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authorRobert Griebl <griebl@gmx.de>2002-05-19 19:00:14 +0000
committerRobert Griebl <griebl@gmx.de>2002-05-19 19:00:14 +0000
commit94a6a956f0ec733e1c80ff97645692d041292088 (patch)
tree8ea7c7a9112731a1888da57665d43da58c4e67a5
parentc6def44cfc0de0f5eb3cafb2909908097d6d9e4b (diff)
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Support old-style compress (.Z) files via libbb / unzip( ) calls
(configurable) - When enabled an applet "uncompress" is also made available (oddname to gunzip) [the cvs add for this file got lost somehow...]
Diffstat
-rw-r--r--archival/libunarchive/decompress_uncompress.c313
-rw-r--r--archival/libunarchive/uncompress.c313
-rw-r--r--libbb/uncompress.c313
3 files changed, 939 insertions, 0 deletions
diff --git a/archival/libunarchive/decompress_uncompress.c b/archival/libunarchive/decompress_uncompress.c
new file mode 100644
index 000000000..903e6aa6d
--- /dev/null
+++ b/archival/libunarchive/decompress_uncompress.c
@@ -0,0 +1,313 @@
1#include "config.h"
2#include "libbb.h"
3
4#ifdef CONFIG_FEATURE_UNCOMPRESS
5
6/* uncompress for busybox -- (c) 2002 Robert Griebl
7 *
8 * based on the original compress42.c source
9 * (see disclaimer below)
10 */
11
12
13/* (N)compress42.c - File compression ala IEEE Computer, Mar 1992.
14 *
15 * Authors:
16 * Spencer W. Thomas (decvax!harpo!utah-cs!utah-gr!thomas)
17 * Jim McKie (decvax!mcvax!jim)
18 * Steve Davies (decvax!vax135!petsd!peora!srd)
19 * Ken Turkowski (decvax!decwrl!turtlevax!ken)
20 * James A. Woods (decvax!ihnp4!ames!jaw)
21 * Joe Orost (decvax!vax135!petsd!joe)
22 * Dave Mack (csu@alembic.acs.com)
23 * Peter Jannesen, Network Communication Systems
24 * (peter@ncs.nl)
25 *
26 * marc@suse.de : a small security fix for a buffer overflow
27 *
28 * [... History snipped ...]
29 *
30 */
31#include <stdio.h>
32
33
34#define IBUFSIZ 2048 /* Defailt input buffer size */
35#define OBUFSIZ 2048 /* Default output buffer size */
36
37 /* Defines for third byte of header */
38#define MAGIC_1 (char_type)'\037'/* First byte of compressed file */
39#define MAGIC_2 (char_type)'\235'/* Second byte of compressed file */
40#define BIT_MASK 0x1f /* Mask for 'number of compresssion bits' */
41 /* Masks 0x20 and 0x40 are free. */
42 /* I think 0x20 should mean that there is */
43 /* a fourth header byte (for expansion). */
44#define BLOCK_MODE 0x80 /* Block compresssion if table is full and */
45 /* compression rate is dropping flush tables */
46
47 /* the next two codes should not be changed lightly, as they must not */
48 /* lie within the contiguous general code space. */
49#define FIRST 257 /* first free entry */
50#define CLEAR 256 /* table clear output code */
51
52#define INIT_BITS 9 /* initial number of bits/code */
53
54
55/*
56 * machine variants which require cc -Dmachine: pdp11, z8000, DOS
57 */
58#define FAST
59
60#define HBITS 17 /* 50% occupancy */
61#define HSIZE (1<<HBITS)
62#define HMASK (HSIZE-1)
63#define HPRIME 9941
