xref: /illumos-gate/usr/src/common/bzip2/decompress.c (revision d1855c8182d5cf1cd290336767a7c8e7537c13a2)
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 
11    bzip2/libbzip2 version 1.0.6 of 6 September 2010
12    Copyright (C) 1996-2010 Julian Seward <jseward@bzip.org>
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    /* FALLTHROUGH */                              \
45    case lll: s->state = lll;                      \
46    while (True) {                                 \
47       if (s->bsLive >= nnn) {                     \
48          UInt32 v;                                \
49          v = (s->bsBuff >>                        \
50              (s->bsLive-nnn)) & ((1 << nnn)-1);   \
51          s->bsLive -= nnn;                        \
52          vvv = v;                                 \
53          break;                                   \
54       }                                           \
55       if (s->strm->avail_in == 0) RETURN(BZ_OK);  \
56       s->bsBuff                                   \
57          = (s->bsBuff << 8) |                     \
58            ((UInt32)                              \
59               (*((UChar*)(s->strm->next_in))));   \
60       s->bsLive += 8;                             \
61       s->strm->next_in++;                         \
62       s->strm->avail_in--;                        \
63       s->strm->total_in_lo32++;                   \
64       if (s->strm->total_in_lo32 == 0)            \
65          s->strm->total_in_hi32++;                \
66    }
67 
68 #define GET_UCHAR(lll,uuu)                        \
69    GET_BITS(lll,uuu,8)
70 
71 #define GET_BIT(lll,uuu)                          \
72    GET_BITS(lll,uuu,1)
73 
74 /*---------------------------------------------------*/
75 #define GET_MTF_VAL(label1,label2,lval)           \
76 {                                                 \
77    if (groupPos == 0) {                           \
78       groupNo++;                                  \
79       if (groupNo >= nSelectors)                  \
80          RETURN(BZ_DATA_ERROR);                   \
81       groupPos = BZ_G_SIZE;                       \
82       gSel = s->selector[groupNo];                \
83       gMinlen = s->minLens[gSel];                 \
84       gLimit = &(s->limit[gSel][0]);              \
85       gPerm = &(s->perm[gSel][0]);                \
86       gBase = &(s->base[gSel][0]);                \
87    }                                              \
88    groupPos--;                                    \
89    zn = gMinlen;                                  \
90    GET_BITS(label1, zvec, zn);                    \
91    while (1) {                                    \
92       if (zn > 20 /* the longest code */)         \
93          RETURN(BZ_DATA_ERROR);                   \
94       if (zvec <= gLimit[zn]) break;              \
95       zn++;                                       \
96       GET_BIT(label2, zj);                        \
97       zvec = (zvec << 1) | zj;                    \
98    };                                             \
99    if (zvec - gBase[zn] < 0                       \
100        || zvec - gBase[zn] >= BZ_MAX_ALPHA_SIZE)  \
101       RETURN(BZ_DATA_ERROR);                      \
102    lval = gPerm[zvec - gBase[zn]];                \
103 }
104 
105 
106 /*---------------------------------------------------*/
107 Int32 BZ2_decompress ( DState* s )
108 {
109    UChar      uc;
110    Int32      retVal;
111    Int32      minLen, maxLen;
112    bz_stream* strm = s->strm;
113 
114    /* stuff that needs to be saved/restored */
115    Int32  i;
116    Int32  j;
117    Int32  t;
118    Int32  alphaSize;
119    Int32  nGroups;
