linux/lib/decompress_unlzma.c
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   1/* Lzma decompressor for Linux kernel. Shamelessly snarfed
   2 *from busybox 1.1.1
   3 *
   4 *Linux kernel adaptation
   5 *Copyright (C) 2006  Alain < alain@knaff.lu >
   6 *
   7 *Based on small lzma deflate implementation/Small range coder
   8 *implementation for lzma.
   9 *Copyright (C) 2006  Aurelien Jacobs < aurel@gnuage.org >
  10 *
  11 *Based on LzmaDecode.c from the LZMA SDK 4.22 (http://www.7-zip.org/)
  12 *Copyright (C) 1999-2005  Igor Pavlov
  13 *
  14 *Copyrights of the parts, see headers below.
  15 *
  16 *
  17 *This program is free software; you can redistribute it and/or
  18 *modify it under the terms of the GNU Lesser General Public
  19 *License as published by the Free Software Foundation; either
  20 *version 2.1 of the License, or (at your option) any later version.
  21 *
  22 *This program is distributed in the hope that it will be useful,
  23 *but WITHOUT ANY WARRANTY; without even the implied warranty of
  24 *MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  25 *Lesser General Public License for more details.
  26 *
  27 *You should have received a copy of the GNU Lesser General Public
  28 *License along with this library; if not, write to the Free Software
  29 *Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  30 */
  31
  32#ifdef STATIC
  33#define PREBOOT
  34#else
  35#include <linux/decompress/unlzma.h>
  36#endif /* STATIC */
  37
  38#include <linux/decompress/mm.h>
  39
  40#define MIN(a, b) (((a) < (b)) ? (a) : (b))
  41
  42static long long INIT read_int(unsigned char *ptr, int size)
  43{
  44        int i;
  45        long long ret = 0;
  46
  47        for (i = 0; i < size; i++)
  48                ret = (ret << 8) | ptr[size-i-1];
  49        return ret;
  50}
  51
  52#define ENDIAN_CONVERT(x) \
  53  x = (typeof(x))read_int((unsigned char *)&x, sizeof(x))
  54
  55
  56/* Small range coder implementation for lzma.
  57 *Copyright (C) 2006  Aurelien Jacobs < aurel@gnuage.org >
  58 *
  59 *Based on LzmaDecode.c from the LZMA SDK 4.22 (http://www.7-zip.org/)
  60 *Copyright (c) 1999-2005  Igor Pavlov
  61 */
  62
  63#include <linux/compiler.h>
  64
  65#define LZMA_IOBUF_SIZE 0x10000
  66
  67struct rc {
  68        int (*fill)(void*, unsigned int);
  69        uint8_t *ptr;
  70        uint8_t *buffer;
  71        uint8_t *buffer_end;
  72        int buffer_size;
  73        uint32_t code;
  74        uint32_t range;
  75        uint32_t bound;
  76        void (*error)(char *);
  77};
  78
  79
  80#define RC_TOP_BITS 24
  81#define RC_MOVE_BITS 5
  82#define RC_MODEL_TOTAL_BITS 11
  83
  84
  85static int INIT nofill(void *buffer, unsigned int len)
  86{
  87        return -1;
  88}
  89
  90/* Called twice: once at startup and once in rc_normalize() */
  91static void INIT rc_read(struct rc *rc)
  92{
  93        rc->buffer_size = rc->fill((char *)rc->buffer, LZMA_IOBUF_SIZE);
  94        if (rc->buffer_size <= 0)
  95                rc->error("unexpected EOF");
  96        rc->ptr = rc->buffer;
  97        rc->buffer_end = rc->buffer + rc->buffer_size;
  98}
  99
 100/* Called once */
 101static inline void INIT rc_init(struct rc *rc,
 102                                       int (*fill)(void*, unsigned int),
