www.pudn.com > RakNet-2.52.zip > decompress.c


 
/*-------------------------------------------------------------*/ 
/*--- Decompression machinery                               ---*/ 
/*---                                          decompress.c ---*/ 
/*-------------------------------------------------------------*/ 
 
/*-- 
  This file is a part of bzip2 and/or libbzip2, a program and 
  library for lossless, block-sorting data compression. 
 
  Copyright (C) 1996-2005 Julian R Seward.  All rights reserved. 
 
  Redistribution and use in source and binary forms, with or without 
  modification, are permitted provided that the following conditions 
  are met: 
 
  1. Redistributions of source code must retain the above copyright 
     notice, this list of conditions and the following disclaimer. 
 
  2. The origin of this software must not be misrepresented; you must  
     not claim that you wrote the original software.  If you use this  
     software in a product, an acknowledgment in the product  
     documentation would be appreciated but is not required. 
 
  3. Altered source versions must be plainly marked as such, and must 
     not be misrepresented as being the original software. 
 
  4. The name of the author may not be used to endorse or promote  
     products derived from this software without specific prior written  
     permission. 
 
  THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS 
  OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 
  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
  ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY 
  DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 
  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE 
  GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 
  WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 
  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 
  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
 
  Julian Seward, Cambridge, UK. 
  jseward@bzip.org 
  bzip2/libbzip2 version 1.0 of 21 March 2000 
 
  This program is based on (at least) the work of: 
     Mike Burrows 
     David Wheeler 
     Peter Fenwick 
     Alistair Moffat 
     Radford Neal 
     Ian H. Witten 
     Robert Sedgewick 
     Jon L. Bentley 
 
  For more information on these sources, see the manual. 
--*/ 
 
 
#include "bzlib_private.h" 
 
 
/*---------------------------------------------------*/ 
static 
void makeMaps_d ( DState* s ) 
{ 
   Int32 i; 
   s->nInUse = 0; 
   for (i = 0; i < 256; i++) 
      if (s->inUse[i]) { 
         s->seqToUnseq[s->nInUse] = i; 
         s->nInUse++; 
      } 
} 
 
 
/*---------------------------------------------------*/ 
#define RETURN(rrr)                               \ 
   { retVal = rrr; goto save_state_and_return; }; 
 
#define GET_BITS(lll,vvv,nnn)                     \ 
   case lll: s->state = lll;                      \ 
   while (True) {                                 \ 
      if (s->bsLive >= nnn) {                     \ 
         UInt32 v;                                \ 
         v = (s->bsBuff >>                        \ 
             (s->bsLive-nnn)) & ((1 << nnn)-1);   \ 
         s->bsLive -= nnn;                        \ 
         vvv = v;                                 \ 
         break;                                   \ 
      }                                           \ 
      if (s->strm->avail_in == 0) RETURN(BZ_OK);  \ 
      s->bsBuff                                   \ 
         = (s->bsBuff << 8) |                     \ 
           ((UInt32)                              \ 
              (*((UChar*)(s->strm->next_in))));   \ 
      s->bsLive += 8;                             \ 
      s->strm->next_in++;                         \ 
      s->strm->avail_in--;                        \ 
      s->strm->total_in_lo32++;                   \ 
      if (s->strm->total_in_lo32 == 0)            \ 
         s->strm->total_in_hi32++;                \ 
   } 
 
#define GET_UCHAR(lll,uuu)                        \ 
   GET_BITS(lll,uuu,8) 
 
#define GET_BIT(lll,uuu)                          \ 
   GET_BITS(lll,uuu,1) 
 
