debuggers.hg

annotate xen/common/lzo.c @ 22848:6341fe0f4e5a

Added tag 4.1.0-rc2 for changeset 9dca60d88c63
author Keir Fraser <keir@xen.org>
date Tue Jan 25 14:06:55 2011 +0000 (2011-01-25)
parents f210a633571c
children
rev   line source
keir@19684 1 /*
keir@19684 2 * lzo.c -- LZO1X Compressor from MiniLZO
keir@19684 3 *
keir@19684 4 * Copyright (C) 1996-2005 Markus F.X.J. Oberhumer <markus@oberhumer.com>
keir@19684 5 *
keir@19684 6 * The full LZO package can be found at:
keir@19684 7 * http://www.oberhumer.com/opensource/lzo/
keir@19684 8 *
keir@19684 9 * Adapted for Xen (files combined and syntactic/header changes) by:
keir@19684 10 * Dan Magenheimer <dan.magenheimer@oracle.com>
keir@19684 11 *
keir@19684 12 */
keir@19684 13
keir@19684 14 /*
keir@19684 15 * lzodefs.h -- architecture, OS and compiler specific defines
keir@19684 16 *
keir@19684 17 * Copyright (C) 1996-2005 Markus F.X.J. Oberhumer <markus@oberhumer.com>
keir@19684 18 *
keir@19684 19 * The full LZO package can be found at:
keir@19684 20 * http://www.oberhumer.com/opensource/lzo/
keir@19684 21 *
keir@19684 22 * Changed for kernel use by:
keir@19684 23 * Nitin Gupta <nitingupta910@gmail.com>
keir@19684 24 * Richard Purdie <rpurdie@openedhand.com>
keir@19684 25 */
keir@19684 26
keir@19684 27 #define LZO_VERSION 0x2020
keir@19684 28 #define LZO_VERSION_STRING "2.02"
keir@19684 29 #define LZO_VERSION_DATE "Oct 17 2005"
keir@19684 30
keir@19684 31 #define M1_MAX_OFFSET 0x0400
keir@19684 32 #define M2_MAX_OFFSET 0x0800
keir@19684 33 #define M3_MAX_OFFSET 0x4000
keir@19684 34 #define M4_MAX_OFFSET 0xbfff
keir@19684 35
keir@19684 36 #define M1_MIN_LEN 2
keir@19684 37 #define M1_MAX_LEN 2
keir@19684 38 #define M2_MIN_LEN 3
keir@19684 39 #define M2_MAX_LEN 8
keir@19684 40 #define M3_MIN_LEN 3
keir@19684 41 #define M3_MAX_LEN 33
keir@19684 42 #define M4_MIN_LEN 3
keir@19684 43 #define M4_MAX_LEN 9
keir@19684 44
keir@19684 45 #define M1_MARKER 0
keir@19684 46 #define M2_MARKER 64
keir@19684 47 #define M3_MARKER 32
keir@19684 48 #define M4_MARKER 16
keir@19684 49
keir@19684 50 #define D_BITS 14
keir@19684 51 #define D_MASK ((1u << D_BITS) - 1)
keir@19684 52 #define D_HIGH ((D_MASK >> 1) + 1)
keir@19684 53
keir@19684 54 #define DX2(p, s1, s2) (((((size_t)((p)[2]) << (s2)) ^ (p)[1]) \
keir@19684 55 << (s1)) ^ (p)[0])
keir@19684 56 #define DX3(p, s1, s2, s3) ((DX2((p)+1, s2, s3) << (s1)) ^ (p)[0])
keir@19684 57
keir@19684 58 /*
keir@19684 59 * LZO1X Compressor from MiniLZO
keir@19684 60 *
keir@19684 61 * Copyright (C) 1996-2005 Markus F.X.J. Oberhumer <markus@oberhumer.com>
keir@19684 62 *
keir@19684 63 * The full LZO package can be found at:
keir@19684 64 * http://www.oberhumer.com/opensource/lzo/
keir@19684 65 *
keir@19684 66 * Changed for kernel use by:
keir@19684 67 * Nitin Gupta <nitingupta910@gmail.com>
keir@19684 68 * Richard Purdie <rpurdie@openedhand.com>
