The Android Open Source Project | cfb3b27 | 2009-03-03 19:29:20 -0800 | [diff] [blame] | 1 | |
| 2 | /*-------------------------------------------------------------*/ |
| 3 | /*--- Decompression machinery ---*/ |
| 4 | /*--- decompress.c ---*/ |
| 5 | /*-------------------------------------------------------------*/ |
| 6 | |
| 7 | /* ------------------------------------------------------------------ |
| 8 | This file is part of bzip2/libbzip2, a program and library for |
| 9 | lossless, block-sorting data compression. |
| 10 | |
Elliott Hughes | 8645cf6 | 2021-12-08 15:07:46 -0800 | [diff] [blame] | 11 | bzip2/libbzip2 version 1.0.8 of 13 July 2019 |
| 12 | Copyright (C) 1996-2019 Julian Seward <jseward@acm.org> |
The Android Open Source Project | cfb3b27 | 2009-03-03 19:29:20 -0800 | [diff] [blame] | 13 | |
| 14 | Please read the WARNING, DISCLAIMER and PATENTS sections in the |
| 15 | README file. |
| 16 | |
| 17 | This program is released under the terms of the license contained |
| 18 | in the file LICENSE. |
| 19 | ------------------------------------------------------------------ */ |
| 20 | |
| 21 | |
| 22 | #include "bzlib_private.h" |
| 23 | |
| 24 | |
| 25 | /*---------------------------------------------------*/ |
| 26 | static |
| 27 | void makeMaps_d ( DState* s ) |
| 28 | { |
| 29 | Int32 i; |
| 30 | s->nInUse = 0; |
| 31 | for (i = 0; i < 256; i++) |
| 32 | if (s->inUse[i]) { |
| 33 | s->seqToUnseq[s->nInUse] = i; |
| 34 | s->nInUse++; |
| 35 | } |
| 36 | } |
| 37 | |
| 38 | |
| 39 | /*---------------------------------------------------*/ |
| 40 | #define RETURN(rrr) \ |
| 41 | { retVal = rrr; goto save_state_and_return; }; |
| 42 | |
| 43 | #define GET_BITS(lll,vvv,nnn) \ |
| 44 | case lll: s->state = lll; \ |
| 45 | while (True) { \ |
| 46 | if (s->bsLive >= nnn) { \ |
| 47 | UInt32 v; \ |
| 48 | v = (s->bsBuff >> \ |
| 49 | (s->bsLive-nnn)) & ((1 << nnn)-1); \ |
| 50 | s->bsLive -= nnn; \ |
| 51 | vvv = v; \ |
| 52 | break; \ |
| 53 | } \ |
| 54 | if (s->strm->avail_in == 0) RETURN(BZ_OK); \ |
| 55 | s->bsBuff \ |
| 56 | = (s->bsBuff << 8) | \ |
| 57 | ((UInt32) \ |
| 58 | (*((UChar*)(s->strm->next_in)))); \ |
| 59 | s->bsLive += 8; \ |
| 60 | s->strm->next_in++; \ |
| 61 | s->strm->avail_in--; \ |
| 62 | s->strm->total_in_lo32++; \ |
| 63 | if (s->strm->total_in_lo32 == 0) \ |
| 64 | s->strm->total_in_hi32++; \ |
| 65 | } |
| 66 | |
| 67 | #define GET_UCHAR(lll,uuu) \ |
| 68 | GET_BITS(lll,uuu,8) |
| 69 | |
| 70 | #define GET_BIT(lll,uuu) \ |
| 71 | GET_BITS(lll,uuu,1) |
| 72 | |
| 73 | /*---------------------------------------------------*/ |
| 74 | #define GET_MTF_VAL(label1,label2,lval) \ |
| 75 | { \ |
| 76 | if (groupPos == 0) { \ |
| 77 | groupNo++; \ |
| 78 | if (groupNo >= nSelectors) \ |
| 79 | RETURN(BZ_DATA_ERROR); \ |
