001 /* 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, 013 * software distributed under the License is distributed on an 014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 015 * KIND, either express or implied. See the License for the 016 * specific language governing permissions and limitations 017 * under the License. 018 */ 019 020 /* 021 * This package is based on the work done by Keiron Liddle, Aftex Software 022 * <keiron@aftexsw.com> to whom the Ant project is very grateful for his 023 * great code. 024 */ 025 package org.apache.commons.compress.compressors.bzip2; 026 027 import java.io.IOException; 028 import java.io.InputStream; 029 030 import org.apache.commons.compress.compressors.CompressorInputStream; 031 032 /** 033 * An input stream that decompresses from the BZip2 format to be read as any other stream. 034 * 035 * @NotThreadSafe 036 */ 037 public class BZip2CompressorInputStream extends CompressorInputStream implements 038 BZip2Constants { 039 040 /** 041 * Index of the last char in the block, so the block size == last + 1. 042 */ 043 private int last; 044 045 /** 046 * Index in zptr[] of original string after sorting. 047 */ 048 private int origPtr; 049 050 /** 051 * always: in the range 0 .. 9. The current block size is 100000 * this 052 * number. 053 */ 054 private int blockSize100k; 055 056 private boolean blockRandomised; 057 058 private int bsBuff; 059 private int bsLive; 060 private final CRC crc = new CRC(); 061 062 private int nInUse; 063 064 private InputStream in; 065 066 private int currentChar = -1; 067 068 private static final int EOF = 0; 069 private static final int START_BLOCK_STATE = 1; 070 private static final int RAND_PART_A_STATE = 2; 071 private static final int RAND_PART_B_STATE = 3; 072 private static final int RAND_PART_C_STATE = 4; 073 private static final int NO_RAND_PART_A_STATE = 5; 074 private static final int NO_RAND_PART_B_STATE = 6; 075 private static final int NO_RAND_PART_C_STATE = 7; 076 077 private int currentState = START_BLOCK_STATE; 078 079 private int storedBlockCRC, storedCombinedCRC; 080 private int computedBlockCRC, computedCombinedCRC; 081 082 // Variables used by setup* methods exclusively 083 084 private int su_count; 085 private int su_ch2; 086 private int su_chPrev; 087 private int su_i2; 088 private int su_j2; 089 private int su_rNToGo; 090 private int su_rTPos; 091 private int su_tPos; 092 private char su_z; 093 094 /** 095 * All memory intensive stuff. This field is initialized by initBlock(). 096 */ 097 private BZip2CompressorInputStream.Data data; 098 099 /** 100 * Constructs a new BZip2CompressorInputStream which decompresses bytes read from the 101 * specified stream. 102 * 103 * @throws IOException 104 * if the stream content is malformed or an I/O error occurs. 