keir@19684 69 */
keir@19684 70
keir@19684 71 #include <xen/types.h>
keir@19684 72 #include <xen/lzo.h>
keir@19684 73 #define get_unaligned(_p) (*(_p))
keir@19684 74 #define put_unaligned(_val,_p) (*(_p)=_val)
keir@19684 75 #define get_unaligned_le16(_p) (*(u16 *)(_p))
keir@19684 76
keir@19684 77 static noinline size_t
keir@19684 78 _lzo1x_1_do_compress(const unsigned char *in, size_t in_len,
keir@19684 79 unsigned char *out, size_t *out_len, void *wrkmem)
keir@19684 80 {
keir@19684 81 const unsigned char * const in_end = in + in_len;
keir@19684 82 const unsigned char * const ip_end = in + in_len - M2_MAX_LEN - 5;
keir@19684 83 const unsigned char ** const dict = wrkmem;
keir@19684 84 const unsigned char *ip = in, *ii = ip;
keir@19684 85 const unsigned char *end, *m, *m_pos;
keir@19684 86 size_t m_off, m_len, dindex;
keir@19684 87 unsigned char *op = out;
keir@19684 88
keir@19684 89 ip += 4;
keir@19684 90
keir@19684 91 for (;;) {
keir@19684 92 dindex = ((size_t)(0x21 * DX3(ip, 5, 5, 6)) >> 5) & D_MASK;
keir@19684 93 m_pos = dict[dindex];
keir@19684 94
keir@19684 95 if (m_pos < in)
keir@19684 96 goto literal;
keir@19684 97
keir@19684 98 if (ip == m_pos || ((size_t)(ip - m_pos) > M4_MAX_OFFSET))
keir@19684 99 goto literal;
keir@19684 100
keir@19684 101 m_off = ip - m_pos;
keir@19684 102 if (m_off <= M2_MAX_OFFSET || m_pos[3] == ip[3])
keir@19684 103 goto try_match;
keir@19684 104
keir@19684 105 dindex = (dindex & (D_MASK & 0x7ff)) ^ (D_HIGH | 0x1f);
keir@19684 106 m_pos = dict[dindex];
keir@19684 107
keir@19684 108 if (m_pos < in)
keir@19684 109 goto literal;
keir@19684 110
keir@19684 111 if (ip == m_pos || ((size_t)(ip - m_pos) > M4_MAX_OFFSET))
keir@19684 112 goto literal;
keir@19684 113
keir@19684 114 m_off = ip - m_pos;
keir@19684 115 if (m_off <= M2_MAX_OFFSET || m_pos[3] == ip[3])
keir@19684 116 goto try_match;
keir@19684 117
keir@19684 118 goto literal;
keir@19684 119
keir@19684 120 try_match:
keir@19684 121 if (get_unaligned((const unsigned short *)m_pos)
keir@19684 122 == get_unaligned((const unsigned short *)ip)) {
keir@19684 123 if (likely(m_pos[2] == ip[2]))
keir@19684 124 goto match;
keir@19684 125 }
keir@19684 126
keir@19684 127 literal:
keir@19684 128 dict[dindex] = ip;
keir@19684 129 ++ip;
keir@19684 130 if (unlikely(ip >= ip_end))
keir@19684 131 break;
keir@19684 132 continue;
keir@19684 133
keir@19684 134 match:
keir@19684 135 dict[dindex] = ip;
keir@19684 136 if (ip != ii) {
keir@19684 137 size_t t = ip - ii;
keir@19684 138
keir@19684 139 if (t <= 3) {
keir@19684 140 op[-2] |= t;
keir@19684 141 } else if (t <= 18) {
keir@19684 142 *op++ = (t - 3);
keir@19684 143 } else {
keir@19684 144 size_t tt = t - 18;
keir@19684 145
keir@19684 146 *op++ = 0;
keir@19684 147 while (tt > 255) {
keir@19684 148 tt -= 255;
keir@19684 149 *op++ = 0;
keir@19684 150 }
keir@19684 151 *op++ = tt;
keir@19684 152 }
keir@19684 153 do {
