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authorRob Landley <rob@landley.net>2006-01-20 18:28:50 +0000
committerRob Landley <rob@landley.net>2006-01-20 18:28:50 +0000
commitc1d69906a0c5f28f3d84c14afb3b74c8f19f81c1 (patch)
tree5e3796c33b995720bcd69f2b969e409e85bff119 /archival/libunarchive
parent7a43bd07e64e6db795d4661321da1cab14d9c4f6 (diff)
downloadbusybox-w32-c1d69906a0c5f28f3d84c14afb3b74c8f19f81c1.tar.gz
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busybox-w32-c1d69906a0c5f28f3d84c14afb3b74c8f19f81c1.zip
Patch from Aurelien Jacobs to add unlzma. (A new decompression type,
see www.7-zip.org)
Diffstat (limited to 'archival/libunarchive')
-rw-r--r--archival/libunarchive/Makefile.in3
-rw-r--r--archival/libunarchive/decompress_unlzma.c347
-rw-r--r--archival/libunarchive/filter_accept_list_reassign.c4
-rw-r--r--archival/libunarchive/get_header_tar_lzma.c23
-rw-r--r--archival/libunarchive/rangecoder.h158
5 files changed, 535 insertions, 0 deletions
diff --git a/archival/libunarchive/Makefile.in b/archival/libunarchive/Makefile.in
index 99eb6386d..2b49398df 100644
--- a/archival/libunarchive/Makefile.in
+++ b/archival/libunarchive/Makefile.in
@@ -51,17 +51,20 @@ DPKG_FILES:= \
51 51
52LIBUNARCHIVE-$(CONFIG_AR) += get_header_ar.o unpack_ar_archive.o 52LIBUNARCHIVE-$(CONFIG_AR) += get_header_ar.o unpack_ar_archive.o
53LIBUNARCHIVE-$(CONFIG_BUNZIP2) += decompress_bunzip2.o 53LIBUNARCHIVE-$(CONFIG_BUNZIP2) += decompress_bunzip2.o
54LIBUNARCHIVE-$(CONFIG_UNLZMA) += decompress_unlzma.o
54LIBUNARCHIVE-$(CONFIG_CPIO) += get_header_cpio.o 55LIBUNARCHIVE-$(CONFIG_CPIO) += get_header_cpio.o
55LIBUNARCHIVE-$(CONFIG_DPKG) += $(DPKG_FILES) 56LIBUNARCHIVE-$(CONFIG_DPKG) += $(DPKG_FILES)
56LIBUNARCHIVE-$(CONFIG_DPKG_DEB) += $(DPKG_FILES) 57LIBUNARCHIVE-$(CONFIG_DPKG_DEB) += $(DPKG_FILES)
57LIBUNARCHIVE-$(CONFIG_FEATURE_DEB_TAR_GZ) += $(GUNZIP_FILES) get_header_tar_gz.o 58LIBUNARCHIVE-$(CONFIG_FEATURE_DEB_TAR_GZ) += $(GUNZIP_FILES) get_header_tar_gz.o
58LIBUNARCHIVE-$(CONFIG_FEATURE_DEB_TAR_BZ2) += decompress_bunzip2.o get_header_tar_bz2.o 59LIBUNARCHIVE-$(CONFIG_FEATURE_DEB_TAR_BZ2) += decompress_bunzip2.o get_header_tar_bz2.o
60LIBUNARCHIVE-$(CONFIG_FEATURE_DEB_TAR_LZMA) += decompress_unlzma.o get_header_tar_lzma.o
59LIBUNARCHIVE-$(CONFIG_GUNZIP) += $(GUNZIP_FILES) 61LIBUNARCHIVE-$(CONFIG_GUNZIP) += $(GUNZIP_FILES)
60LIBUNARCHIVE-$(CONFIG_FEATURE_GUNZIP_UNCOMPRESS) += decompress_uncompress.o 62LIBUNARCHIVE-$(CONFIG_FEATURE_GUNZIP_UNCOMPRESS) += decompress_uncompress.o