/*---------------------------------------------------*/ 
#define GET_MTF_VAL(label1,label2,lval)           \ 
{                                                 \ 
   if (groupPos == 0) {                           \ 
      groupNo++;                                  \ 
      if (groupNo >= nSelectors)                  \ 
         RETURN(BZ_DATA_ERROR);                   \ 
      groupPos = BZ_G_SIZE;                       \ 
      gSel = s->selector[groupNo];                \ 
      gMinlen = s->minLens[gSel];                 \ 
      gLimit = &(s->limit[gSel][0]);              \ 
      gPerm = &(s->perm[gSel][0]);                \ 
      gBase = &(s->base[gSel][0]);                \ 
   }                                              \ 
   groupPos--;                                    \ 
   zn = gMinlen;                                  \ 
   GET_BITS(label1, zvec, zn);                    \ 
   while (1) {                                    \ 
      if (zn > 20 /* the longest code */)         \ 
         RETURN(BZ_DATA_ERROR);                   \ 
      if (zvec <= gLimit[zn]) break;              \ 
      zn++;                                       \ 
      GET_BIT(label2, zj);                        \ 
      zvec = (zvec << 1) | zj;                    \ 
   };                                             \ 
   if (zvec - gBase[zn] < 0                       \ 
       || zvec - gBase[zn] >= BZ_MAX_ALPHA_SIZE)  \ 
      RETURN(BZ_DATA_ERROR);                      \ 
   lval = gPerm[zvec - gBase[zn]];                \ 
} 
 
 
/*---------------------------------------------------*/ 
Int32 BZ2_decompress ( DState* s ) 
{ 
   UChar      uc; 
   Int32      retVal; 
   Int32      minLen, maxLen; 
   bz_stream* strm = s->strm; 
 
   /* stuff that needs to be saved/restored */ 
   Int32  i; 
   Int32  j; 
   Int32  t; 
   Int32  alphaSize; 
   Int32  nGroups; 
   Int32  nSelectors; 
   Int32  EOB; 
   Int32  groupNo; 
   Int32  groupPos; 
   Int32  nextSym; 
   Int32  nblockMAX; 
   Int32  nblock; 
   Int32  es; 
   Int32  N; 
   Int32  curr; 
   Int32  zt; 
   Int32  zn;  
   Int32  zvec; 
   Int32  zj; 
   Int32  gSel; 
   Int32  gMinlen; 
   Int32* gLimit; 
   Int32* gBase; 
   Int32* gPerm; 
 
   if (s->state == BZ_X_MAGIC_1) { 
      /*initialise the save area*/ 
      s->save_i           = 0; 
      s->save_j           = 0; 
      s->save_t           = 0; 
      s->save_alphaSize   = 0; 
      s->save_nGroups     = 0; 
      s->save_nSelectors  = 0; 
      s->save_EOB         = 0; 
      s->save_groupNo     = 0; 
      s->save_groupPos    = 0; 
      s->save_nextSym     = 0; 
      s->save_nblockMAX   = 0; 
      s->save_nblock      = 0; 
      s->save_es          = 0; 
      s->save_N           = 0; 
      s->save_curr        = 0; 
      s->save_zt          = 0; 
      s->save_zn          = 0; 
      s->save_zvec        = 0; 
      s->save_zj          = 0; 
      s->save_gSel        = 0; 
      s->save_gMinlen     = 0; 
      s->save_gLimit      = NULL; 
      s->save_gBase       = NULL; 
      s->save_gPerm       = NULL; 
   } 
 
   /*restore from the save area*/ 
   i           = s->save_i; 
   j           = s->save_j; 
   t           = s->save_t; 
   alphaSize   = s->save_alphaSize; 
   nGroups     = s->save_nGroups; 
   nSelectors  = s->save_nSelectors; 
   EOB         = s->save_EOB; 
   groupNo     = s->save_groupNo; 
   groupPos    = s->save_groupPos; 
   nextSym     = s->save_nextSym; 
   nblockMAX   = s->save_nblockMAX; 
   nblock      = s->save_nblock; 
   es          = s->save_es; 
   N           = s->save_N; 
   curr        = s->save_curr; 
   zt          = s->save_zt; 
   zn          = s->save_zn;  
   zvec        = s->save_zvec; 
   zj          = s->save_zj; 
   gSel        = s->save_gSel; 
   gMinlen     = s->save_gMinlen; 
   gLimit      = s->save_gLimit; 
   gBase       = s->save_gBase; 
   gPerm       = s->save_gPerm; 
 
   retVal = BZ_OK; 
 
   switch (s->state) { 
 
      GET_UCHAR(BZ_X_MAGIC_1, uc); 
      if (uc != BZ_HDR_B) RETURN(BZ_DATA_ERROR_MAGIC); 
 