 103                                       char *buffer, int buffer_size)
 104{
 105        if (fill)
 106                rc->fill = fill;
 107        else
 108                rc->fill = nofill;
 109        rc->buffer = (uint8_t *)buffer;
 110        rc->buffer_size = buffer_size;
 111        rc->buffer_end = rc->buffer + rc->buffer_size;
 112        rc->ptr = rc->buffer;
 113
 114        rc->code = 0;
 115        rc->range = 0xFFFFFFFF;
 116}
 117
 118static inline void INIT rc_init_code(struct rc *rc)
 119{
 120        int i;
 121
 122        for (i = 0; i < 5; i++) {
 123                if (rc->ptr >= rc->buffer_end)
 124                        rc_read(rc);
 125                rc->code = (rc->code << 8) | *rc->ptr++;
 126        }
 127}
 128
 129
 130/* Called twice, but one callsite is in inline'd rc_is_bit_0_helper() */
 131static void INIT rc_do_normalize(struct rc *rc)
 132{
 133        if (rc->ptr >= rc->buffer_end)
 134                rc_read(rc);
 135        rc->range <<= 8;
 136        rc->code = (rc->code << 8) | *rc->ptr++;
 137}
 138static inline void INIT rc_normalize(struct rc *rc)
 139{
 140        if (rc->range < (1 << RC_TOP_BITS))
 141                rc_do_normalize(rc);
 142}
 143
 144/* Called 9 times */
 145/* Why rc_is_bit_0_helper exists?
 146 *Because we want to always expose (rc->code < rc->bound) to optimizer
 147 */
 148static inline uint32_t INIT rc_is_bit_0_helper(struct rc *rc, uint16_t *p)
 149{
 150        rc_normalize(rc);
 151        rc->bound = *p * (rc->range >> RC_MODEL_TOTAL_BITS);
 152        return rc->bound;
 153}
 154static inline int INIT rc_is_bit_0(struct rc *rc, uint16_t *p)
 155{
 156        uint32_t t = rc_is_bit_0_helper(rc, p);
 157        return rc->code < t;
 158}
 159
 160/* Called ~10 times, but very small, thus inlined */
 161static inline void INIT rc_update_bit_0(struct rc *rc, uint16_t *p)
 162{
 163        rc->range = rc->bound;
 164        *p += ((1 << RC_MODEL_TOTAL_BITS) - *p) >> RC_MOVE_BITS;
 165}
 166static inline void INIT rc_update_bit_1(struct rc *rc, uint16_t *p)
 167{
 168        rc->range -= rc->bound;
 169        rc->code -= rc->bound;
 170        *p -= *p >> RC_MOVE_BITS;
 171}
 172
 173/* Called 4 times in unlzma loop */
 174static int INIT rc_get_bit(struct rc *rc, uint16_t *p, int *symbol)
 175{
 176        if (rc_is_bit_0(rc, p)) {
 177                rc_update_bit_0(rc, p);
 178                *symbol *= 2;
 179                return 0;
 180        } else {
 181                rc_update_bit_1(rc, p);
 182                *symbol = *symbol * 2 + 1;
 183                return 1;
 184        }
 185}
 186
 187/* Called once */
 188static inline int INIT rc_direct_bit(struct rc *rc)
 189{
 190        rc_normalize(rc);
 191        rc->range >>= 1;
 192        if (rc->code >= rc->range) {
 193                rc->code -= rc->range;
 194                return 1;
 195        }
 196        return 0;
 197}
 198
 199/* Called twice */
 200static inline void INIT
 201rc_bit_tree_decode(struct rc *rc, uint16_t *p, int num_levels, int *symbol)
 202{
 203        int i = num_levels;
 204
 205        *symbol = 1;
 206        while (i--)
 207                rc_get_bit(rc, p + *symbol, symbol);
 208        *symbol -= 1 << num_levels;
 209}
 210
 211
 212/*
 213 * Small lzma deflate implementation.