61LIBUNARCHIVE-$(CONFIG_RPM2CPIO) += $(GUNZIP_FILES) get_header_cpio.o 63LIBUNARCHIVE-$(CONFIG_RPM2CPIO) += $(GUNZIP_FILES) get_header_cpio.o
62LIBUNARCHIVE-$(CONFIG_RPM) += $(GUNZIP_FILES) get_header_cpio.o 64LIBUNARCHIVE-$(CONFIG_RPM) += $(GUNZIP_FILES) get_header_cpio.o
63LIBUNARCHIVE-$(CONFIG_TAR) += get_header_tar.o 65LIBUNARCHIVE-$(CONFIG_TAR) += get_header_tar.o
64LIBUNARCHIVE-$(CONFIG_FEATURE_TAR_BZIP2) += decompress_bunzip2.o get_header_tar_bz2.o 66LIBUNARCHIVE-$(CONFIG_FEATURE_TAR_BZIP2) += decompress_bunzip2.o get_header_tar_bz2.o
67LIBUNARCHIVE-$(CONFIG_FEATURE_TAR_LZMA) += decompress_unlzma.o get_header_tar_lzma.o
65LIBUNARCHIVE-$(CONFIG_FEATURE_TAR_GZIP) += $(GUNZIP_FILES) get_header_tar_gz.o 68LIBUNARCHIVE-$(CONFIG_FEATURE_TAR_GZIP) += $(GUNZIP_FILES) get_header_tar_gz.o
66LIBUNARCHIVE-$(CONFIG_FEATURE_TAR_COMPRESS) += decompress_uncompress.o 69LIBUNARCHIVE-$(CONFIG_FEATURE_TAR_COMPRESS) += decompress_uncompress.o
67LIBUNARCHIVE-$(CONFIG_UNCOMPRESS) += decompress_uncompress.o 70LIBUNARCHIVE-$(CONFIG_UNCOMPRESS) += decompress_uncompress.o
diff --git a/archival/libunarchive/decompress_unlzma.c b/archival/libunarchive/decompress_unlzma.c
new file mode 100644
index 000000000..977cb48d0
--- /dev/null
+++ b/archival/libunarchive/decompress_unlzma.c
@@ -0,0 +1,347 @@
1/*
2 * Small lzma deflate implementation.
3 * Copyright (C) 2006 Aurelien Jacobs <aurel@gnuage.org>
4 *
5 * Based on LzmaDecode.c from the LZMA SDK 4.22 (http://www.7-zip.org/)
6 * Copyright (C) 1999-2005 Igor Pavlov
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with this library; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
21 */
22
23#include <stdint.h>
24#include <unistd.h>
25#include <stdio.h>
26#include <byteswap.h>
27
28#include "libbb.h"
29
30#include "rangecoder.h"
31
32
33typedef struct {
34 uint8_t pos;
35 uint32_t dict_size;
36 uint64_t dst_size;
37} __attribute__ ((packed)) lzma_header_t;
38
39
40#define LZMA_BASE_SIZE 1846
41#define LZMA_LIT_SIZE 768
42
43#define LZMA_NUM_POS_BITS_MAX 4
44
45#define LZMA_LEN_NUM_LOW_BITS 3
46#define LZMA_LEN_NUM_MID_BITS 3
47#define LZMA_LEN_NUM_HIGH_BITS 8
48
49#define LZMA_LEN_CHOICE 0
50#define LZMA_LEN_CHOICE_2 (LZMA_LEN_CHOICE + 1)
51#define LZMA_LEN_LOW (LZMA_LEN_CHOICE_2 + 1)
52#define LZMA_LEN_MID (LZMA_LEN_LOW \
53 + (1 << (LZMA_NUM_POS_BITS_MAX + LZMA_LEN_NUM_LOW_BITS)))
54#define LZMA_LEN_HIGH (LZMA_LEN_MID \