64#define BITS 16
65#undef MAXSEG_64K
66
67typedef long int code_int;
68
69typedef long int count_int;
70typedef long int cmp_code_int;
71
72typedef unsigned char char_type;
73
74#define MAXCODE(n) (1L << (n))
75
76
77
78int block_mode = BLOCK_MODE;/* Block compress mode -C compatible with 2.0*/
79int maxbits = BITS; /* user settable max # bits/code */
80int exit_code = -1; /* Exitcode of compress (-1 no file compressed) */
81
82char_type inbuf[IBUFSIZ+64]; /* Input buffer */
83char_type outbuf[OBUFSIZ+2048];/* Output buffer */
84
85
86count_int htab[HSIZE];
87unsigned short codetab[HSIZE];
88
89#define htabof(i) htab[i]
90#define codetabof(i) codetab[i]
91#define tab_prefixof(i) codetabof(i)
92#define tab_suffixof(i) ((char_type *)(htab))[i]
93#define de_stack ((char_type *)&(htab[HSIZE-1]))
94#define clear_htab() memset(htab, -1, sizeof(htab))
95#define clear_tab_prefixof() memset(codetab, 0, 256);
96
97
98extern int uncompress ( FILE *, FILE * );
99
100
101/*
102 * Decompress stdin to stdout. This routine adapts to the codes in the
103 * file building the "string" table on-the-fly; requiring no table to
104 * be stored in the compressed file. The tables used herein are shared
105 * with those of the compress() routine. See the definitions above.
106 */
107
108int uncompress ( FILE * fdin, FILE * fdout )
109{
110 char_type *stackp;
111 code_int code;
112 int finchar;
113 code_int oldcode;
114 code_int incode;
115 int inbits;
116 int posbits;
117 int outpos;
118 int insize;
119 int bitmask;
120 code_int free_ent;
121 code_int maxcode;
122 code_int maxmaxcode;
123 int n_bits;
124 int rsize = 0;
125
126 insize = 0;
127
128 inbuf [0] = fgetc(fdin);
129
130 maxbits = inbuf[0] & BIT_MASK;
131 block_mode = inbuf[0] & BLOCK_MODE;
132 maxmaxcode = MAXCODE(maxbits);
133
134 if (maxbits > BITS)
135 {
136 fprintf(stderr, "compressed with %d bits, can only handle %d bits\n", maxbits, BITS);
137 return -1;
138 }
139
140 //fprintf(stderr, "Bits: %d, block_mode: %d\n", maxbits, block_mode );
141
142 maxcode = MAXCODE(n_bits = INIT_BITS)-1;
143 bitmask = (1<<n_bits)-1;
144 oldcode = -1;
145 finchar = 0;
146 outpos = 0;
147 posbits = 0<<3;
148
149 free_ent = ((block_mode) ? FIRST : 256);
150
151 clear_tab_prefixof(); /* As above, initialize the first
152 256 entries in the table. */
153
154 for (code = 255 ; code >= 0 ; --code)
155 tab_suffixof(code) = (char_type)code;
156
157 do
158 {
159resetbuf: ;
160 {
161 int i;
162 int e;
163 int o;
164
165 e = insize-(o = (posbits>>3));
166
167 for (i = 0 ; i < e ; ++i)
168 inbuf[i] = inbuf[i+o];
169
170 insize = e;
171 posbits = 0;
172 }
173
174 if (insize < (int) sizeof(inbuf)-IBUFSIZ)
175 {
176 rsize = fread(inbuf+insize, 1,IBUFSIZ,fdin);
177
178 if ( !rsize && ferror(fdin))
179 return -1;
180
181 insize += rsize;
182 }
183
184 inbits = ((rsize > 0) ? (insize - insize%n_bits)<<3 :
185 (insize<<3)-(n_bits-1));
186
187 while (inbits > posbits)
188 {
189 if (free_ent > maxcode)
190 {
191 posbits = ((posbits-1) + ((n_bits<<3) -