 214 * Copyright (C) 2006  Aurelien Jacobs < aurel@gnuage.org >
 215 *
 216 * Based on LzmaDecode.c from the LZMA SDK 4.22 (http://www.7-zip.org/)
 217 * Copyright (C) 1999-2005  Igor Pavlov
 218 */
 219
 220
 221struct lzma_header {
 222        uint8_t pos;
 223        uint32_t dict_size;
 224        uint64_t dst_size;
 225} __attribute__ ((packed)) ;
 226
 227
 228#define LZMA_BASE_SIZE 1846
 229#define LZMA_LIT_SIZE 768
 230
 231#define LZMA_NUM_POS_BITS_MAX 4
 232
 233#define LZMA_LEN_NUM_LOW_BITS 3
 234#define LZMA_LEN_NUM_MID_BITS 3
 235#define LZMA_LEN_NUM_HIGH_BITS 8
 236
 237#define LZMA_LEN_CHOICE 0
 238#define LZMA_LEN_CHOICE_2 (LZMA_LEN_CHOICE + 1)
 239#define LZMA_LEN_LOW (LZMA_LEN_CHOICE_2 + 1)
 240#define LZMA_LEN_MID (LZMA_LEN_LOW \
 241                      + (1 << (LZMA_NUM_POS_BITS_MAX + LZMA_LEN_NUM_LOW_BITS)))
 242#define LZMA_LEN_HIGH (LZMA_LEN_MID \
 243                       +(1 << (LZMA_NUM_POS_BITS_MAX + LZMA_LEN_NUM_MID_BITS)))
 244#define LZMA_NUM_LEN_PROBS (LZMA_LEN_HIGH + (1 << LZMA_LEN_NUM_HIGH_BITS))
 245
 246#define LZMA_NUM_STATES 12
 247#define LZMA_NUM_LIT_STATES 7
 248
 249#define LZMA_START_POS_MODEL_INDEX 4
 250#define LZMA_END_POS_MODEL_INDEX 14
 251#define LZMA_NUM_FULL_DISTANCES (1 << (LZMA_END_POS_MODEL_INDEX >> 1))
 252
 253#define LZMA_NUM_POS_SLOT_BITS 6
 254#define LZMA_NUM_LEN_TO_POS_STATES 4
 255
 256#define LZMA_NUM_ALIGN_BITS 4
 257
 258#define LZMA_MATCH_MIN_LEN 2
 259
 260#define LZMA_IS_MATCH 0
 261#define LZMA_IS_REP (LZMA_IS_MATCH + (LZMA_NUM_STATES << LZMA_NUM_POS_BITS_MAX))
 262#define LZMA_IS_REP_G0 (LZMA_IS_REP + LZMA_NUM_STATES)
 263#define LZMA_IS_REP_G1 (LZMA_IS_REP_G0 + LZMA_NUM_STATES)
 264#define LZMA_IS_REP_G2 (LZMA_IS_REP_G1 + LZMA_NUM_STATES)
 265#define LZMA_IS_REP_0_LONG (LZMA_IS_REP_G2 + LZMA_NUM_STATES)
 266#define LZMA_POS_SLOT (LZMA_IS_REP_0_LONG \
 267                       + (LZMA_NUM_STATES << LZMA_NUM_POS_BITS_MAX))
 268#define LZMA_SPEC_POS (LZMA_POS_SLOT \
 269                       +(LZMA_NUM_LEN_TO_POS_STATES << LZMA_NUM_POS_SLOT_BITS))
 270#define LZMA_ALIGN (LZMA_SPEC_POS \
 271                    + LZMA_NUM_FULL_DISTANCES - LZMA_END_POS_MODEL_INDEX)
 272#define LZMA_LEN_CODER (LZMA_ALIGN + (1 << LZMA_NUM_ALIGN_BITS))
 273#define LZMA_REP_LEN_CODER (LZMA_LEN_CODER + LZMA_NUM_LEN_PROBS)
 274#define LZMA_LITERAL (LZMA_REP_LEN_CODER + LZMA_NUM_LEN_PROBS)
 275
 276
 277struct writer {
 278        uint8_t *buffer;
 279        uint8_t previous_byte;
 280        size_t buffer_pos;
 281        int bufsize;
 282        size_t global_pos;
 283        int(*flush)(void*, unsigned int);
 284        struct lzma_header *header;
 285};
 286
 287struct cstate {
 288        int state;
 289        uint32_t rep0, rep1, rep2, rep3;
 290};
 291
 292static inline size_t INIT get_pos(struct writer *wr)
 293{
 294        return
 295                wr->global_pos + wr->buffer_pos;
 296}
 297
 298static inline uint8_t INIT peek_old_byte(struct writer *wr,
 299                                                uint32_t offs)
 300{
 301        if (!wr->flush) {
 302                int32_t pos;
 303                while (offs > wr->header->dict_size)
 304                        offs -= wr->header->dict_size;
 305                pos = wr->buffer_pos - offs;
 306                return wr->buffer[pos];
 307        } else {
 308                uint32_t pos = wr->buffer_pos - offs;
 309                while (pos >= wr->header->dict_size)
 310                        pos += wr->header->dict_size;
 311                return wr->buffer[pos];
 312        }
 313
 314}
 315
 316static inline int INIT write_byte(struct writer *wr, uint8_t byte)
 317{