55 +(1 << (LZMA_NUM_POS_BITS_MAX + LZMA_LEN_NUM_MID_BITS)))
56#define LZMA_NUM_LEN_PROBS (LZMA_LEN_HIGH + (1 << LZMA_LEN_NUM_HIGH_BITS))
57
58#define LZMA_NUM_STATES 12
59#define LZMA_NUM_LIT_STATES 7
60
61#define LZMA_START_POS_MODEL_INDEX 4
62#define LZMA_END_POS_MODEL_INDEX 14
63#define LZMA_NUM_FULL_DISTANCES (1 << (LZMA_END_POS_MODEL_INDEX >> 1))
64
65#define LZMA_NUM_POS_SLOT_BITS 6
66#define LZMA_NUM_LEN_TO_POS_STATES 4
67
68#define LZMA_NUM_ALIGN_BITS 4
69
70#define LZMA_MATCH_MIN_LEN 2
71
72#define LZMA_IS_MATCH 0
73#define LZMA_IS_REP (LZMA_IS_MATCH + (LZMA_NUM_STATES <<LZMA_NUM_POS_BITS_MAX))
74#define LZMA_IS_REP_G0 (LZMA_IS_REP + LZMA_NUM_STATES)
75#define LZMA_IS_REP_G1 (LZMA_IS_REP_G0 + LZMA_NUM_STATES)
76#define LZMA_IS_REP_G2 (LZMA_IS_REP_G1 + LZMA_NUM_STATES)
77#define LZMA_IS_REP_0_LONG (LZMA_IS_REP_G2 + LZMA_NUM_STATES)
78#define LZMA_POS_SLOT (LZMA_IS_REP_0_LONG \
79 + (LZMA_NUM_STATES << LZMA_NUM_POS_BITS_MAX))
80#define LZMA_SPEC_POS (LZMA_POS_SLOT \
81 +(LZMA_NUM_LEN_TO_POS_STATES << LZMA_NUM_POS_SLOT_BITS))
82#define LZMA_ALIGN (LZMA_SPEC_POS \
83 + LZMA_NUM_FULL_DISTANCES - LZMA_END_POS_MODEL_INDEX)
84#define LZMA_LEN_CODER (LZMA_ALIGN + (1 << LZMA_NUM_ALIGN_BITS))
85#define LZMA_REP_LEN_CODER (LZMA_LEN_CODER + LZMA_NUM_LEN_PROBS)
86#define LZMA_LITERAL (LZMA_REP_LEN_CODER + LZMA_NUM_LEN_PROBS)
87
88
89int unlzma(int src_fd, int dst_fd)
90{
91 lzma_header_t header;
92 int lc, pb, lp;
93 uint32_t pos_state_mask;
94 uint32_t literal_pos_mask;
95 uint32_t pos;
96 uint16_t *p;
97 uint16_t *prob;
98 uint16_t *prob_lit;
99 int num_bits;
100 int num_probs;
101 rc_t rc;
102 int i, mi;
103 uint8_t *buffer;
104 uint8_t previous_byte = 0;
105 size_t buffer_pos = 0, global_pos = 0;
106 int len = 0;
107 int state = 0;
108 uint32_t rep0 = 1, rep1 = 1, rep2 = 1, rep3 = 1;
109
110 if (read(src_fd, &header, sizeof(header)) != sizeof(header))
111 bb_error_msg_and_die("can't read header");
112
113 if (header.pos >= (9 * 5 * 5))
114 bb_error_msg_and_die("bad header");
115 mi = header.pos / 9;
116 lc = header.pos % 9;
117 pb = mi / 5;
118 lp = mi % 5;
119 pos_state_mask = (1 << pb) - 1;
120 literal_pos_mask = (1 << lp) - 1;
121
122#if __BYTE_ORDER == __BIG_ENDIAN
123 header.dict_size = bswap_32(header.dict_size);
124 header.dst_size = bswap_64(header.dst_size);
125#endif /* __BYTE_ORDER */
126
127 if (header.dict_size == 0)
128 header.dict_size = 1;
129
130 buffer = xmalloc(MIN(header.dst_size, header.dict_size));
131
