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6#include <linux/zutil.h>
7#include "inftrees.h"
8#include "inflate.h"
9#include "inffast.h"
10
11#ifndef ASMINF
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24#ifdef POSTINC
25# define OFF 0
26# define PUP(a) *(a)++
27#else
28# define OFF 1
29# define PUP(a) *++(a)
30#endif
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69void inflate_fast(z_streamp strm, unsigned start)
70{
71 struct inflate_state *state;
72 const unsigned char *in;
73 const unsigned char *last;
74 unsigned char *out;
75 unsigned char *beg;
76 unsigned char *end;
77#ifdef INFLATE_STRICT
78 unsigned dmax;
79#endif
80 unsigned wsize;
81 unsigned whave;
82 unsigned write;
83 unsigned char *window;
84 unsigned long hold;
85 unsigned bits;
86 code const *lcode;
87 code const *dcode;
88 unsigned lmask;
89 unsigned dmask;
90 code this;
91 unsigned op;
92
93 unsigned len;
94 unsigned dist;
95 unsigned char *from;
96
97
98 state = (struct inflate_state *)strm->state;
99 in = strm->next_in - OFF;
100 last = in + (strm->avail_in - 5);
101 out = strm->next_out - OFF;
102 beg = out - (start - strm->avail_out);
103 end = out + (strm->avail_out - 257);
104#ifdef INFLATE_STRICT
105 dmax = state->dmax;
106#endif
107 wsize = state->wsize;
108 whave = state->whave;
109 write = state->write;
110 window = state->window;
111 hold = state->hold;
112 bits = state->bits;
113 lcode = state->lencode;
114 dcode = state->distcode;
115 lmask = (1U << state->lenbits) - 1;
116 dmask = (1U << state->distbits) - 1;
117
118
119
120 do {
121 if (bits < 15) {
122 hold += (unsigned long)(PUP(in)) << bits;
123 bits += 8;
124 hold += (unsigned long)(PUP(in)) << bits;
125 bits += 8;
126 }
127 this = lcode[hold & lmask];
128 dolen:
129 op = (unsigned)(this.bits);
130 hold >>= op;
131 bits -= op;
132 op = (unsigned)(this.op);
133 if (op == 0) {
134 PUP(out) = (unsigned char)(this.val);
135 }
136 else if (op & 16) {
137 len = (unsigned)(this.val);
138 op &= 15;
139 if (op) {
140 if (bits < op) {
141 hold += (unsigned long)(PUP(in)) << bits;
142 bits += 8;
143 }
144 len += (unsigned)hold & ((1U << op) - 1);
145 hold >>= op;
146 bits -= op;
147 }
148 if (bits < 15) {
149 hold += (unsigned long)(PUP(in)) << bits;
150 bits += 8;
151 hold += (unsigned long)(PUP(in)) << bits;
152 bits += 8;
153 }
154 this = dcode[hold & dmask];
155 dodist:
156 op = (unsigned)(this.bits);
157 hold >>= op;
158 bits -= op;
159 op = (unsigned)(this.op);
160 if (op & 16) {
161 dist = (unsigned)(this.val);
162 op &= 15;
163 if (bits < op) {
164 hold += (unsigned long)(PUP(in)) << bits;
165 bits += 8;
166 if (bits < op) {
167 hold += (unsigned long)(PUP(in)) << bits;
168 bits += 8;
169 }
170 }
171 dist += (unsigned)hold & ((1U << op) - 1);
172#ifdef INFLATE_STRICT
173 if (dist > dmax) {
174 strm->msg = (char *)"invalid distance too far back";
175 state->mode = BAD;
176 break;
177 }
178#endif
179 hold >>= op;
180 bits -= op;
181 op = (unsigned)(out - beg);
182 if (dist > op) {
183 op = dist - op;
184 if (op > whave) {
185 strm->msg = (char *)"invalid distance too far back";
186 state->mode = BAD;
187 break;
188 }
189 from = window - OFF;
190 if (write == 0) {
191 from += wsize - op;
192 if (op < len) {
193 len -= op;
194 do {
195 PUP(out) = PUP(from);
196 } while (--op);
197 from = out - dist;
198 }
199 }
200 else if (write < op) {
201 from += wsize + write - op;
202 op -= write;
203 if (op < len) {
204 len -= op;
205 do {
206 PUP(out) = PUP(from);
207 } while (--op);
208 from = window - OFF;
209 if (write < len) {
210 op = write;
211 len -= op;
212 do {
213 PUP(out) = PUP(from);
214 } while (--op);
215 from = out - dist;
216 }
217 }
218 }
219 else {
220 from += write - op;
221 if (op < len) {
222 len -= op;
223 do {
224 PUP(out) = PUP(from);
225 } while (--op);
226 from = out - dist;
227 }
228 }
229 while (len > 2) {
230 PUP(out) = PUP(from);
231 PUP(out) = PUP(from);
232 PUP(out) = PUP(from);
233 len -= 3;
234 }
235 if (len) {
236 PUP(out) = PUP(from);
237 if (len > 1)
238 PUP(out) = PUP(from);
239 }
240 }
241 else {
242 from = out - dist;
243 do {
244 PUP(out) = PUP(from);
245 PUP(out) = PUP(from);
246 PUP(out) = PUP(from);
247 len -= 3;
248 } while (len > 2);
249 if (len) {
250 PUP(out) = PUP(from);
251 if (len > 1)
252 PUP(out) = PUP(from);
253 }
254 }
255 }
256 else if ((op & 64) == 0) {
257 this = dcode[this.val + (hold & ((1U << op) - 1))];
258 goto dodist;
259 }
260 else {
261 strm->msg = (char *)"invalid distance code";
262 state->mode = BAD;
263 break;
264 }
265 }
266 else if ((op & 64) == 0) {
267 this = lcode[this.val + (hold & ((1U << op) - 1))];
268 goto dolen;
269 }
270 else if (op & 32) {
271 state->mode = TYPE;
272 break;
273 }
274 else {
275 strm->msg = (char *)"invalid literal/length code";
276 state->mode = BAD;
277 break;
278 }
279 } while (in < last && out < end);
280
281
282 len = bits >> 3;
283 in -= len;
284 bits -= len << 3;
285 hold &= (1U << bits) - 1;
286
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288 strm->next_in = in + OFF;
289 strm->next_out = out + OFF;
290 strm->avail_in = (unsigned)(in < last ? 5 + (last - in) : 5 - (in - last));
291 strm->avail_out = (unsigned)(out < end ?
292 257 + (end - out) : 257 - (out - end));
293 state->hold = hold;
294 state->bits = bits;
295 return;
296}
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312#endif
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