192 (posbits-1+(n_bits<<3))%(n_bits<<3)));
193
194 ++n_bits;
195 if (n_bits == maxbits)
196 maxcode = maxmaxcode;
197 else
198 maxcode = MAXCODE(n_bits)-1;
199
200 bitmask = (1<<n_bits)-1;
201 goto resetbuf;
202 }
203
204
205 {
206 char_type *p = &inbuf[posbits>>3];
207 code = ((((long)(p[0]))|((long)(p[1])<<8)|((long)(p[2])<<16))>>(posbits&0x7))&bitmask;
208 }
209 posbits += n_bits;
210
211
212 if (oldcode == -1)
213 {
214 outbuf[outpos++] = (char_type)(finchar = (int)(oldcode = code));
215 continue;
216 }
217
218 if (code == CLEAR && block_mode)
219 {
220 clear_tab_prefixof();
221 free_ent = FIRST - 1;
222 posbits = ((posbits-1) + ((n_bits<<3) -
223 (posbits-1+(n_bits<<3))%(n_bits<<3)));
224 maxcode = MAXCODE(n_bits = INIT_BITS)-1;
225 bitmask = (1<<n_bits)-1;
226 goto resetbuf;
227 }
228
229 incode = code;
230 stackp = de_stack;
231
232 if (code >= free_ent) /* Special case for KwKwK string. */
233 {
234 if (code > free_ent)
235 {
236 char_type *p;
237
238 posbits -= n_bits;
239 p = &inbuf[posbits>>3];
240
241 fprintf(stderr, "insize:%d posbits:%d inbuf:%02X %02X %02X %02X %02X (%d)\n", insize, posbits,
242 p[-1],p[0],p[1],p[2],p[3], (posbits&07));
243 fprintf(stderr, "uncompress: corrupt input\n");
244 return -1;
245 }
246
247 *--stackp = (char_type)finchar;
248 code = oldcode;
249 }
250
251 while ((cmp_code_int)code >= (cmp_code_int)256)
252 { /* Generate output characters in reverse order */
253 *--stackp = tab_suffixof(code);
254 code = tab_prefixof(code);
255 }
256
257 *--stackp = (char_type)(finchar = tab_suffixof(code));
258
259 /* And put them out in forward order */
260
261 {
262 int i;
263
264 if (outpos+(i = (de_stack-stackp)) >= OBUFSIZ)
265 {
266 do
267 {
268 if (i > OBUFSIZ-outpos) i = OBUFSIZ-outpos;
269
270 if (i > 0)
271 {
272 memcpy(outbuf+outpos, stackp, i);
273 outpos += i;
274 }
275
276 if (outpos >= OBUFSIZ)
277 {
278 fwrite(outbuf, 1,outpos,fdout);
279
280 outpos = 0;
281 }
282 stackp+= i;
283 }
284 while ((i = (de_stack-stackp)) > 0);
285 }
286 else
287 {
288 memcpy(outbuf+outpos, stackp, i);
289 outpos += i;
290 }
291 }
292
293 if ((code = free_ent) < maxmaxcode) /* Generate the new entry. */
294 {
295 tab_prefixof(code) = (unsigned short)oldcode;
296 tab_suffixof(code) = (char_type)finchar;
297 free_ent = code+1;
298 }
299
300 oldcode = incode; /* Remember previous code. */
301 }
302
303 }
304 while (rsize > 0);
305
306 if (outpos > 0)
307 fwrite(outbuf, outpos,1, fdout);
308
309 return 0;
310}
311
312
313#endif
diff --git a/archival/libunarchive/uncompress.c b/archival/libunarchive/uncompress.c
new file mode 100644
index 000000000..903e6aa6d
--- /dev/null
+++ b/archival/libunarchive/uncompress.c
@@ -0,0 +1,313 @@
1#include "config.h"
2#include "libbb.h"
3
4#ifdef CONFIG_FEATURE_UNCOMPRESS
5
6/* uncompress for busybox -- (c) 2002 Robert Griebl
7 *
8 * based on the original compress42.c source
9 * (see disclaimer below)
10 */
11
12
13/* (N)compress42.c - File compression ala IEEE Computer, Mar 1992.
