENS -> CODELENS -> LEN_
71: LEN_ -> LEN
72: Read deflate codes in fixed or dynamic block:
73: LEN -> LENEXT or LIT or TYPE
74: LENEXT -> DIST -> DISTEXT -> MATCH -> LEN
75: LIT -> LEN
76: Process trailer:
77: CHECK -> LENGTH -> DONE
78: */
79:
80: /* state maintained between inflate() calls. Approximately 10K bytes. */
81: struct inflate_state {
82: inflate_mode mode; /* current inflate mode */
83: int last; /* true if processing last block */
84: int wrap; /* bit 0 true for zlib, bit 1 true for gzip */
85: int havedict; /* true if dictionary provided */
86: int flags; /* gzip header method and flags (0 if zlib) */
87: unsigned dmax; /* zlib header max distance (INFLATE_STRICT) */
88: unsigned long check; /* protected copy of check value */
89: unsigned long total; /* protected copy of output count */
90: gz_headerp head; /* where to save gzip header information */
91: /* sliding window */
92: unsigned wbits; /* log base 2 of requested window size */
93: unsigned wsize; /* window size or zero if not using window */
94: unsigned whave; /* valid bytes in the window */
95: unsigned wnext; /* window write index */
96: unsigned char FAR *window; /* allocated sliding window, if needed */
97: /* bit accumulator */
98: unsigned long hold; /* input bit accumulator */
99: unsigned bits; /* number of bits in "in" */
100: /* for string and stored block copying */
101: unsigned length; /* literal or length of data to copy */
102: unsigned offset; /* distance back to copy string from */
103: /* for table and code decoding */
104: unsigned extra; /* extra bits needed */
105: /* fixed and dynamic code tables */
106: code const FAR *lencode; /* starting table for length/literal codes */
107: code const FAR *distcode; /* starting table for distance codes */
108: unsigned lenbits; /* index bits for lencode */
109: unsigned distbits; /* index bits for distcode */
110: /* dynamic table building */
111: unsigned ncode; /* number of code length code lengths */
112: unsigned nlen; /* number of length code lengths */
113: unsigned ndist; /* number of distance code lengths */
114: unsigned have; /* number of code lengths in lens[] */
115: code FAR *next; /* next available space in codes[] */
116: unsigned short lens[320]; /* temporary storage for code lengths */
117: unsigned short work[288]; /* work area for code table building */
118: code codes[ENOUGH]; /* space for code tables */
119: int sane; /* if false, allow invalid distance too far */
120: int back; /* bits back of last unprocessed length/lit */
121: unsigned was; /* initial length of match */
122: };
FreeBSD-CVSweb <freebsd-cvsweb@FreeBSD.org>