      GET_UCHAR(BZ_X_MAGIC_2, uc); 
      if (uc != BZ_HDR_Z) RETURN(BZ_DATA_ERROR_MAGIC); 
 
      GET_UCHAR(BZ_X_MAGIC_3, uc) 
      if (uc != BZ_HDR_h) RETURN(BZ_DATA_ERROR_MAGIC); 
 
      GET_BITS(BZ_X_MAGIC_4, s->blockSize100k, 8) 
      if (s->blockSize100k < (BZ_HDR_0 + 1) ||  
          s->blockSize100k > (BZ_HDR_0 + 9)) RETURN(BZ_DATA_ERROR_MAGIC); 
      s->blockSize100k -= BZ_HDR_0; 
 
      if (s->smallDecompress) { 
         s->ll16 = BZALLOC( s->blockSize100k * 100000 * sizeof(UInt16) ); 
         s->ll4  = BZALLOC(  
                      ((1 + s->blockSize100k * 100000) >> 1) * sizeof(UChar)  
                   ); 
         if (s->ll16 == NULL || s->ll4 == NULL) RETURN(BZ_MEM_ERROR); 
      } else { 
         s->tt  = BZALLOC( s->blockSize100k * 100000 * sizeof(Int32) ); 
         if (s->tt == NULL) RETURN(BZ_MEM_ERROR); 
      } 
 
      GET_UCHAR(BZ_X_BLKHDR_1, uc); 
 
      if (uc == 0x17) goto endhdr_2; 
      if (uc != 0x31) RETURN(BZ_DATA_ERROR); 
      GET_UCHAR(BZ_X_BLKHDR_2, uc); 
      if (uc != 0x41) RETURN(BZ_DATA_ERROR); 
      GET_UCHAR(BZ_X_BLKHDR_3, uc); 
      if (uc != 0x59) RETURN(BZ_DATA_ERROR); 
      GET_UCHAR(BZ_X_BLKHDR_4, uc); 
      if (uc != 0x26) RETURN(BZ_DATA_ERROR); 
      GET_UCHAR(BZ_X_BLKHDR_5, uc); 
      if (uc != 0x53) RETURN(BZ_DATA_ERROR); 
      GET_UCHAR(BZ_X_BLKHDR_6, uc); 
      if (uc != 0x59) RETURN(BZ_DATA_ERROR); 
 
      s->currBlockNo++; 
      if (s->verbosity >= 2) 
         VPrintf1 ( "\n    [%d: huff+mtf ", s->currBlockNo ); 
  
      s->storedBlockCRC = 0; 
      GET_UCHAR(BZ_X_BCRC_1, uc); 
      s->storedBlockCRC = (s->storedBlockCRC << 8) | ((UInt32)uc); 
      GET_UCHAR(BZ_X_BCRC_2, uc); 
      s->storedBlockCRC = (s->storedBlockCRC << 8) | ((UInt32)uc); 
      GET_UCHAR(BZ_X_BCRC_3, uc); 
      s->storedBlockCRC = (s->storedBlockCRC << 8) | ((UInt32)uc); 
      GET_UCHAR(BZ_X_BCRC_4, uc); 
      s->storedBlockCRC = (s->storedBlockCRC << 8) | ((UInt32)uc); 
 