14 *
15 * Authors:
16 * Spencer W. Thomas (decvax!harpo!utah-cs!utah-gr!thomas)
17 * Jim McKie (decvax!mcvax!jim)
18 * Steve Davies (decvax!vax135!petsd!peora!srd)
19 * Ken Turkowski (decvax!decwrl!turtlevax!ken)
20 * James A. Woods (decvax!ihnp4!ames!jaw)
21 * Joe Orost (decvax!vax135!petsd!joe)
22 * Dave Mack (csu@alembic.acs.com)
23 * Peter Jannesen, Network Communication Systems
24 * (peter@ncs.nl)
25 *
26 * marc@suse.de : a small security fix for a buffer overflow
27 *
28 * [... History snipped ...]
29 *
30 */
31#include <stdio.h>
32
33
34#define IBUFSIZ 2048 /* Defailt input buffer size */
35#define OBUFSIZ 2048 /* Default output buffer size */
36
37 /* Defines for third byte of header */
38#define MAGIC_1 (char_type)'\037'/* First byte of compressed file */
39#define MAGIC_2 (char_type)'\235'/* Second byte of compressed file */
40#define BIT_MASK 0x1f /* Mask for 'number of compresssion bits' */
41 /* Masks 0x20 and 0x40 are free. */
42 /* I think 0x20 should mean that there is */
43 /* a fourth header byte (for expansion). */
44#define BLOCK_MODE 0x80 /* Block compresssion if table is full and */
45 /* compression rate is dropping flush tables */
46
47 /* the next two codes should not be changed lightly, as they must not */
48 /* lie within the contiguous general code space. */
49#define FIRST 257 /* first free entry */
50#define CLEAR 256 /* table clear output code */
51
52#define INIT_BITS 9 /* initial number of bits/code */
53
54
55/*
56 * machine variants which require cc -Dmachine: pdp11, z8000, DOS
57 */
58#define FAST
59
60#define HBITS 17 /* 50% occupancy */
61#define HSIZE (1<<HBITS)
62#define HMASK (HSIZE-1)
63#define HPRIME 9941
64#define BITS 16
65#undef MAXSEG_64K
66
67typedef long int code_int;
68
69typedef long int count_int;
70typedef long int cmp_code_int;
71
72typedef unsigned char char_type;
73
74#define MAXCODE(n) (1L << (n))
75
76
77
78int block_mode = BLOCK_MODE;/* Block compress mode -C compatible with 2.0*/
79int maxbits = BITS; /* user settable max # bits/code */
80int exit_code = -1; /* Exitcode of compress (-1 no file compressed) */
81
82char_type inbuf[IBUFSIZ+64]; /* Input buffer */
83char_type outbuf[OBUFSIZ+2048];/* Output buffer */
84
85
86count_int htab[HSIZE];
87unsigned short codetab[HSIZE];
88
89#define htabof(i) htab[i]
90#define codetabof(i) codetab[i]
91#define tab_prefixof(i) codetabof(i)
92#define tab_suffixof(i) ((char_type *)(htab))[i]
93#define de_stack ((char_type *)&(htab[HSIZE-1]))
94#define clear_htab() memset(htab, -1, sizeof(htab))
95#define clear_tab_prefixof() memset(codetab, 0, 256);
96
97
98extern int uncompress ( FILE *, FILE * );
99
100
101/*
102 * Decompress stdin to stdout. This routine adapts to the codes in the
103 * file building the "string" table on-the-fly; requiring no table to
104 * be stored in the compressed file. The tables used herein are shared
105 * with those of the compress() routine. See the definitions above.