keir@19684 154 *op++ = *ii++;
keir@19684 155 } while (--t > 0);
keir@19684 156 }
keir@19684 157
keir@19684 158 ip += 3;
keir@19684 159 if (m_pos[3] != *ip++ || m_pos[4] != *ip++
keir@19684 160 || m_pos[5] != *ip++ || m_pos[6] != *ip++
keir@19684 161 || m_pos[7] != *ip++ || m_pos[8] != *ip++) {
keir@19684 162 --ip;
keir@19684 163 m_len = ip - ii;
keir@19684 164
keir@19684 165 if (m_off <= M2_MAX_OFFSET) {
keir@19684 166 m_off -= 1;
keir@19684 167 *op++ = (((m_len - 1) << 5)
keir@19684 168 | ((m_off & 7) << 2));
keir@19684 169 *op++ = (m_off >> 3);
keir@19684 170 } else if (m_off <= M3_MAX_OFFSET) {
keir@19684 171 m_off -= 1;
keir@19684 172 *op++ = (M3_MARKER | (m_len - 2));
keir@19684 173 goto m3_m4_offset;
keir@19684 174 } else {
keir@19684 175 m_off -= 0x4000;
keir@19684 176
keir@19684 177 *op++ = (M4_MARKER | ((m_off & 0x4000) >> 11)
keir@19684 178 | (m_len - 2));
keir@19684 179 goto m3_m4_offset;
keir@19684 180 }
keir@19684 181 } else {
keir@19684 182 end = in_end;
keir@19684 183 m = m_pos + M2_MAX_LEN + 1;
keir@19684 184
keir@19684 185 while (ip < end && *m == *ip) {
keir@19684 186 m++;
keir@19684 187 ip++;
keir@19684 188 }
keir@19684 189 m_len = ip - ii;
keir@19684 190
keir@19684 191 if (m_off <= M3_MAX_OFFSET) {
keir@19684 192 m_off -= 1;
keir@19684 193 if (m_len <= 33) {
keir@19684 194 *op++ = (M3_MARKER | (m_len - 2));
keir@19684 195 } else {
keir@19684 196 m_len -= 33;
keir@19684 197 *op++ = M3_MARKER | 0;
keir@19684 198 goto m3_m4_len;
keir@19684 199 }
keir@19684 200 } else {
keir@19684 201 m_off -= 0x4000;
keir@19684 202 if (m_len <= M4_MAX_LEN) {
keir@19684 203 *op++ = (M4_MARKER
keir@19684 204 | ((m_off & 0x4000) >> 11)
keir@19684 205 | (m_len - 2));
keir@19684 206 } else {
keir@19684 207 m_len -= M4_MAX_LEN;
keir@19684 208 *op++ = (M4_MARKER
keir@19684 209 | ((m_off & 0x4000) >> 11));
keir@19684 210 m3_m4_len:
keir@19684 211 while (m_len > 255) {
keir@19684 212 m_len -= 255;
keir@19684 213 *op++ = 0;
keir@19684 214 }
keir@19684 215
keir@19684 216 *op++ = (m_len);
keir@19684 217 }
keir@19684 218 }
keir@19684 219 m3_m4_offset:
keir@19684 220 *op++ = ((m_off & 63) << 2);
keir@19684 221 *op++ = (m_off >> 6);
keir@19684 222 }
keir@19684 223
keir@19684 224 ii = ip;
keir@19684 225 if (unlikely(ip >= ip_end))
keir@19684 226 break;
keir@19684 227 }
keir@19684 228
keir@19684 229 *out_len = op - out;
keir@19684 230 return in_end - ii;
keir@19684 231 }
keir@19684 232
keir@19684 233 int lzo1x_1_compress(const unsigned char *in, size_t in_len, unsigned char *out,
keir@19684 234 size_t *out_len, void *wrkmem)
keir@19684 235 {
keir@19684 236 const unsigned char *ii;
keir@19684 237 unsigned char *op = out;
keir@19684 238 size_t t;
keir@19684 239
keir@19684 240 if (unlikely(in_len <= M2_MAX_LEN + 5)) {
keir@19684 241 t = in_len;
keir@19684 242 } else {
keir@19684 243 t = _lzo1x_1_do_compress(in, in_len, op, out_len, wrkmem);