      GET_BITS(BZ_X_RANDBIT, s->blockRandomised, 1); 
 
      s->origPtr = 0; 
      GET_UCHAR(BZ_X_ORIGPTR_1, uc); 
      s->origPtr = (s->origPtr << 8) | ((Int32)uc); 
      GET_UCHAR(BZ_X_ORIGPTR_2, uc); 
      s->origPtr = (s->origPtr << 8) | ((Int32)uc); 
      GET_UCHAR(BZ_X_ORIGPTR_3, uc); 
      s->origPtr = (s->origPtr << 8) | ((Int32)uc); 
 
      if (s->origPtr < 0) 
         RETURN(BZ_DATA_ERROR); 
      if (s->origPtr > 10 + 100000*s->blockSize100k)  
         RETURN(BZ_DATA_ERROR); 
 
      /*--- Receive the mapping table ---*/ 
      for (i = 0; i < 16; i++) { 
         GET_BIT(BZ_X_MAPPING_1, uc); 
         if (uc == 1)  
            s->inUse16[i] = True; else  
            s->inUse16[i] = False; 
      } 
 
      for (i = 0; i < 256; i++) s->inUse[i] = False; 
 
      for (i = 0; i < 16; i++) 
         if (s->inUse16[i]) 
            for (j = 0; j < 16; j++) { 
               GET_BIT(BZ_X_MAPPING_2, uc); 
               if (uc == 1) s->inUse[i * 16 + j] = True; 
            } 
      makeMaps_d ( s ); 
      if (s->nInUse == 0) RETURN(BZ_DATA_ERROR); 
      alphaSize = s->nInUse+2; 
 
      /*--- Now the selectors ---*/ 
      GET_BITS(BZ_X_SELECTOR_1, nGroups, 3); 
      if (nGroups < 2 || nGroups > 6) RETURN(BZ_DATA_ERROR); 
      GET_BITS(BZ_X_SELECTOR_2, nSelectors, 15); 
      if (nSelectors < 1) RETURN(BZ_DATA_ERROR); 
      for (i = 0; i < nSelectors; i++) { 
         j = 0; 
         while (True) { 
            GET_BIT(BZ_X_SELECTOR_3, uc); 
            if (uc == 0) break; 
            j++; 
            if (j >= nGroups) RETURN(BZ_DATA_ERROR); 
         } 
         s->selectorMtf[i] = j; 
      } 
 
      /*--- Undo the MTF values for the selectors. ---*/ 
      { 
         UChar pos[BZ_N_GROUPS], tmp, v; 
         for (v = 0; v < nGroups; v++) pos[v] = v; 
    
         for (i = 0; i < nSelectors; i++) { 
            v = s->selectorMtf[i]; 
            tmp = pos[v]; 
            while (v > 0) { pos[v] = pos[v-1]; v--; } 
            pos[0] = tmp; 
            s->selector[i] = tmp; 
         } 
      } 
 
      /*--- Now the coding tables ---*/ 
      for (t = 0; t < nGroups; t++) { 
         GET_BITS(BZ_X_CODING_1, curr, 5); 
         for (i = 0; i < alphaSize; i++) { 
            while (True) { 
               if (curr < 1 || curr > 20) RETURN(BZ_DATA_ERROR); 
               GET_BIT(BZ_X_CODING_2, uc); 
               if (uc == 0) break; 
               GET_BIT(BZ_X_CODING_3, uc); 
               if (uc == 0) curr++; else curr--; 
            } 
            s->len[t][i] = curr; 
         } 
      } 
 
      /*--- Create the Huffman decoding tables ---*/ 
      for (t = 0; t < nGroups; t++) { 
         minLen = 32; 
         maxLen = 0; 
         for (i = 0; i < alphaSize; i++) { 
            if (s->len[t][i] > maxLen) maxLen = s->len[t][i]; 
            if (s->len[t][i] < minLen) minLen = s->len[t][i]; 
         } 
         BZ2_hbCreateDecodeTables (  
            &(s->limit[t][0]),  
            &(s->base[t][0]),  
            &(s->perm[t][0]),  
            &(s->len[t][0]), 
            minLen, maxLen, alphaSize 
         ); 
         s->minLens[t] = minLen; 
      } 
 
