diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,5 @@
+# bz2
+
+## 0.1.0.0
+
+Initial release
diff --git a/LICENSE b/LICENSE
new file mode 100644
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,11 @@
+Copyright Vanessa McHale (c) 2020
+
+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. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
+
+3. Neither the name of the copyright holder nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 COPYRIGHT HOLDER OR CONTRIBUTORS 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.
diff --git a/README.md b/README.md
new file mode 100644
--- /dev/null
+++ b/README.md
@@ -0,0 +1,3 @@
+# bz2
+
+Low-level bindings to [bzip2](https://www.sourceware.org/bzip2/). 
diff --git a/bz2.cabal b/bz2.cabal
new file mode 100644
--- /dev/null
+++ b/bz2.cabal
@@ -0,0 +1,60 @@
+cabal-version:   1.18
+name:            bz2
+version:         0.1.0.0
+license:         BSD3
+license-file:    LICENSE
+copyright:       Copyright: (c) 2020 Vanessa McHale
+maintainer:      vamchale@gmail.com
+author:          Vanessa McHale
+bug-reports:     https://hub.darcs.net/vmchale/bz2/issues
+synopsis:        Bindings to libbz2
+description:     Low-level bindings to libbz2 using c2hs
+category:        Compression
+build-type:      Simple
+
+extra-doc-files:
+    README.md
+    CHANGELOG.md
+
+source-repository head
+    type:     darcs
+    location: https://hub.darcs.net/vmchale/bz2
+
+flag cross
+    description: Set this flag if cross-compiling
+    default:     False
+    manual:      True
+
+library
+    exposed-modules:
+        Codec.Compression.BZip.Foreign
+
+    c-sources:
+        cbits/bzlib.c
+        cbits/randtable.c
+        cbits/crctable.c
+        cbits/compress.c
+        cbits/blocksort.c
+        cbits/huffman.c
+        cbits/decompress.c
+
+    hs-source-dirs:   src
+
+    default-language: Haskell2010
+    include-dirs:     cbits
+    install-includes: cbits/bzlib.h
+    ghc-options:      -Wall
+    build-depends:
+        base >=4.4 && <5,
+        bytestring -any
+
+    if !flag(cross)
+        build-tool-depends: c2hs:c2hs >=0.28
+
+    if impl(ghc >=8.0)
+        ghc-options:
+            -Wincomplete-uni-patterns -Wincomplete-record-updates
+            -Wredundant-constraints
+
+    if impl(ghc >=8.4)
+        ghc-options: -Wmissing-export-lists
diff --git a/cbits/blocksort.c b/cbits/blocksort.c
new file mode 100644
--- /dev/null
+++ b/cbits/blocksort.c
@@ -0,0 +1,1094 @@
+
+/*-------------------------------------------------------------*/
+/*--- Block sorting machinery                               ---*/
+/*---                                           blocksort.c ---*/
+/*-------------------------------------------------------------*/
+
+/* ------------------------------------------------------------------
+   This file is part of bzip2/libbzip2, a program and library for
+   lossless, block-sorting data compression.
+
+   bzip2/libbzip2 version 1.0.8 of 13 July 2019
+   Copyright (C) 1996-2019 Julian Seward <jseward@acm.org>
+
+   Please read the WARNING, DISCLAIMER and PATENTS sections in the 
+   README file.
+
+   This program is released under the terms of the license contained
+   in the file LICENSE.
+   ------------------------------------------------------------------ */
+
+
+#include "bzlib_private.h"
+
+/*---------------------------------------------*/
+/*--- Fallback O(N log(N)^2) sorting        ---*/
+/*--- algorithm, for repetitive blocks      ---*/
+/*---------------------------------------------*/
+
+/*---------------------------------------------*/
+static 
+__inline__
+void fallbackSimpleSort ( UInt32* fmap, 
+                          UInt32* eclass, 
+                          Int32   lo, 
+                          Int32   hi )
+{
+   Int32 i, j, tmp;
+   UInt32 ec_tmp;
+
+   if (lo == hi) return;
+
+   if (hi - lo > 3) {
+      for ( i = hi-4; i >= lo; i-- ) {
+         tmp = fmap[i];
+         ec_tmp = eclass[tmp];
+         for ( j = i+4; j <= hi && ec_tmp > eclass[fmap[j]]; j += 4 )
+            fmap[j-4] = fmap[j];
+         fmap[j-4] = tmp;
+      }
+   }
+
+   for ( i = hi-1; i >= lo; i-- ) {
+      tmp = fmap[i];
+      ec_tmp = eclass[tmp];
+      for ( j = i+1; j <= hi && ec_tmp > eclass[fmap[j]]; j++ )
+         fmap[j-1] = fmap[j];
+      fmap[j-1] = tmp;
+   }
+}
+
+
+/*---------------------------------------------*/
+#define fswap(zz1, zz2) \
+   { Int32 zztmp = zz1; zz1 = zz2; zz2 = zztmp; }
+
+#define fvswap(zzp1, zzp2, zzn)       \
+{                                     \
+   Int32 yyp1 = (zzp1);               \
+   Int32 yyp2 = (zzp2);               \
+   Int32 yyn  = (zzn);                \
+   while (yyn > 0) {                  \
+      fswap(fmap[yyp1], fmap[yyp2]);  \
+      yyp1++; yyp2++; yyn--;          \
+   }                                  \
+}
+
+
+#define fmin(a,b) ((a) < (b)) ? (a) : (b)
+
+#define fpush(lz,hz) { stackLo[sp] = lz; \
+                       stackHi[sp] = hz; \
+                       sp++; }
+
+#define fpop(lz,hz) { sp--;              \
+                      lz = stackLo[sp];  \
+                      hz = stackHi[sp]; }
+
+#define FALLBACK_QSORT_SMALL_THRESH 10
+#define FALLBACK_QSORT_STACK_SIZE   100
+
+
+static
+void fallbackQSort3 ( UInt32* fmap, 
+                      UInt32* eclass,
+                      Int32   loSt, 
+                      Int32   hiSt )
+{
+   Int32 unLo, unHi, ltLo, gtHi, n, m;
+   Int32 sp, lo, hi;
+   UInt32 med, r, r3;
+   Int32 stackLo[FALLBACK_QSORT_STACK_SIZE];
+   Int32 stackHi[FALLBACK_QSORT_STACK_SIZE];
+
+   r = 0;
+
+   sp = 0;
+   fpush ( loSt, hiSt );
+
+   while (sp > 0) {
+
+      AssertH ( sp < FALLBACK_QSORT_STACK_SIZE - 1, 1004 );
+
+      fpop ( lo, hi );
+      if (hi - lo < FALLBACK_QSORT_SMALL_THRESH) {
+         fallbackSimpleSort ( fmap, eclass, lo, hi );
+         continue;
+      }
+
+      /* Random partitioning.  Median of 3 sometimes fails to
+         avoid bad cases.  Median of 9 seems to help but 
+         looks rather expensive.  This too seems to work but
+         is cheaper.  Guidance for the magic constants 
+         7621 and 32768 is taken from Sedgewick's algorithms
+         book, chapter 35.
+      */
+      r = ((r * 7621) + 1) % 32768;
+      r3 = r % 3;
+      if (r3 == 0) med = eclass[fmap[lo]]; else
+      if (r3 == 1) med = eclass[fmap[(lo+hi)>>1]]; else
+                   med = eclass[fmap[hi]];
+
+      unLo = ltLo = lo;
+      unHi = gtHi = hi;
+
+      while (1) {
+         while (1) {
+            if (unLo > unHi) break;
+            n = (Int32)eclass[fmap[unLo]] - (Int32)med;
+            if (n == 0) { 
+               fswap(fmap[unLo], fmap[ltLo]); 
+               ltLo++; unLo++; 
+               continue; 
+            };
+            if (n > 0) break;
+            unLo++;
+         }
+         while (1) {
+            if (unLo > unHi) break;
+            n = (Int32)eclass[fmap[unHi]] - (Int32)med;
+            if (n == 0) { 
+               fswap(fmap[unHi], fmap[gtHi]); 
+               gtHi--; unHi--; 
+               continue; 
+            };
+            if (n < 0) break;
+            unHi--;
+         }
+         if (unLo > unHi) break;
+         fswap(fmap[unLo], fmap[unHi]); unLo++; unHi--;
+      }
+
+      AssertD ( unHi == unLo-1, "fallbackQSort3(2)" );
+
+      if (gtHi < ltLo) continue;
+
+      n = fmin(ltLo-lo, unLo-ltLo); fvswap(lo, unLo-n, n);
+      m = fmin(hi-gtHi, gtHi-unHi); fvswap(unLo, hi-m+1, m);
+
+      n = lo + unLo - ltLo - 1;
+      m = hi - (gtHi - unHi) + 1;
+
+      if (n - lo > hi - m) {
+         fpush ( lo, n );
+         fpush ( m, hi );
+      } else {
+         fpush ( m, hi );
+         fpush ( lo, n );
+      }
+   }
+}
+
+#undef fmin
+#undef fpush
+#undef fpop
+#undef fswap
+#undef fvswap
+#undef FALLBACK_QSORT_SMALL_THRESH
+#undef FALLBACK_QSORT_STACK_SIZE
+
+
+/*---------------------------------------------*/
+/* Pre:
+      nblock > 0
+      eclass exists for [0 .. nblock-1]
+      ((UChar*)eclass) [0 .. nblock-1] holds block
+      ptr exists for [0 .. nblock-1]
+
+   Post:
+      ((UChar*)eclass) [0 .. nblock-1] holds block
+      All other areas of eclass destroyed
+      fmap [0 .. nblock-1] holds sorted order
+      bhtab [ 0 .. 2+(nblock/32) ] destroyed
+*/
+
+#define       SET_BH(zz)  bhtab[(zz) >> 5] |= ((UInt32)1 << ((zz) & 31))
+#define     CLEAR_BH(zz)  bhtab[(zz) >> 5] &= ~((UInt32)1 << ((zz) & 31))
+#define     ISSET_BH(zz)  (bhtab[(zz) >> 5] & ((UInt32)1 << ((zz) & 31)))
+#define      WORD_BH(zz)  bhtab[(zz) >> 5]
+#define UNALIGNED_BH(zz)  ((zz) & 0x01f)
+
+static
+void fallbackSort ( UInt32* fmap, 
+                    UInt32* eclass, 
+                    UInt32* bhtab,
+                    Int32   nblock,
+                    Int32   verb )
+{
+   Int32 ftab[257];
+   Int32 ftabCopy[256];
+   Int32 H, i, j, k, l, r, cc, cc1;
+   Int32 nNotDone;
+   Int32 nBhtab;
+   UChar* eclass8 = (UChar*)eclass;
+
+   /*--
+      Initial 1-char radix sort to generate
+      initial fmap and initial BH bits.
+   --*/
+   if (verb >= 4)
+      VPrintf0 ( "        bucket sorting ...\n" );
+   for (i = 0; i < 257;    i++) ftab[i] = 0;
+   for (i = 0; i < nblock; i++) ftab[eclass8[i]]++;
+   for (i = 0; i < 256;    i++) ftabCopy[i] = ftab[i];
+   for (i = 1; i < 257;    i++) ftab[i] += ftab[i-1];
+
+   for (i = 0; i < nblock; i++) {
+      j = eclass8[i];
+      k = ftab[j] - 1;
+      ftab[j] = k;
+      fmap[k] = i;
+   }
+
+   nBhtab = 2 + (nblock / 32);
+   for (i = 0; i < nBhtab; i++) bhtab[i] = 0;
+   for (i = 0; i < 256; i++) SET_BH(ftab[i]);
+
+   /*--
+      Inductively refine the buckets.  Kind-of an
+      "exponential radix sort" (!), inspired by the
+      Manber-Myers suffix array construction algorithm.
+   --*/
+
+   /*-- set sentinel bits for block-end detection --*/
+   for (i = 0; i < 32; i++) { 
+      SET_BH(nblock + 2*i);
+      CLEAR_BH(nblock + 2*i + 1);
+   }
+
+   /*-- the log(N) loop --*/
+   H = 1;
+   while (1) {
+
+      if (verb >= 4) 
+         VPrintf1 ( "        depth %6d has ", H );
+
+      j = 0;
+      for (i = 0; i < nblock; i++) {
+         if (ISSET_BH(i)) j = i;
+         k = fmap[i] - H; if (k < 0) k += nblock;
+         eclass[k] = j;
+      }
+
+      nNotDone = 0;
+      r = -1;
+      while (1) {
+
+	 /*-- find the next non-singleton bucket --*/
+         k = r + 1;
+         while (ISSET_BH(k) && UNALIGNED_BH(k)) k++;
+         if (ISSET_BH(k)) {
+            while (WORD_BH(k) == 0xffffffff) k += 32;
+            while (ISSET_BH(k)) k++;
+         }
+         l = k - 1;
+         if (l >= nblock) break;
+         while (!ISSET_BH(k) && UNALIGNED_BH(k)) k++;
+         if (!ISSET_BH(k)) {
+            while (WORD_BH(k) == 0x00000000) k += 32;
+            while (!ISSET_BH(k)) k++;
+         }
+         r = k - 1;
+         if (r >= nblock) break;
+
+         /*-- now [l, r] bracket current bucket --*/
+         if (r > l) {
+            nNotDone += (r - l + 1);
+            fallbackQSort3 ( fmap, eclass, l, r );
+
+            /*-- scan bucket and generate header bits-- */
+            cc = -1;
+            for (i = l; i <= r; i++) {
+               cc1 = eclass[fmap[i]];
+               if (cc != cc1) { SET_BH(i); cc = cc1; };
+            }
+         }
+      }
+
+      if (verb >= 4) 
+         VPrintf1 ( "%6d unresolved strings\n", nNotDone );
+
+      H *= 2;
+      if (H > nblock || nNotDone == 0) break;
+   }
+
+   /*-- 
+      Reconstruct the original block in
+      eclass8 [0 .. nblock-1], since the
+      previous phase destroyed it.