120    Int32  nSelectors;
121    Int32  EOB;
122    Int32  groupNo;
123    Int32  groupPos;
124    Int32  nextSym;
125    Int32  nblockMAX;
126    Int32  nblock;
127    Int32  es;
128    Int32  N;
129    Int32  curr;
130    Int32  zt;
131    Int32  zn;
132    Int32  zvec;
133    Int32  zj;
134    Int32  gSel;
135    Int32  gMinlen;
136    Int32* gLimit;
137    Int32* gBase;
138    Int32* gPerm;
139 
140    if (s->state == BZ_X_MAGIC_1) {
141       /*initialise the save area*/
142       s->save_i           = 0;
143       s->save_j           = 0;
144       s->save_t           = 0;
145       s->save_alphaSize   = 0;
146       s->save_nGroups     = 0;
147       s->save_nSelectors  = 0;
148       s->save_EOB         = 0;
149       s->save_groupNo     = 0;
150       s->save_groupPos    = 0;
151       s->save_nextSym     = 0;
152       s->save_nblockMAX   = 0;
153       s->save_nblock      = 0;
154       s->save_es          = 0;
155       s->save_N           = 0;
156       s->save_curr        = 0;
157       s->save_zt          = 0;
158       s->save_zn          = 0;
159       s->save_zvec        = 0;
160       s->save_zj          = 0;
161       s->save_gSel        = 0;
162       s->save_gMinlen     = 0;
163       s->save_gLimit      = NULL;
164       s->save_gBase       = NULL;
165       s->save_gPerm       = NULL;
166    }
167 
168    /*restore from the save area*/
169    i           = s->save_i;
170    j           = s->save_j;
171    t           = s->save_t;
172    alphaSize   = s->save_alphaSize;
173    nGroups     = s->save_nGroups;
174    nSelectors  = s->save_nSelectors;
175    EOB         = s->save_EOB;
176    groupNo     = s->save_groupNo;
177    groupPos    = s->save_groupPos;
178    nextSym     = s->save_nextSym;
179    nblockMAX   = s->save_nblockMAX;
180    nblock      = s->save_nblock;
181    es          = s->save_es;
182    N           = s->save_N;
183    curr        = s->save_curr;
184    zt          = s->save_zt;
185    zn          = s->save_zn;
186    zvec        = s->save_zvec;
187    zj          = s->save_zj;
188    gSel        = s->save_gSel;
189    gMinlen     = s->save_gMinlen;
190    gLimit      = s->save_gLimit;
191    gBase       = s->save_gBase;
192    gPerm       = s->save_gPerm;
193 
194    retVal = BZ_OK;
195 
196    switch (s->state) {
197 
198       GET_UCHAR(BZ_X_MAGIC_1, uc);
199       if (uc != BZ_HDR_B) RETURN(BZ_DATA_ERROR_MAGIC);
200 
201       GET_UCHAR(BZ_X_MAGIC_2, uc);
202       if (uc != BZ_HDR_Z) RETURN(BZ_DATA_ERROR_MAGIC);
203 
204       GET_UCHAR(BZ_X_MAGIC_3, uc)
205       if (uc != BZ_HDR_h) RETURN(BZ_DATA_ERROR_MAGIC);
206 
207       GET_BITS(BZ_X_MAGIC_4, s->blockSize100k, 8)
208       if (s->blockSize100k < (BZ_HDR_0 + 1) ||
209           s->blockSize100k > (BZ_HDR_0 + 9)) RETURN(BZ_DATA_ERROR_MAGIC);
210       s->blockSize100k -= BZ_HDR_0;
211 
212       if (s->smallDecompress) {
213          s->ll16 = BZALLOC( s->blockSize100k * 100000 * sizeof(UInt16) );
214          s->ll4  = BZALLOC(
215                       ((1 + s->blockSize100k * 100000) >> 1) * sizeof(UChar)
216                    );
217          if (s->ll16 == NULL || s->ll4 == NULL) RETURN(BZ_MEM_ERROR);
218       } else {
219          s->tt  = BZALLOC( s->blockSize100k * 100000 * sizeof(Int32) );
220          if (s->tt == NULL) RETURN(BZ_MEM_ERROR);
221       }
222 
223       GET_UCHAR(BZ_X_BLKHDR_1, uc);
224 
225       if (uc == 0x17) goto endhdr_2;
226       if (uc != 0x31) RETURN(BZ_DATA_ERROR);
227       GET_UCHAR(BZ_X_BLKHDR_2, uc);
228       if (uc != 0x41) RETURN(BZ_DATA_ERROR);
229       GET_UCHAR(BZ_X_BLKHDR_3, uc);
230       if (uc != 0x59) RETURN(BZ_DATA_ERROR);
231       GET_UCHAR(BZ_X_BLKHDR_4, uc);
232       if (uc != 0x26) RETURN(BZ_DATA_ERROR);