| 80 | groupPos = BZ_G_SIZE; \ |
| 81 | gSel = s->selector[groupNo]; \ |
| 82 | gMinlen = s->minLens[gSel]; \ |
| 83 | gLimit = &(s->limit[gSel][0]); \ |
| 84 | gPerm = &(s->perm[gSel][0]); \ |
| 85 | gBase = &(s->base[gSel][0]); \ |
| 86 | } \ |
| 87 | groupPos--; \ |
| 88 | zn = gMinlen; \ |
| 89 | GET_BITS(label1, zvec, zn); \ |
| 90 | while (1) { \ |
| 91 | if (zn > 20 /* the longest code */) \ |
| 92 | RETURN(BZ_DATA_ERROR); \ |
| 93 | if (zvec <= gLimit[zn]) break; \ |
| 94 | zn++; \ |
| 95 | GET_BIT(label2, zj); \ |
| 96 | zvec = (zvec << 1) | zj; \ |
| 97 | }; \ |
| 98 | if (zvec - gBase[zn] < 0 \ |
| 99 | || zvec - gBase[zn] >= BZ_MAX_ALPHA_SIZE) \ |
| 100 | RETURN(BZ_DATA_ERROR); \ |
| 101 | lval = gPerm[zvec - gBase[zn]]; \ |
| 102 | } |
| 103 | |
| 104 | |
| 105 | /*---------------------------------------------------*/ |
| 106 | Int32 BZ2_decompress ( DState* s ) |
| 107 | { |
| 108 | UChar uc; |
| 109 | Int32 retVal; |
| 110 | Int32 minLen, maxLen; |
| 111 | bz_stream* strm = s->strm; |
| 112 | |
| 113 | /* stuff that needs to be saved/restored */ |
| 114 | Int32 i; |
| 115 | Int32 j; |
| 116 | Int32 t; |
| 117 | Int32 alphaSize; |
| 118 | Int32 nGroups; |
| 119 | Int32 nSelectors; |
| 120 | Int32 EOB; |
| 121 | Int32 groupNo; |
| 122 | Int32 groupPos; |
| 123 | Int32 nextSym; |
| 124 | Int32 nblockMAX; |
| 125 | Int32 nblock; |
| 126 | Int32 es; |
| 127 | Int32 N; |
| 128 | Int32 curr; |
| 129 | Int32 zt; |
| 130 | Int32 zn; |
| 131 | Int32 zvec; |
| 132 | Int32 zj; |
| 133 | Int32 gSel; |
| 134 | Int32 gMinlen; |
| 135 | Int32* gLimit; |
| 136 | Int32* gBase; |
| 137 | Int32* gPerm; |
| 138 | |
| 139 | if (s->state == BZ_X_MAGIC_1) { |
| 140 | /*initialise the save area*/ |
| 141 | s->save_i = 0; |
| 142 | s->save_j = 0; |
| 143 | s->save_t = 0; |
| 144 | s->save_alphaSize = 0; |
| 145 | s->save_nGroups = 0; |
| 146 | s->save_nSelectors = 0; |
| 147 | s->save_EOB = 0; |
| 148 | s->save_groupNo = 0; |
| 149 | s->save_groupPos = 0; |
| 150 | s->save_nextSym = 0; |
| 151 | s->save_nblockMAX = 0; |
| 152 | s->save_nblock = 0; |
| 153 | s->save_es = 0; |
| 154 | s->save_N = 0; |
| 155 | s->save_curr = 0; |
| 156 | s->save_zt = 0; |
| 157 | s->save_zn = 0; |
| 158 | s->save_zvec = 0; |
| 159 | s->save_zj = 0; |
| 160 | s->save_gSel = 0; |
| 161 | s->save_gMinlen = 0; |
| 162 | s->save_gLimit = NULL; |
| 163 | s->save_gBase = NULL; |
| 164 | s->save_gPerm = NULL; |
| 165 | } |
| 166 | |
| 167 | /*restore from the save area*/ |
| 168 | i = s->save_i; |
| 169 | j = s->save_j; |
| 170 | t = s->save_t; |
| 171 | alphaSize = s->save_alphaSize; |
| 172 | nGroups = s->save_nGroups; |
| 173 | nSelectors = s->save_nSelectors; |
| 174 | EOB = s->save_EOB; |
| 175 | groupNo = s->save_groupNo; |
| 176 | groupPos = s->save_groupPos; |
| 177 | nextSym = s->save_nextSym; |