+   --*/
+   if (verb >= 4)
+      VPrintf0 ( "        reconstructing block ...\n" );
+   j = 0;
+   for (i = 0; i < nblock; i++) {
+      while (ftabCopy[j] == 0) j++;
+      ftabCopy[j]--;
+      eclass8[fmap[i]] = (UChar)j;
+   }
+   AssertH ( j < 256, 1005 );
+}
+
+#undef       SET_BH
+#undef     CLEAR_BH
+#undef     ISSET_BH
+#undef      WORD_BH
+#undef UNALIGNED_BH
+
+
+/*---------------------------------------------*/
+/*--- The main, O(N^2 log(N)) sorting       ---*/
+/*--- algorithm.  Faster for "normal"       ---*/
+/*--- non-repetitive blocks.                ---*/
+/*---------------------------------------------*/
+
+/*---------------------------------------------*/
+static
+__inline__
+Bool mainGtU ( UInt32  i1, 
+               UInt32  i2,
+               UChar*  block, 
+               UInt16* quadrant,
+               UInt32  nblock,
+               Int32*  budget )
+{
+   Int32  k;
+   UChar  c1, c2;
+   UInt16 s1, s2;
+
+   AssertD ( i1 != i2, "mainGtU" );
+   /* 1 */
+   c1 = block[i1]; c2 = block[i2];
+   if (c1 != c2) return (c1 > c2);
+   i1++; i2++;
+   /* 2 */
+   c1 = block[i1]; c2 = block[i2];
+   if (c1 != c2) return (c1 > c2);
+   i1++; i2++;
+   /* 3 */
+   c1 = block[i1]; c2 = block[i2];
+   if (c1 != c2) return (c1 > c2);
+   i1++; i2++;
+   /* 4 */
+   c1 = block[i1]; c2 = block[i2];
+   if (c1 != c2) return (c1 > c2);
+   i1++; i2++;
+   /* 5 */
+   c1 = block[i1]; c2 = block[i2];
+   if (c1 != c2) return (c1 > c2);
+   i1++; i2++;
+   /* 6 */
+   c1 = block[i1]; c2 = block[i2];
+   if (c1 != c2) return (c1 > c2);
+   i1++; i2++;
+   /* 7 */
+   c1 = block[i1]; c2 = block[i2];
+   if (c1 != c2) return (c1 > c2);
+   i1++; i2++;
+   /* 8 */
+   c1 = block[i1]; c2 = block[i2];
+   if (c1 != c2) return (c1 > c2);
+   i1++; i2++;
+   /* 9 */
+   c1 = block[i1]; c2 = block[i2];
+   if (c1 != c2) return (c1 > c2);
+   i1++; i2++;
+   /* 10 */
+   c1 = block[i1]; c2 = block[i2];
+   if (c1 != c2) return (c1 > c2);
+   i1++; i2++;
+   /* 11 */
+   c1 = block[i1]; c2 = block[i2];
+   if (c1 != c2) return (c1 > c2);
+   i1++; i2++;
+   /* 12 */
+   c1 = block[i1]; c2 = block[i2];
+   if (c1 != c2) return (c1 > c2);
+   i1++; i2++;
+
+   k = nblock + 8;
+
+   do {
+      /* 1 */
+      c1 = block[i1]; c2 = block[i2];
+      if (c1 != c2) return (c1 > c2);
+      s1 = quadrant[i1]; s2 = quadrant[i2];
+      if (s1 != s2) return (s1 > s2);
+      i1++; i2++;
+      /* 2 */
+      c1 = block[i1]; c2 = block[i2];
+      if (c1 != c2) return (c1 > c2);
+      s1 = quadrant[i1]; s2 = quadrant[i2];
+      if (s1 != s2) return (s1 > s2);
+      i1++; i2++;
+      /* 3 */
+      c1 = block[i1]; c2 = block[i2];
+      if (c1 != c2) return (c1 > c2);
+      s1 = quadrant[i1]; s2 = quadrant[i2];
+      if (s1 != s2) return (s1 > s2);
+      i1++; i2++;
+      /* 4 */
+      c1 = block[i1]; c2 = block[i2];
+      if (c1 != c2) return (c1 > c2);
+      s1 = quadrant[i1]; s2 = quadrant[i2];
+      if (s1 != s2) return (s1 > s2);
+      i1++; i2++;
+      /* 5 */
+      c1 = block[i1]; c2 = block[i2];
+      if (c1 != c2) return (c1 > c2);
+      s1 = quadrant[i1]; s2 = quadrant[i2];
+      if (s1 != s2) return (s1 > s2);
+      i1++; i2++;
+      /* 6 */
+      c1 = block[i1]; c2 = block[i2];
+      if (c1 != c2) return (c1 > c2);
+      s1 = quadrant[i1]; s2 = quadrant[i2];
+      if (s1 != s2) return (s1 > s2);
+      i1++; i2++;
+      /* 7 */
+      c1 = block[i1]; c2 = block[i2];
+      if (c1 != c2) return (c1 > c2);
+      s1 = quadrant[i1]; s2 = quadrant[i2];
+      if (s1 != s2) return (s1 > s2);
+      i1++; i2++;
+      /* 8 */
+      c1 = block[i1]; c2 = block[i2];
+      if (c1 != c2) return (c1 > c2);
+      s1 = quadrant[i1]; s2 = quadrant[i2];
+      if (s1 != s2) return (s1 > s2);
+      i1++; i2++;
+
+      if (i1 >= nblock) i1 -= nblock;
+      if (i2 >= nblock) i2 -= nblock;
+
+      k -= 8;
+      (*budget)--;
+   }
+      while (k >= 0);
+
+   return False;
+}
+
+
+/*---------------------------------------------*/
+/*--
+   Knuth's increments seem to work better
+   than Incerpi-Sedgewick here.  Possibly
+   because the number of elems to sort is
+   usually small, typically <= 20.
+--*/
+static
+Int32 incs[14] = { 1, 4, 13, 40, 121, 364, 1093, 3280,
+                   9841, 29524, 88573, 265720,
+                   797161, 2391484 };
+
+static
+void mainSimpleSort ( UInt32* ptr,
+                      UChar*  block,
+                      UInt16* quadrant,
+                      Int32   nblock,
+                      Int32   lo, 
+                      Int32   hi, 
+                      Int32   d,
+                      Int32*  budget )
+{
+   Int32 i, j, h, bigN, hp;
+   UInt32 v;
+
+   bigN = hi - lo + 1;
+   if (bigN < 2) return;
+
+   hp = 0;
+   while (incs[hp] < bigN) hp++;
+   hp--;
+
+   for (; hp >= 0; hp--) {
+      h = incs[hp];
+
+      i = lo + h;
+      while (True) {
+
+         /*-- copy 1 --*/
+         if (i > hi) break;
+         v = ptr[i];
+         j = i;
+         while ( mainGtU ( 
+                    ptr[j-h]+d, v+d, block, quadrant, nblock, budget 
+                 ) ) {
+            ptr[j] = ptr[j-h];
+            j = j - h;
+            if (j <= (lo + h - 1)) break;
+         }
+         ptr[j] = v;
+         i++;
+
+         /*-- copy 2 --*/
+         if (i > hi) break;
+         v = ptr[i];
+         j = i;
+         while ( mainGtU ( 
+                    ptr[j-h]+d, v+d, block, quadrant, nblock, budget 
+                 ) ) {
+            ptr[j] = ptr[j-h];
+            j = j - h;
+            if (j <= (lo + h - 1)) break;
+         }
+         ptr[j] = v;
+         i++;
+
+         /*-- copy 3 --*/
+         if (i > hi) break;
+         v = ptr[i];
+         j = i;
+         while ( mainGtU ( 
+                    ptr[j-h]+d, v+d, block, quadrant, nblock, budget 
+                 ) ) {
+            ptr[j] = ptr[j-h];
+            j = j - h;
+            if (j <= (lo + h - 1)) break;
+         }
+         ptr[j] = v;
+         i++;
+
+         if (*budget < 0) return;
+      }
+   }
+}
+
+
+/*---------------------------------------------*/
+/*--
+   The following is an implementation of
+   an elegant 3-way quicksort for strings,
+   described in a paper "Fast Algorithms for
+   Sorting and Searching Strings", by Robert
+   Sedgewick and Jon L. Bentley.
+--*/
+
+#define mswap(zz1, zz2) \
+   { Int32 zztmp = zz1; zz1 = zz2; zz2 = zztmp; }
+
+#define mvswap(zzp1, zzp2, zzn)       \
+{                                     \
+   Int32 yyp1 = (zzp1);               \
+   Int32 yyp2 = (zzp2);               \
+   Int32 yyn  = (zzn);                \
+   while (yyn > 0) {                  \
+      mswap(ptr[yyp1], ptr[yyp2]);    \
+      yyp1++; yyp2++; yyn--;          \
+   }                                  \
+}
+
+static 
+__inline__
+UChar mmed3 ( UChar a, UChar b, UChar c )
+{
+   UChar t;
+   if (a > b) { t = a; a = b; b = t; };
+   if (b > c) { 
+      b = c;
+      if (a > b) b = a;
+   }
+   return b;
+}
+
+#define mmin(a,b) ((a) < (b)) ? (a) : (b)
+
+#define mpush(lz,hz,dz) { stackLo[sp] = lz; \
+                          stackHi[sp] = hz; \
+                          stackD [sp] = dz; \
+                          sp++; }
+
+#define mpop(lz,hz,dz) { sp--;             \
+                         lz = stackLo[sp]; \
+                         hz = stackHi[sp]; \
+                         dz = stackD [sp]; }
+
+
+#define mnextsize(az) (nextHi[az]-nextLo[az])
+
+#define mnextswap(az,bz)                                        \
+   { Int32 tz;                                                  \
+     tz = nextLo[az]; nextLo[az] = nextLo[bz]; nextLo[bz] = tz; \
+     tz = nextHi[az]; nextHi[az] = nextHi[bz]; nextHi[bz] = tz; \
+     tz = nextD [az]; nextD [az] = nextD [bz]; nextD [bz] = tz; }
+
+
+#define MAIN_QSORT_SMALL_THRESH 20
+#define MAIN_QSORT_DEPTH_THRESH (BZ_N_RADIX + BZ_N_QSORT)
+#define MAIN_QSORT_STACK_SIZE 100
+
+static
+void mainQSort3 ( UInt32* ptr,
+                  UChar*  block,
+                  UInt16* quadrant,
+                  Int32   nblock,
+                  Int32   loSt, 
+                  Int32   hiSt, 
+                  Int32   dSt,
+                  Int32*  budget )
+{
+   Int32 unLo, unHi, ltLo, gtHi, n, m, med;
+   Int32 sp, lo, hi, d;
+
+   Int32 stackLo[MAIN_QSORT_STACK_SIZE];
+   Int32 stackHi[MAIN_QSORT_STACK_SIZE];
+   Int32 stackD [MAIN_QSORT_STACK_SIZE];
+
+   Int32 nextLo[3];
+   Int32 nextHi[3];
+   Int32 nextD [3];
+
+   sp = 0;
+   mpush ( loSt, hiSt, dSt );
+
+   while (sp > 0) {
+
+      AssertH ( sp < MAIN_QSORT_STACK_SIZE - 2, 1001 );
+
+      mpop ( lo, hi, d );
+      if (hi - lo < MAIN_QSORT_SMALL_THRESH || 
+          d > MAIN_QSORT_DEPTH_THRESH) {
+         mainSimpleSort ( ptr, block, quadrant, nblock, lo, hi, d, budget );
+         if (*budget < 0) return;
+         continue;
+      }
+
+      med = (Int32) 
+            mmed3 ( block[ptr[ lo         ]+d],
+                    block[ptr[ hi         ]+d],
+                    block[ptr[ (lo+hi)>>1 ]+d] );
+
+      unLo = ltLo = lo;
+      unHi = gtHi = hi;
+
+      while (True) {
+         while (True) {
+            if (unLo > unHi) break;
+            n = ((Int32)block[ptr[unLo]+d]) - med;
+            if (n == 0) { 
+               mswap(ptr[unLo], ptr[ltLo]); 
+               ltLo++; unLo++; continue; 
+            };
+            if (n >  0) break;
+            unLo++;
+         }
+         while (True) {
+            if (unLo > unHi) break;
+            n = ((Int32)block[ptr[unHi]+d]) - med;
+            if (n == 0) { 
+               mswap(ptr[unHi], ptr[gtHi]); 
+               gtHi--; unHi--; continue; 
+            };
+            if (n <  0) break;
+            unHi--;
+         }
+         if (unLo > unHi) break;
+         mswap(ptr[unLo], ptr[unHi]); unLo++; unHi--;
+      }
+
+      AssertD ( unHi == unLo-1, "mainQSort3(2)" );
+
+      if (gtHi < ltLo) {
+         mpush(lo, hi, d+1 );
+         continue;
+      }
+
+      n = mmin(ltLo-lo, unLo-ltLo); mvswap(lo, unLo-n, n);
+      m = mmin(hi-gtHi, gtHi-unHi); mvswap(unLo, hi-m+1, m);
+
+      n = lo + unLo - ltLo - 1;
+      m = hi - (gtHi - unHi) + 1;
+
+      nextLo[0] = lo;  nextHi[0] = n;   nextD[0] = d;
+      nextLo[1] = m;   nextHi[1] = hi;  nextD[1] = d;
+      nextLo[2] = n+1; nextHi[2] = m-1; nextD[2] = d+1;
+
+      if (mnextsize(0) < mnextsize(1)) mnextswap(0,1);
+      if (mnextsize(1) < mnextsize(2)) mnextswap(1,2);
+      if (mnextsize(0) < mnextsize(1)) mnextswap(0,1);
+
+      AssertD (mnextsize(0) >= mnextsize(1), "mainQSort3(8)" );
+      AssertD (mnextsize(1) >= mnextsize(2), "mainQSort3(9)" );
+
+      mpush (nextLo[0], nextHi[0], nextD[0]);
+      mpush (nextLo[1], nextHi[1], nextD[1]);
+      mpush (nextLo[2], nextHi[2], nextD[2]);
+   }
+}
+
+#undef mswap
+#undef mvswap
+#undef mpush
+#undef mpop
+#undef mmin
+#undef mnextsize
+#undef mnextswap
+#undef MAIN_QSORT_SMALL_THRESH
+#undef MAIN_QSORT_DEPTH_THRESH
+#undef MAIN_QSORT_STACK_SIZE
+
+
+/*---------------------------------------------*/
+/* Pre:
+      nblock > N_OVERSHOOT
+      block32 exists for [0 .. nblock-1 +N_OVERSHOOT]
+      ((UChar*)block32) [0 .. nblock-1] holds block
+      ptr exists for [0 .. nblock-1]
+
+   Post:
+      ((UChar*)block32) [0 .. nblock-1] holds block
+      All other areas of block32 destroyed
+      ftab [0 .. 65536 ] destroyed
+      ptr [0 .. nblock-1] holds sorted order
+      if (*budget < 0), sorting was abandoned
+*/
+
+#define BIGFREQ(b) (ftab[((b)+1) << 8] - ftab[(b) << 8])
+#define SETMASK (1 << 21)
+#define CLEARMASK (~(SETMASK))
+
+static
+void mainSort ( UInt32* ptr, 
+                UChar*  block,
+                UInt16* quadrant, 
+                UInt32* ftab,
+                Int32   nblock,
+                Int32   verb,
+                Int32*  budget )
+{
+   Int32  i, j, k, ss, sb;
+   Int32  runningOrder[256];
+   Bool   bigDone[256];
+   Int32  copyStart[256];
+   Int32  copyEnd  [256];
+   UChar  c1;
+   Int32  numQSorted;
+   UInt16 s;
+   if (verb >= 4) VPrintf0 ( "        main sort initialise ...\n" );
+
+   /*-- set up the 2-byte frequency table --*/
+   for (i = 65536; i >= 0; i--) ftab[i] = 0;
+
+   j = block[0] << 8;
+   i = nblock-1;
+   for (; i >= 3; i -= 4) {
+      quadrant[i] = 0;
+      j = (j >> 8) | ( ((UInt16)block[i]) << 8);
+      ftab[j]++;
+      quadrant[i-1] = 0;
+      j = (j >> 8) | ( ((UInt16)block[i-1]) << 8);
+      ftab[j]++;
+      quadrant[i-2] = 0;
+      j = (j >> 8) | ( ((UInt16)block[i-2]) << 8);
+      ftab[j]++;
+      quadrant[i-3] = 0;
+      j = (j >> 8) | ( ((UInt16)block[i-3]) << 8);
+      ftab[j]++;
+   }
+   for (; i >= 0; i--) {
+      quadrant[i] = 0;
+      j = (j >> 8) | ( ((UInt16)block[i]) << 8);
+      ftab[j]++;
+   }
+
+   /*-- (emphasises close relationship of block & quadrant) --*/
+   for (i = 0; i < BZ_N_OVERSHOOT; i++) {
+      block   [nblock+i] = block[i];
+      quadrant[nblock+i] = 0;
+   }
+
+   if (verb >= 4) VPrintf0 ( "        bucket sorting ...\n" );
+
+   /*-- Complete the initial radix sort --*/
+   for (i = 1; i <= 65536; i++) ftab[i] += ftab[i-1];
+
+   s = block[0] << 8;
+   i = nblock-1;
+   for (; i >= 3; i -= 4) {
+      s = (s >> 8) | (block[i] << 8);
+      j = ftab[s] -1;
+      ftab[s] = j;
+      ptr[j] = i;
+      s = (s >> 8) | (block[i-1] << 8);
+      j = ftab[s] -1;
+      ftab[s] = j;
+      ptr[j] = i-1;
+      s = (s >> 8) | (block[i-2] << 8);
+      j = ftab[s] -1;
+      ftab[s] = j;
+      ptr[j] = i-2;
+      s = (s >> 8) | (block[i-3] << 8);
+      j = ftab[s] -1;
+      ftab[s] = j;
+      ptr[j] = i-3;
+   }
+   for (; i >= 0; i--) {
+      s = (s >> 8) | (block[i] << 8);
+      j = ftab[s] -1;
+      ftab[s] = j;
+      ptr[j] = i;
+   }
+
+   /*--
+      Now ftab contains the first loc of every small bucket.
+      Calculate the running order, from smallest to largest
+      big bucket.
+   --*/
+   for (i = 0; i <= 255; i++) {
+      bigDone     [i] = False;
+      runningOrder[i] = i;
+   }
+
+   {
+      Int32 vv;
+      Int32 h = 1;
+      do h = 3 * h + 1; while (h <= 256);
+      do {
+         h = h / 3;
+         for (i = h; i <= 255; i++) {
+            vv = runningOrder[i];
+            j = i;
+            while ( BIGFREQ(runningOrder[j-h]) > BIGFREQ(vv) ) {
+               runningOrder[j] = runningOrder[j-h];
+               j = j - h;
+               if (j <= (h - 1)) goto zero;
+            }
+            zero:
+            runningOrder[j] = vv;
+         }
+      } while (h != 1);
+   }
+
+   /*--
+      The main sorting loop.
+   --*/
+
+   numQSorted = 0;
+
+   for (i = 0; i <= 255; i++) {
+
+      /*--
+         Process big buckets, starting with the least full.
+         Basically this is a 3-step process in which we call
+         mainQSort3 to sort the small buckets [ss, j], but
+         also make a big effort to avoid the calls if we can.