 318        wr->buffer[wr->buffer_pos++] = wr->previous_byte = byte;
 319        if (wr->flush && wr->buffer_pos == wr->header->dict_size) {
 320                wr->buffer_pos = 0;
 321                wr->global_pos += wr->header->dict_size;
 322                if (wr->flush((char *)wr->buffer, wr->header->dict_size)
 323                                != wr->header->dict_size)
 324                        return -1;
 325        }
 326        return 0;
 327}
 328
 329
 330static inline int INIT copy_byte(struct writer *wr, uint32_t offs)
 331{
 332        return write_byte(wr, peek_old_byte(wr, offs));
 333}
 334
 335static inline int INIT copy_bytes(struct writer *wr,
 336                                         uint32_t rep0, int len)
 337{
 338        do {
 339                if (copy_byte(wr, rep0))
 340                        return -1;
 341                len--;
 342        } while (len != 0 && wr->buffer_pos < wr->header->dst_size);
 343
 344        return len;
 345}
 346
 347static inline int INIT process_bit0(struct writer *wr, struct rc *rc,
 348                                     struct cstate *cst, uint16_t *p,
 349                                     int pos_state, uint16_t *prob,
 350                                     int lc, uint32_t literal_pos_mask) {
 351        int mi = 1;
 352        rc_update_bit_0(rc, prob);
 353        prob = (p + LZMA_LITERAL +
 354                (LZMA_LIT_SIZE
 355                 * (((get_pos(wr) & literal_pos_mask) << lc)
 356                    + (wr->previous_byte >> (8 - lc))))
 357                );
 358
 359        if (cst->state >= LZMA_NUM_LIT_STATES) {
 360                int match_byte = peek_old_byte(wr, cst->rep0);
 361                do {
 362                        int bit;
 363                        uint16_t *prob_lit;
 364
 365                        match_byte <<= 1;
 366                        bit = match_byte & 0x100;
 367                        prob_lit = prob + 0x100 + bit + mi;
 368                        if (rc_get_bit(rc, prob_lit, &mi)) {
 369                                if (!bit)
 370                                        break;
 371                        } else {
 372                                if (bit)
 373                                        break;
 374                        }
 375                } while (mi < 0x100);
 376        }
 377        while (mi < 0x100) {
 378                uint16_t *prob_lit = prob + mi;
 379                rc_get_bit(rc, prob_lit, &mi);
 380        }
 381        if (cst->state < 4)
 382                cst->state = 0;
 383        else if (cst->state < 10)
 384                cst->state -= 3;
 385        else
 386                cst->state -= 6;
 387
 388        return write_byte(wr, mi);
 389}
 390
 391static inline int INIT process_bit1(struct writer *wr, struct rc *rc,
 392                                            struct cstate *cst, uint16_t *p,
 393                                            int pos_state, uint16_t *prob) {
 394  int offset;
 395        uint16_t *prob_len;
 396        int num_bits;
 397        int len;
 398
 399        rc_update_bit_1(rc, prob);
 400        prob = p + LZMA_IS_REP + cst->state;
 401        if (rc_is_bit_0(rc, prob)) {
 402                rc_update_bit_0(rc, prob);
 403                cst->rep3 = cst->rep2;
 404                cst->rep2 = cst->rep1;
 405                cst->rep1 = cst->rep0;
 406                cst->state = cst->state < LZMA_NUM_LIT_STATES ? 0 : 3;
 407                prob = p + LZMA_LEN_CODER;
 408        } else {
 409                rc_update_bit_1(rc, prob);
 410                prob = p + LZMA_IS_REP_G0 + cst->state;
 411                if (rc_is_bit_0(rc, prob)) {