| 178 | nblockMAX = s->save_nblockMAX; |
| 179 | nblock = s->save_nblock; |
| 180 | es = s->save_es; |
| 181 | N = s->save_N; |
| 182 | curr = s->save_curr; |
| 183 | zt = s->save_zt; |
| 184 | zn = s->save_zn; |
| 185 | zvec = s->save_zvec; |
| 186 | zj = s->save_zj; |
| 187 | gSel = s->save_gSel; |
| 188 | gMinlen = s->save_gMinlen; |
| 189 | gLimit = s->save_gLimit; |
| 190 | gBase = s->save_gBase; |
| 191 | gPerm = s->save_gPerm; |
| 192 | |
| 193 | retVal = BZ_OK; |
| 194 | |
| 195 | switch (s->state) { |
| 196 | |
| 197 | GET_UCHAR(BZ_X_MAGIC_1, uc); |
| 198 | if (uc != BZ_HDR_B) RETURN(BZ_DATA_ERROR_MAGIC); |
| 199 | |
| 200 | GET_UCHAR(BZ_X_MAGIC_2, uc); |
| 201 | if (uc != BZ_HDR_Z) RETURN(BZ_DATA_ERROR_MAGIC); |
| 202 | |
| 203 | GET_UCHAR(BZ_X_MAGIC_3, uc) |
| 204 | if (uc != BZ_HDR_h) RETURN(BZ_DATA_ERROR_MAGIC); |
| 205 | |
| 206 | GET_BITS(BZ_X_MAGIC_4, s->blockSize100k, 8) |
| 207 | if (s->blockSize100k < (BZ_HDR_0 + 1) || |
| 208 | s->blockSize100k > (BZ_HDR_0 + 9)) RETURN(BZ_DATA_ERROR_MAGIC); |
| 209 | s->blockSize100k -= BZ_HDR_0; |
| 210 | |
| 211 | if (s->smallDecompress) { |
| 212 | s->ll16 = BZALLOC( s->blockSize100k * 100000 * sizeof(UInt16) ); |
| 213 | s->ll4 = BZALLOC( |
| 214 | ((1 + s->blockSize100k * 100000) >> 1) * sizeof(UChar) |
| 215 | ); |
| 216 | if (s->ll16 == NULL || s->ll4 == NULL) RETURN(BZ_MEM_ERROR); |
| 217 | } else { |
| 218 | s->tt = BZALLOC( s->blockSize100k * 100000 * sizeof(Int32) ); |
| 219 | if (s->tt == NULL) RETURN(BZ_MEM_ERROR); |
| 220 | } |
| 221 | |
| 222 | GET_UCHAR(BZ_X_BLKHDR_1, uc); |
| 223 | |
| 224 | if (uc == 0x17) goto endhdr_2; |
| 225 | if (uc != 0x31) RETURN(BZ_DATA_ERROR); |
| 226 | GET_UCHAR(BZ_X_BLKHDR_2, uc); |
| 227 | if (uc != 0x41) RETURN(BZ_DATA_ERROR); |
| 228 | GET_UCHAR(BZ_X_BLKHDR_3, uc); |
| 229 | if (uc != 0x59) RETURN(BZ_DATA_ERROR); |
| 230 | GET_UCHAR(BZ_X_BLKHDR_4, uc); |
| 231 | if (uc != 0x26) RETURN(BZ_DATA_ERROR); |
| 232 | GET_UCHAR(BZ_X_BLKHDR_5, uc); |
| 233 | if (uc != 0x53) RETURN(BZ_DATA_ERROR); |
| 234 | GET_UCHAR(BZ_X_BLKHDR_6, uc); |
| 235 | if (uc != 0x59) RETURN(BZ_DATA_ERROR); |
| 236 | |
| 237 | s->currBlockNo++; |
| 238 | if (s->verbosity >= 2) |
| 239 | VPrintf1 ( "\n [%d: huff+mtf ", s->currBlockNo ); |
| 240 | |
| 241 | s->storedBlockCRC = 0; |
| 242 | GET_UCHAR(BZ_X_BCRC_1, uc); |
| 243 | s->storedBlockCRC = (s->storedBlockCRC << 8) | ((UInt32)uc); |
| 244 | GET_UCHAR(BZ_X_BCRC_2, uc); |
| 245 | s->storedBlockCRC = (s->storedBlockCRC << 8) | ((UInt32)uc); |
| 246 | GET_UCHAR(BZ_X_BCRC_3, uc); |
| 247 | s->storedBlockCRC = (s->storedBlockCRC << 8) | ((UInt32)uc); |
| 248 | GET_UCHAR(BZ_X_BCRC_4, uc); |
| 249 | s->storedBlockCRC = (s->storedBlockCRC << 8) | ((UInt32)uc); |
| 250 | |
| 251 | GET_BITS(BZ_X_RANDBIT, s->blockRandomised, 1); |
| 252 | |