233       GET_UCHAR(BZ_X_BLKHDR_5, uc);
234       if (uc != 0x53) RETURN(BZ_DATA_ERROR);
235       GET_UCHAR(BZ_X_BLKHDR_6, uc);
236       if (uc != 0x59) RETURN(BZ_DATA_ERROR);
237 
238       s->currBlockNo++;
239       if (s->verbosity >= 2)
240          VPrintf1 ( "\n    [%d: huff+mtf ", s->currBlockNo );
241 
242       s->storedBlockCRC = 0;
243       GET_UCHAR(BZ_X_BCRC_1, uc);
244       s->storedBlockCRC = (s->storedBlockCRC << 8) | ((UInt32)uc);
245       GET_UCHAR(BZ_X_BCRC_2, uc);
246       s->storedBlockCRC = (s->storedBlockCRC << 8) | ((UInt32)uc);
247       GET_UCHAR(BZ_X_BCRC_3, uc);
248       s->storedBlockCRC = (s->storedBlockCRC << 8) | ((UInt32)uc);
249       GET_UCHAR(BZ_X_BCRC_4, uc);
250       s->storedBlockCRC = (s->storedBlockCRC << 8) | ((UInt32)uc);
251 
252       GET_BITS(BZ_X_RANDBIT, s->blockRandomised, 1);
253 
254       s->origPtr = 0;
255       GET_UCHAR(BZ_X_ORIGPTR_1, uc);
256       s->origPtr = (s->origPtr << 8) | ((Int32)uc);
257       GET_UCHAR(BZ_X_ORIGPTR_2, uc);
258       s->origPtr = (s->origPtr << 8) | ((Int32)uc);
259       GET_UCHAR(BZ_X_ORIGPTR_3, uc);
260       s->origPtr = (s->origPtr << 8) | ((Int32)uc);
261 
262       if (s->origPtr < 0)
263          RETURN(BZ_DATA_ERROR);
264       if (s->origPtr > 10 + 100000*s->blockSize100k)
265          RETURN(BZ_DATA_ERROR);
266 
267       /*--- Receive the mapping table ---*/
268       for (i = 0; i < 16; i++) {
269          GET_BIT(BZ_X_MAPPING_1, uc);
270          if (uc == 1)
271             s->inUse16[i] = True; else
272             s->inUse16[i] = False;
273       }
274 
275       for (i = 0; i < 256; i++) s->inUse[i] = False;
276 
277       for (i = 0; i < 16; i++)
278          if (s->inUse16[i])
279             for (j = 0; j < 16; j++) {
280                GET_BIT(BZ_X_MAPPING_2, uc);
281                if (uc == 1) s->inUse[i * 16 + j] = True;
282             }
283       makeMaps_d ( s );
284       if (s->nInUse == 0) RETURN(BZ_DATA_ERROR);
285       alphaSize = s->nInUse+2;
286 
287       /*--- Now the selectors ---*/
288       GET_BITS(BZ_X_SELECTOR_1, nGroups, 3);
289       if (nGroups < 2 || nGroups > 6) RETURN(BZ_DATA_ERROR);
290       GET_BITS(BZ_X_SELECTOR_2, nSelectors, 15);
291       if (nSelectors < 1) RETURN(BZ_DATA_ERROR);
292       for (i = 0; i < nSelectors; i++) {
293          j = 0;
294          while (True) {
295             GET_BIT(BZ_X_SELECTOR_3, uc);
296             if (uc == 0) break;
297             j++;
298             if (j >= nGroups) RETURN(BZ_DATA_ERROR);
299          }
300          s->selectorMtf[i] = j;
301       }
302 
303       /*--- Undo the MTF values for the selectors. ---*/
304       {
305          UChar pos[BZ_N_GROUPS], tmp, v;
306          for (v = 0; v < nGroups; v++) pos[v] = v;
307 
308          for (i = 0; i < nSelectors; i++) {
309             v = s->selectorMtf[i];
310             tmp = pos[v];
311             while (v > 0) { pos[v] = pos[v-1]; v--; }
312             pos[0] = tmp;
313             s->selector[i] = tmp;
314          }
315       }
316 
317       /*--- Now the coding tables ---*/
318       for (t = 0; t < nGroups; t++) {
319          GET_BITS(BZ_X_CODING_1, curr, 5);
320          for (i = 0; i < alphaSize; i++) {
321             while (True) {
322                if (curr < 1 || curr > 20) RETURN(BZ_DATA_ERROR);
323                GET_BIT(BZ_X_CODING_2, uc);
324                if (uc == 0) break;
325                GET_BIT(BZ_X_CODING_3, uc);
326                if (uc == 0) curr++; else curr--;
327             }
328             s->len[t][i] = curr;
329          }
330       }
331 
332       /*--- Create the Huffman decoding tables ---*/
333       for (t = 0; t < nGroups; t++) {
334          minLen = 32;