      /*--- Now the MTF values ---*/ 
 
      EOB      = s->nInUse+1; 
      nblockMAX = 100000 * s->blockSize100k; 
      groupNo  = -1; 
      groupPos = 0; 
 
      for (i = 0; i <= 255; i++) s->unzftab[i] = 0; 
 
      /*-- MTF init --*/ 
      { 
         Int32 ii, jj, kk; 
         kk = MTFA_SIZE-1; 
         for (ii = 256 / MTFL_SIZE - 1; ii >= 0; ii--) { 
            for (jj = MTFL_SIZE-1; jj >= 0; jj--) { 
               s->mtfa[kk] = (UChar)(ii * MTFL_SIZE + jj); 
               kk--; 
            } 
            s->mtfbase[ii] = kk + 1; 
         } 
      } 
      /*-- end MTF init --*/ 
 
      nblock = 0; 
      GET_MTF_VAL(BZ_X_MTF_1, BZ_X_MTF_2, nextSym); 
 
      while (True) { 
 
         if (nextSym == EOB) break; 
 
         if (nextSym == BZ_RUNA || nextSym == BZ_RUNB) { 
 
            es = -1; 
            N = 1; 
            do { 
               if (nextSym == BZ_RUNA) es = es + (0+1) * N; else 
               if (nextSym == BZ_RUNB) es = es + (1+1) * N; 
               N = N * 2; 
               GET_MTF_VAL(BZ_X_MTF_3, BZ_X_MTF_4, nextSym); 
            } 
               while (nextSym == BZ_RUNA || nextSym == BZ_RUNB); 
 
            es++; 
            uc = s->seqToUnseq[ s->mtfa[s->mtfbase[0]] ]; 
            s->unzftab[uc] += es; 
 
            if (s->smallDecompress) 
               while (es > 0) { 
                  if (nblock >= nblockMAX) RETURN(BZ_DATA_ERROR); 
                  s->ll16[nblock] = (UInt16)uc; 
                  nblock++; 
                  es--; 
               } 
            else 
               while (es > 0) { 
                  if (nblock >= nblockMAX) RETURN(BZ_DATA_ERROR); 
                  s->tt[nblock] = (UInt32)uc; 
                  nblock++; 
                  es--; 
               }; 
 
            continue; 
 
         } else { 
 
            if (nblock >= nblockMAX) RETURN(BZ_DATA_ERROR); 
 
            /*-- uc = MTF ( nextSym-1 ) --*/ 
            { 
               Int32 ii, jj, kk, pp, lno, off; 
               UInt32 nn; 
               nn = (UInt32)(nextSym - 1); 
 