+      --*/
+      ss = runningOrder[i];
+
+      /*--
+         Step 1:
+         Complete the big bucket [ss] by quicksorting
+         any unsorted small buckets [ss, j], for j != ss.  
+         Hopefully previous pointer-scanning phases have already
+         completed many of the small buckets [ss, j], so
+         we don't have to sort them at all.
+      --*/
+      for (j = 0; j <= 255; j++) {
+         if (j != ss) {
+            sb = (ss << 8) + j;
+            if ( ! (ftab[sb] & SETMASK) ) {
+               Int32 lo = ftab[sb]   & CLEARMASK;
+               Int32 hi = (ftab[sb+1] & CLEARMASK) - 1;
+               if (hi > lo) {
+                  if (verb >= 4)
+                     VPrintf4 ( "        qsort [0x%x, 0x%x]   "
+                                "done %d   this %d\n",
+                                ss, j, numQSorted, hi - lo + 1 );
+                  mainQSort3 ( 
+                     ptr, block, quadrant, nblock, 
+                     lo, hi, BZ_N_RADIX, budget 
+                  );   
+                  numQSorted += (hi - lo + 1);
+                  if (*budget < 0) return;
+               }
+            }
+            ftab[sb] |= SETMASK;
+         }
+      }
+
+      AssertH ( !bigDone[ss], 1006 );
+
+      /*--
+         Step 2:
+         Now scan this big bucket [ss] so as to synthesise the
+         sorted order for small buckets [t, ss] for all t,
+         including, magically, the bucket [ss,ss] too.
+         This will avoid doing Real Work in subsequent Step 1's.
+      --*/
+      {
+         for (j = 0; j <= 255; j++) {
+            copyStart[j] =  ftab[(j << 8) + ss]     & CLEARMASK;
+            copyEnd  [j] = (ftab[(j << 8) + ss + 1] & CLEARMASK) - 1;
+         }
+         for (j = ftab[ss << 8] & CLEARMASK; j < copyStart[ss]; j++) {
+            k = ptr[j]-1; if (k < 0) k += nblock;
+            c1 = block[k];
+            if (!bigDone[c1])
+               ptr[ copyStart[c1]++ ] = k;
+         }
+         for (j = (ftab[(ss+1) << 8] & CLEARMASK) - 1; j > copyEnd[ss]; j--) {
+            k = ptr[j]-1; if (k < 0) k += nblock;
+            c1 = block[k];
+            if (!bigDone[c1]) 
+               ptr[ copyEnd[c1]-- ] = k;
+         }
+      }
+
+      AssertH ( (copyStart[ss]-1 == copyEnd[ss])
+                || 
+                /* Extremely rare case missing in bzip2-1.0.0 and 1.0.1.
+                   Necessity for this case is demonstrated by compressing 
+                   a sequence of approximately 48.5 million of character 
+                   251; 1.0.0/1.0.1 will then die here. */
+                (copyStart[ss] == 0 && copyEnd[ss] == nblock-1),
+                1007 )
+
+      for (j = 0; j <= 255; j++) ftab[(j << 8) + ss] |= SETMASK;
+
+      /*--
+         Step 3:
+         The [ss] big bucket is now done.  Record this fact,
+         and update the quadrant descriptors.  Remember to
+         update quadrants in the overshoot area too, if
+         necessary.  The "if (i < 255)" test merely skips
+         this updating for the last bucket processed, since
+         updating for the last bucket is pointless.
+
+         The quadrant array provides a way to incrementally
+         cache sort orderings, as they appear, so as to 
+         make subsequent comparisons in fullGtU() complete
+         faster.  For repetitive blocks this makes a big
+         difference (but not big enough to be able to avoid
+         the fallback sorting mechanism, exponential radix sort).
+
+         The precise meaning is: at all times:
+
+            for 0 <= i < nblock and 0 <= j <= nblock
+
+            if block[i] != block[j], 
+
+               then the relative values of quadrant[i] and 
+                    quadrant[j] are meaningless.
+
+               else {
+                  if quadrant[i] < quadrant[j]
+                     then the string starting at i lexicographically
+                     precedes the string starting at j
+
+                  else if quadrant[i] > quadrant[j]
+                     then the string starting at j lexicographically
+                     precedes the string starting at i
+
+                  else
+                     the relative ordering of the strings starting
+                     at i and j has not yet been determined.
+               }
+      --*/
+      bigDone[ss] = True;
+
+      if (i < 255) {
+         Int32 bbStart  = ftab[ss << 8] & CLEARMASK;
+         Int32 bbSize   = (ftab[(ss+1) << 8] & CLEARMASK) - bbStart;
+         Int32 shifts   = 0;
+
+         while ((bbSize >> shifts) > 65534) shifts++;
+
+         for (j = bbSize-1; j >= 0; j--) {
+            Int32 a2update     = ptr[bbStart + j];
+            UInt16 qVal        = (UInt16)(j >> shifts);
+            quadrant[a2update] = qVal;
+            if (a2update < BZ_N_OVERSHOOT)
+               quadrant[a2update + nblock] = qVal;
+         }
+         AssertH ( ((bbSize-1) >> shifts) <= 65535, 1002 );
+      }
+
+   }
+
+   if (verb >= 4)
+      VPrintf3 ( "        %d pointers, %d sorted, %d scanned\n",
+                 nblock, numQSorted, nblock - numQSorted );
+}
+
+#undef BIGFREQ
+#undef SETMASK
+#undef CLEARMASK
+
+
+/*---------------------------------------------*/
+/* Pre:
+      nblock > 0
+      arr2 exists for [0 .. nblock-1 +N_OVERSHOOT]
+      ((UChar*)arr2)  [0 .. nblock-1] holds block
+      arr1 exists for [0 .. nblock-1]
+
+   Post:
+      ((UChar*)arr2) [0 .. nblock-1] holds block
+      All other areas of block destroyed
+      ftab [ 0 .. 65536 ] destroyed
+      arr1 [0 .. nblock-1] holds sorted order
+*/
+void BZ2_blockSort ( EState* s )
+{
+   UInt32* ptr    = s->ptr; 
+   UChar*  block  = s->block;
+   UInt32* ftab   = s->ftab;
+   Int32   nblock = s->nblock;
+   Int32   verb   = s->verbosity;
+   Int32   wfact  = s->workFactor;
+   UInt16* quadrant;
+   Int32   budget;
+   Int32   budgetInit;
+   Int32   i;
+
+   if (nblock < 10000) {
+      fallbackSort ( s->arr1, s->arr2, ftab, nblock, verb );
+   } else {
+      /* Calculate the location for quadrant, remembering to get
+         the alignment right.  Assumes that &(block[0]) is at least
+         2-byte aligned -- this should be ok since block is really
+         the first section of arr2.
+      */
+      i = nblock+BZ_N_OVERSHOOT;
+      if (i & 1) i++;
+      quadrant = (UInt16*)(&(block[i]));
+
+      /* (wfact-1) / 3 puts the default-factor-30
+         transition point at very roughly the same place as 
+         with v0.1 and v0.9.0.  
+         Not that it particularly matters any more, since the
+         resulting compressed stream is now the same regardless
+         of whether or not we use the main sort or fallback sort.
+      */
+      if (wfact < 1  ) wfact = 1;
+      if (wfact > 100) wfact = 100;
+      budgetInit = nblock * ((wfact-1) / 3);
+      budget = budgetInit;
+
+      mainSort ( ptr, block, quadrant, ftab, nblock, verb, &budget );
+      if (verb >= 3) 
+         VPrintf3 ( "      %d work, %d block, ratio %5.2f\n",
+                    budgetInit - budget,
+                    nblock, 
+                    (float)(budgetInit - budget) /
+                    (float)(nblock==0 ? 1 : nblock) ); 
+      if (budget < 0) {
+         if (verb >= 2) 
+            VPrintf0 ( "    too repetitive; using fallback"
+                       " sorting algorithm\n" );
+         fallbackSort ( s->arr1, s->arr2, ftab, nblock, verb );
+      }
+   }
+
+   s->origPtr = -1;
+   for (i = 0; i < s->nblock; i++)
+      if (ptr[i] == 0)
+         { s->origPtr = i; break; };
+
+   AssertH( s->origPtr != -1, 1003 );
+}
+
+
+/*-------------------------------------------------------------*/
+/*--- end                                       blocksort.c ---*/
+/*-------------------------------------------------------------*/
diff --git a/cbits/bzlib.c b/cbits/bzlib.c
new file mode 100644
--- /dev/null
+++ b/cbits/bzlib.c
@@ -0,0 +1,1572 @@
+
+/*-------------------------------------------------------------*/
+/*--- Library top-level functions.                          ---*/
+/*---                                               bzlib.c ---*/
+/*-------------------------------------------------------------*/
+
+/* ------------------------------------------------------------------
+   This file is part of bzip2/libbzip2, a program and library for
+   lossless, block-sorting data compression.
+
+   bzip2/libbzip2 version 1.0.8 of 13 July 2019
+   Copyright (C) 1996-2019 Julian Seward <jseward@acm.org>
+
+   Please read the WARNING, DISCLAIMER and PATENTS sections in the 
+   README file.
+
+   This program is released under the terms of the license contained
+   in the file LICENSE.
+   ------------------------------------------------------------------ */
+
+/* CHANGES
+   0.9.0    -- original version.
+   0.9.0a/b -- no changes in this file.
+   0.9.0c   -- made zero-length BZ_FLUSH work correctly in bzCompress().
+     fixed bzWrite/bzRead to ignore zero-length requests.
+     fixed bzread to correctly handle read requests after EOF.
+     wrong parameter order in call to bzDecompressInit in
+     bzBuffToBuffDecompress.  Fixed.
+*/
+
+#include "bzlib_private.h"
+
+
+/*---------------------------------------------------*/
+/*--- Compression stuff                           ---*/
+/*---------------------------------------------------*/
+
+
+/*---------------------------------------------------*/
+#ifndef BZ_NO_STDIO
+void BZ2_bz__AssertH__fail ( int errcode )
+{
+   fprintf(stderr, 
+      "\n\nbzip2/libbzip2: internal error number %d.\n"
+      "This is a bug in bzip2/libbzip2, %s.\n"
+      "Please report it to: bzip2-devel@sourceware.org.  If this happened\n"
+      "when you were using some program which uses libbzip2 as a\n"
+      "component, you should also report this bug to the author(s)\n"
+      "of that program.  Please make an effort to report this bug;\n"
+      "timely and accurate bug reports eventually lead to higher\n"
+      "quality software.  Thanks.\n\n",
+      errcode,
+      BZ2_bzlibVersion()
+   );
+
+   if (errcode == 1007) {
+   fprintf(stderr,
+      "\n*** A special note about internal error number 1007 ***\n"
+      "\n"
+      "Experience suggests that a common cause of i.e. 1007\n"
+      "is unreliable memory or other hardware.  The 1007 assertion\n"
+      "just happens to cross-check the results of huge numbers of\n"
+      "memory reads/writes, and so acts (unintendedly) as a stress\n"
+      "test of your memory system.\n"
+      "\n"
+      "I suggest the following: try compressing the file again,\n"
+      "possibly monitoring progress in detail with the -vv flag.\n"
+      "\n"
+      "* If the error cannot be reproduced, and/or happens at different\n"
+      "  points in compression, you may have a flaky memory system.\n"
+      "  Try a memory-test program.  I have used Memtest86\n"
+      "  (www.memtest86.com).  At the time of writing it is free (GPLd).\n"
+      "  Memtest86 tests memory much more thorougly than your BIOSs\n"
+      "  power-on test, and may find failures that the BIOS doesn't.\n"
+      "\n"
+      "* If the error can be repeatably reproduced, this is a bug in\n"
+      "  bzip2, and I would very much like to hear about it.  Please\n"
+      "  let me know, and, ideally, save a copy of the file causing the\n"
+      "  problem -- without which I will be unable to investigate it.\n"
+      "\n"
+   );
+   }
+
+   exit(3);
+}
+#endif
+
+
+/*---------------------------------------------------*/
+static
+int bz_config_ok ( void )
+{
+   if (sizeof(int)   != 4) return 0;
+   if (sizeof(short) != 2) return 0;
+   if (sizeof(char)  != 1) return 0;
+   return 1;
+}
+
+
+/*---------------------------------------------------*/
+static
+void* default_bzalloc ( void* opaque, Int32 items, Int32 size )
+{
+   void* v = malloc ( items * size );
+   return v;
+}
+
+static
+void default_bzfree ( void* opaque, void* addr )
+{
+   if (addr != NULL) free ( addr );
+}
+
+
+/*---------------------------------------------------*/
+static
+void prepare_new_block ( EState* s )
+{
+   Int32 i;
+   s->nblock = 0;
+   s->numZ = 0;
+   s->state_out_pos = 0;
+   BZ_INITIALISE_CRC ( s->blockCRC );
+   for (i = 0; i < 256; i++) s->inUse[i] = False;
+   s->blockNo++;
+}
+
+
+/*---------------------------------------------------*/
+static
+void init_RL ( EState* s )
+{
+   s->state_in_ch  = 256;
+   s->state_in_len = 0;
+}
+
+
+static
+Bool isempty_RL ( EState* s )
+{
+   if (s->state_in_ch < 256 && s->state_in_len > 0)
+      return False; else
+      return True;
+}
+
+
+/*---------------------------------------------------*/
+int BZ_API(BZ2_bzCompressInit) 
+                    ( bz_stream* strm, 
+                     int        blockSize100k,
+                     int        verbosity,
+                     int        workFactor )
+{
+   Int32   n;
+   EState* s;
+
+   if (!bz_config_ok()) return BZ_CONFIG_ERROR;
+
+   if (strm == NULL || 
+       blockSize100k < 1 || blockSize100k > 9 ||
+       workFactor < 0 || workFactor > 250)
+     return BZ_PARAM_ERROR;
+
+   if (workFactor == 0) workFactor = 30;
+   if (strm->bzalloc == NULL) strm->bzalloc = default_bzalloc;
+   if (strm->bzfree == NULL) strm->bzfree = default_bzfree;
+
+   s = BZALLOC( sizeof(EState) );
+   if (s == NULL) return BZ_MEM_ERROR;
+   s->strm = strm;
+
+   s->arr1 = NULL;
+   s->arr2 = NULL;
+   s->ftab = NULL;
+
+   n       = 100000 * blockSize100k;
+   s->arr1 = BZALLOC( n                  * sizeof(UInt32) );
+   s->arr2 = BZALLOC( (n+BZ_N_OVERSHOOT) * sizeof(UInt32) );
+   s->ftab = BZALLOC( 65537              * sizeof(UInt32) );
+
+   if (s->arr1 == NULL || s->arr2 == NULL || s->ftab == NULL) {
+      if (s->arr1 != NULL) BZFREE(s->arr1);
+      if (s->arr2 != NULL) BZFREE(s->arr2);
+      if (s->ftab != NULL) BZFREE(s->ftab);
+      if (s       != NULL) BZFREE(s);
+      return BZ_MEM_ERROR;
+   }
+
+   s->blockNo           = 0;
+   s->state             = BZ_S_INPUT;
+   s->mode              = BZ_M_RUNNING;
+   s->combinedCRC       = 0;
+   s->blockSize100k     = blockSize100k;
+   s->nblockMAX         = 100000 * blockSize100k - 19;
+   s->verbosity         = verbosity;
+   s->workFactor        = workFactor;
+
+   s->block             = (UChar*)s->arr2;
+   s->mtfv              = (UInt16*)s->arr1;
+   s->zbits             = NULL;
+   s->ptr               = (UInt32*)s->arr1;
+
+   strm->state          = s;
+   strm->total_in_lo32  = 0;
+   strm->total_in_hi32  = 0;
+   strm->total_out_lo32 = 0;
+   strm->total_out_hi32 = 0;
+   init_RL ( s );
+   prepare_new_block ( s );
+   return BZ_OK;
+}
+
+
+/*---------------------------------------------------*/
+static
+void add_pair_to_block ( EState* s )
+{
+   Int32 i;
+   UChar ch = (UChar)(s->state_in_ch);
+   for (i = 0; i < s->state_in_len; i++) {
+      BZ_UPDATE_CRC( s->blockCRC, ch );
+   }
+   s->inUse[s->state_in_ch] = True;
+   switch (s->state_in_len) {
+      case 1:
+         s->block[s->nblock] = (UChar)ch; s->nblock++;
+         break;
+      case 2:
+         s->block[s->nblock] = (UChar)ch; s->nblock++;
+         s->block[s->nblock] = (UChar)ch; s->nblock++;