106 */
107
108int uncompress ( FILE * fdin, FILE * fdout )
109{
110 char_type *stackp;
111 code_int code;
112 int finchar;
113 code_int oldcode;
114 code_int incode;
115 int inbits;
116 int posbits;
117 int outpos;
118 int insize;
119 int bitmask;
120 code_int free_ent;
121 code_int maxcode;
122 code_int maxmaxcode;
123 int n_bits;
124 int rsize = 0;
125
126 insize = 0;
127
128 inbuf [0] = fgetc(fdin);
129
130 maxbits = inbuf[0] & BIT_MASK;
131 block_mode = inbuf[0] & BLOCK_MODE;
132 maxmaxcode = MAXCODE(maxbits);
133
134 if (maxbits > BITS)
135 {
136 fprintf(stderr, "compressed with %d bits, can only handle %d bits\n", maxbits, BITS);
137 return -1;
138 }
139
140 //fprintf(stderr, "Bits: %d, block_mode: %d\n", maxbits, block_mode );
141
142 maxcode = MAXCODE(n_bits = INIT_BITS)-1;
143 bitmask = (1<<n_bits)-1;
144 oldcode = -1;
145 finchar = 0;
146 outpos = 0;
147 posbits = 0<<3;
148
149 free_ent = ((block_mode) ? FIRST : 256);
150
151 clear_tab_prefixof(); /* As above, initialize the first
152 256 entries in the table. */
153
154 for (code = 255 ; code >= 0 ; --code)
155 tab_suffixof(code) = (char_type)code;
156
157 do
158 {
159resetbuf: ;
160 {
161 int i;
162 int e;
163 int o;
164
165 e = insize-(o = (posbits>>3));
166
167 for (i = 0 ; i < e ; ++i)
168 inbuf[i] = inbuf[i+o];
169
170 insize = e;
171 posbits = 0;
172 }
173
174 if (insize < (int) sizeof(inbuf)-IBUFSIZ)
175 {
176 rsize = fread(inbuf+insize, 1,IBUFSIZ,fdin);
177
178 if ( !rsize && ferror(fdin))
179 return -1;
180
181 insize += rsize;
182 }
183
184 inbits = ((rsize > 0) ? (insize - insize%n_bits)<<3 :
185 (insize<<3)-(n_bits-1));
186
187 while (inbits > posbits)
188 {
189 if (free_ent > maxcode)
190 {
191 posbits = ((posbits-1) + ((n_bits<<3) -
192 (posbits-1+(n_bits<<3))%(n_bits<<3)));
193
194 ++n_bits;
195 if (n_bits == maxbits)
196 maxcode = maxmaxcode;
197 else
198 maxcode = MAXCODE(n_bits)-1;
199
200 bitmask = (1<<n_bits)-1;
201 goto resetbuf;
202 }
203
204
205 {
206 char_type *p = &inbuf[posbits>>3];
207 code = ((((long)(p[0]))|((long)(p[1])<<8)|((long)(p[2])<<16))>>(posbits&0x7))&bitmask;
208 }
209 posbits += n_bits;
210
211
212 if (oldcode == -1)
213 {
214 outbuf[outpos++] = (char_type)(finchar = (int)(oldcode = code));
215 continue;
216 }
217
218 if (code == CLEAR && block_mode)
219 {
220 clear_tab_prefixof();
221 free_ent = FIRST - 1;
222 posbits = ((posbits-1) + ((n_bits<<3) -
223 (posbits-1+(n_bits<<3))%(n_bits<<3)));
224 maxcode = MAXCODE(n_bits = INIT_BITS)-1;
225 bitmask = (1<<n_bits)-1;
226 goto resetbuf;
227 }
228
229 incode = code;
230 stackp = de_stack;
231