| 253 | s->origPtr = 0; |
| 254 | GET_UCHAR(BZ_X_ORIGPTR_1, uc); |
| 255 | s->origPtr = (s->origPtr << 8) | ((Int32)uc); |
| 256 | GET_UCHAR(BZ_X_ORIGPTR_2, uc); |
| 257 | s->origPtr = (s->origPtr << 8) | ((Int32)uc); |
| 258 | GET_UCHAR(BZ_X_ORIGPTR_3, uc); |
| 259 | s->origPtr = (s->origPtr << 8) | ((Int32)uc); |
| 260 | |
| 261 | if (s->origPtr < 0) |
| 262 | RETURN(BZ_DATA_ERROR); |
| 263 | if (s->origPtr > 10 + 100000*s->blockSize100k) |
| 264 | RETURN(BZ_DATA_ERROR); |
| 265 | |
| 266 | /*--- Receive the mapping table ---*/ |
| 267 | for (i = 0; i < 16; i++) { |
| 268 | GET_BIT(BZ_X_MAPPING_1, uc); |
| 269 | if (uc == 1) |
| 270 | s->inUse16[i] = True; else |
| 271 | s->inUse16[i] = False; |
| 272 | } |
| 273 | |
| 274 | for (i = 0; i < 256; i++) s->inUse[i] = False; |
| 275 | |
| 276 | for (i = 0; i < 16; i++) |
| 277 | if (s->inUse16[i]) |
| 278 | for (j = 0; j < 16; j++) { |
| 279 | GET_BIT(BZ_X_MAPPING_2, uc); |
| 280 | if (uc == 1) s->inUse[i * 16 + j] = True; |
| 281 | } |
| 282 | makeMaps_d ( s ); |
| 283 | if (s->nInUse == 0) RETURN(BZ_DATA_ERROR); |
| 284 | alphaSize = s->nInUse+2; |
| 285 | |
| 286 | /*--- Now the selectors ---*/ |
| 287 | GET_BITS(BZ_X_SELECTOR_1, nGroups, 3); |
Elliott Hughes | 8645cf6 | 2021-12-08 15:07:46 -0800 | [diff] [blame] | 288 | if (nGroups < 2 || nGroups > BZ_N_GROUPS) RETURN(BZ_DATA_ERROR); |
The Android Open Source Project | cfb3b27 | 2009-03-03 19:29:20 -0800 | [diff] [blame] | 289 | GET_BITS(BZ_X_SELECTOR_2, nSelectors, 15); |
| 290 | if (nSelectors < 1) RETURN(BZ_DATA_ERROR); |
| 291 | for (i = 0; i < nSelectors; i++) { |
| 292 | j = 0; |
| 293 | while (True) { |
| 294 | GET_BIT(BZ_X_SELECTOR_3, uc); |
| 295 | if (uc == 0) break; |
| 296 | j++; |
| 297 | if (j >= nGroups) RETURN(BZ_DATA_ERROR); |
| 298 | } |
Elliott Hughes | 8645cf6 | 2021-12-08 15:07:46 -0800 | [diff] [blame] | 299 | /* Having more than BZ_MAX_SELECTORS doesn't make much sense |
| 300 | since they will never be used, but some implementations might |
| 301 | "round up" the number of selectors, so just ignore those. */ |
| 302 | if (i < BZ_MAX_SELECTORS) |
| 303 | s->selectorMtf[i] = j; |
The Android Open Source Project | cfb3b27 | 2009-03-03 19:29:20 -0800 | [diff] [blame] | 304 | } |
Elliott Hughes | 8645cf6 | 2021-12-08 15:07:46 -0800 | [diff] [blame] | 305 | if (nSelectors > BZ_MAX_SELECTORS) |
| 306 | nSelectors = BZ_MAX_SELECTORS; |
The Android Open Source Project | cfb3b27 | 2009-03-03 19:29:20 -0800 | [diff] [blame] | 307 | |
| 308 | /*--- Undo the MTF values for the selectors. ---*/ |
| 309 | { |
| 310 | UChar pos[BZ_N_GROUPS], tmp, v; |
| 311 | for (v = 0; v < nGroups; v++) pos[v] = v; |
| 312 | |
| 313 | for (i = 0; i < nSelectors; i++) { |
| 314 | v = s->selectorMtf[i]; |
| 315 | tmp = pos[v]; |
| 316 | while (v > 0) { pos[v] = pos[v-1]; v--; } |