+         break;
+      case 3:
+         s->block[s->nblock] = (UChar)ch; s->nblock++;
+         s->block[s->nblock] = (UChar)ch; s->nblock++;
+         s->block[s->nblock] = (UChar)ch; s->nblock++;
+         break;
+      default:
+         s->inUse[s->state_in_len-4] = True;
+         s->block[s->nblock] = (UChar)ch; s->nblock++;
+         s->block[s->nblock] = (UChar)ch; s->nblock++;
+         s->block[s->nblock] = (UChar)ch; s->nblock++;
+         s->block[s->nblock] = (UChar)ch; s->nblock++;
+         s->block[s->nblock] = ((UChar)(s->state_in_len-4));
+         s->nblock++;
+         break;
+   }
+}
+
+
+/*---------------------------------------------------*/
+static
+void flush_RL ( EState* s )
+{
+   if (s->state_in_ch < 256) add_pair_to_block ( s );
+   init_RL ( s );
+}
+
+
+/*---------------------------------------------------*/
+#define ADD_CHAR_TO_BLOCK(zs,zchh0)               \
+{                                                 \
+   UInt32 zchh = (UInt32)(zchh0);                 \
+   /*-- fast track the common case --*/           \
+   if (zchh != zs->state_in_ch &&                 \
+       zs->state_in_len == 1) {                   \
+      UChar ch = (UChar)(zs->state_in_ch);        \
+      BZ_UPDATE_CRC( zs->blockCRC, ch );          \
+      zs->inUse[zs->state_in_ch] = True;          \
+      zs->block[zs->nblock] = (UChar)ch;          \
+      zs->nblock++;                               \
+      zs->state_in_ch = zchh;                     \
+   }                                              \
+   else                                           \
+   /*-- general, uncommon cases --*/              \
+   if (zchh != zs->state_in_ch ||                 \
+      zs->state_in_len == 255) {                  \
+      if (zs->state_in_ch < 256)                  \
+         add_pair_to_block ( zs );                \
+      zs->state_in_ch = zchh;                     \
+      zs->state_in_len = 1;                       \
+   } else {                                       \
+      zs->state_in_len++;                         \
+   }                                              \
+}
+
+
+/*---------------------------------------------------*/
+static
+Bool copy_input_until_stop ( EState* s )
+{
+   Bool progress_in = False;
+
+   if (s->mode == BZ_M_RUNNING) {
+
+      /*-- fast track the common case --*/
+      while (True) {
+         /*-- block full? --*/
+         if (s->nblock >= s->nblockMAX) break;
+         /*-- no input? --*/
+         if (s->strm->avail_in == 0) break;
+         progress_in = True;
+         ADD_CHAR_TO_BLOCK ( s, (UInt32)(*((UChar*)(s->strm->next_in))) ); 
+         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++;
+      }
+
+   } else {
+
+      /*-- general, uncommon case --*/
+      while (True) {
+         /*-- block full? --*/
+         if (s->nblock >= s->nblockMAX) break;
+         /*-- no input? --*/
+         if (s->strm->avail_in == 0) break;
+         /*-- flush/finish end? --*/
+         if (s->avail_in_expect == 0) break;
+         progress_in = True;
+         ADD_CHAR_TO_BLOCK ( s, (UInt32)(*((UChar*)(s->strm->next_in))) ); 
+         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++;
+         s->avail_in_expect--;
+      }
+   }
+   return progress_in;
+}
+
+
+/*---------------------------------------------------*/
+static
+Bool copy_output_until_stop ( EState* s )
+{
+   Bool progress_out = False;
+
+   while (True) {
+
+      /*-- no output space? --*/
+      if (s->strm->avail_out == 0) break;
+
+      /*-- block done? --*/
+      if (s->state_out_pos >= s->numZ) break;
+
+      progress_out = True;
+      *(s->strm->next_out) = s->zbits[s->state_out_pos];
+      s->state_out_pos++;
+      s->strm->avail_out--;
+      s->strm->next_out++;
+      s->strm->total_out_lo32++;
+      if (s->strm->total_out_lo32 == 0) s->strm->total_out_hi32++;
+   }
+
+   return progress_out;
+}
+
+
+/*---------------------------------------------------*/
+static
+Bool handle_compress ( bz_stream* strm )
+{
+   Bool progress_in  = False;
+   Bool progress_out = False;
+   EState* s = strm->state;
+   
+   while (True) {
+
+      if (s->state == BZ_S_OUTPUT) {
+         progress_out |= copy_output_until_stop ( s );
+         if (s->state_out_pos < s->numZ) break;
+         if (s->mode == BZ_M_FINISHING && 
+             s->avail_in_expect == 0 &&
+             isempty_RL(s)) break;
+         prepare_new_block ( s );
+         s->state = BZ_S_INPUT;
+         if (s->mode == BZ_M_FLUSHING && 
+             s->avail_in_expect == 0 &&
+             isempty_RL(s)) break;
+      }
+
+      if (s->state == BZ_S_INPUT) {
+         progress_in |= copy_input_until_stop ( s );
+         if (s->mode != BZ_M_RUNNING && s->avail_in_expect == 0) {
+            flush_RL ( s );
+            BZ2_compressBlock ( s, (Bool)(s->mode == BZ_M_FINISHING) );
+            s->state = BZ_S_OUTPUT;
+         }
+         else
+         if (s->nblock >= s->nblockMAX) {
+            BZ2_compressBlock ( s, False );
+            s->state = BZ_S_OUTPUT;
+         }
+         else
+         if (s->strm->avail_in == 0) {
+            break;
+         }
+      }
+
+   }
+
+   return progress_in || progress_out;
+}
+
+
+/*---------------------------------------------------*/
+int BZ_API(BZ2_bzCompress) ( bz_stream *strm, int action )
+{
+   Bool progress;
+   EState* s;
+   if (strm == NULL) return BZ_PARAM_ERROR;
+   s = strm->state;
+   if (s == NULL) return BZ_PARAM_ERROR;
+   if (s->strm != strm) return BZ_PARAM_ERROR;
+
+   preswitch:
+   switch (s->mode) {
+
+      case BZ_M_IDLE:
+         return BZ_SEQUENCE_ERROR;
+
+      case BZ_M_RUNNING:
+         if (action == BZ_RUN) {
+            progress = handle_compress ( strm );
+            return progress ? BZ_RUN_OK : BZ_PARAM_ERROR;
+         } 
+         else
+	 if (action == BZ_FLUSH) {
+            s->avail_in_expect = strm->avail_in;
+            s->mode = BZ_M_FLUSHING;
+            goto preswitch;
+         }
+         else
+         if (action == BZ_FINISH) {
+            s->avail_in_expect = strm->avail_in;
+            s->mode = BZ_M_FINISHING;
+            goto preswitch;
+         }
+         else 
+            return BZ_PARAM_ERROR;
+
+      case BZ_M_FLUSHING:
+         if (action != BZ_FLUSH) return BZ_SEQUENCE_ERROR;
+         if (s->avail_in_expect != s->strm->avail_in) 
+            return BZ_SEQUENCE_ERROR;
+         progress = handle_compress ( strm );
+         if (s->avail_in_expect > 0 || !isempty_RL(s) ||
+             s->state_out_pos < s->numZ) return BZ_FLUSH_OK;
+         s->mode = BZ_M_RUNNING;
+         return BZ_RUN_OK;
+
+      case BZ_M_FINISHING:
+         if (action != BZ_FINISH) return BZ_SEQUENCE_ERROR;
+         if (s->avail_in_expect != s->strm->avail_in) 
+            return BZ_SEQUENCE_ERROR;
+         progress = handle_compress ( strm );
+         if (!progress) return BZ_SEQUENCE_ERROR;
+         if (s->avail_in_expect > 0 || !isempty_RL(s) ||
+             s->state_out_pos < s->numZ) return BZ_FINISH_OK;
+         s->mode = BZ_M_IDLE;
+         return BZ_STREAM_END;
+   }
+   return BZ_OK; /*--not reached--*/
+}
+
+
+/*---------------------------------------------------*/
+int BZ_API(BZ2_bzCompressEnd)  ( bz_stream *strm )
+{
+   EState* s;
+   if (strm == NULL) return BZ_PARAM_ERROR;
+   s = strm->state;
+   if (s == NULL) return BZ_PARAM_ERROR;
+   if (s->strm != strm) return BZ_PARAM_ERROR;
+
+   if (s->arr1 != NULL) BZFREE(s->arr1);
+   if (s->arr2 != NULL) BZFREE(s->arr2);
+   if (s->ftab != NULL) BZFREE(s->ftab);
+   BZFREE(strm->state);
+
+   strm->state = NULL;   
+
+   return BZ_OK;
+}
+
+
+/*---------------------------------------------------*/
+/*--- Decompression stuff                         ---*/
+/*---------------------------------------------------*/
+
+/*---------------------------------------------------*/
+int BZ_API(BZ2_bzDecompressInit) 
+                     ( bz_stream* strm, 
+                       int        verbosity,
+                       int        small )
+{
+   DState* s;
+
+   if (!bz_config_ok()) return BZ_CONFIG_ERROR;
+
+   if (strm == NULL) return BZ_PARAM_ERROR;
+   if (small != 0 && small != 1) return BZ_PARAM_ERROR;
+   if (verbosity < 0 || verbosity > 4) return BZ_PARAM_ERROR;
+
+   if (strm->bzalloc == NULL) strm->bzalloc = default_bzalloc;
+   if (strm->bzfree == NULL) strm->bzfree = default_bzfree;
+
+   s = BZALLOC( sizeof(DState) );
+   if (s == NULL) return BZ_MEM_ERROR;
+   s->strm                  = strm;
+   strm->state              = s;
+   s->state                 = BZ_X_MAGIC_1;
+   s->bsLive                = 0;
+   s->bsBuff                = 0;
+   s->calculatedCombinedCRC = 0;
+   strm->total_in_lo32      = 0;
+   strm->total_in_hi32      = 0;
+   strm->total_out_lo32     = 0;
+   strm->total_out_hi32     = 0;
+   s->smallDecompress       = (Bool)small;
+   s->ll4                   = NULL;
+   s->ll16                  = NULL;
+   s->tt                    = NULL;
+   s->currBlockNo           = 0;
+   s->verbosity             = verbosity;
+
+   return BZ_OK;
+}
+
+
+/*---------------------------------------------------*/
+/* Return  True iff data corruption is discovered.
+   Returns False if there is no problem.
+*/
+static
+Bool unRLE_obuf_to_output_FAST ( DState* s )
+{
+   UChar k1;
+
+   if (s->blockRandomised) {
+
+      while (True) {
+         /* try to finish existing run */
+         while (True) {
+            if (s->strm->avail_out == 0) return False;
+            if (s->state_out_len == 0) break;
+            *( (UChar*)(s->strm->next_out) ) = s->state_out_ch;
+            BZ_UPDATE_CRC ( s->calculatedBlockCRC, s->state_out_ch );
+            s->state_out_len--;
+            s->strm->next_out++;
+            s->strm->avail_out--;
+            s->strm->total_out_lo32++;
+            if (s->strm->total_out_lo32 == 0) s->strm->total_out_hi32++;
+         }
+
+         /* can a new run be started? */
+         if (s->nblock_used == s->save_nblock+1) return False;
+               
+         /* Only caused by corrupt data stream? */
+         if (s->nblock_used > s->save_nblock+1)
+            return True;
+   
+         s->state_out_len = 1;
+         s->state_out_ch = s->k0;
+         BZ_GET_FAST(k1); BZ_RAND_UPD_MASK; 
+         k1 ^= BZ_RAND_MASK; s->nblock_used++;
+         if (s->nblock_used == s->save_nblock+1) continue;
+         if (k1 != s->k0) { s->k0 = k1; continue; };
+   
+         s->state_out_len = 2;
+         BZ_GET_FAST(k1); BZ_RAND_UPD_MASK; 
+         k1 ^= BZ_RAND_MASK; s->nblock_used++;
+         if (s->nblock_used == s->save_nblock+1) continue;
+         if (k1 != s->k0) { s->k0 = k1; continue; };
+   
+         s->state_out_len = 3;
+         BZ_GET_FAST(k1); BZ_RAND_UPD_MASK; 
+         k1 ^= BZ_RAND_MASK; s->nblock_used++;
+         if (s->nblock_used == s->save_nblock+1) continue;
+         if (k1 != s->k0) { s->k0 = k1; continue; };
+   
+         BZ_GET_FAST(k1); BZ_RAND_UPD_MASK; 
+         k1 ^= BZ_RAND_MASK; s->nblock_used++;
+         s->state_out_len = ((Int32)k1) + 4;
+         BZ_GET_FAST(s->k0); BZ_RAND_UPD_MASK; 
+         s->k0 ^= BZ_RAND_MASK; s->nblock_used++;
+      }
+
+   } else {
+
+      /* restore */
+      UInt32        c_calculatedBlockCRC = s->calculatedBlockCRC;
+      UChar         c_state_out_ch       = s->state_out_ch;
+      Int32         c_state_out_len      = s->state_out_len;
+      Int32         c_nblock_used        = s->nblock_used;
+      Int32         c_k0                 = s->k0;
+      UInt32*       c_tt                 = s->tt;
+      UInt32        c_tPos               = s->tPos;
+      char*         cs_next_out          = s->strm->next_out;
+      unsigned int  cs_avail_out         = s->strm->avail_out;
+      Int32         ro_blockSize100k     = s->blockSize100k;
+      /* end restore */
+
+      UInt32       avail_out_INIT = cs_avail_out;
+      Int32        s_save_nblockPP = s->save_nblock+1;
+      unsigned int total_out_lo32_old;
+
+      while (True) {
+
+         /* try to finish existing run */
+         if (c_state_out_len > 0) {
+            while (True) {
+               if (cs_avail_out == 0) goto return_notr;
+               if (c_state_out_len == 1) break;
+               *( (UChar*)(cs_next_out) ) = c_state_out_ch;
+               BZ_UPDATE_CRC ( c_calculatedBlockCRC, c_state_out_ch );
+               c_state_out_len--;
+               cs_next_out++;
+               cs_avail_out--;
+            }
+            s_state_out_len_eq_one:
+            {
+               if (cs_avail_out == 0) { 
+                  c_state_out_len = 1; goto return_notr;
+               };
+               *( (UChar*)(cs_next_out) ) = c_state_out_ch;
+               BZ_UPDATE_CRC ( c_calculatedBlockCRC, c_state_out_ch );
+               cs_next_out++;
+               cs_avail_out--;
+            }
+         }   
+         /* Only caused by corrupt data stream? */
+         if (c_nblock_used > s_save_nblockPP)
+            return True;
+
+         /* can a new run be started? */
+         if (c_nblock_used == s_save_nblockPP) {
+            c_state_out_len = 0; goto return_notr;
+         };   
+         c_state_out_ch = c_k0;
+         BZ_GET_FAST_C(k1); c_nblock_used++;
+         if (k1 != c_k0) { 
+            c_k0 = k1; goto s_state_out_len_eq_one; 
+         };
+         if (c_nblock_used == s_save_nblockPP) 
+            goto s_state_out_len_eq_one;
+   
+         c_state_out_len = 2;
+         BZ_GET_FAST_C(k1); c_nblock_used++;
+         if (c_nblock_used == s_save_nblockPP) continue;
+         if (k1 != c_k0) { c_k0 = k1; continue; };
+   
+         c_state_out_len = 3;
+         BZ_GET_FAST_C(k1); c_nblock_used++;
+         if (c_nblock_used == s_save_nblockPP) continue;
+         if (k1 != c_k0) { c_k0 = k1; continue; };
+   
+         BZ_GET_FAST_C(k1); c_nblock_used++;
+         c_state_out_len = ((Int32)k1) + 4;
+         BZ_GET_FAST_C(c_k0); c_nblock_used++;
+      }
+
+      return_notr:
+      total_out_lo32_old = s->strm->total_out_lo32;
+      s->strm->total_out_lo32 += (avail_out_INIT - cs_avail_out);
+      if (s->strm->total_out_lo32 < total_out_lo32_old)
+         s->strm->total_out_hi32++;
+
+      /* save */
+      s->calculatedBlockCRC = c_calculatedBlockCRC;
+      s->state_out_ch       = c_state_out_ch;
+      s->state_out_len      = c_state_out_len;
+      s->nblock_used        = c_nblock_used;
+      s->k0                 = c_k0;
+      s->tt                 = c_tt;
+      s->tPos               = c_tPos;
+      s->strm->next_out     = cs_next_out;
+      s->strm->avail_out    = cs_avail_out;
+      /* end save */
+   }
+   return False;
+}
+
+
+
+/*---------------------------------------------------*/
+__inline__ Int32 BZ2_indexIntoF ( Int32 indx, Int32 *cftab )
+{
+   Int32 nb, na, mid;
+   nb = 0;
+   na = 256;
+   do {
+      mid = (nb + na) >> 1;
+      if (indx >= cftab[mid]) nb = mid; else na = mid;
+   }
+   while (na - nb != 1);
+   return nb;
+}
+
+
+/*---------------------------------------------------*/
+/* Return  True iff data corruption is discovered.