keir@19684 244 op += *out_len;
keir@19684 245 }
keir@19684 246
keir@19684 247 if (t > 0) {
keir@19684 248 ii = in + in_len - t;
keir@19684 249
keir@19684 250 if (op == out && t <= 238) {
keir@19684 251 *op++ = (17 + t);
keir@19684 252 } else if (t <= 3) {
keir@19684 253 op[-2] |= t;
keir@19684 254 } else if (t <= 18) {
keir@19684 255 *op++ = (t - 3);
keir@19684 256 } else {
keir@19684 257 size_t tt = t - 18;
keir@19684 258
keir@19684 259 *op++ = 0;
keir@19684 260 while (tt > 255) {
keir@19684 261 tt -= 255;
keir@19684 262 *op++ = 0;
keir@19684 263 }
keir@19684 264
keir@19684 265 *op++ = tt;
keir@19684 266 }
keir@19684 267 do {
keir@19684 268 *op++ = *ii++;
keir@19684 269 } while (--t > 0);
keir@19684 270 }
keir@19684 271
keir@19684 272 *op++ = M4_MARKER | 1;
keir@19684 273 *op++ = 0;
keir@19684 274 *op++ = 0;
keir@19684 275
keir@19684 276 *out_len = op - out;
keir@19684 277 return LZO_E_OK;
keir@19684 278 }
keir@19684 279
keir@19684 280 /*
keir@19684 281 * LZO1X Decompressor from MiniLZO
keir@19684 282 *
keir@19684 283 * Copyright (C) 1996-2005 Markus F.X.J. Oberhumer <markus@oberhumer.com>
keir@19684 284 *
keir@19684 285 * The full LZO package can be found at:
keir@19684 286 * http://www.oberhumer.com/opensource/lzo/
keir@19684 287 *
keir@19684 288 * Changed for kernel use by:
keir@19684 289 * Nitin Gupta <nitingupta910@gmail.com>
keir@19684 290 * Richard Purdie <rpurdie@openedhand.com>
keir@19684 291 */
keir@19684 292
keir@19684 293 #define HAVE_IP(x, ip_end, ip) ((size_t)(ip_end - ip) < (x))
keir@19684 294 #define HAVE_OP(x, op_end, op) ((size_t)(op_end - op) < (x))
keir@19684 295 #define HAVE_LB(m_pos, out, op) (m_pos < out || m_pos >= op)
keir@19684 296
keir@19684 297 #define COPY4(dst, src) \
keir@19684 298 put_unaligned(get_unaligned((const u32 *)(src)), (u32 *)(dst))
keir@19684 299
keir@19684 300 int lzo1x_decompress_safe(const unsigned char *in, size_t in_len,
keir@19684 301 unsigned char *out, size_t *out_len)
keir@19684 302 {
keir@19684 303 const unsigned char * const ip_end = in + in_len;
keir@19684 304 unsigned char * const op_end = out + *out_len;
keir@19684 305 const unsigned char *ip = in, *m_pos;
keir@19684 306 unsigned char *op = out;
keir@19684 307 size_t t;
keir@19684 308
keir@19684 309 *out_len = 0;
keir@19684 310
keir@19684 311 if (*ip > 17) {
keir@19684 312 t = *ip++ - 17;
keir@19684 313 if (t < 4)
keir@19684 314 goto match_next;
keir@19684 315 if (HAVE_OP(t, op_end, op))
keir@19684 316 goto output_overrun;
keir@19684 317 if (HAVE_IP(t + 1, ip_end, ip))
keir@19684 318 goto input_overrun;
keir@19684 319 do {
keir@19684 320 *op++ = *ip++;
keir@19684 321 } while (--t > 0);
keir@19684 322 goto first_literal_run;
keir@19684 323 }
keir@19684 324
keir@19684 325 while ((ip < ip_end)) {
keir@19684 326 t = *ip++;
keir@19684 327 if (t >= 16)
keir@19684 328 goto match;
keir@19684 329 if (t == 0) {
