ia64/xen-unstable

view xen/common/lzo.c @ 19835:edfdeb150f27

Fix buildsystem to detect udev > version 124

udev removed the udevinfo symlink from versions higher than 123 and
xen's build-system could not detect if udev is in place and has the
required version.

Signed-off-by: Marc-A. Dahlhaus <mad@wol.de>
author Keir Fraser <keir.fraser@citrix.com>
date Thu Jun 25 13:02:37 2009 +0100 (2009-06-25)
parents f210a633571c
children
line source
1 /*
2 * lzo.c -- LZO1X Compressor from MiniLZO
3 *
4 * Copyright (C) 1996-2005 Markus F.X.J. Oberhumer <markus@oberhumer.com>
5 *
6 * The full LZO package can be found at:
7 * http://www.oberhumer.com/opensource/lzo/
8 *
9 * Adapted for Xen (files combined and syntactic/header changes) by:
10 * Dan Magenheimer <dan.magenheimer@oracle.com>
11 *
12 */
14 /*
15 * lzodefs.h -- architecture, OS and compiler specific defines
16 *
17 * Copyright (C) 1996-2005 Markus F.X.J. Oberhumer <markus@oberhumer.com>
18 *
19 * The full LZO package can be found at:
20 * http://www.oberhumer.com/opensource/lzo/
21 *
22 * Changed for kernel use by:
23 * Nitin Gupta <nitingupta910@gmail.com>
24 * Richard Purdie <rpurdie@openedhand.com>
25 */
27 #define LZO_VERSION 0x2020
28 #define LZO_VERSION_STRING "2.02"
29 #define LZO_VERSION_DATE "Oct 17 2005"
31 #define M1_MAX_OFFSET 0x0400
32 #define M2_MAX_OFFSET 0x0800
33 #define M3_MAX_OFFSET 0x4000
34 #define M4_MAX_OFFSET 0xbfff
36 #define M1_MIN_LEN 2
37 #define M1_MAX_LEN 2
38 #define M2_MIN_LEN 3
39 #define M2_MAX_LEN 8
40 #define M3_MIN_LEN 3
41 #define M3_MAX_LEN 33
42 #define M4_MIN_LEN 3
43 #define M4_MAX_LEN 9
45 #define M1_MARKER 0
46 #define M2_MARKER 64
47 #define M3_MARKER 32
48 #define M4_MARKER 16
50 #define D_BITS 14
51 #define D_MASK ((1u << D_BITS) - 1)
52 #define D_HIGH ((D_MASK >> 1) + 1)
54 #define DX2(p, s1, s2) (((((size_t)((p)[2]) << (s2)) ^ (p)[1]) \
55 << (s1)) ^ (p)[0])
56 #define DX3(p, s1, s2, s3) ((DX2((p)+1, s2, s3) << (s1)) ^ (p)[0])
58 /*
59 * LZO1X Compressor from MiniLZO
60 *
61 * Copyright (C) 1996-2005 Markus F.X.J. Oberhumer <markus@oberhumer.com>
62 *
63 * The full LZO package can be found at:
64 * http://www.oberhumer.com/opensource/lzo/
65 *
66 * Changed for kernel use by:
67 * Nitin Gupta <nitingupta910@gmail.com>
68 * Richard Purdie <rpurdie@openedhand.com>
69 */
71 #include <xen/types.h>
72 #include <xen/lzo.h>
73 #define get_unaligned(_p) (*(_p))
74 #define put_unaligned(_val,_p) (*(_p)=_val)
75 #define get_unaligned_le16(_p) (*(u16 *)(_p))
77 static noinline size_t
78 _lzo1x_1_do_compress(const unsigned char *in, size_t in_len,
79 unsigned char *out, size_t *out_len, void *wrkmem)
80 {
81 const unsigned char * const in_end = in + in_len;
82 const unsigned char * const ip_end = in + in_len - M2_MAX_LEN - 5;
83 const unsigned char ** const dict = wrkmem;
84 const unsigned char *ip = in, *ii = ip;
85 const unsigned char *end, *m, *m_pos;