+   Returns False if there is no problem.
+*/
+static
+Bool unRLE_obuf_to_output_SMALL ( DState* s )
+{
+   UChar k1;
+
+   if (s->blockRandomised) {
+
+      while (True) {
+         /* try to finish existing run */
+         while (True) {
+            if (s->strm->avail_out == 0) return False;
+            if (s->state_out_len == 0) break;
+            *( (UChar*)(s->strm->next_out) ) = s->state_out_ch;
+            BZ_UPDATE_CRC ( s->calculatedBlockCRC, s->state_out_ch );
+            s->state_out_len--;
+            s->strm->next_out++;
+            s->strm->avail_out--;
+            s->strm->total_out_lo32++;
+            if (s->strm->total_out_lo32 == 0) s->strm->total_out_hi32++;
+         }
+   
+         /* can a new run be started? */
+         if (s->nblock_used == s->save_nblock+1) return False;
+
+         /* Only caused by corrupt data stream? */
+         if (s->nblock_used > s->save_nblock+1)
+            return True;
+   
+         s->state_out_len = 1;
+         s->state_out_ch = s->k0;
+         BZ_GET_SMALL(k1); BZ_RAND_UPD_MASK; 
+         k1 ^= BZ_RAND_MASK; s->nblock_used++;
+         if (s->nblock_used == s->save_nblock+1) continue;
+         if (k1 != s->k0) { s->k0 = k1; continue; };
+   
+         s->state_out_len = 2;
+         BZ_GET_SMALL(k1); BZ_RAND_UPD_MASK; 
+         k1 ^= BZ_RAND_MASK; s->nblock_used++;
+         if (s->nblock_used == s->save_nblock+1) continue;
+         if (k1 != s->k0) { s->k0 = k1; continue; };
+   
+         s->state_out_len = 3;
+         BZ_GET_SMALL(k1); BZ_RAND_UPD_MASK; 
+         k1 ^= BZ_RAND_MASK; s->nblock_used++;
+         if (s->nblock_used == s->save_nblock+1) continue;
+         if (k1 != s->k0) { s->k0 = k1; continue; };
+   
+         BZ_GET_SMALL(k1); BZ_RAND_UPD_MASK; 
+         k1 ^= BZ_RAND_MASK; s->nblock_used++;
+         s->state_out_len = ((Int32)k1) + 4;
+         BZ_GET_SMALL(s->k0); BZ_RAND_UPD_MASK; 
+         s->k0 ^= BZ_RAND_MASK; s->nblock_used++;
+      }
+
+   } else {
+
+      while (True) {
+         /* try to finish existing run */
+         while (True) {
+            if (s->strm->avail_out == 0) return False;
+            if (s->state_out_len == 0) break;
+            *( (UChar*)(s->strm->next_out) ) = s->state_out_ch;
+            BZ_UPDATE_CRC ( s->calculatedBlockCRC, s->state_out_ch );
+            s->state_out_len--;
+            s->strm->next_out++;
+            s->strm->avail_out--;
+            s->strm->total_out_lo32++;
+            if (s->strm->total_out_lo32 == 0) s->strm->total_out_hi32++;
+         }
+   
+         /* can a new run be started? */
+         if (s->nblock_used == s->save_nblock+1) return False;
+
+         /* Only caused by corrupt data stream? */
+         if (s->nblock_used > s->save_nblock+1)
+            return True;
+   
+         s->state_out_len = 1;
+         s->state_out_ch = s->k0;
+         BZ_GET_SMALL(k1); s->nblock_used++;
+         if (s->nblock_used == s->save_nblock+1) continue;
+         if (k1 != s->k0) { s->k0 = k1; continue; };
+   
+         s->state_out_len = 2;
+         BZ_GET_SMALL(k1); s->nblock_used++;
+         if (s->nblock_used == s->save_nblock+1) continue;
+         if (k1 != s->k0) { s->k0 = k1; continue; };
+   
+         s->state_out_len = 3;
+         BZ_GET_SMALL(k1); s->nblock_used++;
+         if (s->nblock_used == s->save_nblock+1) continue;
+         if (k1 != s->k0) { s->k0 = k1; continue; };
+   
+         BZ_GET_SMALL(k1); s->nblock_used++;
+         s->state_out_len = ((Int32)k1) + 4;
+         BZ_GET_SMALL(s->k0); s->nblock_used++;
+      }
+
+   }
+}
+
+
+/*---------------------------------------------------*/
+int BZ_API(BZ2_bzDecompress) ( bz_stream *strm )
+{
+   Bool    corrupt;
+   DState* s;
+   if (strm == NULL) return BZ_PARAM_ERROR;
+   s = strm->state;
+   if (s == NULL) return BZ_PARAM_ERROR;
+   if (s->strm != strm) return BZ_PARAM_ERROR;
+
+   while (True) {
+      if (s->state == BZ_X_IDLE) return BZ_SEQUENCE_ERROR;
+      if (s->state == BZ_X_OUTPUT) {
+         if (s->smallDecompress)
+            corrupt = unRLE_obuf_to_output_SMALL ( s ); else
+            corrupt = unRLE_obuf_to_output_FAST  ( s );
+         if (corrupt) return BZ_DATA_ERROR;
+         if (s->nblock_used == s->save_nblock+1 && s->state_out_len == 0) {
+            BZ_FINALISE_CRC ( s->calculatedBlockCRC );
+            if (s->verbosity >= 3) 
+               VPrintf2 ( " {0x%08x, 0x%08x}", s->storedBlockCRC, 
+                          s->calculatedBlockCRC );
+            if (s->verbosity >= 2) VPrintf0 ( "]" );
+            if (s->calculatedBlockCRC != s->storedBlockCRC)
+               return BZ_DATA_ERROR;
+            s->calculatedCombinedCRC 
+               = (s->calculatedCombinedCRC << 1) | 
+                    (s->calculatedCombinedCRC >> 31);
+            s->calculatedCombinedCRC ^= s->calculatedBlockCRC;
+            s->state = BZ_X_BLKHDR_1;
+         } else {
+            return BZ_OK;
+         }
+      }
+      if (s->state >= BZ_X_MAGIC_1) {
+         Int32 r = BZ2_decompress ( s );
+         if (r == BZ_STREAM_END) {
+            if (s->verbosity >= 3)
+               VPrintf2 ( "\n    combined CRCs: stored = 0x%08x, computed = 0x%08x", 
+                          s->storedCombinedCRC, s->calculatedCombinedCRC );
+            if (s->calculatedCombinedCRC != s->storedCombinedCRC)
+               return BZ_DATA_ERROR;
+            return r;
+         }
+         if (s->state != BZ_X_OUTPUT) return r;
+      }
+   }
+
+   AssertH ( 0, 6001 );
+
+   return 0;  /*NOTREACHED*/
+}
+
+
+/*---------------------------------------------------*/
+int BZ_API(BZ2_bzDecompressEnd)  ( bz_stream *strm )
+{
+   DState* s;
+   if (strm == NULL) return BZ_PARAM_ERROR;
+   s = strm->state;
+   if (s == NULL) return BZ_PARAM_ERROR;
+   if (s->strm != strm) return BZ_PARAM_ERROR;
+
+   if (s->tt   != NULL) BZFREE(s->tt);
+   if (s->ll16 != NULL) BZFREE(s->ll16);
+   if (s->ll4  != NULL) BZFREE(s->ll4);
+
+   BZFREE(strm->state);
+   strm->state = NULL;
+
+   return BZ_OK;
+}
+
+
+#ifndef BZ_NO_STDIO
+/*---------------------------------------------------*/
+/*--- File I/O stuff                              ---*/
+/*---------------------------------------------------*/
+
+#define BZ_SETERR(eee)                    \
+{                                         \
+   if (bzerror != NULL) *bzerror = eee;   \
+   if (bzf != NULL) bzf->lastErr = eee;   \
+}
+
+typedef 
+   struct {
+      FILE*     handle;
+      Char      buf[BZ_MAX_UNUSED];
+      Int32     bufN;
+      Bool      writing;
+      bz_stream strm;
+      Int32     lastErr;
+      Bool      initialisedOk;
+   }
+   bzFile;
+
+
+/*---------------------------------------------*/
+static Bool myfeof ( FILE* f )
+{
+   Int32 c = fgetc ( f );
+   if (c == EOF) return True;
+   ungetc ( c, f );
+   return False;
+}
+
+
+/*---------------------------------------------------*/
+BZFILE* BZ_API(BZ2_bzWriteOpen) 
+                    ( int*  bzerror,      
+                      FILE* f, 
+                      int   blockSize100k, 
+                      int   verbosity,
+                      int   workFactor )
+{
+   Int32   ret;
+   bzFile* bzf = NULL;
+
+   BZ_SETERR(BZ_OK);
+
+   if (f == NULL ||
+       (blockSize100k < 1 || blockSize100k > 9) ||
+       (workFactor < 0 || workFactor > 250) ||
+       (verbosity < 0 || verbosity > 4))
+      { BZ_SETERR(BZ_PARAM_ERROR); return NULL; };
+
+   if (ferror(f))
+      { BZ_SETERR(BZ_IO_ERROR); return NULL; };
+
+   bzf = malloc ( sizeof(bzFile) );
+   if (bzf == NULL)
+      { BZ_SETERR(BZ_MEM_ERROR); return NULL; };
+
+   BZ_SETERR(BZ_OK);
+   bzf->initialisedOk = False;
+   bzf->bufN          = 0;
+   bzf->handle        = f;
+   bzf->writing       = True;
+   bzf->strm.bzalloc  = NULL;
+   bzf->strm.bzfree   = NULL;
+   bzf->strm.opaque   = NULL;
+
+   if (workFactor == 0) workFactor = 30;
+   ret = BZ2_bzCompressInit ( &(bzf->strm), blockSize100k, 
+                              verbosity, workFactor );
+   if (ret != BZ_OK)
+      { BZ_SETERR(ret); free(bzf); return NULL; };
+
+   bzf->strm.avail_in = 0;
+   bzf->initialisedOk = True;
+   return bzf;   
+}
+
+
+
+/*---------------------------------------------------*/
+void BZ_API(BZ2_bzWrite)
+             ( int*    bzerror, 
+               BZFILE* b, 
+               void*   buf, 
+               int     len )
+{
+   Int32 n, n2, ret;
+   bzFile* bzf = (bzFile*)b;
+
+   BZ_SETERR(BZ_OK);
+   if (bzf == NULL || buf == NULL || len < 0)
+      { BZ_SETERR(BZ_PARAM_ERROR); return; };
+   if (!(bzf->writing))
+      { BZ_SETERR(BZ_SEQUENCE_ERROR); return; };
+   if (ferror(bzf->handle))
+      { BZ_SETERR(BZ_IO_ERROR); return; };
+
+   if (len == 0)
+      { BZ_SETERR(BZ_OK); return; };
+
+   bzf->strm.avail_in = len;
+   bzf->strm.next_in  = buf;
+
+   while (True) {
+      bzf->strm.avail_out = BZ_MAX_UNUSED;
+      bzf->strm.next_out = bzf->buf;
+      ret = BZ2_bzCompress ( &(bzf->strm), BZ_RUN );
+      if (ret != BZ_RUN_OK)
+         { BZ_SETERR(ret); return; };
+
+      if (bzf->strm.avail_out < BZ_MAX_UNUSED) {
+         n = BZ_MAX_UNUSED - bzf->strm.avail_out;
+         n2 = fwrite ( (void*)(bzf->buf), sizeof(UChar), 
+                       n, bzf->handle );
+         if (n != n2 || ferror(bzf->handle))
+            { BZ_SETERR(BZ_IO_ERROR); return; };
+      }
+
+      if (bzf->strm.avail_in == 0)
+         { BZ_SETERR(BZ_OK); return; };
+   }
+}
+
+
+/*---------------------------------------------------*/
+void BZ_API(BZ2_bzWriteClose)
+                  ( int*          bzerror, 
+                    BZFILE*       b, 
+                    int           abandon,
+                    unsigned int* nbytes_in,
+                    unsigned int* nbytes_out )
+{
+   BZ2_bzWriteClose64 ( bzerror, b, abandon, 
+                        nbytes_in, NULL, nbytes_out, NULL );
+}
+
+
+void BZ_API(BZ2_bzWriteClose64)
+                  ( int*          bzerror, 
+                    BZFILE*       b, 
+                    int           abandon,
+                    unsigned int* nbytes_in_lo32,
+                    unsigned int* nbytes_in_hi32,
+                    unsigned int* nbytes_out_lo32,
+                    unsigned int* nbytes_out_hi32 )
+{
+   Int32   n, n2, ret;
+   bzFile* bzf = (bzFile*)b;
+
+   if (bzf == NULL)
+      { BZ_SETERR(BZ_OK); return; };
+   if (!(bzf->writing))
+      { BZ_SETERR(BZ_SEQUENCE_ERROR); return; };
+   if (ferror(bzf->handle))
+      { BZ_SETERR(BZ_IO_ERROR); return; };
+
+   if (nbytes_in_lo32 != NULL) *nbytes_in_lo32 = 0;
+   if (nbytes_in_hi32 != NULL) *nbytes_in_hi32 = 0;
+   if (nbytes_out_lo32 != NULL) *nbytes_out_lo32 = 0;
+   if (nbytes_out_hi32 != NULL) *nbytes_out_hi32 = 0;
+
+   if ((!abandon) && bzf->lastErr == BZ_OK) {
+      while (True) {
+         bzf->strm.avail_out = BZ_MAX_UNUSED;
+         bzf->strm.next_out = bzf->buf;
+         ret = BZ2_bzCompress ( &(bzf->strm), BZ_FINISH );
+         if (ret != BZ_FINISH_OK && ret != BZ_STREAM_END)
+            { BZ_SETERR(ret); return; };
+
+         if (bzf->strm.avail_out < BZ_MAX_UNUSED) {
+            n = BZ_MAX_UNUSED - bzf->strm.avail_out;
+            n2 = fwrite ( (void*)(bzf->buf), sizeof(UChar), 
+                          n, bzf->handle );
+            if (n != n2 || ferror(bzf->handle))
+               { BZ_SETERR(BZ_IO_ERROR); return; };
+         }
+
+         if (ret == BZ_STREAM_END) break;
+      }
+   }
+
+   if ( !abandon && !ferror ( bzf->handle ) ) {
+      fflush ( bzf->handle );
+      if (ferror(bzf->handle))
+         { BZ_SETERR(BZ_IO_ERROR); return; };
+   }
+
+   if (nbytes_in_lo32 != NULL)
+      *nbytes_in_lo32 = bzf->strm.total_in_lo32;
+   if (nbytes_in_hi32 != NULL)
+      *nbytes_in_hi32 = bzf->strm.total_in_hi32;
+   if (nbytes_out_lo32 != NULL)
+      *nbytes_out_lo32 = bzf->strm.total_out_lo32;
+   if (nbytes_out_hi32 != NULL)
+      *nbytes_out_hi32 = bzf->strm.total_out_hi32;
+
+   BZ_SETERR(BZ_OK);
+   BZ2_bzCompressEnd ( &(bzf->strm) );
+   free ( bzf );
+}
+
+
+/*---------------------------------------------------*/
+BZFILE* BZ_API(BZ2_bzReadOpen) 
+                   ( int*  bzerror, 
+                     FILE* f, 
+                     int   verbosity,
+                     int   small,
+                     void* unused,
+                     int   nUnused )
+{
+   bzFile* bzf = NULL;
+   int     ret;
+
+   BZ_SETERR(BZ_OK);
+
+   if (f == NULL || 
+       (small != 0 && small != 1) ||
+       (verbosity < 0 || verbosity > 4) ||
+       (unused == NULL && nUnused != 0) ||
+       (unused != NULL && (nUnused < 0 || nUnused > BZ_MAX_UNUSED)))
+      { BZ_SETERR(BZ_PARAM_ERROR); return NULL; };
+
+   if (ferror(f))
+      { BZ_SETERR(BZ_IO_ERROR); return NULL; };
+
+   bzf = malloc ( sizeof(bzFile) );
+   if (bzf == NULL) 
+      { BZ_SETERR(BZ_MEM_ERROR); return NULL; };
+
+   BZ_SETERR(BZ_OK);
+
+   bzf->initialisedOk = False;
+   bzf->handle        = f;