keir@19684 330 if (HAVE_IP(1, ip_end, ip))
keir@19684 331 goto input_overrun;
keir@19684 332 while (*ip == 0) {
keir@19684 333 t += 255;
keir@19684 334 ip++;
keir@19684 335 if (HAVE_IP(1, ip_end, ip))
keir@19684 336 goto input_overrun;
keir@19684 337 }
keir@19684 338 t += 15 + *ip++;
keir@19684 339 }
keir@19684 340 if (HAVE_OP(t + 3, op_end, op))
keir@19684 341 goto output_overrun;
keir@19684 342 if (HAVE_IP(t + 4, ip_end, ip))
keir@19684 343 goto input_overrun;
keir@19684 344
keir@19684 345 COPY4(op, ip);
keir@19684 346 op += 4;
keir@19684 347 ip += 4;
keir@19684 348 if (--t > 0) {
keir@19684 349 if (t >= 4) {
keir@19684 350 do {
keir@19684 351 COPY4(op, ip);
keir@19684 352 op += 4;
keir@19684 353 ip += 4;
keir@19684 354 t -= 4;
keir@19684 355 } while (t >= 4);
keir@19684 356 if (t > 0) {
keir@19684 357 do {
keir@19684 358 *op++ = *ip++;
keir@19684 359 } while (--t > 0);
keir@19684 360 }
keir@19684 361 } else {
keir@19684 362 do {
keir@19684 363 *op++ = *ip++;
keir@19684 364 } while (--t > 0);
keir@19684 365 }
keir@19684 366 }
keir@19684 367
keir@19684 368 first_literal_run:
keir@19684 369 t = *ip++;
keir@19684 370 if (t >= 16)
keir@19684 371 goto match;
keir@19684 372 m_pos = op - (1 + M2_MAX_OFFSET);
keir@19684 373 m_pos -= t >> 2;
keir@19684 374 m_pos -= *ip++ << 2;
keir@19684 375
keir@19684 376 if (HAVE_LB(m_pos, out, op))
keir@19684 377 goto lookbehind_overrun;
keir@19684 378
keir@19684 379 if (HAVE_OP(3, op_end, op))
keir@19684 380 goto output_overrun;
keir@19684 381 *op++ = *m_pos++;
keir@19684 382 *op++ = *m_pos++;
keir@19684 383 *op++ = *m_pos;
keir@19684 384
keir@19684 385 goto match_done;
keir@19684 386
keir@19684 387 do {
keir@19684 388 match:
keir@19684 389 if (t >= 64) {
keir@19684 390 m_pos = op - 1;
keir@19684 391 m_pos -= (t >> 2) & 7;
keir@19684 392 m_pos -= *ip++ << 3;
keir@19684 393 t = (t >> 5) - 1;
keir@19684 394 if (HAVE_LB(m_pos, out, op))
keir@19684 395 goto lookbehind_overrun;
keir@19684 396 if (HAVE_OP(t + 3 - 1, op_end, op))
keir@19684 397 goto output_overrun;
keir@19684 398 goto copy_match;
keir@19684 399 } else if (t >= 32) {
keir@19684 400 t &= 31;
keir@19684 401 if (t == 0) {
keir@19684 402 if (HAVE_IP(1, ip_end, ip))
keir@19684 403 goto input_overrun;
keir@19684 404 while (*ip == 0) {
keir@19684 405 t += 255;
keir@19684 406 ip++;
keir@19684 407 if (HAVE_IP(1, ip_end, ip))
keir@19684 408 goto input_overrun;
keir@19684 409 }
keir@19684 410 t += 31 + *ip++;
keir@19684 411 }
keir@19684 412 m_pos = op - 1;
keir@19684 413 m_pos -= get_unaligned_le16(ip) >> 2;
keir@19684 414 ip += 2;
keir@19684 415 } else if (t >= 16) {
keir@19684 416 m_pos = op;
keir@19684 417 m_pos -= (t & 8) << 11;
keir@19684 418
keir@19684 419 t &= 7;
keir@19684 420 if (t == 0) {
keir@19684 421 if (HAVE_IP(1, ip_end, ip))
keir@19684 422 goto input_overrun;
keir@19684 423 while (*ip == 0) {
keir@19684 424 t += 255;
keir@19684 425 ip++;