| 317 | pos[0] = tmp; |
| 318 | s->selector[i] = tmp; |
| 319 | } |
| 320 | } |
| 321 | |
| 322 | /*--- Now the coding tables ---*/ |
| 323 | for (t = 0; t < nGroups; t++) { |
| 324 | GET_BITS(BZ_X_CODING_1, curr, 5); |
| 325 | for (i = 0; i < alphaSize; i++) { |
| 326 | while (True) { |
| 327 | if (curr < 1 || curr > 20) RETURN(BZ_DATA_ERROR); |
| 328 | GET_BIT(BZ_X_CODING_2, uc); |
| 329 | if (uc == 0) break; |
| 330 | GET_BIT(BZ_X_CODING_3, uc); |
| 331 | if (uc == 0) curr++; else curr--; |
| 332 | } |
| 333 | s->len[t][i] = curr; |
| 334 | } |
| 335 | } |
| 336 | |
| 337 | /*--- Create the Huffman decoding tables ---*/ |
| 338 | for (t = 0; t < nGroups; t++) { |
| 339 | minLen = 32; |
| 340 | maxLen = 0; |
| 341 | for (i = 0; i < alphaSize; i++) { |
| 342 | if (s->len[t][i] > maxLen) maxLen = s->len[t][i]; |
| 343 | if (s->len[t][i] < minLen) minLen = s->len[t][i]; |
| 344 | } |
| 345 | BZ2_hbCreateDecodeTables ( |
| 346 | &(s->limit[t][0]), |
| 347 | &(s->base[t][0]), |
| 348 | &(s->perm[t][0]), |
| 349 | &(s->len[t][0]), |
| 350 | minLen, maxLen, alphaSize |
| 351 | ); |
| 352 | s->minLens[t] = minLen; |
| 353 | } |
| 354 | |
| 355 | /*--- Now the MTF values ---*/ |
| 356 | |
| 357 | EOB = s->nInUse+1; |
| 358 | nblockMAX = 100000 * s->blockSize100k; |
| 359 | groupNo = -1; |
| 360 | groupPos = 0; |
| 361 | |
| 362 | for (i = 0; i <= 255; i++) s->unzftab[i] = 0; |
| 363 | |
| 364 | /*-- MTF init --*/ |
| 365 | { |
| 366 | Int32 ii, jj, kk; |
| 367 | kk = MTFA_SIZE-1; |
| 368 | for (ii = 256 / MTFL_SIZE - 1; ii >= 0; ii--) { |
| 369 | for (jj = MTFL_SIZE-1; jj >= 0; jj--) { |
| 370 | s->mtfa[kk] = (UChar)(ii * MTFL_SIZE + jj); |
| 371 | kk--; |
| 372 | } |
| 373 | s->mtfbase[ii] = kk + 1; |
| 374 | } |
| 375 | } |
| 376 | /*-- end MTF init --*/ |
| 377 | |
| 378 | nblock = 0; |
| 379 | GET_MTF_VAL(BZ_X_MTF_1, BZ_X_MTF_2, nextSym); |
| 380 | |
| 381 | while (True) { |
| 382 | |
| 383 | if (nextSym == EOB) break; |
| 384 | |
| 385 | if (nextSym == BZ_RUNA || nextSym == BZ_RUNB) { |
| 386 | |
| 387 | es = -1; |
| 388 | N = 1; |
| 389 | do { |
Nick Kralevich | 172b266 | 2010-09-20 17:21:30 -0700 | [diff] [blame] | 390 | /* Check that N doesn't get too big, so that es doesn't |
| 391 | go negative. The maximum value that can be |
| 392 | RUNA/RUNB encoded is equal to the block size (post |
| 393 | the initial RLE), viz, 900k, so bounding N at 2 |
| 394 | million should guard against overflow without |
| 395 | rejecting any legitimate inputs. */ |
| 396 | if (N >= 2*1024*1024) RETURN(BZ_DATA_ERROR); |
The Android Open Source Project | cfb3b27 | 2009-03-03 19:29:20 -0800 | [diff] [blame] | 397 | if (nextSym == BZ_RUNA) es = es + (0+1) * N; else |
| 398 | if (nextSym == BZ_RUNB) es = es + (1+1) * N; |
| 399 | N = N * 2; |
| 400 | GET_MTF_VAL(BZ_X_MTF_3, BZ_X_MTF_4, nextSym); |