+   bzf->bufN          = 0;
+   bzf->writing       = False;
+   bzf->strm.bzalloc  = NULL;
+   bzf->strm.bzfree   = NULL;
+   bzf->strm.opaque   = NULL;
+   
+   while (nUnused > 0) {
+      bzf->buf[bzf->bufN] = *((UChar*)(unused)); bzf->bufN++;
+      unused = ((void*)( 1 + ((UChar*)(unused))  ));
+      nUnused--;
+   }
+
+   ret = BZ2_bzDecompressInit ( &(bzf->strm), verbosity, small );
+   if (ret != BZ_OK)
+      { BZ_SETERR(ret); free(bzf); return NULL; };
+
+   bzf->strm.avail_in = bzf->bufN;
+   bzf->strm.next_in  = bzf->buf;
+
+   bzf->initialisedOk = True;
+   return bzf;   
+}
+
+
+/*---------------------------------------------------*/
+void BZ_API(BZ2_bzReadClose) ( int *bzerror, BZFILE *b )
+{
+   bzFile* bzf = (bzFile*)b;
+
+   BZ_SETERR(BZ_OK);
+   if (bzf == NULL)
+      { BZ_SETERR(BZ_OK); return; };
+
+   if (bzf->writing)
+      { BZ_SETERR(BZ_SEQUENCE_ERROR); return; };
+
+   if (bzf->initialisedOk)
+      (void)BZ2_bzDecompressEnd ( &(bzf->strm) );
+   free ( bzf );
+}
+
+
+/*---------------------------------------------------*/
+int BZ_API(BZ2_bzRead) 
+           ( int*    bzerror, 
+             BZFILE* b, 
+             void*   buf, 
+             int     len )
+{
+   Int32   n, ret;
+   bzFile* bzf = (bzFile*)b;
+
+   BZ_SETERR(BZ_OK);
+
+   if (bzf == NULL || buf == NULL || len < 0)
+      { BZ_SETERR(BZ_PARAM_ERROR); return 0; };
+
+   if (bzf->writing)
+      { BZ_SETERR(BZ_SEQUENCE_ERROR); return 0; };
+
+   if (len == 0)
+      { BZ_SETERR(BZ_OK); return 0; };
+
+   bzf->strm.avail_out = len;
+   bzf->strm.next_out = buf;
+
+   while (True) {
+
+      if (ferror(bzf->handle)) 
+         { BZ_SETERR(BZ_IO_ERROR); return 0; };
+
+      if (bzf->strm.avail_in == 0 && !myfeof(bzf->handle)) {
+         n = fread ( bzf->buf, sizeof(UChar), 
+                     BZ_MAX_UNUSED, bzf->handle );
+         if (ferror(bzf->handle))
+            { BZ_SETERR(BZ_IO_ERROR); return 0; };
+         bzf->bufN = n;
+         bzf->strm.avail_in = bzf->bufN;
+         bzf->strm.next_in = bzf->buf;
+      }
+
+      ret = BZ2_bzDecompress ( &(bzf->strm) );
+
+      if (ret != BZ_OK && ret != BZ_STREAM_END)
+         { BZ_SETERR(ret); return 0; };
+
+      if (ret == BZ_OK && myfeof(bzf->handle) && 
+          bzf->strm.avail_in == 0 && bzf->strm.avail_out > 0)
+         { BZ_SETERR(BZ_UNEXPECTED_EOF); return 0; };
+
+      if (ret == BZ_STREAM_END)
+         { BZ_SETERR(BZ_STREAM_END);
+           return len - bzf->strm.avail_out; };
+      if (bzf->strm.avail_out == 0)
+         { BZ_SETERR(BZ_OK); return len; };
+      
+   }
+
+   return 0; /*not reached*/
+}
+
+
+/*---------------------------------------------------*/
+void BZ_API(BZ2_bzReadGetUnused) 
+                     ( int*    bzerror, 
+                       BZFILE* b, 
+                       void**  unused, 
+                       int*    nUnused )
+{
+   bzFile* bzf = (bzFile*)b;
+   if (bzf == NULL)
+      { BZ_SETERR(BZ_PARAM_ERROR); return; };
+   if (bzf->lastErr != BZ_STREAM_END)
+      { BZ_SETERR(BZ_SEQUENCE_ERROR); return; };
+   if (unused == NULL || nUnused == NULL)
+      { BZ_SETERR(BZ_PARAM_ERROR); return; };
+
+   BZ_SETERR(BZ_OK);
+   *nUnused = bzf->strm.avail_in;
+   *unused = bzf->strm.next_in;
+}
+#endif
+
+
+/*---------------------------------------------------*/
+/*--- Misc convenience stuff                      ---*/
+/*---------------------------------------------------*/
+
+/*---------------------------------------------------*/
+int BZ_API(BZ2_bzBuffToBuffCompress) 
+                         ( char*         dest, 
+                           unsigned int* destLen,
+                           char*         source, 
+                           unsigned int  sourceLen,
+                           int           blockSize100k, 
+                           int           verbosity, 
+                           int           workFactor )
+{
+   bz_stream strm;
+   int ret;
+
+   if (dest == NULL || destLen == NULL || 
+       source == NULL ||
+       blockSize100k < 1 || blockSize100k > 9 ||
+       verbosity < 0 || verbosity > 4 ||
+       workFactor < 0 || workFactor > 250) 
+      return BZ_PARAM_ERROR;
+
+   if (workFactor == 0) workFactor = 30;
+   strm.bzalloc = NULL;
+   strm.bzfree = NULL;
+   strm.opaque = NULL;
+   ret = BZ2_bzCompressInit ( &strm, blockSize100k, 
+                              verbosity, workFactor );
+   if (ret != BZ_OK) return ret;
+
+   strm.next_in = source;
+   strm.next_out = dest;
+   strm.avail_in = sourceLen;
+   strm.avail_out = *destLen;
+
+   ret = BZ2_bzCompress ( &strm, BZ_FINISH );
+   if (ret == BZ_FINISH_OK) goto output_overflow;
+   if (ret != BZ_STREAM_END) goto errhandler;
+
+   /* normal termination */
+   *destLen -= strm.avail_out;   
+   BZ2_bzCompressEnd ( &strm );
+   return BZ_OK;
+
+   output_overflow:
+   BZ2_bzCompressEnd ( &strm );
+   return BZ_OUTBUFF_FULL;
+
+   errhandler:
+   BZ2_bzCompressEnd ( &strm );
+   return ret;
+}
+
+
+/*---------------------------------------------------*/
+int BZ_API(BZ2_bzBuffToBuffDecompress) 
+                           ( char*         dest, 
+                             unsigned int* destLen,
+                             char*         source, 
+                             unsigned int  sourceLen,
+                             int           small,
+                             int           verbosity )
+{
+   bz_stream strm;
+   int ret;
+
+   if (dest == NULL || destLen == NULL || 
+       source == NULL ||
+       (small != 0 && small != 1) ||
+       verbosity < 0 || verbosity > 4) 
+          return BZ_PARAM_ERROR;
+
+   strm.bzalloc = NULL;
+   strm.bzfree = NULL;
+   strm.opaque = NULL;
+   ret = BZ2_bzDecompressInit ( &strm, verbosity, small );
+   if (ret != BZ_OK) return ret;
+
+   strm.next_in = source;
+   strm.next_out = dest;
+   strm.avail_in = sourceLen;
+   strm.avail_out = *destLen;
+
+   ret = BZ2_bzDecompress ( &strm );
+   if (ret == BZ_OK) goto output_overflow_or_eof;
+   if (ret != BZ_STREAM_END) goto errhandler;
+
+   /* normal termination */
+   *destLen -= strm.avail_out;
+   BZ2_bzDecompressEnd ( &strm );
+   return BZ_OK;
+
+   output_overflow_or_eof:
+   if (strm.avail_out > 0) {
+      BZ2_bzDecompressEnd ( &strm );
+      return BZ_UNEXPECTED_EOF;
+   } else {
+      BZ2_bzDecompressEnd ( &strm );
+      return BZ_OUTBUFF_FULL;
+   };      
+
+   errhandler:
+   BZ2_bzDecompressEnd ( &strm );
+   return ret; 
+}
+
+
+/*---------------------------------------------------*/
+/*--
+   Code contributed by Yoshioka Tsuneo (tsuneo@rr.iij4u.or.jp)
+   to support better zlib compatibility.
+   This code is not _officially_ part of libbzip2 (yet);
+   I haven't tested it, documented it, or considered the
+   threading-safeness of it.
+   If this code breaks, please contact both Yoshioka and me.
+--*/
+/*---------------------------------------------------*/
+
+/*---------------------------------------------------*/
+/*--
+   return version like "0.9.5d, 4-Sept-1999".
+--*/
+const char * BZ_API(BZ2_bzlibVersion)(void)
+{
+   return BZ_VERSION;
+}
+
+
+#ifndef BZ_NO_STDIO
+/*---------------------------------------------------*/
+
+#if defined(_WIN32) || defined(OS2) || defined(MSDOS)
+#   include <fcntl.h>
+#   include <io.h>
+#   define SET_BINARY_MODE(file) setmode(fileno(file),O_BINARY)
+#else
+#   define SET_BINARY_MODE(file)
+#endif
+static
+BZFILE * bzopen_or_bzdopen
+               ( const char *path,   /* no use when bzdopen */
+                 int fd,             /* no use when bzdopen */
+                 const char *mode,
+                 int open_mode)      /* bzopen: 0, bzdopen:1 */
+{
+   int    bzerr;
+   char   unused[BZ_MAX_UNUSED];
+   int    blockSize100k = 9;
+   int    writing       = 0;
+   char   mode2[10]     = "";
+   FILE   *fp           = NULL;
+   BZFILE *bzfp         = NULL;
+   int    verbosity     = 0;
+   int    workFactor    = 30;
+   int    smallMode     = 0;
+   int    nUnused       = 0; 
+
+   if (mode == NULL) return NULL;
+   while (*mode) {
+      switch (*mode) {
+      case 'r':
+         writing = 0; break;
+      case 'w':
+         writing = 1; break;
+      case 's':
+         smallMode = 1; break;
+      default:
+         if (isdigit((int)(*mode))) {
+            blockSize100k = *mode-BZ_HDR_0;
+         }
+      }
+      mode++;
+   }
+   strcat(mode2, writing ? "w" : "r" );
+   strcat(mode2,"b");   /* binary mode */
+
+   if (open_mode==0) {
+      if (path==NULL || strcmp(path,"")==0) {
+        fp = (writing ? stdout : stdin);
+        SET_BINARY_MODE(fp);
+      } else {
+        fp = fopen(path,mode2);
+      }
+   } else {
+#ifdef BZ_STRICT_ANSI
+      fp = NULL;
+#else
+      fp = fdopen(fd,mode2);
+#endif
+   }
+   if (fp == NULL) return NULL;
+
+   if (writing) {
+      /* Guard against total chaos and anarchy -- JRS */
+      if (blockSize100k < 1) blockSize100k = 1;
+      if (blockSize100k > 9) blockSize100k = 9; 
+      bzfp = BZ2_bzWriteOpen(&bzerr,fp,blockSize100k,
+                             verbosity,workFactor);
+   } else {
+      bzfp = BZ2_bzReadOpen(&bzerr,fp,verbosity,smallMode,
+                            unused,nUnused);
+   }
+   if (bzfp == NULL) {
+      if (fp != stdin && fp != stdout) fclose(fp);
+      return NULL;
+   }
+   return bzfp;
+}
+
+
+/*---------------------------------------------------*/
+/*--
+   open file for read or write.
+      ex) bzopen("file","w9")
+      case path="" or NULL => use stdin or stdout.
+--*/
+BZFILE * BZ_API(BZ2_bzopen)
+               ( const char *path,
+                 const char *mode )
+{
+   return bzopen_or_bzdopen(path,-1,mode,/*bzopen*/0);
+}
+
+
+/*---------------------------------------------------*/
+BZFILE * BZ_API(BZ2_bzdopen)
+               ( int fd,
+                 const char *mode )
+{
+   return bzopen_or_bzdopen(NULL,fd,mode,/*bzdopen*/1);
+}
+
+
+/*---------------------------------------------------*/
+int BZ_API(BZ2_bzread) (BZFILE* b, void* buf, int len )
+{
+   int bzerr, nread;
+   if (((bzFile*)b)->lastErr == BZ_STREAM_END) return 0;
+   nread = BZ2_bzRead(&bzerr,b,buf,len);
+   if (bzerr == BZ_OK || bzerr == BZ_STREAM_END) {
+      return nread;
+   } else {
+      return -1;
+   }
+}
+
+
+/*---------------------------------------------------*/
+int BZ_API(BZ2_bzwrite) (BZFILE* b, void* buf, int len )
+{
+   int bzerr;
+
+   BZ2_bzWrite(&bzerr,b,buf,len);
+   if(bzerr == BZ_OK){
+      return len;
+   }else{
+      return -1;
+   }
+}
+
+
+/*---------------------------------------------------*/
+int BZ_API(BZ2_bzflush) (BZFILE *b)
+{
+   /* do nothing now... */
+   return 0;
+}
+
+
+/*---------------------------------------------------*/
+void BZ_API(BZ2_bzclose) (BZFILE* b)
+{
+   int bzerr;
+   FILE *fp;
+   
+   if (b==NULL) {return;}
+   fp = ((bzFile *)b)->handle;
+   if(((bzFile*)b)->writing){
+      BZ2_bzWriteClose(&bzerr,b,0,NULL,NULL);
+      if(bzerr != BZ_OK){
+         BZ2_bzWriteClose(NULL,b,1,NULL,NULL);
+      }
+   }else{
+      BZ2_bzReadClose(&bzerr,b);
+   }
+   if(fp!=stdin && fp!=stdout){
+      fclose(fp);
+   }
+}
+
+
+/*---------------------------------------------------*/
+/*--
+   return last error code 
+--*/
+static const char *bzerrorstrings[] = {
+       "OK"
+      ,"SEQUENCE_ERROR"
+      ,"PARAM_ERROR"
+      ,"MEM_ERROR"
+      ,"DATA_ERROR"
+      ,"DATA_ERROR_MAGIC"
+      ,"IO_ERROR"
+      ,"UNEXPECTED_EOF"
+      ,"OUTBUFF_FULL"
+      ,"CONFIG_ERROR"
+      ,"???"   /* for future */
+      ,"???"   /* for future */
+      ,"???"   /* for future */
+      ,"???"   /* for future */
+      ,"???"   /* for future */
+      ,"???"   /* for future */
+};
+
+
+const char * BZ_API(BZ2_bzerror) (BZFILE *b, int *errnum)
+{
+   int err = ((bzFile *)b)->lastErr;
+
+   if(err>0) err = 0;
+   *errnum = err;
+   return bzerrorstrings[err*-1];
+}
+#endif
+
+
+/*-------------------------------------------------------------*/
+/*--- end                                           bzlib.c ---*/
+/*-------------------------------------------------------------*/
diff --git a/cbits/bzlib.h b/cbits/bzlib.h
new file mode 100644
--- /dev/null
+++ b/cbits/bzlib.h
@@ -0,0 +1,282 @@
+
+/*-------------------------------------------------------------*/
+/*--- Public header file for the library.                   ---*/
+/*---                                               bzlib.h ---*/
+/*-------------------------------------------------------------*/
+
+/* ------------------------------------------------------------------
+   This file is part of bzip2/libbzip2, a program and library for
+   lossless, block-sorting data compression.
+
+   bzip2/libbzip2 version 1.0.8 of 13 July 2019
+   Copyright (C) 1996-2019 Julian Seward <jseward@acm.org>
+
+   Please read the WARNING, DISCLAIMER and PATENTS sections in the 
+   README file.
+
+   This program is released under the terms of the license contained
+   in the file LICENSE.