86 size_t m_off, m_len, dindex;
87 unsigned char *op = out;
89 ip += 4;
91 for (;;) {
92 dindex = ((size_t)(0x21 * DX3(ip, 5, 5, 6)) >> 5) & D_MASK;
93 m_pos = dict[dindex];
95 if (m_pos < in)
96 goto literal;
98 if (ip == m_pos || ((size_t)(ip - m_pos) > M4_MAX_OFFSET))
99 goto literal;
101 m_off = ip - m_pos;
102 if (m_off <= M2_MAX_OFFSET || m_pos[3] == ip[3])
103 goto try_match;
105 dindex = (dindex & (D_MASK & 0x7ff)) ^ (D_HIGH | 0x1f);
106 m_pos = dict[dindex];
108 if (m_pos < in)
109 goto literal;
111 if (ip == m_pos || ((size_t)(ip - m_pos) > M4_MAX_OFFSET))
112 goto literal;
114 m_off = ip - m_pos;
115 if (m_off <= M2_MAX_OFFSET || m_pos[3] == ip[3])
116 goto try_match;
118 goto literal;
120 try_match:
121 if (get_unaligned((const unsigned short *)m_pos)
122 == get_unaligned((const unsigned short *)ip)) {
123 if (likely(m_pos[2] == ip[2]))
124 goto match;
125 }
127 literal:
128 dict[dindex] = ip;
129 ++ip;
130 if (unlikely(ip >= ip_end))
131 break;
132 continue;
134 match:
135 dict[dindex] = ip;
136 if (ip != ii) {
137 size_t t = ip - ii;
139 if (t <= 3) {
140 op[-2] |= t;
141 } else if (t <= 18) {
142 *op++ = (t - 3);
143 } else {
144 size_t tt = t - 18;
146 *op++ = 0;
147 while (tt > 255) {
148 tt -= 255;
149 *op++ = 0;
150 }
151 *op++ = tt;
152 }
153 do {
154 *op++ = *ii++;
155 } while (--t > 0);
156 }
158 ip += 3;
159 if (m_pos[3] != *ip++ || m_pos[4] != *ip++
160 || m_pos[5] != *ip++ || m_pos[6] != *ip++
161 || m_pos[7] != *ip++ || m_pos[8] != *ip++) {
162 --ip;
163 m_len = ip - ii;
165 if (m_off <= M2_MAX_OFFSET) {
166 m_off -= 1;
167 *op++ = (((m_len - 1) << 5)
168 | ((m_off & 7) << 2));
169 *op++ = (m_off >> 3);
170 } else if (m_off <= M3_MAX_OFFSET) {
171 m_off -= 1;
172 *op++ = (M3_MARKER | (m_len - 2));
173 goto m3_m4_offset;
174 } else {
175 m_off -= 0x4000;
177 *op++ = (M4_MARKER | ((m_off & 0x4000) >> 11)
178 | (m_len - 2));
179 goto m3_m4_offset;
180 }
181 } else {
182 end = in_end;
183 m = m_pos + M2_MAX_LEN + 1;
185 while (ip < end && *m == *ip) {
186 m++;
187 ip++;
188 }
189 m_len = ip - ii;
191 if (m_off <= M3_MAX_OFFSET) {
192 m_off -= 1;
193 if (m_len <= 33) {
194 *op++ = (M3_MARKER | (m_len - 2));
195 } else {
196 m_len -= 33;
197 *op++ = M3_MARKER | 0;
198 goto m3_m4_len;
199 }
200 } else {
201 m_off -= 0x4000;
202 if (m_len <= M4_MAX_LEN) {
203 *op++ = (M4_MARKER
204 | ((m_off & 0x4000) >> 11)
205 | (m_len - 2));
206 } else {
207 m_len -= M4_MAX_LEN;
208 *op++ = (M4_MARKER
209 | ((m_off & 0x4000) >> 11));
210 m3_m4_len:
211 while (m_len > 255) {
212 m_len -= 255;
213 *op++ = 0;
214 }
216 *op++ = (m_len);
217 }
218 }
219 m3_m4_offset:
220 *op++ = ((m_off & 63) << 2);
221 *op++ = (m_off >> 6);
222 }
224 ii = ip;
225 if (unlikely(ip >= ip_end))
226 break;
227 }
229 *out_len = op - out;
230 return in_end - ii;
231 }
233 int lzo1x_1_compress(const unsigned char *in, size_t in_len, unsigned char *out,