 412                        rc_update_bit_0(rc, prob);
 413                        prob = (p + LZMA_IS_REP_0_LONG
 414                                + (cst->state <<
 415                                   LZMA_NUM_POS_BITS_MAX) +
 416                                pos_state);
 417                        if (rc_is_bit_0(rc, prob)) {
 418                                rc_update_bit_0(rc, prob);
 419
 420                                cst->state = cst->state < LZMA_NUM_LIT_STATES ?
 421                                        9 : 11;
 422                                return copy_byte(wr, cst->rep0);
 423                        } else {
 424                                rc_update_bit_1(rc, prob);
 425                        }
 426                } else {
 427                        uint32_t distance;
 428
 429                        rc_update_bit_1(rc, prob);
 430                        prob = p + LZMA_IS_REP_G1 + cst->state;
 431                        if (rc_is_bit_0(rc, prob)) {
 432                                rc_update_bit_0(rc, prob);
 433                                distance = cst->rep1;
 434                        } else {
 435                                rc_update_bit_1(rc, prob);
 436                                prob = p + LZMA_IS_REP_G2 + cst->state;
 437                                if (rc_is_bit_0(rc, prob)) {
 438                                        rc_update_bit_0(rc, prob);
 439                                        distance = cst->rep2;
 440                                } else {
 441                                        rc_update_bit_1(rc, prob);
 442                                        distance = cst->rep3;
 443                                        cst->rep3 = cst->rep2;
 444                                }
 445                                cst->rep2 = cst->rep1;
 446                        }
 447                        cst->rep1 = cst->rep0;
 448                        cst->rep0 = distance;
 449                }
 450                cst->state = cst->state < LZMA_NUM_LIT_STATES ? 8 : 11;
 451                prob = p + LZMA_REP_LEN_CODER;
 452        }
 453
 454        prob_len = prob + LZMA_LEN_CHOICE;
 455        if (rc_is_bit_0(rc, prob_len)) {
 456                rc_update_bit_0(rc, prob_len);
 457                prob_len = (prob + LZMA_LEN_LOW
 458                            + (pos_state <<
 459                               LZMA_LEN_NUM_LOW_BITS));
 460                offset = 0;
 461                num_bits = LZMA_LEN_NUM_LOW_BITS;
 462        } else {
 463                rc_update_bit_1(rc, prob_len);
 464                prob_len = prob + LZMA_LEN_CHOICE_2;
 465                if (rc_is_bit_0(rc, prob_len)) {
 466                        rc_update_bit_0(rc, prob_len);
 467                        prob_len = (prob + LZMA_LEN_MID
 468                                    + (pos_state <<
 469                                       LZMA_LEN_NUM_MID_BITS));
 470                        offset = 1 << LZMA_LEN_NUM_LOW_BITS;
 471                        num_bits = LZMA_LEN_NUM_MID_BITS;
 472                } else {
 473                        rc_update_bit_1(rc, prob_len);
 474                        prob_len = prob + LZMA_LEN_HIGH;
 475                        offset = ((1 << LZMA_LEN_NUM_LOW_BITS)
 476                                  + (1 << LZMA_LEN_NUM_MID_BITS));
 477                        num_bits = LZMA_LEN_NUM_HIGH_BITS;
 478                }
 479        }
 480
 481        rc_bit_tree_decode(rc, prob_len, num_bits, &len);
 482        len += offset;
 483
 484        if (cst->state < 4) {
 485                int pos_slot;
 486