+   ------------------------------------------------------------------ */
+
+
+#ifndef _BZLIB_H
+#define _BZLIB_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define BZ_RUN               0
+#define BZ_FLUSH             1
+#define BZ_FINISH            2
+
+#define BZ_OK                0
+#define BZ_RUN_OK            1
+#define BZ_FLUSH_OK          2
+#define BZ_FINISH_OK         3
+#define BZ_STREAM_END        4
+#define BZ_SEQUENCE_ERROR    (-1)
+#define BZ_PARAM_ERROR       (-2)
+#define BZ_MEM_ERROR         (-3)
+#define BZ_DATA_ERROR        (-4)
+#define BZ_DATA_ERROR_MAGIC  (-5)
+#define BZ_IO_ERROR          (-6)
+#define BZ_UNEXPECTED_EOF    (-7)
+#define BZ_OUTBUFF_FULL      (-8)
+#define BZ_CONFIG_ERROR      (-9)
+
+typedef 
+   struct {
+      char *next_in;
+      unsigned int avail_in;
+      unsigned int total_in_lo32;
+      unsigned int total_in_hi32;
+
+      char *next_out;
+      unsigned int avail_out;
+      unsigned int total_out_lo32;
+      unsigned int total_out_hi32;
+
+      void *state;
+
+      void *(*bzalloc)(void *,int,int);
+      void (*bzfree)(void *,void *);
+      void *opaque;
+   } 
+   bz_stream;
+
+
+#ifndef BZ_IMPORT
+#define BZ_EXPORT
+#endif
+
+#ifndef BZ_NO_STDIO
+/* Need a definitition for FILE */
+#include <stdio.h>
+#endif
+
+#ifdef _WIN32
+#   include <windows.h>
+#   ifdef small
+      /* windows.h define small to char */
+#      undef small
+#   endif
+#   ifdef BZ_EXPORT
+#   define BZ_API(func) WINAPI func
+#   define BZ_EXTERN extern
+#   else
+   /* import windows dll dynamically */
+#   define BZ_API(func) (WINAPI * func)
+#   define BZ_EXTERN
+#   endif
+#else
+#   define BZ_API(func) func
+#   define BZ_EXTERN extern
+#endif
+
+
+/*-- Core (low-level) library functions --*/
+
+BZ_EXTERN int BZ_API(BZ2_bzCompressInit) ( 
+      bz_stream* strm, 
+      int        blockSize100k, 
+      int        verbosity, 
+      int        workFactor 
+   );
+
+BZ_EXTERN int BZ_API(BZ2_bzCompress) ( 
+      bz_stream* strm, 
+      int action 
+   );
+
+BZ_EXTERN int BZ_API(BZ2_bzCompressEnd) ( 
+      bz_stream* strm 
+   );
+
+BZ_EXTERN int BZ_API(BZ2_bzDecompressInit) ( 
+      bz_stream *strm, 
+      int       verbosity, 
+      int       small
+   );
+
+BZ_EXTERN int BZ_API(BZ2_bzDecompress) ( 
+      bz_stream* strm 
+   );
+
+BZ_EXTERN int BZ_API(BZ2_bzDecompressEnd) ( 
+      bz_stream *strm 
+   );
+
+
+
+/*-- High(er) level library functions --*/
+
+#ifndef BZ_NO_STDIO
+#define BZ_MAX_UNUSED 5000
+
+typedef void BZFILE;
+
+BZ_EXTERN BZFILE* BZ_API(BZ2_bzReadOpen) ( 
+      int*  bzerror,   
+      FILE* f, 
+      int   verbosity, 
+      int   small,
+      void* unused,    
+      int   nUnused 
+   );
+
+BZ_EXTERN void BZ_API(BZ2_bzReadClose) ( 
+      int*    bzerror, 
+      BZFILE* b 
+   );
+
+BZ_EXTERN void BZ_API(BZ2_bzReadGetUnused) ( 
+      int*    bzerror, 
+      BZFILE* b, 
+      void**  unused,  
+      int*    nUnused 
+   );
+
+BZ_EXTERN int BZ_API(BZ2_bzRead) ( 
+      int*    bzerror, 
+      BZFILE* b, 
+      void*   buf, 
+      int     len 
+   );
+
+BZ_EXTERN BZFILE* BZ_API(BZ2_bzWriteOpen) ( 
+      int*  bzerror,      
+      FILE* f, 
+      int   blockSize100k, 
+      int   verbosity, 
+      int   workFactor 
+   );
+
+BZ_EXTERN void BZ_API(BZ2_bzWrite) ( 
+      int*    bzerror, 
+      BZFILE* b, 
+      void*   buf, 
+      int     len 
+   );
+
+BZ_EXTERN void BZ_API(BZ2_bzWriteClose) ( 
+      int*          bzerror, 
+      BZFILE*       b, 
+      int           abandon, 
+      unsigned int* nbytes_in, 
+      unsigned int* nbytes_out 
+   );
+
+BZ_EXTERN void BZ_API(BZ2_bzWriteClose64) ( 
+      int*          bzerror, 
+      BZFILE*       b, 
+      int           abandon, 
+      unsigned int* nbytes_in_lo32, 
+      unsigned int* nbytes_in_hi32, 
+      unsigned int* nbytes_out_lo32, 
+      unsigned int* nbytes_out_hi32
+   );
+#endif
+
+
+/*-- Utility functions --*/
+
+BZ_EXTERN int BZ_API(BZ2_bzBuffToBuffCompress) ( 
+      char*         dest, 
+      unsigned int* destLen,
+      char*         source, 
+      unsigned int  sourceLen,
+      int           blockSize100k, 
+      int           verbosity, 
+      int           workFactor 
+   );
+
+BZ_EXTERN int BZ_API(BZ2_bzBuffToBuffDecompress) ( 
+      char*         dest, 
+      unsigned int* destLen,
+      char*         source, 
+      unsigned int  sourceLen,
+      int           small, 
+      int           verbosity 
+   );
+
+
+/*--
+   Code contributed by Yoshioka Tsuneo (tsuneo@rr.iij4u.or.jp)
+   to support better zlib compatibility.
+   This code is not _officially_ part of libbzip2 (yet);
+   I haven't tested it, documented it, or considered the
+   threading-safeness of it.
+   If this code breaks, please contact both Yoshioka and me.
+--*/
+
+BZ_EXTERN const char * BZ_API(BZ2_bzlibVersion) (
+      void
+   );
+
+#ifndef BZ_NO_STDIO
+BZ_EXTERN BZFILE * BZ_API(BZ2_bzopen) (
+      const char *path,
+      const char *mode
+   );
+
+BZ_EXTERN BZFILE * BZ_API(BZ2_bzdopen) (
+      int        fd,
+      const char *mode
+   );
+         
+BZ_EXTERN int BZ_API(BZ2_bzread) (
+      BZFILE* b, 
+      void* buf, 
+      int len 
+   );
+
+BZ_EXTERN int BZ_API(BZ2_bzwrite) (
+      BZFILE* b, 
+      void*   buf, 
+      int     len 
+   );
+
+BZ_EXTERN int BZ_API(BZ2_bzflush) (
+      BZFILE* b
+   );
+
+BZ_EXTERN void BZ_API(BZ2_bzclose) (
+      BZFILE* b
+   );
+
+BZ_EXTERN const char * BZ_API(BZ2_bzerror) (
+      BZFILE *b, 
+      int    *errnum
+   );
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
+
+/*-------------------------------------------------------------*/
+/*--- end                                           bzlib.h ---*/
+/*-------------------------------------------------------------*/
diff --git a/cbits/compress.c b/cbits/compress.c
new file mode 100644
--- /dev/null
+++ b/cbits/compress.c
@@ -0,0 +1,672 @@
+
+/*-------------------------------------------------------------*/
+/*--- Compression machinery (not incl block sorting)        ---*/
+/*---                                            compress.c ---*/
+/*-------------------------------------------------------------*/
+
+/* ------------------------------------------------------------------
+   This file is part of bzip2/libbzip2, a program and library for
+   lossless, block-sorting data compression.
+
+   bzip2/libbzip2 version 1.0.8 of 13 July 2019
+   Copyright (C) 1996-2019 Julian Seward <jseward@acm.org>
+
+   Please read the WARNING, DISCLAIMER and PATENTS sections in the 
+   README file.
+
+   This program is released under the terms of the license contained
+   in the file LICENSE.
+   ------------------------------------------------------------------ */
+
+
+/* CHANGES
+    0.9.0    -- original version.
+    0.9.0a/b -- no changes in this file.
+    0.9.0c   -- changed setting of nGroups in sendMTFValues() 
+                so as to do a bit better on small files
+*/
+
+#include "bzlib_private.h"
+
+
+/*---------------------------------------------------*/
+/*--- Bit stream I/O                              ---*/
+/*---------------------------------------------------*/
+
+/*---------------------------------------------------*/
+void BZ2_bsInitWrite ( EState* s )
+{
+   s->bsLive = 0;
+   s->bsBuff = 0;
+}
+
+
+/*---------------------------------------------------*/
+static
+void bsFinishWrite ( EState* s )
+{
+   while (s->bsLive > 0) {
+      s->zbits[s->numZ] = (UChar)(s->bsBuff >> 24);
+      s->numZ++;
+      s->bsBuff <<= 8;
+      s->bsLive -= 8;
+   }
+}
+
+
+/*---------------------------------------------------*/
+#define bsNEEDW(nz)                           \
+{                                             \
+   while (s->bsLive >= 8) {                   \
+      s->zbits[s->numZ]                       \
+         = (UChar)(s->bsBuff >> 24);          \
+      s->numZ++;                              \
+      s->bsBuff <<= 8;                        \
+      s->bsLive -= 8;                         \
+   }                                          \
+}
+
+
+/*---------------------------------------------------*/
+static
+__inline__
+void bsW ( EState* s, Int32 n, UInt32 v )
+{
+   bsNEEDW ( n );
+   s->bsBuff |= (v << (32 - s->bsLive - n));
+   s->bsLive += n;
+}
+
+
+/*---------------------------------------------------*/
+static
+void bsPutUInt32 ( EState* s, UInt32 u )
+{
+   bsW ( s, 8, (u >> 24) & 0xffL );
+   bsW ( s, 8, (u >> 16) & 0xffL );
+   bsW ( s, 8, (u >>  8) & 0xffL );
+   bsW ( s, 8,  u        & 0xffL );
+}
+
+
+/*---------------------------------------------------*/
+static
+void bsPutUChar ( EState* s, UChar c )
+{
+   bsW( s, 8, (UInt32)c );
+}
+
+
+/*---------------------------------------------------*/
+/*--- The back end proper                         ---*/
+/*---------------------------------------------------*/
+
+/*---------------------------------------------------*/
+static
+void makeMaps_e ( EState* s )
+{
+   Int32 i;
+   s->nInUse = 0;
+   for (i = 0; i < 256; i++)
+      if (s->inUse[i]) {
+         s->unseqToSeq[i] = s->nInUse;
+         s->nInUse++;
+      }
+}
+
+
+/*---------------------------------------------------*/
+static
+void generateMTFValues ( EState* s )
+{
+   UChar   yy[256];
+   Int32   i, j;
+   Int32   zPend;
+   Int32   wr;
+   Int32   EOB;
+
+   /* 
+      After sorting (eg, here),
+         s->arr1 [ 0 .. s->nblock-1 ] holds sorted order,
+         and
+         ((UChar*)s->arr2) [ 0 .. s->nblock-1 ] 
+         holds the original block data.
+
+      The first thing to do is generate the MTF values,
+      and put them in
+         ((UInt16*)s->arr1) [ 0 .. s->nblock-1 ].
+      Because there are strictly fewer or equal MTF values
+      than block values, ptr values in this area are overwritten
+      with MTF values only when they are no longer needed.
+
+      The final compressed bitstream is generated into the
+      area starting at
+         (UChar*) (&((UChar*)s->arr2)[s->nblock])
+
+      These storage aliases are set up in bzCompressInit(),
+      except for the last one, which is arranged in 
+      compressBlock().
+   */
+   UInt32* ptr   = s->ptr;
+   UChar* block  = s->block;
+   UInt16* mtfv  = s->mtfv;
+
+   makeMaps_e ( s );
+   EOB = s->nInUse+1;
+
+   for (i = 0; i <= EOB; i++) s->mtfFreq[i] = 0;
+
+   wr = 0;
+   zPend = 0;
+   for (i = 0; i < s->nInUse; i++) yy[i] = (UChar) i;
+
+   for (i = 0; i < s->nblock; i++) {
+      UChar ll_i;
+      AssertD ( wr <= i, "generateMTFValues(1)" );
+      j = ptr[i]-1; if (j < 0) j += s->nblock;
+      ll_i = s->unseqToSeq[block[j]];
+      AssertD ( ll_i < s->nInUse, "generateMTFValues(2a)" );
+
+      if (yy[0] == ll_i) { 
+         zPend++;
+      } else {
+
+         if (zPend > 0) {
+            zPend--;
+            while (True) {
+               if (zPend & 1) {
+                  mtfv[wr] = BZ_RUNB; wr++; 
+                  s->mtfFreq[BZ_RUNB]++; 
+               } else {
+                  mtfv[wr] = BZ_RUNA; wr++; 
+                  s->mtfFreq[BZ_RUNA]++; 
+               }
+               if (zPend < 2) break;
+               zPend = (zPend - 2) / 2;
+            };
+            zPend = 0;
+         }
+         {
+            register UChar  rtmp;
+            register UChar* ryy_j;
+            register UChar  rll_i;
+            rtmp  = yy[1];
+            yy[1] = yy[0];
+            ryy_j = &(yy[1]);
+            rll_i = ll_i;
+            while ( rll_i != rtmp ) {
+               register UChar rtmp2;
+               ryy_j++;
+               rtmp2  = rtmp;
+               rtmp   = *ryy_j;
+               *ryy_j = rtmp2;
+            };
+            yy[0] = rtmp;
+            j = ryy_j - &(yy[0]);
+            mtfv[wr] = j+1; wr++; s->mtfFreq[j+1]++;
+         }
+
+      }
+   }
+
+   if (zPend > 0) {
+      zPend--;
+      while (True) {
+         if (zPend & 1) {
+            mtfv[wr] = BZ_RUNB; wr++; 
+            s->mtfFreq[BZ_RUNB]++; 
+         } else {
+            mtfv[wr] = BZ_RUNA; wr++; 
+            s->mtfFreq[BZ_RUNA]++; 
+         }
+         if (zPend < 2) break;
+         zPend = (zPend - 2) / 2;
+      };
+      zPend = 0;
+   }
+
+   mtfv[wr] = EOB; wr++; s->mtfFreq[EOB]++;
+
+   s->nMTF = wr;
+}
+
+
+/*---------------------------------------------------*/
+#define BZ_LESSER_ICOST  0
+#define BZ_GREATER_ICOST 15
+
+static
+void sendMTFValues ( EState* s )
+{
+   Int32 v, t, i, j, gs, ge, totc, bt, bc, iter;
+   Int32 nSelectors, alphaSize, minLen, maxLen, selCtr;
+   Int32 nGroups, nBytes;
+
+   /*--
+   UChar  len [BZ_N_GROUPS][BZ_MAX_ALPHA_SIZE];
+   is a global since the decoder also needs it.
+
+   Int32  code[BZ_N_GROUPS][BZ_MAX_ALPHA_SIZE];
+   Int32  rfreq[BZ_N_GROUPS][BZ_MAX_ALPHA_SIZE];
+   are also globals only used in this proc.
+   Made global to keep stack frame size small.
+   --*/
+
+
+   UInt16 cost[BZ_N_GROUPS];
+   Int32  fave[BZ_N_GROUPS];
+
+   UInt16* mtfv = s->mtfv;
+
+   if (s->verbosity >= 3)
+      VPrintf3( "      %d in block, %d after MTF & 1-2 coding, "
+                "%d+2 syms in use\n", 
+                s->nblock, s->nMTF, s->nInUse );
+
+   alphaSize = s->nInUse+2;
+   for (t = 0; t < BZ_N_GROUPS; t++)
+      for (v = 0; v < alphaSize; v++)
+         s->len[t][v] = BZ_GREATER_ICOST;
+
+   /*--- Decide how many coding tables to use ---*/
+   AssertH ( s->nMTF > 0, 3001 );
+   if (s->nMTF < 200)  nGroups = 2; else
+   if (s->nMTF < 600)  nGroups = 3; else
+   if (s->nMTF < 1200) nGroups = 4; else
+   if (s->nMTF < 2400) nGroups = 5; else
+                       nGroups = 6;
+
+   /*--- Generate an initial set of coding tables ---*/
+   { 
+      Int32 nPart, remF, tFreq, aFreq;
+
+      nPart = nGroups;
+      remF  = s->nMTF;
+      gs = 0;
+      while (nPart > 0) {
+         tFreq = remF / nPart;
+         ge = gs-1;
+         aFreq = 0;
+         while (aFreq < tFreq && ge < alphaSize-1) {
+            ge++;
+            aFreq += s->mtfFreq[ge];
+         }
+
+         if (ge > gs 
+             && nPart != nGroups && nPart != 1 
+             && ((nGroups-nPart) % 2 == 1)) {
+            aFreq -= s->mtfFreq[ge];
+            ge--;
+         }
+
+         if (s->verbosity >= 3)
+            VPrintf5( "      initial group %d, [%d .. %d], "
+                      "has %d syms (%4.1f%%)\n",
+                      nPart, gs, ge, aFreq, 
+                      (100.0 * (float)aFreq) / (float)(s->nMTF) );
+ 
+         for (v = 0; v < alphaSize; v++)
+            if (v >= gs && v <= ge) 
+               s->len[nPart-1][v] = BZ_LESSER_ICOST; else
+               s->len[nPart-1][v] = BZ_GREATER_ICOST;
+ 
+         nPart--;
+         gs = ge+1;
+         remF -= aFreq;
+      }
+   }
+
+   /*--- 
+      Iterate up to BZ_N_ITERS times to improve the tables.