105 * @throws NullPointerException 106 * if <tt>in == null</tt> 107 */ 108 public BZip2CompressorInputStream(final InputStream in) throws IOException { 109 super(); 110 111 this.in = in; 112 init(); 113 } 114 115 /* 116 * (non-Javadoc) 117 * 118 * @see java.io.InputStream#read() 119 */ 120 public int read() throws IOException { 121 if (this.in != null) { 122 return read0(); 123 } else { 124 throw new IOException("stream closed"); 125 } 126 } 127 128 /* 129 * (non-Javadoc) 130 * 131 * @see java.io.InputStream#read(byte[], int, int) 132 */ 133 public int read(final byte[] dest, final int offs, final int len) 134 throws IOException { 135 if (offs < 0) { 136 throw new IndexOutOfBoundsException("offs(" + offs + ") < 0."); 137 } 138 if (len < 0) { 139 throw new IndexOutOfBoundsException("len(" + len + ") < 0."); 140 } 141 if (offs + len > dest.length) { 142 throw new IndexOutOfBoundsException("offs(" + offs + ") + len(" 143 + len + ") > dest.length(" + dest.length + ")."); 144 } 145 if (this.in == null) { 146 throw new IOException("stream closed"); 147 } 148 149 final int hi = offs + len; 150 int destOffs = offs; 151 for (int b; (destOffs < hi) && ((b = read0()) >= 0);) { 152 dest[destOffs++] = (byte) b; 153 } 154 155 return (destOffs == offs) ? -1 : (destOffs - offs); 156 } 157 158 private void makeMaps() { 159 final boolean[] inUse = this.data.inUse; 160 final byte[] seqToUnseq = this.data.seqToUnseq; 161 162 int nInUseShadow = 0; 163 164 for (int i = 0; i < 256; i++) { 165 if (inUse[i]) 166 seqToUnseq[nInUseShadow++] = (byte) i; 167 } 168 169 this.nInUse = nInUseShadow; 170 } 171 172 private int read0() throws IOException { 173 final int retChar = this.currentChar; 174 175 switch (this.currentState) { 176 case EOF: 177 return -1; 178 179 case START_BLOCK_STATE: 180 throw new IllegalStateException(); 181 182 case RAND_PART_A_STATE: 183 throw new IllegalStateException(); 184 185 case RAND_PART_B_STATE: 186 setupRandPartB(); 187 break; 188 189 case RAND_PART_C_STATE: 190 setupRandPartC(); 191 break; 192 193 case NO_RAND_PART_A_STATE: 194 throw new IllegalStateException(); 195 196 case NO_RAND_PART_B_STATE: 197 setupNoRandPartB(); 198 break; 199 200 case NO_RAND_PART_C_STATE: 201 setupNoRandPartC(); 202 break; 203 204 default: 205 throw new IllegalStateException(); 206 } 207 208 return retChar; 209 } 210 211 private void init() throws IOException { 212 if (null == in) { 213 throw new IOException("No InputStream"); 214 } 215 if (in.available() == 0) { 216 throw new IOException("Empty InputStream"); 217 } 218 checkMagicChar('B', "first"); 219 checkMagicChar('Z', "second"); 220 checkMagicChar('h', "third"); 221 222 int blockSize = this.in.read(); 223 if ((blockSize < '1') || (blockSize > '9')) { 224 throw new IOException("Stream is not BZip2 formatted: illegal " 225 + "blocksize " + (char) blockSize); 226 } 227 228 this.blockSize100k = blockSize - '0'; 229 230 initBlock(); 231 setupBlock(); 232 } 233 234 private void checkMagicChar(char expected, String position) 235 throws IOException { 236 int magic = this.in.read(); 237 if (magic != expected) { 238 throw new IOException("Stream is not BZip2 formatted: expected '" 239 + expected + "' as " + position + " byte but got '" 240 + (char) magic + "'"); 241 } 242 } 243 244 private void initBlock() throws IOException { 245 char magic0 = bsGetUByte(); 246 char magic1 = bsGetUByte(); 247 char magic2 = bsGetUByte(); 248 char magic3 = bsGetUByte(); 249 char magic4 = bsGetUByte(); 250 char magic5 = bsGetUByte(); 