132 num_probs = LZMA_BASE_SIZE + (LZMA_LIT_SIZE << (lc + lp));
133 p = xmalloc(num_probs * sizeof(*p));
134 num_probs = LZMA_LITERAL + (LZMA_LIT_SIZE << (lc + lp));
135 for (i = 0; i < num_probs; i++)
136 p[i] = (1 << RC_MODEL_TOTAL_BITS) >> 1;
137
138 rc_init(&rc, src_fd, 0x10000);
139
140 while (global_pos + buffer_pos < header.dst_size) {
141 int pos_state = (buffer_pos + global_pos) & pos_state_mask;
142
143 prob =
144 p + LZMA_IS_MATCH + (state << LZMA_NUM_POS_BITS_MAX) + pos_state;
145 if (rc_is_bit_0(&rc, prob)) {
146 mi = 1;
147 rc_update_bit_0(&rc, prob);
148 prob = (p + LZMA_LITERAL + (LZMA_LIT_SIZE
149 * ((((buffer_pos + global_pos) & literal_pos_mask) << lc)
150 + (previous_byte >> (8 - lc)))));
151
152 if (state >= LZMA_NUM_LIT_STATES) {
153 int match_byte;
154
155 pos = buffer_pos - rep0;
156 while (pos >= header.dict_size)
157 pos += header.dict_size;
158 match_byte = buffer[pos];
159 do {
160 int bit;
161
162 match_byte <<= 1;
163 bit = match_byte & 0x100;
164 prob_lit = prob + 0x100 + bit + mi;
165 if (rc_get_bit(&rc, prob_lit, &mi)) {
166 if (!bit)
167 break;
168 } else {
169 if (bit)
170 break;
171 }
172 } while (mi < 0x100);
173 }
174 while (mi < 0x100) {
175 prob_lit = prob + mi;
176 rc_get_bit(&rc, prob_lit, &mi);
177 }
178 previous_byte = (uint8_t) mi;
179
180 buffer[buffer_pos++] = previous_byte;
181 if (buffer_pos == header.dict_size) {
182 buffer_pos = 0;
183 global_pos += header.dict_size;
184 write(dst_fd, buffer, header.dict_size);
185 }
186 if (state < 4)
187 state = 0;
188 else if (state < 10)
189 state -= 3;
190 else
191 state -= 6;
192 } else {
193 int offset;
194 uint16_t *prob_len;
195
196 rc_update_bit_1(&rc, prob);
197 prob = p + LZMA_IS_REP + state;
198 if (rc_is_bit_0(&rc, prob)) {
199 rc_update_bit_0(&rc, prob);
200 rep3 = rep2;
201 rep2 = rep1;
202 rep1 = rep0;
203 state = state < LZMA_NUM_LIT_STATES ? 0 : 3;
204 prob = p + LZMA_LEN_CODER;
205 } else {
206 rc_update_bit_1(&rc, prob);
207 prob = p + LZMA_IS_REP_G0 + state;
208 if (rc_is_bit_0(&rc, prob)) {
209 rc_update_bit_0(&rc, prob);
210 prob = (p + LZMA_IS_REP_0_LONG
211 + (state << LZMA_NUM_POS_BITS_MAX) + pos_state);
212 if (rc_is_bit_0(&rc, prob)) {
213 rc_update_bit_0(&rc, prob);
214
215 state = state < LZMA_NUM_LIT_STATES ? 9 : 11;
216 pos = buffer_pos - rep0;
217 while (pos >= header.dict_size)
218 pos += header.dict_size;
219 previous_byte = buffer[pos];
220 buffer[buffer_pos++] = previous_byte;
221 if (buffer_pos == header.dict_size) {