234 size_t *out_len, void *wrkmem)
235 {
236 const unsigned char *ii;
237 unsigned char *op = out;
238 size_t t;
240 if (unlikely(in_len <= M2_MAX_LEN + 5)) {
241 t = in_len;
242 } else {
243 t = _lzo1x_1_do_compress(in, in_len, op, out_len, wrkmem);
244 op += *out_len;
245 }
247 if (t > 0) {
248 ii = in + in_len - t;
250 if (op == out && t <= 238) {
251 *op++ = (17 + t);
252 } else if (t <= 3) {
253 op[-2] |= t;
254 } else if (t <= 18) {
255 *op++ = (t - 3);
256 } else {
257 size_t tt = t - 18;
259 *op++ = 0;
260 while (tt > 255) {
261 tt -= 255;
262 *op++ = 0;
263 }
265 *op++ = tt;
266 }
267 do {
268 *op++ = *ii++;
269 } while (--t > 0);
270 }
272 *op++ = M4_MARKER | 1;
273 *op++ = 0;
274 *op++ = 0;
276 *out_len = op - out;
277 return LZO_E_OK;
278 }
280 /*
281 * LZO1X Decompressor from MiniLZO
282 *
283 * Copyright (C) 1996-2005 Markus F.X.J. Oberhumer <markus@oberhumer.com>
284 *
285 * The full LZO package can be found at:
286 * http://www.oberhumer.com/opensource/lzo/
287 *
288 * Changed for kernel use by:
289 * Nitin Gupta <nitingupta910@gmail.com>
290 * Richard Purdie <rpurdie@openedhand.com>
291 */
293 #define HAVE_IP(x, ip_end, ip) ((size_t)(ip_end - ip) < (x))
294 #define HAVE_OP(x, op_end, op) ((size_t)(op_end - op) < (x))
295 #define HAVE_LB(m_pos, out, op) (m_pos < out || m_pos >= op)
297 #define COPY4(dst, src) \
298 put_unaligned(get_unaligned((const u32 *)(src)), (u32 *)(dst))
300 int lzo1x_decompress_safe(const unsigned char *in, size_t in_len,
301 unsigned char *out, size_t *out_len)
302 {
303 const unsigned char * const ip_end = in + in_len;
304 unsigned char * const op_end = out + *out_len;
305 const unsigned char *ip = in, *m_pos;
306 unsigned char *op = out;
307 size_t t;
309 *out_len = 0;
311 if (*ip > 17) {
312 t = *ip++ - 17;
313 if (t < 4)
314 goto match_next;
315 if (HAVE_OP(t, op_end, op))
316 goto output_overrun;
317 if (HAVE_IP(t + 1, ip_end, ip))
318 goto input_overrun;
319 do {
320 *op++ = *ip++;
321 } while (--t > 0);
322 goto first_literal_run;
323 }
325 while ((ip < ip_end)) {
326 t = *ip++;
327 if (t >= 16)
328 goto match;
329 if (t == 0) {
330 if (HAVE_IP(1, ip_end, ip))
331 goto input_overrun;
332 while (*ip == 0) {
333 t += 255;
334 ip++;
335 if (HAVE_IP(1, ip_end, ip))
336 goto input_overrun;
337 }
338 t += 15 + *ip++;
339 }
340 if (HAVE_OP(t + 3, op_end, op))
341 goto output_overrun;
342 if (HAVE_IP(t + 4, ip_end, ip))
343 goto input_overrun;
345 COPY4(op, ip);
346 op += 4;
347 ip += 4;
348 if (--t > 0) {
349 if (t >= 4) {
350 do {
351 COPY4(op, ip);
352 op += 4;
353 ip += 4;
354 t -= 4;
355 } while (t >= 4);
356 if (t > 0) {
357 do {
358 *op++ = *ip++;
359 } while (--t > 0);
360 }
361 } else {
362 do {
363 *op++ = *ip++;
364 } while (--t > 0);
365 }
366 }
368 first_literal_run:
369 t = *ip++;
370 if (t >= 16)
371 goto match;
372 m_pos = op - (1 + M2_MAX_OFFSET);