251 252 if (magic0 == 0x17 && magic1 == 0x72 && magic2 == 0x45 253 && magic3 == 0x38 && magic4 == 0x50 && magic5 == 0x90) { 254 complete(); // end of file 255 } else if (magic0 != 0x31 || // '1' 256 magic1 != 0x41 || // ')' 257 magic2 != 0x59 || // 'Y' 258 magic3 != 0x26 || // '&' 259 magic4 != 0x53 || // 'S' 260 magic5 != 0x59 // 'Y' 261 ) { 262 this.currentState = EOF; 263 throw new IOException("bad block header"); 264 } else { 265 this.storedBlockCRC = bsGetInt(); 266 this.blockRandomised = bsR(1) == 1; 267 268 /** 269 * Allocate data here instead in constructor, so we do not allocate 270 * it if the input file is empty. 271 */ 272 if (this.data == null) { 273 this.data = new Data(this.blockSize100k); 274 } 275 276 // currBlockNo++; 277 getAndMoveToFrontDecode(); 278 279 this.crc.initialiseCRC(); 280 this.currentState = START_BLOCK_STATE; 281 } 282 } 283 284 private void endBlock() throws IOException { 285 this.computedBlockCRC = this.crc.getFinalCRC(); 286 287 // A bad CRC is considered a fatal error. 288 if (this.storedBlockCRC != this.computedBlockCRC) { 289 // make next blocks readable without error 290 // (repair feature, not yet documented, not tested) 291 this.computedCombinedCRC = (this.storedCombinedCRC << 1) 292 | (this.storedCombinedCRC >>> 31); 293 this.computedCombinedCRC ^= this.storedBlockCRC; 294 295 throw new IOException("BZip2 CRC error"); 296 } 297 298 this.computedCombinedCRC = (this.computedCombinedCRC << 1) 299 | (this.computedCombinedCRC >>> 31); 300 this.computedCombinedCRC ^= this.computedBlockCRC; 301 } 302 303 private void complete() throws IOException { 304 this.storedCombinedCRC = bsGetInt(); 305 this.currentState = EOF; 306 this.data = null; 307 308 if (this.storedCombinedCRC != this.computedCombinedCRC) { 309 throw new IOException("BZip2 CRC error"); 310 } 311 } 312 313 public void close() throws IOException { 314 InputStream inShadow = this.in; 315 if (inShadow != null) { 316 try { 317 if (inShadow != System.in) { 318 inShadow.close(); 319 } 320 } finally { 321 this.data = null; 322 this.in = null; 323 } 324 } 325 } 326 327 private int bsR(final int n) throws IOException { 328 int bsLiveShadow = this.bsLive; 329 int bsBuffShadow = this.bsBuff; 330 331 if (bsLiveShadow < n) { 332 final InputStream inShadow = this.in; 333 do { 334 int thech = inShadow.read(); 335 336 if (thech < 0) { 337 throw new IOException("unexpected end of stream"); 338 } 339 340 bsBuffShadow = (bsBuffShadow << 8) | thech; 341 bsLiveShadow += 8; 342 } while (bsLiveShadow < n); 343 344 this.bsBuff = bsBuffShadow; 345 } 346 347 this.bsLive = bsLiveShadow - n; 348 return (bsBuffShadow >> (bsLiveShadow - n)) & ((1 << n) - 1); 349 } 350 351 private boolean bsGetBit() throws IOException { 352 int bsLiveShadow = this.bsLive; 353 int bsBuffShadow = this.bsBuff; 354 355 if (bsLiveShadow < 1) { 356 int thech = this.in.read(); 357 358 if (thech < 0) { 359 throw new IOException("unexpected end of stream"); 360 } 361 362 bsBuffShadow = (bsBuffShadow << 8) | thech; 363 bsLiveShadow += 8; 364 this.bsBuff = bsBuffShadow; 365 } 366 367 this.bsLive = bsLiveShadow - 1; 368 return ((bsBuffShadow >> (bsLiveShadow - 1)) & 1) != 0; 369 } 370 371 private char bsGetUByte() throws IOException { 372 return (char) bsR(8); 373 } 374 375 private int bsGetInt() throws IOException { 376 return (((((bsR(8) << 8) | bsR(8)) << 8) | bsR(8)) << 8) | bsR(8); 377 } 378 379 /** 380 * Called by createHuffmanDecodingTables() exclusively. 