222 buffer_pos = 0;
223 global_pos += header.dict_size;
224 write(dst_fd, buffer, header.dict_size);
225 }
226 continue;
227 } else {
228 rc_update_bit_1(&rc, prob);
229 }
230 } else {
231 uint32_t distance;
232
233 rc_update_bit_1(&rc, prob);
234 prob = p + LZMA_IS_REP_G1 + state;
235 if (rc_is_bit_0(&rc, prob)) {
236 rc_update_bit_0(&rc, prob);
237 distance = rep1;
238 } else {
239 rc_update_bit_1(&rc, prob);
240 prob = p + LZMA_IS_REP_G2 + state;
241 if (rc_is_bit_0(&rc, prob)) {
242 rc_update_bit_0(&rc, prob);
243 distance = rep2;
244 } else {
245 rc_update_bit_1(&rc, prob);
246 distance = rep3;
247 rep3 = rep2;
248 }
249 rep2 = rep1;
250 }
251 rep1 = rep0;
252 rep0 = distance;
253 }
254 state = state < LZMA_NUM_LIT_STATES ? 8 : 11;
255 prob = p + LZMA_REP_LEN_CODER;
256 }
257
258 prob_len = prob + LZMA_LEN_CHOICE;
259 if (rc_is_bit_0(&rc, prob_len)) {
260 rc_update_bit_0(&rc, prob_len);
261 prob_len = (prob + LZMA_LEN_LOW
262 + (pos_state << LZMA_LEN_NUM_LOW_BITS));
263 offset = 0;
264 num_bits = LZMA_LEN_NUM_LOW_BITS;
265 } else {
266 rc_update_bit_1(&rc, prob_len);
267 prob_len = prob + LZMA_LEN_CHOICE_2;
268 if (rc_is_bit_0(&rc, prob_len)) {
269 rc_update_bit_0(&rc, prob_len);
270 prob_len = (prob + LZMA_LEN_MID
271 + (pos_state << LZMA_LEN_NUM_MID_BITS));
272 offset = 1 << LZMA_LEN_NUM_LOW_BITS;
273 num_bits = LZMA_LEN_NUM_MID_BITS;
274 } else {
275 rc_update_bit_1(&rc, prob_len);
276 prob_len = prob + LZMA_LEN_HIGH;
277 offset = ((1 << LZMA_LEN_NUM_LOW_BITS)
278 + (1 << LZMA_LEN_NUM_MID_BITS));
279 num_bits = LZMA_LEN_NUM_HIGH_BITS;
280 }
281 }
282 rc_bit_tree_decode(&rc, prob_len, num_bits, &len);
283 len += offset;
284
285 if (state < 4) {
286 int pos_slot;
287
288 state += LZMA_NUM_LIT_STATES;
289 prob =
290 p + LZMA_POS_SLOT +
291 ((len <
292 LZMA_NUM_LEN_TO_POS_STATES ? len :
293 LZMA_NUM_LEN_TO_POS_STATES - 1)
294 << LZMA_NUM_POS_SLOT_BITS);
295 rc_bit_tree_decode(&rc, prob, LZMA_NUM_POS_SLOT_BITS,
296 &pos_slot);
297 if (pos_slot >= LZMA_START_POS_MODEL_INDEX) {
298 num_bits = (pos_slot >> 1) - 1;
299 rep0 = 2 | (pos_slot & 1);
300 if (pos_slot < LZMA_END_POS_MODEL_INDEX) {
301 rep0 <<= num_bits;
302 prob = p + LZMA_SPEC_POS + rep0 - pos_slot - 1;
303 } else {
304 num_bits -= LZMA_NUM_ALIGN_BITS;
305 while (num_bits--)
306 rep0 = (rep0 << 1) | rc_direct_bit(&rc);
307 prob = p + LZMA_ALIGN;
308 rep0 <<= LZMA_NUM_ALIGN_BITS;
309 num_bits = LZMA_NUM_ALIGN_BITS;
310 }
311 i = 1;
312 mi = 1;
313 while (num_bits--) {