232 if (code >= free_ent) /* Special case for KwKwK string. */
233 {
234 if (code > free_ent)
235 {
236 char_type *p;
237
238 posbits -= n_bits;
239 p = &inbuf[posbits>>3];
240
241 fprintf(stderr, "insize:%d posbits:%d inbuf:%02X %02X %02X %02X %02X (%d)\n", insize, posbits,
242 p[-1],p[0],p[1],p[2],p[3], (posbits&07));
243 fprintf(stderr, "uncompress: corrupt input\n");
244 return -1;
245 }
246
247 *--stackp = (char_type)finchar;
248 code = oldcode;
249 }
250
251 while ((cmp_code_int)code >= (cmp_code_int)256)
252 { /* Generate output characters in reverse order */
253 *--stackp = tab_suffixof(code);
254 code = tab_prefixof(code);
255 }
256
257 *--stackp = (char_type)(finchar = tab_suffixof(code));
258
259 /* And put them out in forward order */
260
261 {
262 int i;
263
264 if (outpos+(i = (de_stack-stackp)) >= OBUFSIZ)
265 {
266 do
267 {
268 if (i > OBUFSIZ-outpos) i = OBUFSIZ-outpos;
269
270 if (i > 0)
271 {
272 memcpy(outbuf+outpos, stackp, i);
273 outpos += i;
274 }
275
276 if (outpos >= OBUFSIZ)
277 {
278 fwrite(outbuf, 1,outpos,fdout);
279
280 outpos = 0;
281 }
282 stackp+= i;
283 }
284 while ((i = (de_stack-stackp)) > 0);
285 }
286 else
287 {
288 memcpy(outbuf+outpos, stackp, i);
289 outpos += i;
290 }
291 }
292
293 if ((code = free_ent) < maxmaxcode) /* Generate the new entry. */
294 {
295 tab_prefixof(code) = (unsigned short)oldcode;
296 tab_suffixof(code) = (char_type)finchar;
297 free_ent = code+1;
298 }
299
300 oldcode = incode; /* Remember previous code. */
301 }
302
303 }
304 while (rsize > 0);
305
306 if (outpos > 0)
307 fwrite(outbuf, outpos,1, fdout);
308
309 return 0;
310}
311
312
313#endif
diff --git a/libbb/uncompress.c b/libbb/uncompress.c
new file mode 100644
index 000000000..903e6aa6d
--- /dev/null
+++ b/libbb/uncompress.c
@@ -0,0 +1,313 @@
1#include "config.h"
2#include "libbb.h"
3
4#ifdef CONFIG_FEATURE_UNCOMPRESS
5
6/* uncompress for busybox -- (c) 2002 Robert Griebl
7 *
8 * based on the original compress42.c source
9 * (see disclaimer below)
10 */
11
12
13/* (N)compress42.c - File compression ala IEEE Computer, Mar 1992.
14 *
15 * Authors:
16 * Spencer W. Thomas (decvax!harpo!utah-cs!utah-gr!thomas)
17 * Jim McKie (decvax!mcvax!jim)
18 * Steve Davies (decvax!vax135!petsd!peora!srd)
19 * Ken Turkowski (decvax!decwrl!turtlevax!ken)
20 * James A. Woods (decvax!ihnp4!ames!jaw)
21 * Joe Orost (decvax!vax135!petsd!joe)
22 * Dave Mack (csu@alembic.acs.com)
23 * Peter Jannesen, Network Communication Systems
24 * (peter@ncs.nl)
25 *
26 * marc@suse.de : a small security fix for a buffer overflow
27 *
28 * [... History snipped ...]