381 */ 382 private static void hbCreateDecodeTables(final int[] limit, 383 final int[] base, final int[] perm, final char[] length, 384 final int minLen, final int maxLen, final int alphaSize) { 385 for (int i = minLen, pp = 0; i <= maxLen; i++) { 386 for (int j = 0; j < alphaSize; j++) { 387 if (length[j] == i) { 388 perm[pp++] = j; 389 } 390 } 391 } 392 393 for (int i = MAX_CODE_LEN; --i > 0;) { 394 base[i] = 0; 395 limit[i] = 0; 396 } 397 398 for (int i = 0; i < alphaSize; i++) { 399 base[length[i] + 1]++; 400 } 401 402 for (int i = 1, b = base[0]; i < MAX_CODE_LEN; i++) { 403 b += base[i]; 404 base[i] = b; 405 } 406 407 for (int i = minLen, vec = 0, b = base[i]; i <= maxLen; i++) { 408 final int nb = base[i + 1]; 409 vec += nb - b; 410 b = nb; 411 limit[i] = vec - 1; 412 vec <<= 1; 413 } 414 415 for (int i = minLen + 1; i <= maxLen; i++) { 416 base[i] = ((limit[i - 1] + 1) << 1) - base[i]; 417 } 418 } 419 420 private void recvDecodingTables() throws IOException { 421 final Data dataShadow = this.data; 422 final boolean[] inUse = dataShadow.inUse; 423 final byte[] pos = dataShadow.recvDecodingTables_pos; 424 final byte[] selector = dataShadow.selector; 425 final byte[] selectorMtf = dataShadow.selectorMtf; 426 427 int inUse16 = 0; 428 429 /* Receive the mapping table */ 430 for (int i = 0; i < 16; i++) { 431 if (bsGetBit()) { 432 inUse16 |= 1 << i; 433 } 434 } 435 436 for (int i = 256; --i >= 0;) { 437 inUse[i] = false; 438 } 439 440 for (int i = 0; i < 16; i++) { 441 if ((inUse16 & (1 << i)) != 0) { 442 final int i16 = i << 4; 443 for (int j = 0; j < 16; j++) { 444 if (bsGetBit()) { 445 inUse[i16 + j] = true; 446 } 447 } 448 } 449 } 450 451 makeMaps(); 452 final int alphaSize = this.nInUse + 2; 453 454 /* Now the selectors */ 455 final int nGroups = bsR(3); 456 final int nSelectors = bsR(15); 457 458 for (int i = 0; i < nSelectors; i++) { 459 int j = 0; 460 while (bsGetBit()) { 461 j++; 462 } 463 selectorMtf[i] = (byte) j; 464 } 465 466 /* Undo the MTF values for the selectors. */ 467 for (int v = nGroups; --v >= 0;) { 468 pos[v] = (byte) v; 469 } 470 471 for (int i = 0; i < nSelectors; i++) { 472 int v = selectorMtf[i] & 0xff; 473 final byte tmp = pos[v]; 474 while (v > 0) { 475 // nearly all times v is zero, 4 in most other cases 476 pos[v] = pos[v - 1]; 477 v--; 478 } 479 pos[0] = tmp; 480 selector[i] = tmp; 481 } 482 483 final char[][] len = dataShadow.temp_charArray2d; 484 485 /* Now the coding tables */ 486 for (int t = 0; t < nGroups; t++) { 487 int curr = bsR(5); 488 final char[] len_t = len[t]; 489 for (int i = 0; i < alphaSize; i++) { 490 while (bsGetBit()) { 491 curr += bsGetBit() ? -1 : 1; 492 } 493 len_t[i] = (char) curr; 494 } 495 } 496 497 // finally create the Huffman tables 498 createHuffmanDecodingTables(alphaSize, nGroups); 499 } 500 501 /** 502 * Called by recvDecodingTables() exclusively. 