keir@19684 426 if (HAVE_IP(1, ip_end, ip))
keir@19684 427 goto input_overrun;
keir@19684 428 }
keir@19684 429 t += 7 + *ip++;
keir@19684 430 }
keir@19684 431 m_pos -= get_unaligned_le16(ip) >> 2;
keir@19684 432 ip += 2;
keir@19684 433 if (m_pos == op)
keir@19684 434 goto eof_found;
keir@19684 435 m_pos -= 0x4000;
keir@19684 436 } else {
keir@19684 437 m_pos = op - 1;
keir@19684 438 m_pos -= t >> 2;
keir@19684 439 m_pos -= *ip++ << 2;
keir@19684 440
keir@19684 441 if (HAVE_LB(m_pos, out, op))
keir@19684 442 goto lookbehind_overrun;
keir@19684 443 if (HAVE_OP(2, op_end, op))
keir@19684 444 goto output_overrun;
keir@19684 445
keir@19684 446 *op++ = *m_pos++;
keir@19684 447 *op++ = *m_pos;
keir@19684 448 goto match_done;
keir@19684 449 }
keir@19684 450
keir@19684 451 if (HAVE_LB(m_pos, out, op))
keir@19684 452 goto lookbehind_overrun;
keir@19684 453 if (HAVE_OP(t + 3 - 1, op_end, op))
keir@19684 454 goto output_overrun;
keir@19684 455
keir@19684 456 if (t >= 2 * 4 - (3 - 1) && (op - m_pos) >= 4) {
keir@19684 457 COPY4(op, m_pos);
keir@19684 458 op += 4;
keir@19684 459 m_pos += 4;
keir@19684 460 t -= 4 - (3 - 1);
keir@19684 461 do {
keir@19684 462 COPY4(op, m_pos);
keir@19684 463 op += 4;
keir@19684 464 m_pos += 4;
keir@19684 465 t -= 4;
keir@19684 466 } while (t >= 4);
keir@19684 467 if (t > 0)
keir@19684 468 do {
keir@19684 469 *op++ = *m_pos++;
keir@19684 470 } while (--t > 0);
keir@19684 471 } else {
keir@19684 472 copy_match:
keir@19684 473 *op++ = *m_pos++;
keir@19684 474 *op++ = *m_pos++;
keir@19684 475 do {
keir@19684 476 *op++ = *m_pos++;
keir@19684 477 } while (--t > 0);
keir@19684 478 }
keir@19684 479 match_done:
keir@19684 480 t = ip[-2] & 3;
keir@19684 481 if (t == 0)
keir@19684 482 break;
keir@19684 483 match_next:
keir@19684 484 if (HAVE_OP(t, op_end, op))
keir@19684 485 goto output_overrun;
keir@19684 486 if (HAVE_IP(t + 1, ip_end, ip))
keir@19684 487 goto input_overrun;
keir@19684 488
keir@19684 489 *op++ = *ip++;
keir@19684 490 if (t > 1) {
keir@19684 491 *op++ = *ip++;
keir@19684 492 if (t > 2)
keir@19684 493 *op++ = *ip++;
keir@19684 494 }
keir@19684 495
keir@19684 496 t = *ip++;
keir@19684 497 } while (ip < ip_end);
keir@19684 498 }
keir@19684 499
keir@19684 500 *out_len = op - out;
keir@19684 501 return LZO_E_EOF_NOT_FOUND;
keir@19684 502
keir@19684 503 eof_found:
keir@19684 504 *out_len = op - out;
keir@19684 505 return (ip == ip_end ? LZO_E_OK :
keir@19684 506 (ip < ip_end ? LZO_E_INPUT_NOT_CONSUMED : LZO_E_INPUT_OVERRUN));
keir@19684 507 input_overrun:
keir@19684 508 *out_len = op - out;
keir@19684 509 return LZO_E_INPUT_OVERRUN;
keir@19684 510
keir@19684 511 output_overrun:
keir@19684 512 *out_len = op - out;
keir@19684 513 return LZO_E_OUTPUT_OVERRUN;
keir@19684 514
keir@19684 515 lookbehind_overrun:
keir@19684 516 *out_len = op - out;
keir@19684 517 return LZO_E_LOOKBEHIND_OVERRUN;
keir@19684 518 }