 487                cst->state += LZMA_NUM_LIT_STATES;
 488                prob =
 489                        p + LZMA_POS_SLOT +
 490                        ((len <
 491                          LZMA_NUM_LEN_TO_POS_STATES ? len :
 492                          LZMA_NUM_LEN_TO_POS_STATES - 1)
 493                         << LZMA_NUM_POS_SLOT_BITS);
 494                rc_bit_tree_decode(rc, prob,
 495                                   LZMA_NUM_POS_SLOT_BITS,
 496                                   &pos_slot);
 497                if (pos_slot >= LZMA_START_POS_MODEL_INDEX) {
 498                        int i, mi;
 499                        num_bits = (pos_slot >> 1) - 1;
 500                        cst->rep0 = 2 | (pos_slot & 1);
 501                        if (pos_slot < LZMA_END_POS_MODEL_INDEX) {
 502                                cst->rep0 <<= num_bits;
 503                                prob = p + LZMA_SPEC_POS +
 504                                        cst->rep0 - pos_slot - 1;
 505                        } else {
 506                                num_bits -= LZMA_NUM_ALIGN_BITS;
 507                                while (num_bits--)
 508                                        cst->rep0 = (cst->rep0 << 1) |
 509                                                rc_direct_bit(rc);
 510                                prob = p + LZMA_ALIGN;
 511                                cst->rep0 <<= LZMA_NUM_ALIGN_BITS;
 512                                num_bits = LZMA_NUM_ALIGN_BITS;
 513                        }
 514                        i = 1;
 515                        mi = 1;
 516                        while (num_bits--) {
 517                                if (rc_get_bit(rc, prob + mi, &mi))
 518                                        cst->rep0 |= i;
 519                                i <<= 1;
 520                        }
 521                } else
 522                        cst->rep0 = pos_slot;
 523                if (++(cst->rep0) == 0)
 524                        return 0;
 525                if (cst->rep0 > wr->header->dict_size
 526                                || cst->rep0 > get_pos(wr))
 527                        return -1;
 528        }
 529
 530        len += LZMA_MATCH_MIN_LEN;
 531
 532        return copy_bytes(wr, cst->rep0, len);
 533}
 534
 535
 536
 537STATIC inline int INIT unlzma(unsigned char *buf, int in_len,
 538                              int(*fill)(void*, unsigned int),
 539                              int(*flush)(void*, unsigned int),
 540                              unsigned char *output,
 541                              int *posp,
 542                              void(*error)(char *x)
 543        )
 544{
 545        struct lzma_header header;
 546        int lc, pb, lp;
 547        uint32_t pos_state_mask;
 548        uint32_t literal_pos_mask;
 549        uint16_t *p;
 550        int num_probs;
 551        struct rc rc;
 552        int i, mi;
 553        struct writer wr;
 554        struct cstate cst;
 555        unsigned char *inbuf;
 556        int ret = -1;
 557
 558        rc.error = error;
 559
 560        if (buf)
 561                inbuf = buf;
 562        else
 563                inbuf = malloc(LZMA_IOBUF_SIZE);
 564        if (!inbuf) {
 565                error("Could not allocate input buffer");
 566                goto exit_0;
 567        }
 568
 569        cst.state = 0;
 570        cst.rep0 = cst.rep1 = cst.rep2 = cst.rep3 = 1;
 571
 572        wr.header = &header;
 573        wr.flush = flush;
 574        wr.global_pos = 0;
 575        wr.previous_byte = 0;
 576        wr.buffer_pos = 0;
 577
 578        rc_init(&rc, fill, inbuf, in_len);
 579
