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use unified write_file function everywhere...
[rsbs2] / rsb-lz.c
1 #include <stdio.h>
2 #include <stdlib.h>
3 #include <strings.h>
4 #include <string.h>
5 #include <unistd.h>
6 #include <errno.h>
7 #include "rsb-crc.h"
8 #include "rsb-lz.h"
9 #include "filesystem.h"
10
11 void err_exit(const char *fname)
12 {
13 fprintf(stderr,"%s: error extracting...\n", fname);
14 exit(1);
15 }
16
17 struct data_in_s {
18 unsigned char *start;
19 unsigned char *stop;
20 unsigned char bitpos;
21 unsigned char byte;
22 };
23
24 struct data_out_s {
25 unsigned char *pos;
26 unsigned char *end;
27 };
28
29 unsigned char get_next_in_byte(struct data_in_s *data_in)
30 {
31 unsigned char byte;
32
33 if (data_in->stop < data_in->start)
34 err_exit(__func__);
35
36 byte = *(data_in->start);
37 data_in->start++;
38
39 return byte;
40 }
41
42 unsigned char get_next_bit(struct data_in_s *data_in)
43 {
44 unsigned char bitval;
45
46 if (data_in->bitpos == 0x80) {
47 data_in->byte = get_next_in_byte(data_in);
48 }
49
50 bitval = data_in->bitpos & data_in->byte;
51
52 data_in->bitpos >>= 1;
53 if (data_in->bitpos == 0) {
54 data_in->bitpos = 0x80;
55 }
56
57 if (bitval == 0)
58 return 0;
59
60 return 1;
61 }
62
63 unsigned int get_next_bits(struct data_in_s *data_in, unsigned int bits)
64 {
65 unsigned int bit;
66 unsigned int next_bits;
67
68 bit = 1 << (bits - 1);
69
70 next_bits = 0;
71 while (bit != 0) {
72 if (data_in->bitpos == 0x80) {
73 data_in->byte = get_next_in_byte(data_in);
74 }
75
76 if ((data_in->bitpos & data_in->byte) != 0)
77 next_bits = next_bits | bit;
78
79 bit = bit >> 1;
80
81 data_in->bitpos >>= 1;
82
83 if(data_in->bitpos == 0) {
84 data_in->bitpos = 0x80;
85 }
86 }
87
88 return next_bits;
89 }
90
91 void write_byte(unsigned char byte, struct data_out_s *data_out)
92 {
93 if (data_out->pos > data_out->end) {
94 err_exit(__func__);
95 }
96
97 *(data_out->pos) = byte;
98 data_out->pos++;
99 }
100
101 void lz_expand(struct data_in_s *data_in, struct data_out_s *data_out)
102 {
103 unsigned int pos;
104 unsigned int wordoffset;
105 unsigned int i;
106 unsigned char byte;
107 unsigned int wordlen;
108 unsigned char buf[1024];
109
110 pos = 1;
111
112 while (1) {
113 while (1) {
114 /* Compressed/uncompressed? */
115 if (get_next_bit(data_in) == 0)
116 break;
117
118 /* Uncompressed byte */
119 byte = get_next_bits(data_in, 8);
120
121 write_byte(byte, data_out);
122
123 /* Save byte in buffer, to be reused later */
124 buf[pos] = byte;
125 pos = (pos + 1) & 0x3ff;
126 }
127
128 /* offset for start of dictionary word */
129 wordoffset = get_next_bits(data_in, 0x0a);
130 if(wordoffset == 0)
131 return;
132
133 /* length of dictionary word used */
134 wordlen = get_next_bits(data_in, 0x04) + 1;
135 for (i = 0; i <= wordlen ; i++) {
136 /* lookup dictionary byte */
137 byte = buf[(wordoffset + i) & 0x3ff];
138 write_byte(byte, data_out);
139 /* Save byte in buffer, to be reused later */
140 buf[pos] = byte;
141 pos = (pos + 1) & 0x3ff;
142 }
143 }
144 }
145
146 void set_next_bit(unsigned char *buf, unsigned int set, unsigned int *currbit) {
147 unsigned char *pos;
148 unsigned char bitpos;
149
150 if (set) {
151 pos = buf + ((*currbit) / 8);
152 bitpos = 0x80 >> ((*currbit) % 8);
153 *pos |= bitpos;
154 }
155
156 *currbit = *currbit + 1;
157 }
158
159 void write_bits(unsigned char *buf, unsigned int data, unsigned int bits, unsigned int *currbit) {
160 int i;
161 unsigned int bitpos;
162
163 bitpos = 1 << (bits - 1);
164
165 for (i = 0; i < bits; i++) {