               if (nn < MTFL_SIZE) { 
                  /* avoid general-case expense */ 
                  pp = s->mtfbase[0]; 
                  uc = s->mtfa[pp+nn]; 
                  while (nn > 3) { 
                     Int32 z = pp+nn; 
                     s->mtfa[(z)  ] = s->mtfa[(z)-1]; 
                     s->mtfa[(z)-1] = s->mtfa[(z)-2]; 
                     s->mtfa[(z)-2] = s->mtfa[(z)-3]; 
                     s->mtfa[(z)-3] = s->mtfa[(z)-4]; 
                     nn -= 4; 
                  } 
                  while (nn > 0) {  
                     s->mtfa[(pp+nn)] = s->mtfa[(pp+nn)-1]; nn--;  
                  }; 
                  s->mtfa[pp] = uc; 
               } else {  
                  /* general case */ 
                  lno = nn / MTFL_SIZE; 
                  off = nn % MTFL_SIZE; 
                  pp = s->mtfbase[lno] + off; 
                  uc = s->mtfa[pp]; 
                  while (pp > s->mtfbase[lno]) {  
                     s->mtfa[pp] = s->mtfa[pp-1]; pp--;  
                  }; 
                  s->mtfbase[lno]++; 
                  while (lno > 0) { 
                     s->mtfbase[lno]--; 
                     s->mtfa[s->mtfbase[lno]]  
                        = s->mtfa[s->mtfbase[lno-1] + MTFL_SIZE - 1]; 
                     lno--; 
                  } 
                  s->mtfbase[0]--; 
                  s->mtfa[s->mtfbase[0]] = uc; 
                  if (s->mtfbase[0] == 0) { 
                     kk = MTFA_SIZE-1; 
                     for (ii = 256 / MTFL_SIZE-1; ii >= 0; ii--) { 
                        for (jj = MTFL_SIZE-1; jj >= 0; jj--) { 
                           s->mtfa[kk] = s->mtfa[s->mtfbase[ii] + jj]; 
                           kk--; 
                        } 
                        s->mtfbase[ii] = kk + 1; 
                     } 
                  } 
               } 
            } 
            /*-- end uc = MTF ( nextSym-1 ) --*/ 
 
            s->unzftab[s->seqToUnseq[uc]]++; 
            if (s->smallDecompress) 
               s->ll16[nblock] = (UInt16)(s->seqToUnseq[uc]); else 
               s->tt[nblock]   = (UInt32)(s->seqToUnseq[uc]); 
            nblock++; 
 
            GET_MTF_VAL(BZ_X_MTF_5, BZ_X_MTF_6, nextSym); 
            continue; 
         } 
      } 
 
      /* Now we know what nblock is, we can do a better sanity 
         check on s->origPtr. 
      */ 
      if (s->origPtr < 0 || s->origPtr >= nblock) 
         RETURN(BZ_DATA_ERROR); 
 
      /*-- Set up cftab to facilitate generation of T^(-1) --*/ 
      s->cftab[0] = 0; 
      for (i = 1; i <= 256; i++) s->cftab[i] = s->unzftab[i-1]; 
      for (i = 1; i <= 256; i++) s->cftab[i] += s->cftab[i-1]; 
      for (i = 0; i <= 256; i++) { 
         if (s->cftab[i] < 0 || s->cftab[i] > nblock) { 
            /* s->cftab[i] can legitimately be == nblock */ 
            RETURN(BZ_DATA_ERROR); 
         } 
      } 
 
      s->state_out_len = 0; 
      s->state_out_ch  = 0; 
      BZ_INITIALISE_CRC ( s->calculatedBlockCRC ); 
      s->state = BZ_X_OUTPUT; 
      if (s->verbosity >= 2) VPrintf0 ( "rt+rld" ); 
 
      if (s->smallDecompress) { 
 
         /*-- Make a copy of cftab, used in generation of T --*/ 
         for (i = 0; i <= 256; i++) s->cftabCopy[i] = s->cftab[i]; 
 
         /*-- compute the T vector --*/ 
         for (i = 0; i < nblock; i++) { 
            uc = (UChar)(s->ll16[i]); 
            SET_LL(i, s->cftabCopy[uc]); 
            s->cftabCopy[uc]++; 
         } 
 
         /*-- Compute T^(-1) by pointer reversal on T --*/ 
         i = s->origPtr; 
         j = GET_LL(i); 
         do { 
            Int32 tmp = GET_LL(j); 
            SET_LL(j, i); 
            i = j; 
            j = tmp; 
         } 
            while (i != s->origPtr); 
 
         s->tPos = s->origPtr; 
         s->nblock_used = 0; 
         if (s->blockRandomised) { 
            BZ_RAND_INIT_MASK; 
            BZ_GET_SMALL(s->k0); s->nblock_used++; 
            BZ_RAND_UPD_MASK; s->k0 ^= BZ_RAND_MASK;  
         } else { 
            BZ_GET_SMALL(s->k0); s->nblock_used++; 
         } 
 
