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Diffstat (limited to '')
-rw-r--r-- | inflate-0.72.c | 230 |
1 files changed, 230 insertions, 0 deletions
diff --git a/inflate-0.72.c b/inflate-0.72.c new file mode 100644 index 0000000..56b0665 --- /dev/null +++ b/inflate-0.72.c | |||
@@ -0,0 +1,230 @@ | |||
1 | /* inflate.c -- zlib interface to inflate modules | ||
2 | * Copyright (C) 1995 Mark Adler | ||
3 | * For conditions of distribution and use, see copyright notice in zlib.h | ||
4 | */ | ||
5 | |||
6 | #include "zutil.h" | ||
7 | #include "infblock.h" | ||
8 | |||
9 | struct inflate_blocks_state {int dummy;}; /* for buggy compilers */ | ||
10 | |||
11 | /* inflate private state */ | ||
12 | struct internal_state { | ||
13 | |||
14 | /* mode */ | ||
15 | enum { | ||
16 | METHOD, /* waiting for method byte */ | ||
17 | FLAG, /* waiting for flag byte */ | ||
18 | START, /* make new blocks state */ | ||
19 | BLOCKS, /* decompressing blocks */ | ||
20 | CHECK4, /* four check bytes to go */ | ||
21 | CHECK3, /* three check bytes to go */ | ||
22 | CHECK2, /* two check bytes to go */ | ||
23 | CHECK1, /* one check byte to go */ | ||
24 | DONE, /* finished check, done */ | ||
25 | ERROR} /* got an error--stay here */ | ||
26 | mode; /* current inflate mode */ | ||
27 | |||
28 | /* mode dependent information */ | ||
29 | union { | ||
30 | uInt method; /* if FLAGS, method byte */ | ||
31 | struct inflate_blocks_state | ||
32 | *blocks; /* if BLOCKS, current state */ | ||
33 | struct { | ||
34 | uLong was; /* computed check value */ | ||
35 | uLong need; /* stream check value */ | ||
36 | } check; /* if CHECK, check values to compare */ | ||
37 | } sub; /* submode */ | ||
38 | |||
39 | /* mode independent information */ | ||
40 | int nowrap; /* flag for no wrapper */ | ||
41 | uInt wbits; /* log2(window size) (8..15, defaults to 15) */ | ||
42 | |||
43 | }; | ||
44 | |||
45 | |||
46 | int inflateInit(z) | ||
47 | z_stream *z; | ||
48 | { | ||
49 | return inflateInit2(z, WBITS); | ||
50 | } | ||
51 | |||
52 | |||
53 | int inflateInit2(z, w) | ||
54 | z_stream *z; | ||
55 | int w; | ||
56 | { | ||
57 | /* initialize state */ | ||
58 | if (z == Z_NULL) | ||
59 | return Z_STREAM_ERROR; | ||
60 | if (z->zalloc == Z_NULL) z->zalloc = zcalloc; | ||
61 | if (z->zfree == Z_NULL) z->zfree = zcfree; | ||
62 | z->total_in = z->total_out = 0; | ||
63 | z->msg = Z_NULL; | ||
64 | if ((z->state = (struct internal_state *) | ||
65 | ZALLOC(z,1,sizeof(struct internal_state))) == Z_NULL) | ||
66 | return Z_MEM_ERROR; | ||
67 | z->state->mode = METHOD; | ||
68 | |||
69 | /* handle undocumented nowrap option (no zlib header or check) */ | ||
70 | z->state->nowrap = 0; | ||
71 | if (w < 0) | ||
72 | { | ||
73 | w = - w; | ||
74 | z->state->nowrap = 1; | ||
75 | z->state->mode = START; | ||
76 | } | ||
77 | |||
78 | /* set window size */ | ||
79 | if (w < 8 || w > 15) | ||
80 | { | ||
81 | inflateEnd(z); | ||
82 | return Z_STREAM_ERROR; | ||
83 | } | ||
84 | z->state->wbits = w; | ||
85 | return Z_OK; | ||
86 | } | ||
87 | |||
88 | |||
89 | #define NEXTBYTE (z->avail_in--,z->total_in++,*z->next_in++) | ||
90 | |||
91 | int inflate(z, f) | ||
92 | z_stream *z; | ||
93 | int f; | ||
94 | { | ||
95 | int r; | ||
96 | uInt b; | ||
97 | uLong c; | ||
98 | |||
99 | if (z == Z_NULL || z->next_in == Z_NULL) | ||
100 | return Z_STREAM_ERROR; | ||
101 | r = Z_BUF_ERROR; | ||
102 | while (1) switch (z->state->mode) | ||
103 | { | ||
104 | case METHOD: | ||
105 | if (z->avail_in == 0) return r; r = Z_OK; | ||
106 | if (((z->state->sub.method = NEXTBYTE) & 0xf != DEFLATED)) | ||
107 | { | ||
108 | z->state->mode = ERROR; | ||
109 | z->msg = "unknown compression method"; | ||
110 | return Z_DATA_ERROR; | ||
111 | } | ||