29 *
30 */
31#include <stdio.h>
32
33
34#define IBUFSIZ 2048 /* Defailt input buffer size */
35#define OBUFSIZ 2048 /* Default output buffer size */
36
37 /* Defines for third byte of header */
38#define MAGIC_1 (char_type)'\037'/* First byte of compressed file */
39#define MAGIC_2 (char_type)'\235'/* Second byte of compressed file */
40#define BIT_MASK 0x1f /* Mask for 'number of compresssion bits' */
41 /* Masks 0x20 and 0x40 are free. */
42 /* I think 0x20 should mean that there is */
43 /* a fourth header byte (for expansion). */
44#define BLOCK_MODE 0x80 /* Block compresssion if table is full and */
45 /* compression rate is dropping flush tables */
46
47 /* the next two codes should not be changed lightly, as they must not */
48 /* lie within the contiguous general code space. */
49#define FIRST 257 /* first free entry */
50#define CLEAR 256 /* table clear output code */
51
52#define INIT_BITS 9 /* initial number of bits/code */
53
54
55/*
56 * machine variants which require cc -Dmachine: pdp11, z8000, DOS
57 */
58#define FAST
59
60#define HBITS 17 /* 50% occupancy */
61#define HSIZE (1<<HBITS)
62#define HMASK (HSIZE-1)
63#define HPRIME 9941
64#define BITS 16
65#undef MAXSEG_64K
66
67typedef long int code_int;
68
69typedef long int count_int;
70typedef long int cmp_code_int;
71
72typedef unsigned char char_type;
73
74#define MAXCODE(n) (1L << (n))
75
76
77
78int block_mode = BLOCK_MODE;/* Block compress mode -C compatible with 2.0*/
79int maxbits = BITS; /* user settable max # bits/code */
80int exit_code = -1; /* Exitcode of compress (-1 no file compressed) */
81
82char_type inbuf[IBUFSIZ+64]; /* Input buffer */
83char_type outbuf[OBUFSIZ+2048];/* Output buffer */
84
85
86count_int htab[HSIZE];
87unsigned short codetab[HSIZE];
88
89#define htabof(i) htab[i]
90#define codetabof(i) codetab[i]
91#define tab_prefixof(i) codetabof(i)
92#define tab_suffixof(i) ((char_type *)(htab))[i]
93#define de_stack ((char_type *)&(htab[HSIZE-1]))
94#define clear_htab() memset(htab, -1, sizeof(htab))
95#define clear_tab_prefixof() memset(codetab, 0, 256);
96
97
98extern int uncompress ( FILE *, FILE * );
99
100
101/*
102 * Decompress stdin to stdout. This routine adapts to the codes in the
103 * file building the "string" table on-the-fly; requiring no table to
104 * be stored in the compressed file. The tables used herein are shared
105 * with those of the compress() routine. See the definitions above.
106 */
107
108int uncompress ( FILE * fdin, FILE * fdout )
109{
110 char_type *stackp;
111 code_int code;
112 int finchar;
113 code_int oldcode;
114 code_int incode;
115 int inbits;
116 int posbits;
117 int outpos;
118 int insize;
119 int bitmask;
120 code_int free_ent;
121 code_int maxcode;
122 code_int maxmaxcode;
123 int n_bits;
124 int rsize = 0;
125
126 insize = 0;
127
128 inbuf [0] = fgetc(fdin);
129
130 maxbits = inbuf[0] & BIT_MASK;
131 block_mode = inbuf[0] & BLOCK_MODE;
132 maxmaxcode = MAXCODE(maxbits);
133
134 if (maxbits > BITS)
135 {
136 fprintf(stderr, "compressed with %d bits, can only handle %d bits\n", maxbits, BITS);
137 return -1;
138 }
139
140 //fprintf(stderr, "Bits: %d, block_mode: %d\n", maxbits, block_mode );
141
142 maxcode = MAXCODE(n_bits = INIT_BITS)-1;
143 bitmask = (1<<n_bits)-1;
144 oldcode = -1;
145 finchar = 0;
146 outpos = 0;
147 posbits = 0<<3;
148
149 free_ent = ((block_mode) ? FIRST : 256);