335          maxLen = 0;
336          for (i = 0; i < alphaSize; i++) {
337             if (s->len[t][i] > maxLen) maxLen = s->len[t][i];
338             if (s->len[t][i] < minLen) minLen = s->len[t][i];
339          }
340          BZ2_hbCreateDecodeTables (
341             &(s->limit[t][0]),
342             &(s->base[t][0]),
343             &(s->perm[t][0]),
344             &(s->len[t][0]),
345             minLen, maxLen, alphaSize
346          );
347          s->minLens[t] = minLen;
348       }
349 
350       /*--- Now the MTF values ---*/
351 
352       EOB      = s->nInUse+1;
353       nblockMAX = 100000 * s->blockSize100k;
354       groupNo  = -1;
355       groupPos = 0;
356 
357       for (i = 0; i <= 255; i++) s->unzftab[i] = 0;
358 
359       /*-- MTF init --*/
360       {
361          Int32 ii, jj, kk;
362          kk = MTFA_SIZE-1;
363          for (ii = 256 / MTFL_SIZE - 1; ii >= 0; ii--) {
364             for (jj = MTFL_SIZE-1; jj >= 0; jj--) {
365                s->mtfa[kk] = (UChar)(ii * MTFL_SIZE + jj);
366                kk--;
367             }
368             s->mtfbase[ii] = kk + 1;
369          }
370       }
371       /*-- end MTF init --*/
372 
373       nblock = 0;
374       GET_MTF_VAL(BZ_X_MTF_1, BZ_X_MTF_2, nextSym);
375 
376       while (True) {
377 
378          if (nextSym == EOB) break;
379 
380          if (nextSym == BZ_RUNA || nextSym == BZ_RUNB) {
381 
382             es = -1;
383             N = 1;
384             do {
385                /* Check that N doesn't get too big, so that es doesn't
386                   go negative.  The maximum value that can be
387                   RUNA/RUNB encoded is equal to the block size (post
388                   the initial RLE), viz, 900k, so bounding N at 2
389                   million should guard against overflow without
390                   rejecting any legitimate inputs. */
391                if (N >= 2*1024*1024) RETURN(BZ_DATA_ERROR);
392                if (nextSym == BZ_RUNA) es = es + (0+1) * N; else
393                if (nextSym == BZ_RUNB) es = es + (1+1) * N;
394                N = N * 2;
395                GET_MTF_VAL(BZ_X_MTF_3, BZ_X_MTF_4, nextSym);
396             }
397                while (nextSym == BZ_RUNA || nextSym == BZ_RUNB);
398 
399             es++;
400             uc = s->seqToUnseq[ s->mtfa[s->mtfbase[0]] ];
401             s->unzftab[uc] += es;
402 
403             if (s->smallDecompress)
404                while (es > 0) {
405                   if (nblock >= nblockMAX) RETURN(BZ_DATA_ERROR);
406                   s->ll16[nblock] = (UInt16)uc;
407                   nblock++;
408                   es--;
409                }
410             else
411                while (es > 0) {
412                   if (nblock >= nblockMAX) RETURN(BZ_DATA_ERROR);
413                   s->tt[nblock] = (UInt32)uc;
414                   nblock++;
415                   es--;
416                };
417 
418             continue;
419 
420          } else {
421 
422             if (nblock >= nblockMAX) RETURN(BZ_DATA_ERROR);
423 
424             /*-- uc = MTF ( nextSym-1 ) --*/
425             {
426                Int32 ii, jj, kk, pp, lno, off;
427                UInt32 nn;
428                nn = (UInt32)(nextSym - 1);
429 
430                if (nn < MTFL_SIZE) {
431                   /* avoid general-case expense */
432                   pp = s->mtfbase[0];
433                   uc = s->mtfa[pp+nn];
434                   while (nn > 3) {
435                      Int32 z = pp+nn;
436                      s->mtfa[(z)  ] = s->mtfa[(z)-1];
437                      s->mtfa[(z)-1] = s->mtfa[(z)-2];
438                      s->mtfa[(z)-2] = s->mtfa[(z)-3];