314 if (rc_get_bit(&rc, prob + mi, &mi))
315 rep0 |= i;
316 i <<= 1;
317 }
318 } else
319 rep0 = pos_slot;
320 if (++rep0 == 0)
321 break;
322 }
323
324 len += LZMA_MATCH_MIN_LEN;
325
326 do {
327 pos = buffer_pos - rep0;
328 while (pos >= header.dict_size)
329 pos += header.dict_size;
330 previous_byte = buffer[pos];
331 buffer[buffer_pos++] = previous_byte;
332 if (buffer_pos == header.dict_size) {
333 buffer_pos = 0;
334 global_pos += header.dict_size;
335 write(dst_fd, buffer, header.dict_size);
336 }
337 len--;
338 } while (len != 0 && buffer_pos < header.dst_size);
339 }
340 }
341
342 write(dst_fd, buffer, buffer_pos);
343 rc_free(&rc);
344 return 0;
345}
346
347/* vi:set ts=4: */
diff --git a/archival/libunarchive/filter_accept_list_reassign.c b/archival/libunarchive/filter_accept_list_reassign.c
index d0436549b..a09f564a3 100644
--- a/archival/libunarchive/filter_accept_list_reassign.c
+++ b/archival/libunarchive/filter_accept_list_reassign.c
@@ -50,6 +50,10 @@ extern char filter_accept_list_reassign(archive_handle_t *archive_handle)
50 return(EXIT_SUCCESS); 50 return(EXIT_SUCCESS);
51 } 51 }
52#endif 52#endif
53 if (ENABLE_FEATURE_DEB_TAR_LZMA && !strcmp(name_ptr, ".lzma")) {
54 archive_handle->action_data_subarchive = get_header_tar_lzma;
55 return(EXIT_SUCCESS);
56 }
53 } 57 }
54 return(EXIT_FAILURE); 58 return(EXIT_FAILURE);
55} 59}
diff --git a/archival/libunarchive/get_header_tar_lzma.c b/archival/libunarchive/get_header_tar_lzma.c
new file mode 100644
index 000000000..63dc8bc2c
--- /dev/null
+++ b/archival/libunarchive/get_header_tar_lzma.c
@@ -0,0 +1,23 @@
1/*
2 * Small lzma deflate implementation.
3 * Copyright (C) 2006 Aurelien Jacobs <aurel@gnuage.org>
4 *
5 * Licensed under GPL v2, see file LICENSE in this tarball for details.
6 */
7
8#include "unarchive.h"
9
10char get_header_tar_lzma(archive_handle_t * archive_handle)
11{
12 /* Can't lseek over pipes */
13 archive_handle->seek = seek_by_char;
14
15 archive_handle->src_fd = open_transformer(archive_handle->src_fd, unlzma);
16 archive_handle->offset = 0;
17 while (get_header_tar(archive_handle) == EXIT_SUCCESS);
18
19 /* Can only do one file at a time */
20 return EXIT_FAILURE;
21}
22
23/* vi:set ts=4: */
diff --git a/archival/libunarchive/rangecoder.h b/archival/libunarchive/rangecoder.h
new file mode 100644
index 000000000..bb4159112
--- /dev/null
+++ b/archival/libunarchive/rangecoder.h
@@ -0,0 +1,158 @@
1/*
2 * Small range coder implementation for lzma.