373 m_pos -= t >> 2;
374 m_pos -= *ip++ << 2;
376 if (HAVE_LB(m_pos, out, op))
377 goto lookbehind_overrun;
379 if (HAVE_OP(3, op_end, op))
380 goto output_overrun;
381 *op++ = *m_pos++;
382 *op++ = *m_pos++;
383 *op++ = *m_pos;
385 goto match_done;
387 do {
388 match:
389 if (t >= 64) {
390 m_pos = op - 1;
391 m_pos -= (t >> 2) & 7;
392 m_pos -= *ip++ << 3;
393 t = (t >> 5) - 1;
394 if (HAVE_LB(m_pos, out, op))
395 goto lookbehind_overrun;
396 if (HAVE_OP(t + 3 - 1, op_end, op))
397 goto output_overrun;
398 goto copy_match;
399 } else if (t >= 32) {
400 t &= 31;
401 if (t == 0) {
402 if (HAVE_IP(1, ip_end, ip))
403 goto input_overrun;
404 while (*ip == 0) {
405 t += 255;
406 ip++;
407 if (HAVE_IP(1, ip_end, ip))
408 goto input_overrun;
409 }
410 t += 31 + *ip++;
411 }
412 m_pos = op - 1;
413 m_pos -= get_unaligned_le16(ip) >> 2;
414 ip += 2;
415 } else if (t >= 16) {
416 m_pos = op;
417 m_pos -= (t & 8) << 11;
419 t &= 7;
420 if (t == 0) {
421 if (HAVE_IP(1, ip_end, ip))
422 goto input_overrun;
423 while (*ip == 0) {
424 t += 255;
425 ip++;
426 if (HAVE_IP(1, ip_end, ip))
427 goto input_overrun;
428 }
429 t += 7 + *ip++;
430 }
431 m_pos -= get_unaligned_le16(ip) >> 2;
432 ip += 2;
433 if (m_pos == op)
434 goto eof_found;
435 m_pos -= 0x4000;
436 } else {
437 m_pos = op - 1;
438 m_pos -= t >> 2;
439 m_pos -= *ip++ << 2;
441 if (HAVE_LB(m_pos, out, op))
442 goto lookbehind_overrun;
443 if (HAVE_OP(2, op_end, op))
444 goto output_overrun;
446 *op++ = *m_pos++;
447 *op++ = *m_pos;
448 goto match_done;
449 }
451 if (HAVE_LB(m_pos, out, op))
452 goto lookbehind_overrun;
453 if (HAVE_OP(t + 3 - 1, op_end, op))
454 goto output_overrun;
456 if (t >= 2 * 4 - (3 - 1) && (op - m_pos) >= 4) {
457 COPY4(op, m_pos);
458 op += 4;
459 m_pos += 4;
460 t -= 4 - (3 - 1);
461 do {
462 COPY4(op, m_pos);
463 op += 4;
464 m_pos += 4;
465 t -= 4;
466 } while (t >= 4);
467 if (t > 0)
468 do {
469 *op++ = *m_pos++;
470 } while (--t > 0);
471 } else {
472 copy_match:
473 *op++ = *m_pos++;
474 *op++ = *m_pos++;
475 do {
476 *op++ = *m_pos++;
477 } while (--t > 0);
478 }
479 match_done:
480 t = ip[-2] & 3;
481 if (t == 0)
482 break;
483 match_next:
484 if (HAVE_OP(t, op_end, op))
485 goto output_overrun;
486 if (HAVE_IP(t + 1, ip_end, ip))
487 goto input_overrun;
489 *op++ = *ip++;
490 if (t > 1) {
491 *op++ = *ip++;
492 if (t > 2)
493 *op++ = *ip++;
494 }
496 t = *ip++;
497 } while (ip < ip_end);
498 }
500 *out_len = op - out;
501 return LZO_E_EOF_NOT_FOUND;
503 eof_found:
504 *out_len = op - out;
505 return (ip == ip_end ? LZO_E_OK :
506 (ip < ip_end ? LZO_E_INPUT_NOT_CONSUMED : LZO_E_INPUT_OVERRUN));
507 input_overrun:
508 *out_len = op - out;
509 return LZO_E_INPUT_OVERRUN;
511 output_overrun:
512 *out_len = op - out;
513 return LZO_E_OUTPUT_OVERRUN;
515 lookbehind_overrun:
516 *out_len = op - out;
517 return LZO_E_LOOKBEHIND_OVERRUN;
518 }