| 401 | } |
| 402 | while (nextSym == BZ_RUNA || nextSym == BZ_RUNB); |
| 403 | |
| 404 | es++; |
| 405 | uc = s->seqToUnseq[ s->mtfa[s->mtfbase[0]] ]; |
| 406 | s->unzftab[uc] += es; |
| 407 | |
| 408 | if (s->smallDecompress) |
| 409 | while (es > 0) { |
| 410 | if (nblock >= nblockMAX) RETURN(BZ_DATA_ERROR); |
| 411 | s->ll16[nblock] = (UInt16)uc; |
| 412 | nblock++; |
| 413 | es--; |
| 414 | } |
| 415 | else |
| 416 | while (es > 0) { |
| 417 | if (nblock >= nblockMAX) RETURN(BZ_DATA_ERROR); |
| 418 | s->tt[nblock] = (UInt32)uc; |
| 419 | nblock++; |
| 420 | es--; |
| 421 | }; |
| 422 | |
| 423 | continue; |
| 424 | |
| 425 | } else { |
| 426 | |
| 427 | if (nblock >= nblockMAX) RETURN(BZ_DATA_ERROR); |
| 428 | |
| 429 | /*-- uc = MTF ( nextSym-1 ) --*/ |
| 430 | { |
| 431 | Int32 ii, jj, kk, pp, lno, off; |
| 432 | UInt32 nn; |
| 433 | nn = (UInt32)(nextSym - 1); |
| 434 | |
| 435 | if (nn < MTFL_SIZE) { |
| 436 | /* avoid general-case expense */ |
| 437 | pp = s->mtfbase[0]; |
| 438 | uc = s->mtfa[pp+nn]; |
| 439 | while (nn > 3) { |
| 440 | Int32 z = pp+nn; |
| 441 | s->mtfa[(z) ] = s->mtfa[(z)-1]; |
| 442 | s->mtfa[(z)-1] = s->mtfa[(z)-2]; |
| 443 | s->mtfa[(z)-2] = s->mtfa[(z)-3]; |
| 444 | s->mtfa[(z)-3] = s->mtfa[(z)-4]; |
| 445 | nn -= 4; |
| 446 | } |
| 447 | while (nn > 0) { |
| 448 | s->mtfa[(pp+nn)] = s->mtfa[(pp+nn)-1]; nn--; |
| 449 | }; |
| 450 | s->mtfa[pp] = uc; |
| 451 | } else { |
| 452 | /* general case */ |
| 453 | lno = nn / MTFL_SIZE; |
| 454 | off = nn % MTFL_SIZE; |
| 455 | pp = s->mtfbase[lno] + off; |
| 456 | uc = s->mtfa[pp]; |
| 457 | while (pp > s->mtfbase[lno]) { |
| 458 | s->mtfa[pp] = s->mtfa[pp-1]; pp--; |
| 459 | }; |
| 460 | s->mtfbase[lno]++; |
| 461 | while (lno > 0) { |
| 462 | s->mtfbase[lno]--; |
| 463 | s->mtfa[s->mtfbase[lno]] |
| 464 | = s->mtfa[s->mtfbase[lno-1] + MTFL_SIZE - 1]; |
| 465 | lno--; |
| 466 | } |
| 467 | s->mtfbase[0]--; |
| 468 | s->mtfa[s->mtfbase[0]] = uc; |
| 469 | if (s->mtfbase[0] == 0) { |
| 470 | kk = MTFA_SIZE-1; |
| 471 | for (ii = 256 / MTFL_SIZE-1; ii >= 0; ii--) { |
| 472 | for (jj = MTFL_SIZE-1; jj >= 0; jj--) { |
| 473 | s->mtfa[kk] = s->mtfa[s->mtfbase[ii] + jj]; |
| 474 | kk--; |
| 475 | } |
| 476 | s->mtfbase[ii] = kk + 1; |
| 477 | } |
| 478 | } |
| 479 | } |
| 480 | } |
| 481 | /*-- end uc = MTF ( nextSym-1 ) --*/ |
| 482 | |
| 483 | s->unzftab[s->seqToUnseq[uc]]++; |
| 484 | if (s->smallDecompress) |
| 485 | s->ll16[nblock] = (UInt16)(s->seqToUnseq[uc]); else |
| 486 | s->tt[nblock] = (UInt32)(s->seqToUnseq[uc]); |
| 487 | nblock++; |
| 488 | |
| 489 | GET_MTF_VAL(BZ_X_MTF_5, BZ_X_MTF_6, nextSym); |
| 490 | continue; |
| 491 | } |
| 492 | } |
| 493 | |
| 494 | /* Now we know what nblock is, we can do a better sanity |
| 495 | check on s->origPtr. |