166 set_next_bit(buf, data & bitpos, currbit);
167 bitpos >>= 1;
168 }
169 }
170
171 unsigned char *compress_lz(unsigned char *inbuf, int inlen, int *outlen)
172 {
173 unsigned char *end = inbuf + inlen;
174 unsigned char *outbuf;
175 unsigned char window[1024];
176 int pos = 0;
177 int fill = 0;
178 unsigned int currbit = 0;
179 int offset;
180 int wordlen;
181 int found;
182 int i;
183
184 if ((outbuf = malloc((inlen * 2) + 4)) == NULL) {
185 perror("malloc");
186 }
187
188 *((unsigned int*)outbuf) = LZ_MAGIC;
189 currbit = 8 * 8;
190
191 while(inbuf < end) {
192 found = 0;
193 for (wordlen = 17; wordlen > 1; wordlen--) {
194 for (offset = 1; offset < ((fill < 1023) ? fill : 1023); offset++) {
195 if ((fill < 1023) &&
196 (wordlen + offset > fill))
197 break;
198
199 for (i = 0; i < wordlen; i++) {
200 if (inbuf[i] != window[(offset + i) & 0x3ff]) {
201 break;
202 }
203 }
204 if (i == wordlen)
205 found = 1;
206 }
207 if (found)
208 break;
209 }
210
211 if (found) {
212 write_bits(outbuf, 0x00, 0x01, &currbit);
213 write_bits(outbuf, offset, 0x0a, &currbit);
214 write_bits(outbuf, wordlen - 1, 0x04, &currbit);
215 for (i = 0; i < wordlen; i++) {
216 window[pos] = *(inbuf + i);
217 pos = (pos + 1) & 0x3ff;
218 }
219 inbuf += wordlen;
220
221 if (fill < sizeof(window))
222 fill += wordlen;
223 } else {
224 write_bits(outbuf, 0x01, 0x01, &currbit);
225 write_bits(outbuf, *inbuf, 0x08, &currbit);
226 window[pos] = *inbuf;
227 pos = (pos + 1) & 0x3ff;
228 inbuf++;
229 if (fill < sizeof(window))
230 fill++;
231 }
232 }
233
234 write_bits(outbuf, 0x00, 0x01, &currbit);
235 write_bits(outbuf, 0x00, 0x0a, &currbit);
236
237 *outlen = (currbit / 8) + 1;
238
239 *((unsigned int*)(outbuf + 4)) = *outlen;
240
241 return outbuf;
242 }
243
244 /* Checksum is only used for the compressed firmware in 'firmware' */
245 unsigned int crc_check(unsigned char *buf, unsigned int len, unsigned int magic)
246 {
247 unsigned int file_crc;
248 unsigned int my_len;
249 unsigned int crc;
250 unsigned int my_magic;
251
252 my_len = *((unsigned int*)(buf + 0x20));
253 my_magic = *((unsigned int*)(buf + 0x24));
254
255 if (my_magic != magic) {
256 printf("\nmagic: 0x%08x <-> 0x%08x\n", my_magic, magic);
257 return 2;
258 }
259
260 if (len < my_len)
261 return 3;
262
263 crc = ~rsb_crc(~0x00, buf, len);
264 file_crc = *((unsigned int*)(buf + len));
265
266 if (file_crc != crc) {
267 printf("\nChecksums: 0x%08x <-> 0x%08x!\n", crc, file_crc);
268 return 4;
269 }
270
271 return 0;
272 }
273
274 void extract_lz_file(unsigned char *inbuf, unsigned char *name, unsigned char check_crc)
275 {
276 unsigned int len;
277 unsigned char *outbuf;
278 struct data_in_s data_in;
279 struct data_out_s data_out;
280
281 if (*((unsigned int*)inbuf) != LZ_MAGIC)
282 err_exit(__func__);
283
284 len = *((unsigned int*)(inbuf + 4));
285 printf(", length: %d", len);
286
287 if ((outbuf = malloc(len)) == NULL) {
288 perror("malloc");
289 exit(1);
290 }
291
292 bzero(outbuf, len);
293
294 data_in.start = inbuf + 8;
295 data_in.stop = inbuf + len;
296 data_in.byte = 0x00;
297 data_in.bitpos = 0x80;
298
299 data_out.pos = outbuf;
300 data_out.end = outbuf + len;
301
302 lz_expand(&data_in, &data_out);
303
304 if (check_crc) {
305 unsigned int crclen;
306 int ret;
307
308 crclen = *((unsigned int*)(outbuf + 0x20));
309
310 if ((ret = crc_check(outbuf, crclen, 0x46335053)) != 0) {
311 printf("crc_check return: %d\n", ret);
312 err_exit(__func__);
313 }
314 }
315 write_file(extracted_file((char*)name), outbuf, len);
316
317 free(outbuf);
318 }
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