503 */ 504 private void createHuffmanDecodingTables(final int alphaSize, 505 final int nGroups) { 506 final Data dataShadow = this.data; 507 final char[][] len = dataShadow.temp_charArray2d; 508 final int[] minLens = dataShadow.minLens; 509 final int[][] limit = dataShadow.limit; 510 final int[][] base = dataShadow.base; 511 final int[][] perm = dataShadow.perm; 512 513 for (int t = 0; t < nGroups; t++) { 514 int minLen = 32; 515 int maxLen = 0; 516 final char[] len_t = len[t]; 517 for (int i = alphaSize; --i >= 0;) { 518 final char lent = len_t[i]; 519 if (lent > maxLen) { 520 maxLen = lent; 521 } 522 if (lent < minLen) { 523 minLen = lent; 524 } 525 } 526 hbCreateDecodeTables(limit[t], base[t], perm[t], len[t], minLen, 527 maxLen, alphaSize); 528 minLens[t] = minLen; 529 } 530 } 531 532 private void getAndMoveToFrontDecode() throws IOException { 533 this.origPtr = bsR(24); 534 recvDecodingTables(); 535 536 final InputStream inShadow = this.in; 537 final Data dataShadow = this.data; 538 final byte[] ll8 = dataShadow.ll8; 539 final int[] unzftab = dataShadow.unzftab; 540 final byte[] selector = dataShadow.selector; 541 final byte[] seqToUnseq = dataShadow.seqToUnseq; 542 final char[] yy = dataShadow.getAndMoveToFrontDecode_yy; 543 final int[] minLens = dataShadow.minLens; 544 final int[][] limit = dataShadow.limit; 545 final int[][] base = dataShadow.base; 546 final int[][] perm = dataShadow.perm; 547 final int limitLast = this.blockSize100k * 100000; 548 549 /* 550 * Setting up the unzftab entries here is not strictly necessary, but it 551 * does save having to do it later in a separate pass, and so saves a 552 * block's worth of cache misses. 553 */ 554 for (int i = 256; --i >= 0;) { 555 yy[i] = (char) i; 556 unzftab[i] = 0; 557 } 558 559 int groupNo = 0; 560 int groupPos = G_SIZE - 1; 561 final int eob = this.nInUse + 1; 562 int nextSym = getAndMoveToFrontDecode0(0); 563 int bsBuffShadow = this.bsBuff; 564 int bsLiveShadow = this.bsLive; 565 int lastShadow = -1; 566 int zt = selector[groupNo] & 0xff; 567 int[] base_zt = base[zt]; 568 int[] limit_zt = limit[zt]; 569 int[] perm_zt = perm[zt]; 570 int minLens_zt = minLens[zt]; 571 572 while (nextSym != eob) { 573 if ((nextSym == RUNA) || (nextSym == RUNB)) { 574 int s = -1; 575 576 for (int n = 1; true; n <<= 1) { 577 if (nextSym == RUNA) { 578 s += n; 579 } else if (nextSym == RUNB) { 580 s += n << 1; 581 } else { 582 break; 583 } 584 585 if (groupPos == 0) { 586 groupPos = G_SIZE - 1; 587 zt = selector[++groupNo] & 0xff; 588 base_zt = base[zt]; 589 limit_zt = limit[zt]; 590 perm_zt = perm[zt]; 591 minLens_zt = minLens[zt]; 592 } else { 593 groupPos--; 594 } 595 596 int zn = minLens_zt; 597 598 // Inlined: 599 // int zvec = bsR(zn); 600 while (bsLiveShadow < zn) { 601 final int thech = inShadow.read(); 602 if (thech >= 0) { 603 bsBuffShadow = (bsBuffShadow << 8) | thech; 604 bsLiveShadow += 8; 605 continue; 606 } else { 607 throw new IOException("unexpected end of stream"); 608 } 609 } 610 int zvec = (bsBuffShadow >> (bsLiveShadow - zn)) 611 & ((1 << zn) - 1); 612 bsLiveShadow -= zn; 613 614 while (zvec > limit_zt[zn]) { 615 zn++; 616 while (bsLiveShadow < 1) { 617 final int thech = inShadow.read(); 618 if (thech >= 0) { 619 bsBuffShadow = (bsBuffShadow << 8) | thech; 620 bsLiveShadow += 8; 621 continue; 622 } else { 623 throw new IOException( 624 "unexpected end of stream"); 625 } 626 } 627 bsLiveShadow--; 628 zvec = (zvec << 1) 629 | ((bsBuffShadow >> bsLiveShadow) & 1); 630 } 631 nextSym = perm_zt[zvec - base_zt[zn]]; 632 } 633 634 final byte ch = seqToUnseq[yy[0]]; 635 unzftab[ch & 0xff] += s + 1; 636 637 while (s-- >= 0) { 638 ll8[++lastShadow] = ch; 639 } 640 641 if (lastShadow >= limitLast) { 642 throw new IOException("block overrun"); 643 } 644 } else { 645 if (++lastShadow >= limitLast) { 646 throw new IOException("block overrun"); 647 } 648 649 final char tmp = yy[nextSym - 1]; 650 unzftab[seqToUnseq[tmp] & 0xff]++; 651 ll8[lastShadow] = seqToUnseq[tmp]; 652 653 /* 654 * This loop is hammered during decompression, hence avoid 655 * native method call overhead of System.arraycopy for very 656 * small ranges to copy. 657 */ 658 if (nextSym <= 16) { 659 for (int j = nextSym - 1; j > 0;) { 660 yy[j] = yy[--j]; 661 } 662 } else { 663 System.arraycopy(yy, 0, yy, 1, nextSym - 1); 664 } 665 666 yy[0] = tmp; 667 668 if (groupPos == 0) { 669 groupPos = G_SIZE - 1; 670 zt = selector[++groupNo] & 0xff; 671 base_zt = base[zt]; 672 limit_zt = limit[zt]; 673 perm_zt = perm[zt]; 674 minLens_zt = minLens[zt]; 675 } else { 676 groupPos--; 677 } 678 679 int zn = minLens_zt; 680 681 // Inlined: 682 // int zvec = bsR(zn); 683 while (bsLiveShadow < zn) { 684 final int thech = inShadow.read(); 685 if (thech >= 0) { 686 bsBuffShadow = (bsBuffShadow << 8) | thech; 687 bsLiveShadow += 8; 688 continue; 689 } else { 690 throw new IOException("unexpected end of stream"); 691 } 692 } 693 int zvec = (bsBuffShadow >> (bsLiveShadow - zn)) 694 & ((1 << zn) - 1); 695 bsLiveShadow -= zn; 696 697 while (zvec > limit_zt[zn]) { 698 zn++; 699 while (bsLiveShadow < 1) { 700 final int thech = inShadow.read(); 701 if (thech >= 0) { 702 bsBuffShadow = (bsBuffShadow << 8) | thech; 703 bsLiveShadow += 8; 704 continue; 705 } else { 706 throw new IOException("unexpected end of stream"); 707 } 708 } 709 bsLiveShadow--; 710 zvec = (zvec << 1) | ((bsBuffShadow >> bsLiveShadow) & 1); 711 } 712 nextSym = perm_zt[zvec - base_zt[zn]]; 713 } 714 } 715 716 this.last = lastShadow; 717 this.bsLive = bsLiveShadow; 718 this.bsBuff = bsBuffShadow; 719 } 720 721 private int getAndMoveToFrontDecode0(final int groupNo) throws IOException { 722 final InputStream inShadow = this.in; 723 final Data dataShadow = this.data; 724 final int zt = dataShadow.selector[groupNo] & 0xff; 725 final int[] limit_zt = dataShadow.limit[zt]; 726 int zn = dataShadow.minLens[zt]; 727 int zvec = bsR(zn); 728 int bsLiveShadow = this.bsLive; 729 int bsBuffShadow = this.bsBuff; 730 731 while (zvec > limit_zt[zn]) { 732 zn++; 733 while (bsLiveShadow < 1) { 734 final int thech = inShadow.read(); 735 736 if (thech >= 0) { 737 bsBuffShadow = (bsBuffShadow << 8) | thech; 738 bsLiveShadow += 8; 739 continue; 740 } else { 741 throw new IOException("unexpected end of stream"); 742 } 