| 496 | */ |
| 497 | if (s->origPtr < 0 || s->origPtr >= nblock) |
| 498 | RETURN(BZ_DATA_ERROR); |
| 499 | |
| 500 | /*-- Set up cftab to facilitate generation of T^(-1) --*/ |
Nick Kralevich | 172b266 | 2010-09-20 17:21:30 -0700 | [diff] [blame] | 501 | /* Check: unzftab entries in range. */ |
| 502 | for (i = 0; i <= 255; i++) { |
| 503 | if (s->unzftab[i] < 0 || s->unzftab[i] > nblock) |
| 504 | RETURN(BZ_DATA_ERROR); |
| 505 | } |
| 506 | /* Actually generate cftab. */ |
The Android Open Source Project | cfb3b27 | 2009-03-03 19:29:20 -0800 | [diff] [blame] | 507 | s->cftab[0] = 0; |
| 508 | for (i = 1; i <= 256; i++) s->cftab[i] = s->unzftab[i-1]; |
| 509 | for (i = 1; i <= 256; i++) s->cftab[i] += s->cftab[i-1]; |
Nick Kralevich | 172b266 | 2010-09-20 17:21:30 -0700 | [diff] [blame] | 510 | /* Check: cftab entries in range. */ |
The Android Open Source Project | cfb3b27 | 2009-03-03 19:29:20 -0800 | [diff] [blame] | 511 | for (i = 0; i <= 256; i++) { |
| 512 | if (s->cftab[i] < 0 || s->cftab[i] > nblock) { |
| 513 | /* s->cftab[i] can legitimately be == nblock */ |
| 514 | RETURN(BZ_DATA_ERROR); |
| 515 | } |
| 516 | } |
Nick Kralevich | 172b266 | 2010-09-20 17:21:30 -0700 | [diff] [blame] | 517 | /* Check: cftab entries non-descending. */ |
| 518 | for (i = 1; i <= 256; i++) { |
| 519 | if (s->cftab[i-1] > s->cftab[i]) { |
| 520 | RETURN(BZ_DATA_ERROR); |
| 521 | } |
| 522 | } |
The Android Open Source Project | cfb3b27 | 2009-03-03 19:29:20 -0800 | [diff] [blame] | 523 | |
| 524 | s->state_out_len = 0; |
| 525 | s->state_out_ch = 0; |
| 526 | BZ_INITIALISE_CRC ( s->calculatedBlockCRC ); |
| 527 | s->state = BZ_X_OUTPUT; |
| 528 | if (s->verbosity >= 2) VPrintf0 ( "rt+rld" ); |
| 529 | |
| 530 | if (s->smallDecompress) { |
| 531 | |
| 532 | /*-- Make a copy of cftab, used in generation of T --*/ |
| 533 | for (i = 0; i <= 256; i++) s->cftabCopy[i] = s->cftab[i]; |
| 534 | |
| 535 | /*-- compute the T vector --*/ |
| 536 | for (i = 0; i < nblock; i++) { |
| 537 | uc = (UChar)(s->ll16[i]); |
| 538 | SET_LL(i, s->cftabCopy[uc]); |
| 539 | s->cftabCopy[uc]++; |
| 540 | } |
| 541 | |
| 542 | /*-- Compute T^(-1) by pointer reversal on T --*/ |
| 543 | i = s->origPtr; |
| 544 | j = GET_LL(i); |
| 545 | do { |
| 546 | Int32 tmp = GET_LL(j); |
| 547 | SET_LL(j, i); |
| 548 | i = j; |
| 549 | j = tmp; |
| 550 | } |
| 551 | while (i != s->origPtr); |
| 552 | |
| 553 | s->tPos = s->origPtr; |
| 554 | s->nblock_used = 0; |
| 555 | if (s->blockRandomised) { |
| 556 | BZ_RAND_INIT_MASK; |
| 557 | BZ_GET_SMALL(s->k0); s->nblock_used++; |
| 558 | BZ_RAND_UPD_MASK; s->k0 ^= BZ_RAND_MASK; |
| 559 | } else { |
| 560 | BZ_GET_SMALL(s->k0); s->nblock_used++; |
| 561 | } |
| 562 | |
| 563 | } else { |
| 564 | |
| 565 | /*-- compute the T^(-1) vector --*/ |
| 566 | for (i = 0; i < nblock; i++) { |