112 | if ((z->state->sub.method >> 4) > z->state->wbits) | ||
113 | { | ||
114 | z->state->mode = ERROR; | ||
115 | z->msg = "invalid window size"; | ||
116 | return Z_DATA_ERROR; | ||
117 | } | ||
118 | z->state->mode = FLAG; | ||
119 | case FLAG: | ||
120 | if (z->avail_in == 0) return r; r = Z_OK; | ||
121 | if ((b = NEXTBYTE) & 0x20) | ||
122 | { | ||
123 | z->state->mode = ERROR; | ||
124 | z->msg = "invalid reserved bit"; | ||
125 | return Z_DATA_ERROR; | ||
126 | } | ||
127 | if (((z->state->sub.method << 8) + b) % 31) | ||
128 | { | ||
129 | z->state->mode = ERROR; | ||
130 | z->msg = "incorrect header check"; | ||
131 | return Z_DATA_ERROR; | ||
132 | } | ||
133 | z->state->mode = START; | ||
134 | case START: | ||
135 | if ((z->state->sub.blocks = | ||
136 | inflate_blocks_new(z,1<< z->state->wbits)) == Z_NULL) | ||
137 | return Z_MEM_ERROR; | ||
138 | z->state->mode = BLOCKS; | ||
139 | case BLOCKS: | ||
140 | if ((r = inflate_blocks(z->state->sub.blocks, z, r)) != Z_STREAM_END) | ||
141 | return r; | ||
142 | inflate_blocks_free(z->state->sub.blocks, z, &c, &r); | ||
143 | if (z->state->nowrap) | ||
144 | { | ||
145 | if (r != -1) | ||
146 | z->msg = "inflate bug--took one too many bytes"; | ||
147 | z->state->mode = r == -1 ? DONE : ERROR; | ||
148 | break; | ||
149 | } | ||
150 | z->state->sub.check.was = c; | ||
151 | if (r != -1) | ||
152 | { | ||
153 | z->state->sub.check.need = (uLong)r << 24; | ||
154 | z->state->mode = CHECK3; | ||
155 | r = Z_OK; | ||
156 | break; | ||
157 | } | ||
158 | r = Z_OK; | ||
159 | z->state->mode = CHECK4; | ||
160 | case CHECK4: | ||
161 | if (z->avail_in == 0) return r; r = Z_OK; | ||
162 | z->state->sub.check.need = (uLong)NEXTBYTE << 24; | ||
163 | z->state->mode = CHECK3; | ||
164 | case CHECK3: | ||
165 | if (z->avail_in == 0) return r; r = Z_OK; | ||
166 | z->state->sub.check.need += (uLong)NEXTBYTE << 16; | ||
167 | z->state->mode = CHECK2; | ||
168 | case CHECK2: | ||
169 | if (z->avail_in == 0) return r; r = Z_OK; | ||
170 | z->state->sub.check.need += (uLong)NEXTBYTE << 8; | ||
171 | z->state->mode = CHECK1; | ||
172 | case CHECK1: | ||
173 | if (z->avail_in == 0) return r; r = Z_OK; | ||
174 | z->state->sub.check.need += (uLong)NEXTBYTE; | ||
175 | if (z->state->sub.check.was != z->state->sub.check.need) | ||
176 | { | ||
177 | z->state->mode = ERROR; | ||
178 | z->msg = "incorrect data check"; | ||
179 | return Z_DATA_ERROR; | ||
180 | } | ||
181 | z->state->mode = DONE; | ||
182 | case DONE: | ||
183 | return Z_STREAM_END; | ||
184 | case ERROR: | ||
185 | return Z_DATA_ERROR; | ||
186 | default: | ||
187 | return Z_STREAM_ERROR; | ||
188 | } | ||
189 | } | ||
190 | |||
191 | |||
192 | int inflateEnd(z) | ||
193 | z_stream *z; | ||
194 | { | ||
195 | uLong c; | ||
196 | int e; | ||
197 | |||
198 | if (z == Z_NULL || z->state == Z_NULL || z->zfree == Z_NULL) | ||
199 | return Z_STREAM_ERROR; | ||
200 | if (z->state->mode == BLOCKS) | ||
201 | inflate_blocks_free(z->state->sub.blocks, z, &c, &e); | ||
202 | ZFREE(z, z->state); | ||
203 | z->state = Z_NULL; | ||
204 | return Z_OK; | ||
205 | } | ||
206 | |||
207 | |||
208 | /* inflateSync not implemented yet--this just consumes input */ | ||
209 | int inflateSync(z) | ||
210 | z_stream *z; | ||
211 | { | ||
212 | if (z == Z_NULL) return Z_STREAM_ERROR; | ||
213 | if (z->avail_in == 0) return Z_BUF_ERROR; | ||
214 | do { | ||
215 | z->total_in++; | ||
216 | } while (--z->avail_in); | ||
217 | return Z_DATA_ERROR; | ||
218 | } | ||
219 | |||
220 | |||
221 | /* inflateReset not fully implemented yet--this frees and reallocates */ | ||
222 | int inflateReset(z) | ||
223 | z_stream *z; | ||
224 | { | ||
225 | int r; | ||
226 | |||
227 | if ((r = inflateEnd(z)) != Z_OK) | ||
228 | return r; | ||
229 | return inflateInit(z); | ||
230 | } | ||