743 } 744 bsLiveShadow--; 745 zvec = (zvec << 1) | ((bsBuffShadow >> bsLiveShadow) & 1); 746 } 747 748 this.bsLive = bsLiveShadow; 749 this.bsBuff = bsBuffShadow; 750 751 return dataShadow.perm[zt][zvec - dataShadow.base[zt][zn]]; 752 } 753 754 private void setupBlock() throws IOException { 755 if (this.data == null) { 756 return; 757 } 758 759 final int[] cftab = this.data.cftab; 760 final int[] tt = this.data.initTT(this.last + 1); 761 final byte[] ll8 = this.data.ll8; 762 cftab[0] = 0; 763 System.arraycopy(this.data.unzftab, 0, cftab, 1, 256); 764 765 for (int i = 1, c = cftab[0]; i <= 256; i++) { 766 c += cftab[i]; 767 cftab[i] = c; 768 } 769 770 for (int i = 0, lastShadow = this.last; i <= lastShadow; i++) { 771 tt[cftab[ll8[i] & 0xff]++] = i; 772 } 773 774 if ((this.origPtr < 0) || (this.origPtr >= tt.length)) { 775 throw new IOException("stream corrupted"); 776 } 777 778 this.su_tPos = tt[this.origPtr]; 779 this.su_count = 0; 780 this.su_i2 = 0; 781 this.su_ch2 = 256; /* not a char and not EOF */ 782 783 if (this.blockRandomised) { 784 this.su_rNToGo = 0; 785 this.su_rTPos = 0; 786 setupRandPartA(); 787 } else { 788 setupNoRandPartA(); 789 } 790 } 791 792 private void setupRandPartA() throws IOException { 793 if (this.su_i2 <= this.last) { 794 this.su_chPrev = this.su_ch2; 795 int su_ch2Shadow = this.data.ll8[this.su_tPos] & 0xff; 796 this.su_tPos = this.data.tt[this.su_tPos]; 797 if (this.su_rNToGo == 0) { 798 this.su_rNToGo = Rand.rNums(this.su_rTPos) - 1; 799 if (++this.su_rTPos == 512) { 800 this.su_rTPos = 0; 801 } 802 } else { 803 this.su_rNToGo--; 804 } 805 this.su_ch2 = su_ch2Shadow ^= (this.su_rNToGo == 1) ? 1 : 0; 806 this.su_i2++; 807 this.currentChar = su_ch2Shadow; 808 this.currentState = RAND_PART_B_STATE; 809 this.crc.updateCRC(su_ch2Shadow); 810 } else { 811 endBlock(); 812 initBlock(); 813 setupBlock(); 814 } 815 } 816 817 private void setupNoRandPartA() throws IOException { 818 if (this.su_i2 <= this.last) { 819 this.su_chPrev = this.su_ch2; 820 int su_ch2Shadow = this.data.ll8[this.su_tPos] & 0xff; 821 this.su_ch2 = su_ch2Shadow; 822 this.su_tPos = this.data.tt[this.su_tPos]; 823 this.su_i2++; 824 this.currentChar = su_ch2Shadow; 825 this.currentState = NO_RAND_PART_B_STATE; 826 this.crc.updateCRC(su_ch2Shadow); 827 } else { 828 this.currentState = NO_RAND_PART_A_STATE; 829 endBlock(); 830 initBlock(); 831 setupBlock(); 832 } 833 } 834 835 private void setupRandPartB() throws IOException { 836 if (this.su_ch2 != this.su_chPrev) { 837 this.currentState = RAND_PART_A_STATE; 838 this.su_count = 1; 839 setupRandPartA(); 840 } else if (++this.su_count >= 4) { 841 this.su_z = (char) (this.data.ll8[this.su_tPos] & 0xff); 842 this.su_tPos = this.data.tt[this.su_tPos]; 843 if (this.su_rNToGo == 0) { 844 this.su_rNToGo = Rand.rNums(this.su_rTPos) - 1; 845 if (++this.su_rTPos == 512) { 846 this.su_rTPos = 0; 847 } 848 } else { 849 this.su_rNToGo--; 850 } 851 this.su_j2 = 0; 852 this.currentState = RAND_PART_C_STATE; 853 if (this.su_rNToGo == 1) { 854 this.su_z ^= 1; 855 } 856 setupRandPartC(); 857 } else { 858 this.currentState = RAND_PART_A_STATE; 859 setupRandPartA(); 860 } 