| 567 | uc = (UChar)(s->tt[i] & 0xff); |
| 568 | s->tt[s->cftab[uc]] |= (i << 8); |
| 569 | s->cftab[uc]++; |
| 570 | } |
| 571 | |
| 572 | s->tPos = s->tt[s->origPtr] >> 8; |
| 573 | s->nblock_used = 0; |
| 574 | if (s->blockRandomised) { |
| 575 | BZ_RAND_INIT_MASK; |
| 576 | BZ_GET_FAST(s->k0); s->nblock_used++; |
| 577 | BZ_RAND_UPD_MASK; s->k0 ^= BZ_RAND_MASK; |
| 578 | } else { |
| 579 | BZ_GET_FAST(s->k0); s->nblock_used++; |
| 580 | } |
| 581 | |
| 582 | } |
| 583 | |
| 584 | RETURN(BZ_OK); |
| 585 | |
| 586 | |
| 587 | |
| 588 | endhdr_2: |
| 589 | |
| 590 | GET_UCHAR(BZ_X_ENDHDR_2, uc); |
| 591 | if (uc != 0x72) RETURN(BZ_DATA_ERROR); |
| 592 | GET_UCHAR(BZ_X_ENDHDR_3, uc); |
| 593 | if (uc != 0x45) RETURN(BZ_DATA_ERROR); |
| 594 | GET_UCHAR(BZ_X_ENDHDR_4, uc); |
| 595 | if (uc != 0x38) RETURN(BZ_DATA_ERROR); |
| 596 | GET_UCHAR(BZ_X_ENDHDR_5, uc); |
| 597 | if (uc != 0x50) RETURN(BZ_DATA_ERROR); |
| 598 | GET_UCHAR(BZ_X_ENDHDR_6, uc); |
| 599 | if (uc != 0x90) RETURN(BZ_DATA_ERROR); |
| 600 | |
| 601 | s->storedCombinedCRC = 0; |
| 602 | GET_UCHAR(BZ_X_CCRC_1, uc); |
| 603 | s->storedCombinedCRC = (s->storedCombinedCRC << 8) | ((UInt32)uc); |
| 604 | GET_UCHAR(BZ_X_CCRC_2, uc); |
| 605 | s->storedCombinedCRC = (s->storedCombinedCRC << 8) | ((UInt32)uc); |
| 606 | GET_UCHAR(BZ_X_CCRC_3, uc); |
| 607 | s->storedCombinedCRC = (s->storedCombinedCRC << 8) | ((UInt32)uc); |
| 608 | GET_UCHAR(BZ_X_CCRC_4, uc); |
| 609 | s->storedCombinedCRC = (s->storedCombinedCRC << 8) | ((UInt32)uc); |
| 610 | |
| 611 | s->state = BZ_X_IDLE; |
| 612 | RETURN(BZ_STREAM_END); |
| 613 | |
| 614 | default: AssertH ( False, 4001 ); |
| 615 | } |
| 616 | |
| 617 | AssertH ( False, 4002 ); |
| 618 | |
| 619 | save_state_and_return: |
| 620 | |
| 621 | s->save_i = i; |
| 622 | s->save_j = j; |
| 623 | s->save_t = t; |
| 624 | s->save_alphaSize = alphaSize; |
| 625 | s->save_nGroups = nGroups; |
| 626 | s->save_nSelectors = nSelectors; |
| 627 | s->save_EOB = EOB; |
| 628 | s->save_groupNo = groupNo; |
| 629 | s->save_groupPos = groupPos; |
| 630 | s->save_nextSym = nextSym; |
| 631 | s->save_nblockMAX = nblockMAX; |
| 632 | s->save_nblock = nblock; |
| 633 | s->save_es = es; |
| 634 | s->save_N = N; |
| 635 | s->save_curr = curr; |
| 636 | s->save_zt = zt; |
| 637 | s->save_zn = zn; |
| 638 | s->save_zvec = zvec; |
| 639 | s->save_zj = zj; |
| 640 | s->save_gSel = gSel; |
| 641 | s->save_gMinlen = gMinlen; |
| 642 | s->save_gLimit = gLimit; |
| 643 | s->save_gBase = gBase; |
| 644 | s->save_gPerm = gPerm; |
| 645 | |
| 646 | return retVal; |
| 647 | } |
| 648 | |
| 649 | |
| 650 | /*-------------------------------------------------------------*/ |
| 651 | /*--- end decompress.c ---*/ |
| 652 | /*-------------------------------------------------------------*/ |