150
151 clear_tab_prefixof(); /* As above, initialize the first
152 256 entries in the table. */
153
154 for (code = 255 ; code >= 0 ; --code)
155 tab_suffixof(code) = (char_type)code;
156
157 do
158 {
159resetbuf: ;
160 {
161 int i;
162 int e;
163 int o;
164
165 e = insize-(o = (posbits>>3));
166
167 for (i = 0 ; i < e ; ++i)
168 inbuf[i] = inbuf[i+o];
169
170 insize = e;
171 posbits = 0;
172 }
173
174 if (insize < (int) sizeof(inbuf)-IBUFSIZ)
175 {
176 rsize = fread(inbuf+insize, 1,IBUFSIZ,fdin);
177
178 if ( !rsize && ferror(fdin))
179 return -1;
180
181 insize += rsize;
182 }
183
184 inbits = ((rsize > 0) ? (insize - insize%n_bits)<<3 :
185 (insize<<3)-(n_bits-1));
186
187 while (inbits > posbits)
188 {
189 if (free_ent > maxcode)
190 {
191 posbits = ((posbits-1) + ((n_bits<<3) -
192 (posbits-1+(n_bits<<3))%(n_bits<<3)));
193
194 ++n_bits;
195 if (n_bits == maxbits)
196 maxcode = maxmaxcode;
197 else
198 maxcode = MAXCODE(n_bits)-1;
199
200 bitmask = (1<<n_bits)-1;
201 goto resetbuf;
202 }
203
204
205 {
206 char_type *p = &inbuf[posbits>>3];
207 code = ((((long)(p[0]))|((long)(p[1])<<8)|((long)(p[2])<<16))>>(posbits&0x7))&bitmask;
208 }
209 posbits += n_bits;
210
211
212 if (oldcode == -1)
213 {
214 outbuf[outpos++] = (char_type)(finchar = (int)(oldcode = code));
215 continue;
216 }
217
218 if (code == CLEAR && block_mode)
219 {
220 clear_tab_prefixof();
221 free_ent = FIRST - 1;
222 posbits = ((posbits-1) + ((n_bits<<3) -
223 (posbits-1+(n_bits<<3))%(n_bits<<3)));
224 maxcode = MAXCODE(n_bits = INIT_BITS)-1;
225 bitmask = (1<<n_bits)-1;
226 goto resetbuf;
227 }
228
229 incode = code;
230 stackp = de_stack;
231
232 if (code >= free_ent) /* Special case for KwKwK string. */
233 {
234 if (code > free_ent)
235 {
236 char_type *p;
237
238 posbits -= n_bits;
239 p = &inbuf[posbits>>3];
240
241 fprintf(stderr, "insize:%d posbits:%d inbuf:%02X %02X %02X %02X %02X (%d)\n", insize, posbits,
242 p[-1],p[0],p[1],p[2],p[3], (posbits&07));
243 fprintf(stderr, "uncompress: corrupt input\n");
244 return -1;
245 }
246
247 *--stackp = (char_type)finchar;
248 code = oldcode;
249 }
250
251 while ((cmp_code_int)code >= (cmp_code_int)256)
252 { /* Generate output characters in reverse order */
253 *--stackp = tab_suffixof(code);
254 code = tab_prefixof(code);
255 }
256
257 *--stackp = (char_type)(finchar = tab_suffixof(code));
258
259 /* And put them out in forward order */
260
261 {
262 int i;
263
264 if (outpos+(i = (de_stack-stackp)) >= OBUFSIZ)
265 {
266 do
267 {
268 if (i > OBUFSIZ-outpos) i = OBUFSIZ-outpos;
269
270 if (i > 0)
271 {
272 memcpy(outbuf+outpos, stackp, i);
273 outpos += i;
274 }
275
276 if (outpos >= OBUFSIZ)
277 {
278 fwrite(outbuf, 1,outpos,fdout);
279
280 outpos = 0;
281 }
282 stackp+= i;
283 }
284 while ((i = (de_stack-stackp)) > 0);
285 }
286 else
287 {
288 memcpy(outbuf+outpos, stackp, i);
289 outpos += i;
290 }
291 }
292
293 if ((code = free_ent) < maxmaxcode) /* Generate the new entry. */
294 {
295 tab_prefixof(code) = (unsigned short)oldcode;
296 tab_suffixof(code) = (char_type)finchar;
297 free_ent = code+1;
298 }
299
300 oldcode = incode; /* Remember previous code. */
301 }
302
303 }
304 while (rsize > 0);
305
306 if (outpos > 0)
307 fwrite(outbuf, outpos,1, fdout);
308
309 return 0;
310}
311
312
313#endif
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