439                      s->mtfa[(z)-3] = s->mtfa[(z)-4];
440                      nn -= 4;
441                   }
442                   while (nn > 0) {
443                      s->mtfa[(pp+nn)] = s->mtfa[(pp+nn)-1]; nn--;
444                   };
445                   s->mtfa[pp] = uc;
446                } else {
447                   /* general case */
448                   lno = nn / MTFL_SIZE;
449                   off = nn % MTFL_SIZE;
450                   pp = s->mtfbase[lno] + off;
451                   uc = s->mtfa[pp];
452                   while (pp > s->mtfbase[lno]) {
453                      s->mtfa[pp] = s->mtfa[pp-1]; pp--;
454                   };
455                   s->mtfbase[lno]++;
456                   while (lno > 0) {
457                      s->mtfbase[lno]--;
458                      s->mtfa[s->mtfbase[lno]]
459                         = s->mtfa[s->mtfbase[lno-1] + MTFL_SIZE - 1];
460                      lno--;
461                   }
462                   s->mtfbase[0]--;
463                   s->mtfa[s->mtfbase[0]] = uc;
464                   if (s->mtfbase[0] == 0) {
465                      kk = MTFA_SIZE-1;
466                      for (ii = 256 / MTFL_SIZE-1; ii >= 0; ii--) {
467                         for (jj = MTFL_SIZE-1; jj >= 0; jj--) {
468                            s->mtfa[kk] = s->mtfa[s->mtfbase[ii] + jj];
469                            kk--;
470                         }
471                         s->mtfbase[ii] = kk + 1;
472                      }
473                   }
474                }
475             }
476             /*-- end uc = MTF ( nextSym-1 ) --*/
477 
478             s->unzftab[s->seqToUnseq[uc]]++;
479             if (s->smallDecompress)
480                s->ll16[nblock] = (UInt16)(s->seqToUnseq[uc]); else
481                s->tt[nblock]   = (UInt32)(s->seqToUnseq[uc]);
482             nblock++;
483 
484             GET_MTF_VAL(BZ_X_MTF_5, BZ_X_MTF_6, nextSym);
485             continue;
486          }
487       }
488 
489       /* Now we know what nblock is, we can do a better sanity
490          check on s->origPtr.
491       */
492       if (s->origPtr < 0 || s->origPtr >= nblock)
493          RETURN(BZ_DATA_ERROR);
494 
495       /*-- Set up cftab to facilitate generation of T^(-1) --*/
496       /* Check: unzftab entries in range. */
497       for (i = 0; i <= 255; i++) {
498          if (s->unzftab[i] < 0 || s->unzftab[i] > nblock)
499             RETURN(BZ_DATA_ERROR);
500       }
501       /* Actually generate cftab. */
502       s->cftab[0] = 0;
503       for (i = 1; i <= 256; i++) s->cftab[i] = s->unzftab[i-1];
504       for (i = 1; i <= 256; i++) s->cftab[i] += s->cftab[i-1];
505       /* Check: cftab entries in range. */
506       for (i = 0; i <= 256; i++) {
507          if (s->cftab[i] < 0 || s->cftab[i] > nblock) {
508             /* s->cftab[i] can legitimately be == nblock */
509             RETURN(BZ_DATA_ERROR)
510          }
511       }
512       /* Check: cftab entries non-descending. */
513       for (i = 1; i <= 256; i++) {
514          if (s->cftab[i-1] > s->cftab[i]) {
515             RETURN(BZ_DATA_ERROR)
516          }
517       }
518 
519       s->state_out_len = 0;
520       s->state_out_ch  = 0;
521       BZ_INITIALISE_CRC ( s->calculatedBlockCRC );
522       s->state = BZ_X_OUTPUT;
523       if (s->verbosity >= 2) VPrintf0 ( "rt+rld" );
524 
525       if (s->smallDecompress) {
526 
527          /*-- Make a copy of cftab, used in generation of T --*/
528          for (i = 0; i <= 256; i++) s->cftabCopy[i] = s->cftab[i];
529 
530          /*-- compute the T vector --*/
531          for (i = 0; i < nblock; i++) {
532             uc = (UChar)(s->ll16[i]);