3 * Copyright (C) 2006 Aurelien Jacobs <aurel@gnuage.org>
4 *
5 * Based on LzmaDecode.c from the LZMA SDK 4.22 (http://www.7-zip.org/)
6 * Copyright (c) 1999-2005 Igor Pavlov
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with this library; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
21 */
22
23#include <stdint.h>
24
25#include "libbb.h"
26
27#ifndef always_inline
28# if defined(__GNUC__) && (__GNUC__ > 3 || __GNUC__ == 3 && __GNUC_MINOR__ >0)
29# define always_inline __attribute__((always_inline)) inline
30# else
31# define always_inline inline
32# endif
33#endif
34
35#ifdef CONFIG_FEATURE_LZMA_FAST
36# define speed_inline always_inline
37#else
38# define speed_inline
39#endif
40
41
42typedef struct {
43 int fd;
44 uint8_t *ptr;
45 uint8_t *buffer;
46 uint8_t *buffer_end;
47 int buffer_size;
48 uint32_t code;
49 uint32_t range;
50 uint32_t bound;
51} rc_t;
52
53
54#define RC_TOP_BITS 24
55#define RC_MOVE_BITS 5
56#define RC_MODEL_TOTAL_BITS 11
57
58
59static speed_inline void rc_read(rc_t * rc)
60{
61 rc->buffer_size = read(rc->fd, rc->buffer, rc->buffer_size);
62 if (rc->buffer_size <= 0)
63 bb_error_msg_and_die("unexpected EOF");
64 rc->ptr = rc->buffer;
65 rc->buffer_end = rc->buffer + rc->buffer_size;
66}
67
68static always_inline void rc_init(rc_t * rc, int fd, int buffer_size)
69{
70 int i;
71
72 rc->fd = fd;
73 rc->buffer = malloc(buffer_size);
74 rc->buffer_size = buffer_size;
75 rc->buffer_end = rc->buffer + rc->buffer_size;
76 rc->ptr = rc->buffer_end;
77
78 rc->code = 0;
79 rc->range = 0xFFFFFFFF;
80 for (i = 0; i < 5; i++) {
81 if (rc->ptr >= rc->buffer_end)
82 rc_read(rc);
83 rc->code = (rc->code << 8) | *rc->ptr++;
84 }
85}
86
87static always_inline void rc_free(rc_t * rc)
88{
89 if (ENABLE_FEATURE_CLEAN_UP)
90 free(rc->buffer);
91}
92
93static always_inline void rc_normalize(rc_t * rc)
94{
95 if (rc->range < (1 << RC_TOP_BITS)) {
96 if (rc->ptr >= rc->buffer_end)
97 rc_read(rc);
98 rc->range <<= 8;
99 rc->code = (rc->code << 8) | *rc->ptr++;
100 }
101}
102
103static speed_inline int rc_is_bit_0(rc_t * rc, uint16_t * p)
104{
105 rc_normalize(rc);
106 rc->bound = *p * (rc->range >> RC_MODEL_TOTAL_BITS);
107 return rc->code < rc->bound;
108}
109
110static speed_inline void rc_update_bit_0(rc_t * rc, uint16_t * p)
111{
112 rc->range = rc->bound;
113 *p += ((1 << RC_MODEL_TOTAL_BITS) - *p) >> RC_MOVE_BITS;
114}
115
116static speed_inline void rc_update_bit_1(rc_t * rc, uint16_t * p)
117{
118 rc->range -= rc->bound;
119 rc->code -= rc->bound;
120 *p -= *p >> RC_MOVE_BITS;
121}
122
123static speed_inline int rc_get_bit(rc_t * rc, uint16_t * p, int *symbol)
124{
125 if (rc_is_bit_0(rc, p)) {
126 rc_update_bit_0(rc, p);
127 *symbol *= 2;
128 return 0;
129 } else {
130 rc_update_bit_1(rc, p);
131 *symbol = *symbol * 2 + 1;
132 return 1;
133 }
134}
135
136static always_inline int rc_direct_bit(rc_t * rc)
137{
138 rc_normalize(rc);
139 rc->range >>= 1;
140 if (rc->code >= rc->range) {
141 rc->code -= rc->range;
142 return 1;
143 }
144 return 0;
145}
146
147static speed_inline void
148rc_bit_tree_decode(rc_t * rc, uint16_t * p, int num_levels, int *symbol)
149{
150 int i = num_levels;
151
152 *symbol = 1;
153 while (i--)
154 rc_get_bit(rc, p + *symbol, symbol);
155 *symbol -= 1 << num_levels;
156}
157
158/* vi:set ts=4: */
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