      } else { 
 
         /*-- compute the T^(-1) vector --*/ 
         for (i = 0; i < nblock; i++) { 
            uc = (UChar)(s->tt[i] & 0xff); 
            s->tt[s->cftab[uc]] |= (i << 8); 
            s->cftab[uc]++; 
         } 
 
         s->tPos = s->tt[s->origPtr] >> 8; 
         s->nblock_used = 0; 
         if (s->blockRandomised) { 
            BZ_RAND_INIT_MASK; 
            BZ_GET_FAST(s->k0); s->nblock_used++; 
            BZ_RAND_UPD_MASK; s->k0 ^= BZ_RAND_MASK;  
         } else { 
            BZ_GET_FAST(s->k0); s->nblock_used++; 
         } 
 
      } 
 
      RETURN(BZ_OK); 
 
 
 
    endhdr_2: 
 
      GET_UCHAR(BZ_X_ENDHDR_2, uc); 
      if (uc != 0x72) RETURN(BZ_DATA_ERROR); 
      GET_UCHAR(BZ_X_ENDHDR_3, uc); 
      if (uc != 0x45) RETURN(BZ_DATA_ERROR); 
      GET_UCHAR(BZ_X_ENDHDR_4, uc); 
      if (uc != 0x38) RETURN(BZ_DATA_ERROR); 
      GET_UCHAR(BZ_X_ENDHDR_5, uc); 
      if (uc != 0x50) RETURN(BZ_DATA_ERROR); 
      GET_UCHAR(BZ_X_ENDHDR_6, uc); 
      if (uc != 0x90) RETURN(BZ_DATA_ERROR); 
 
      s->storedCombinedCRC = 0; 
      GET_UCHAR(BZ_X_CCRC_1, uc); 
      s->storedCombinedCRC = (s->storedCombinedCRC << 8) | ((UInt32)uc); 
      GET_UCHAR(BZ_X_CCRC_2, uc); 
      s->storedCombinedCRC = (s->storedCombinedCRC << 8) | ((UInt32)uc); 
      GET_UCHAR(BZ_X_CCRC_3, uc); 
      s->storedCombinedCRC = (s->storedCombinedCRC << 8) | ((UInt32)uc); 
      GET_UCHAR(BZ_X_CCRC_4, uc); 
      s->storedCombinedCRC = (s->storedCombinedCRC << 8) | ((UInt32)uc); 
 
      s->state = BZ_X_IDLE; 
      RETURN(BZ_STREAM_END); 
 
      default: AssertH ( False, 4001 ); 
   } 
 
   AssertH ( False, 4002 ); 
 
   save_state_and_return: 
 
   s->save_i           = i; 
   s->save_j           = j; 
   s->save_t           = t; 
   s->save_alphaSize   = alphaSize; 
   s->save_nGroups     = nGroups; 
   s->save_nSelectors  = nSelectors; 
   s->save_EOB         = EOB; 
   s->save_groupNo     = groupNo; 
   s->save_groupPos    = groupPos; 
   s->save_nextSym     = nextSym; 
   s->save_nblockMAX   = nblockMAX; 
   s->save_nblock      = nblock; 
   s->save_es          = es; 
   s->save_N           = N; 
   s->save_curr        = curr; 
   s->save_zt          = zt; 
   s->save_zn          = zn; 
   s->save_zvec        = zvec; 
   s->save_zj          = zj; 
   s->save_gSel        = gSel; 
   s->save_gMinlen     = gMinlen; 
   s->save_gLimit      = gLimit; 
   s->save_gBase       = gBase; 
   s->save_gPerm       = gPerm; 
 
   return retVal;    
} 
 
 
/*-------------------------------------------------------------*/ 
/*--- end                                      decompress.c ---*/ 
/*-------------------------------------------------------------*/