533             SET_LL(i, s->cftabCopy[uc]);
534             s->cftabCopy[uc]++;
535          }
536 
537          /*-- Compute T^(-1) by pointer reversal on T --*/
538          i = s->origPtr;
539          j = GET_LL(i);
540          do {
541             Int32 tmp = GET_LL(j);
542             SET_LL(j, i);
543             i = j;
544             j = tmp;
545          }
546             while (i != s->origPtr);
547 
548          s->tPos = s->origPtr;
549          s->nblock_used = 0;
550          if (s->blockRandomised) {
551             BZ_RAND_INIT_MASK;
552             BZ_GET_SMALL(s->k0); s->nblock_used++;
553             BZ_RAND_UPD_MASK; s->k0 ^= BZ_RAND_MASK;
554          } else {
555             BZ_GET_SMALL(s->k0); s->nblock_used++;
556          }
557 
558       } else {
559 
560          /*-- compute the T^(-1) vector --*/
561          for (i = 0; i < nblock; i++) {
562             uc = (UChar)(s->tt[i] & 0xff);
563             s->tt[s->cftab[uc]] |= (i << 8);
564             s->cftab[uc]++;
565          }
566 
567          s->tPos = s->tt[s->origPtr] >> 8;
568          s->nblock_used = 0;
569          if (s->blockRandomised) {
570             BZ_RAND_INIT_MASK;
571             BZ_GET_FAST(s->k0); s->nblock_used++;
572             BZ_RAND_UPD_MASK; s->k0 ^= BZ_RAND_MASK;
573          } else {
574             BZ_GET_FAST(s->k0); s->nblock_used++;
575          }
576 
577       }
578 
579       RETURN(BZ_OK)
580 
581 
582 
583     endhdr_2:
584 
585       GET_UCHAR(BZ_X_ENDHDR_2, uc);
586       if (uc != 0x72) RETURN(BZ_DATA_ERROR);
587       GET_UCHAR(BZ_X_ENDHDR_3, uc);
588       if (uc != 0x45) RETURN(BZ_DATA_ERROR);
589       GET_UCHAR(BZ_X_ENDHDR_4, uc);
590       if (uc != 0x38) RETURN(BZ_DATA_ERROR);
591       GET_UCHAR(BZ_X_ENDHDR_5, uc);
592       if (uc != 0x50) RETURN(BZ_DATA_ERROR);
593       GET_UCHAR(BZ_X_ENDHDR_6, uc);
594       if (uc != 0x90) RETURN(BZ_DATA_ERROR);
595 
596       s->storedCombinedCRC = 0;
597       GET_UCHAR(BZ_X_CCRC_1, uc);
598       s->storedCombinedCRC = (s->storedCombinedCRC << 8) | ((UInt32)uc);
599       GET_UCHAR(BZ_X_CCRC_2, uc);
600       s->storedCombinedCRC = (s->storedCombinedCRC << 8) | ((UInt32)uc);
601       GET_UCHAR(BZ_X_CCRC_3, uc);
602       s->storedCombinedCRC = (s->storedCombinedCRC << 8) | ((UInt32)uc);
603       GET_UCHAR(BZ_X_CCRC_4, uc);
604       s->storedCombinedCRC = (s->storedCombinedCRC << 8) | ((UInt32)uc);
605 
606       s->state = BZ_X_IDLE;
607       RETURN(BZ_STREAM_END)
608 
609       default: AssertH ( False, 4001 );
610    }
611 
612    AssertH ( False, 4002 );
613 
614    save_state_and_return:
615 
616    s->save_i           = i;
617    s->save_j           = j;
618    s->save_t           = t;
619    s->save_alphaSize   = alphaSize;
620    s->save_nGroups     = nGroups;
621    s->save_nSelectors  = nSelectors;
622    s->save_EOB         = EOB;
623    s->save_groupNo     = groupNo;
624    s->save_groupPos    = groupPos;
625    s->save_nextSym     = nextSym;
626    s->save_nblockMAX   = nblockMAX;
627    s->save_nblock      = nblock;
628    s->save_es          = es;
629    s->save_N           = N;
630    s->save_curr        = curr;
631    s->save_zt          = zt;
632    s->save_zn          = zn;
633    s->save_zvec        = zvec;
634    s->save_zj          = zj;
635    s->save_gSel        = gSel;
636    s->save_gMinlen     = gMinlen;
637    s->save_gLimit      = gLimit;
638    s->save_gBase       = gBase;
639    s->save_gPerm       = gPerm;
640 
641    return retVal;
642 }
643 
644 
645 /*-------------------------------------------------------------*/
646 /*--- end                                      decompress.c ---*/
647 /*-------------------------------------------------------------*/
648