861 } 862 863 private void setupRandPartC() throws IOException { 864 if (this.su_j2 < this.su_z) { 865 this.currentChar = this.su_ch2; 866 this.crc.updateCRC(this.su_ch2); 867 this.su_j2++; 868 } else { 869 this.currentState = RAND_PART_A_STATE; 870 this.su_i2++; 871 this.su_count = 0; 872 setupRandPartA(); 873 } 874 } 875 876 private void setupNoRandPartB() throws IOException { 877 if (this.su_ch2 != this.su_chPrev) { 878 this.su_count = 1; 879 setupNoRandPartA(); 880 } else if (++this.su_count >= 4) { 881 this.su_z = (char) (this.data.ll8[this.su_tPos] & 0xff); 882 this.su_tPos = this.data.tt[this.su_tPos]; 883 this.su_j2 = 0; 884 setupNoRandPartC(); 885 } else { 886 setupNoRandPartA(); 887 } 888 } 889 890 private void setupNoRandPartC() throws IOException { 891 if (this.su_j2 < this.su_z) { 892 int su_ch2Shadow = this.su_ch2; 893 this.currentChar = su_ch2Shadow; 894 this.crc.updateCRC(su_ch2Shadow); 895 this.su_j2++; 896 this.currentState = NO_RAND_PART_C_STATE; 897 } else { 898 this.su_i2++; 899 this.su_count = 0; 900 setupNoRandPartA(); 901 } 902 } 903 904 private static final class Data extends Object { 905 906 // (with blockSize 900k) 907 final boolean[] inUse = new boolean[256]; // 256 byte 908 909 final byte[] seqToUnseq = new byte[256]; // 256 byte 910 final byte[] selector = new byte[MAX_SELECTORS]; // 18002 byte 911 final byte[] selectorMtf = new byte[MAX_SELECTORS]; // 18002 byte 912 913 /** 914 * Freq table collected to save a pass over the data during 915 * decompression. 916 */ 917 final int[] unzftab = new int[256]; // 1024 byte 918 919 final int[][] limit = new int[N_GROUPS][MAX_ALPHA_SIZE]; // 6192 byte 920 final int[][] base = new int[N_GROUPS][MAX_ALPHA_SIZE]; // 6192 byte 921 final int[][] perm = new int[N_GROUPS][MAX_ALPHA_SIZE]; // 6192 byte 922 final int[] minLens = new int[N_GROUPS]; // 24 byte 923 924 final int[] cftab = new int[257]; // 1028 byte 925 final char[] getAndMoveToFrontDecode_yy = new char[256]; // 512 byte 926 final char[][] temp_charArray2d = new char[N_GROUPS][MAX_ALPHA_SIZE]; // 3096 927 // byte 928 final byte[] recvDecodingTables_pos = new byte[N_GROUPS]; // 6 byte 929 // --------------- 930 // 60798 byte 931 932 int[] tt; // 3600000 byte 933 byte[] ll8; // 900000 byte 934 935 // --------------- 936 // 4560782 byte 937 // =============== 938 939 Data(int blockSize100k) { 940 super(); 941 942 this.ll8 = new byte[blockSize100k * BZip2Constants.BASEBLOCKSIZE]; 943 } 944 945 /** 946 * Initializes the {@link #tt} array. 947 * 948 * This method is called when the required length of the array is known. 949 * I don't initialize it at construction time to avoid unneccessary 950 * memory allocation when compressing small files. 951 */ 952 final int[] initTT(int length) { 953 int[] ttShadow = this.tt; 954 955 // tt.length should always be >= length, but theoretically 956 // it can happen, if the compressor mixed small and large 957 // blocks. Normally only the last block will be smaller 958 // than others. 959 if ((ttShadow == null) || (ttShadow.length < length)) { 960 this.tt = ttShadow = new int[length]; 961 } 962 963 return ttShadow; 964 } 965 966 } 967 968 }