 580        for (i = 0; i < sizeof(header); i++) {
 581                if (rc.ptr >= rc.buffer_end)
 582                        rc_read(&rc);
 583                ((unsigned char *)&header)[i] = *rc.ptr++;
 584        }
 585
 586        if (header.pos >= (9 * 5 * 5)) {
 587                error("bad header");
 588                goto exit_1;
 589        }
 590
 591        mi = 0;
 592        lc = header.pos;
 593        while (lc >= 9) {
 594                mi++;
 595                lc -= 9;
 596        }
 597        pb = 0;
 598        lp = mi;
 599        while (lp >= 5) {
 600                pb++;
 601                lp -= 5;
 602        }
 603        pos_state_mask = (1 << pb) - 1;
 604        literal_pos_mask = (1 << lp) - 1;
 605
 606        ENDIAN_CONVERT(header.dict_size);
 607        ENDIAN_CONVERT(header.dst_size);
 608
 609        if (header.dict_size == 0)
 610                header.dict_size = 1;
 611
 612        if (output)
 613                wr.buffer = output;
 614        else {
 615                wr.bufsize = MIN(header.dst_size, header.dict_size);
 616                wr.buffer = large_malloc(wr.bufsize);
 617        }
 618        if (wr.buffer == NULL)
 619                goto exit_1;
 620
 621        num_probs = LZMA_BASE_SIZE + (LZMA_LIT_SIZE << (lc + lp));
 622        p = (uint16_t *) large_malloc(num_probs * sizeof(*p));
 623        if (p == 0)
 624                goto exit_2;
 625        num_probs = LZMA_LITERAL + (LZMA_LIT_SIZE << (lc + lp));
 626        for (i = 0; i < num_probs; i++)
 627                p[i] = (1 << RC_MODEL_TOTAL_BITS) >> 1;
 628
 629        rc_init_code(&rc);
 630
 631        while (get_pos(&wr) < header.dst_size) {
 632                int pos_state = get_pos(&wr) & pos_state_mask;
 633                uint16_t *prob = p + LZMA_IS_MATCH +
 634                        (cst.state << LZMA_NUM_POS_BITS_MAX) + pos_state;
 635                if (rc_is_bit_0(&rc, prob)) {
 636                        if (process_bit0(&wr, &rc, &cst, p, pos_state, prob,
 637                                        lc, literal_pos_mask)) {
 638                                error("LZMA data is corrupt");
 639                                goto exit_3;
 640                        }
 641                } else {
 642                        if (process_bit1(&wr, &rc, &cst, p, pos_state, prob)) {
 643                                error("LZMA data is corrupt");
 644                                goto exit_3;
 645                        }
 646                        if (cst.rep0 == 0)
 647                                break;
 648                }
 649                if (rc.buffer_size <= 0)
 650                        goto exit_3;
 651        }
 652
 653        if (posp)
 654                *posp = rc.ptr-rc.buffer;
 655        if (!wr.flush || wr.flush(wr.buffer, wr.buffer_pos) == wr.buffer_pos)
 656                ret = 0;
 657exit_3:
 658        large_free(p);
 659exit_2:
 660        if (!output)
 661                large_free(wr.buffer);
 662exit_1:
 663        if (!buf)
 664                free(inbuf);
 665exit_0:
 666        return ret;
 667}
 668
 669#ifdef PREBOOT
 670STATIC int INIT decompress(unsigned char *buf, int in_len,
 671                              int(*fill)(void*, unsigned int),
 672                              int(*flush)(void*, unsigned int),
 673                              unsigned char *output,
 674                              int *posp,
 675                              void(*error)(char *x)
 676        )
 677{
 678        return unlzma(buf, in_len - 4, fill, flush, output, posp, error);
 679}
 680#endif
 681
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