+   ---*/
+   for (iter = 0; iter < BZ_N_ITERS; iter++) {
+
+      for (t = 0; t < nGroups; t++) fave[t] = 0;
+
+      for (t = 0; t < nGroups; t++)
+         for (v = 0; v < alphaSize; v++)
+            s->rfreq[t][v] = 0;
+
+      /*---
+        Set up an auxiliary length table which is used to fast-track
+	the common case (nGroups == 6). 
+      ---*/
+      if (nGroups == 6) {
+         for (v = 0; v < alphaSize; v++) {
+            s->len_pack[v][0] = (s->len[1][v] << 16) | s->len[0][v];
+            s->len_pack[v][1] = (s->len[3][v] << 16) | s->len[2][v];
+            s->len_pack[v][2] = (s->len[5][v] << 16) | s->len[4][v];
+	 }
+      }
+
+      nSelectors = 0;
+      totc = 0;
+      gs = 0;
+      while (True) {
+
+         /*--- Set group start & end marks. --*/
+         if (gs >= s->nMTF) break;
+         ge = gs + BZ_G_SIZE - 1; 
+         if (ge >= s->nMTF) ge = s->nMTF-1;
+
+         /*-- 
+            Calculate the cost of this group as coded
+            by each of the coding tables.
+         --*/
+         for (t = 0; t < nGroups; t++) cost[t] = 0;
+
+         if (nGroups == 6 && 50 == ge-gs+1) {
+            /*--- fast track the common case ---*/
+            register UInt32 cost01, cost23, cost45;
+            register UInt16 icv;
+            cost01 = cost23 = cost45 = 0;
+
+#           define BZ_ITER(nn)                \
+               icv = mtfv[gs+(nn)];           \
+               cost01 += s->len_pack[icv][0]; \
+               cost23 += s->len_pack[icv][1]; \
+               cost45 += s->len_pack[icv][2]; \
+
+            BZ_ITER(0);  BZ_ITER(1);  BZ_ITER(2);  BZ_ITER(3);  BZ_ITER(4);
+            BZ_ITER(5);  BZ_ITER(6);  BZ_ITER(7);  BZ_ITER(8);  BZ_ITER(9);
+            BZ_ITER(10); BZ_ITER(11); BZ_ITER(12); BZ_ITER(13); BZ_ITER(14);
+            BZ_ITER(15); BZ_ITER(16); BZ_ITER(17); BZ_ITER(18); BZ_ITER(19);
+            BZ_ITER(20); BZ_ITER(21); BZ_ITER(22); BZ_ITER(23); BZ_ITER(24);
+            BZ_ITER(25); BZ_ITER(26); BZ_ITER(27); BZ_ITER(28); BZ_ITER(29);
+            BZ_ITER(30); BZ_ITER(31); BZ_ITER(32); BZ_ITER(33); BZ_ITER(34);
+            BZ_ITER(35); BZ_ITER(36); BZ_ITER(37); BZ_ITER(38); BZ_ITER(39);
+            BZ_ITER(40); BZ_ITER(41); BZ_ITER(42); BZ_ITER(43); BZ_ITER(44);
+            BZ_ITER(45); BZ_ITER(46); BZ_ITER(47); BZ_ITER(48); BZ_ITER(49);
+
+#           undef BZ_ITER
+
+            cost[0] = cost01 & 0xffff; cost[1] = cost01 >> 16;
+            cost[2] = cost23 & 0xffff; cost[3] = cost23 >> 16;
+            cost[4] = cost45 & 0xffff; cost[5] = cost45 >> 16;
+
+         } else {
+	    /*--- slow version which correctly handles all situations ---*/
+            for (i = gs; i <= ge; i++) { 
+               UInt16 icv = mtfv[i];
+               for (t = 0; t < nGroups; t++) cost[t] += s->len[t][icv];
+            }
+         }
+ 
+         /*-- 
+            Find the coding table which is best for this group,
+            and record its identity in the selector table.
+         --*/
+         bc = 999999999; bt = -1;
+         for (t = 0; t < nGroups; t++)
+            if (cost[t] < bc) { bc = cost[t]; bt = t; };
+         totc += bc;
+         fave[bt]++;
+         s->selector[nSelectors] = bt;
+         nSelectors++;
+
+         /*-- 
+            Increment the symbol frequencies for the selected table.
+          --*/
+         if (nGroups == 6 && 50 == ge-gs+1) {
+            /*--- fast track the common case ---*/
+
+#           define BZ_ITUR(nn) s->rfreq[bt][ mtfv[gs+(nn)] ]++
+
+            BZ_ITUR(0);  BZ_ITUR(1);  BZ_ITUR(2);  BZ_ITUR(3);  BZ_ITUR(4);
+            BZ_ITUR(5);  BZ_ITUR(6);  BZ_ITUR(7);  BZ_ITUR(8);  BZ_ITUR(9);
+            BZ_ITUR(10); BZ_ITUR(11); BZ_ITUR(12); BZ_ITUR(13); BZ_ITUR(14);
+            BZ_ITUR(15); BZ_ITUR(16); BZ_ITUR(17); BZ_ITUR(18); BZ_ITUR(19);
+            BZ_ITUR(20); BZ_ITUR(21); BZ_ITUR(22); BZ_ITUR(23); BZ_ITUR(24);
+            BZ_ITUR(25); BZ_ITUR(26); BZ_ITUR(27); BZ_ITUR(28); BZ_ITUR(29);
+            BZ_ITUR(30); BZ_ITUR(31); BZ_ITUR(32); BZ_ITUR(33); BZ_ITUR(34);
+            BZ_ITUR(35); BZ_ITUR(36); BZ_ITUR(37); BZ_ITUR(38); BZ_ITUR(39);
+            BZ_ITUR(40); BZ_ITUR(41); BZ_ITUR(42); BZ_ITUR(43); BZ_ITUR(44);
+            BZ_ITUR(45); BZ_ITUR(46); BZ_ITUR(47); BZ_ITUR(48); BZ_ITUR(49);
+
+#           undef BZ_ITUR
+
+         } else {
+	    /*--- slow version which correctly handles all situations ---*/
+            for (i = gs; i <= ge; i++)
+               s->rfreq[bt][ mtfv[i] ]++;
+         }
+
+         gs = ge+1;
+      }
+      if (s->verbosity >= 3) {
+         VPrintf2 ( "      pass %d: size is %d, grp uses are ", 
+                   iter+1, totc/8 );
+         for (t = 0; t < nGroups; t++)
+            VPrintf1 ( "%d ", fave[t] );
+         VPrintf0 ( "\n" );
+      }
+
+      /*--
+        Recompute the tables based on the accumulated frequencies.
+      --*/
+      /* maxLen was changed from 20 to 17 in bzip2-1.0.3.  See 
+         comment in huffman.c for details. */
+      for (t = 0; t < nGroups; t++)
+         BZ2_hbMakeCodeLengths ( &(s->len[t][0]), &(s->rfreq[t][0]), 
+                                 alphaSize, 17 /*20*/ );
+   }
+
+
+   AssertH( nGroups < 8, 3002 );
+   AssertH( nSelectors < 32768 &&
+            nSelectors <= BZ_MAX_SELECTORS,
+            3003 );
+
+
+   /*--- Compute MTF values for the selectors. ---*/
+   {
+      UChar pos[BZ_N_GROUPS], ll_i, tmp2, tmp;
+      for (i = 0; i < nGroups; i++) pos[i] = i;
+      for (i = 0; i < nSelectors; i++) {
+         ll_i = s->selector[i];
+         j = 0;
+         tmp = pos[j];
+         while ( ll_i != tmp ) {
+            j++;
+            tmp2 = tmp;
+            tmp = pos[j];
+            pos[j] = tmp2;
+         };
+         pos[0] = tmp;
+         s->selectorMtf[i] = j;
+      }
+   };
+
+   /*--- Assign actual codes for the 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];
+      }
+      AssertH ( !(maxLen > 17 /*20*/ ), 3004 );
+      AssertH ( !(minLen < 1),  3005 );
+      BZ2_hbAssignCodes ( &(s->code[t][0]), &(s->len[t][0]), 
+                          minLen, maxLen, alphaSize );
+   }
+
+   /*--- Transmit the mapping table. ---*/
+   { 
+      Bool inUse16[16];
+      for (i = 0; i < 16; i++) {
+          inUse16[i] = False;
+          for (j = 0; j < 16; j++)
+             if (s->inUse[i * 16 + j]) inUse16[i] = True;
+      }
+     
+      nBytes = s->numZ;
+      for (i = 0; i < 16; i++)
+         if (inUse16[i]) bsW(s,1,1); else bsW(s,1,0);
+
+      for (i = 0; i < 16; i++)
+         if (inUse16[i])
+            for (j = 0; j < 16; j++) {
+               if (s->inUse[i * 16 + j]) bsW(s,1,1); else bsW(s,1,0);
+            }
+
+      if (s->verbosity >= 3) 
+         VPrintf1( "      bytes: mapping %d, ", s->numZ-nBytes );
+   }
+
+   /*--- Now the selectors. ---*/
+   nBytes = s->numZ;
+   bsW ( s, 3, nGroups );
+   bsW ( s, 15, nSelectors );
+   for (i = 0; i < nSelectors; i++) { 
+      for (j = 0; j < s->selectorMtf[i]; j++) bsW(s,1,1);
+      bsW(s,1,0);
+   }
+   if (s->verbosity >= 3)
+      VPrintf1( "selectors %d, ", s->numZ-nBytes );
+
+   /*--- Now the coding tables. ---*/
+   nBytes = s->numZ;
+
+   for (t = 0; t < nGroups; t++) {
+      Int32 curr = s->len[t][0];
+      bsW ( s, 5, curr );
+      for (i = 0; i < alphaSize; i++) {
+         while (curr < s->len[t][i]) { bsW(s,2,2); curr++; /* 10 */ };
+         while (curr > s->len[t][i]) { bsW(s,2,3); curr--; /* 11 */ };
+         bsW ( s, 1, 0 );
+      }
+   }
+
+   if (s->verbosity >= 3)
+      VPrintf1 ( "code lengths %d, ", s->numZ-nBytes );
+
+   /*--- And finally, the block data proper ---*/
+   nBytes = s->numZ;
+   selCtr = 0;
+   gs = 0;
+   while (True) {
+      if (gs >= s->nMTF) break;
+      ge = gs + BZ_G_SIZE - 1; 
+      if (ge >= s->nMTF) ge = s->nMTF-1;
+      AssertH ( s->selector[selCtr] < nGroups, 3006 );
+
+      if (nGroups == 6 && 50 == ge-gs+1) {
+            /*--- fast track the common case ---*/
+            UInt16 mtfv_i;
+            UChar* s_len_sel_selCtr 
+               = &(s->len[s->selector[selCtr]][0]);
+            Int32* s_code_sel_selCtr
+               = &(s->code[s->selector[selCtr]][0]);
+
+#           define BZ_ITAH(nn)                      \
+               mtfv_i = mtfv[gs+(nn)];              \
+               bsW ( s,                             \
+                     s_len_sel_selCtr[mtfv_i],      \
+                     s_code_sel_selCtr[mtfv_i] )
+
+            BZ_ITAH(0);  BZ_ITAH(1);  BZ_ITAH(2);  BZ_ITAH(3);  BZ_ITAH(4);
+            BZ_ITAH(5);  BZ_ITAH(6);  BZ_ITAH(7);  BZ_ITAH(8);  BZ_ITAH(9);
+            BZ_ITAH(10); BZ_ITAH(11); BZ_ITAH(12); BZ_ITAH(13); BZ_ITAH(14);
+            BZ_ITAH(15); BZ_ITAH(16); BZ_ITAH(17); BZ_ITAH(18); BZ_ITAH(19);
+            BZ_ITAH(20); BZ_ITAH(21); BZ_ITAH(22); BZ_ITAH(23); BZ_ITAH(24);
+            BZ_ITAH(25); BZ_ITAH(26); BZ_ITAH(27); BZ_ITAH(28); BZ_ITAH(29);
+            BZ_ITAH(30); BZ_ITAH(31); BZ_ITAH(32); BZ_ITAH(33); BZ_ITAH(34);
+            BZ_ITAH(35); BZ_ITAH(36); BZ_ITAH(37); BZ_ITAH(38); BZ_ITAH(39);
+            BZ_ITAH(40); BZ_ITAH(41); BZ_ITAH(42); BZ_ITAH(43); BZ_ITAH(44);
+            BZ_ITAH(45); BZ_ITAH(46); BZ_ITAH(47); BZ_ITAH(48); BZ_ITAH(49);
+
+#           undef BZ_ITAH
+
+      } else {
+	 /*--- slow version which correctly handles all situations ---*/
+         for (i = gs; i <= ge; i++) {
+            bsW ( s, 
+                  s->len  [s->selector[selCtr]] [mtfv[i]],
+                  s->code [s->selector[selCtr]] [mtfv[i]] );
+         }
+      }
+
+
+      gs = ge+1;
+      selCtr++;
+   }
+   AssertH( selCtr == nSelectors, 3007 );
+
+   if (s->verbosity >= 3)
+      VPrintf1( "codes %d\n", s->numZ-nBytes );
+}
+
+
+/*---------------------------------------------------*/
+void BZ2_compressBlock ( EState* s, Bool is_last_block )
+{
+   if (s->nblock > 0) {
+
+      BZ_FINALISE_CRC ( s->blockCRC );
+      s->combinedCRC = (s->combinedCRC << 1) | (s->combinedCRC >> 31);
+      s->combinedCRC ^= s->blockCRC;
+      if (s->blockNo > 1) s->numZ = 0;
+
+      if (s->verbosity >= 2)
+         VPrintf4( "    block %d: crc = 0x%08x, "
+                   "combined CRC = 0x%08x, size = %d\n",
+                   s->blockNo, s->blockCRC, s->combinedCRC, s->nblock );
+
+      BZ2_blockSort ( s );
+   }
+
+   s->zbits = (UChar*) (&((UChar*)s->arr2)[s->nblock]);
+
+   /*-- If this is the first block, create the stream header. --*/
+   if (s->blockNo == 1) {
+      BZ2_bsInitWrite ( s );
+      bsPutUChar ( s, BZ_HDR_B );
+      bsPutUChar ( s, BZ_HDR_Z );
+      bsPutUChar ( s, BZ_HDR_h );
+      bsPutUChar ( s, (UChar)(BZ_HDR_0 + s->blockSize100k) );
+   }
+
+   if (s->nblock > 0) {
+
+      bsPutUChar ( s, 0x31 ); bsPutUChar ( s, 0x41 );
+      bsPutUChar ( s, 0x59 ); bsPutUChar ( s, 0x26 );
+      bsPutUChar ( s, 0x53 ); bsPutUChar ( s, 0x59 );
+
+      /*-- Now the block's CRC, so it is in a known place. --*/
+      bsPutUInt32 ( s, s->blockCRC );
+
+      /*-- 
+         Now a single bit indicating (non-)randomisation. 
+         As of version 0.9.5, we use a better sorting algorithm
+         which makes randomisation unnecessary.  So always set
+         the randomised bit to 'no'.  Of course, the decoder
+         still needs to be able to handle randomised blocks
+         so as to maintain backwards compatibility with
+         older versions of bzip2.
+      --*/
+      bsW(s,1,0);
+
+      bsW ( s, 24, s->origPtr );
+      generateMTFValues ( s );
+      sendMTFValues ( s );
+   }
+
+
+   /*-- If this is the last block, add the stream trailer. --*/
+   if (is_last_block) {
+
+      bsPutUChar ( s, 0x17 ); bsPutUChar ( s, 0x72 );
+      bsPutUChar ( s, 0x45 ); bsPutUChar ( s, 0x38 );
+      bsPutUChar ( s, 0x50 ); bsPutUChar ( s, 0x90 );
+      bsPutUInt32 ( s, s->combinedCRC );
+      if (s->verbosity >= 2)
+         VPrintf1( "    final combined CRC = 0x%08x\n   ", s->combinedCRC );
+      bsFinishWrite ( s );
+   }
+}
+
+
+/*-------------------------------------------------------------*/
+/*--- end                                        compress.c ---*/
+/*-------------------------------------------------------------*/
diff --git a/cbits/crctable.c b/cbits/crctable.c
new file mode 100644
--- /dev/null
+++ b/cbits/crctable.c
@@ -0,0 +1,104 @@
+
+/*-------------------------------------------------------------*/
+/*--- Table for doing CRCs                                  ---*/
+/*---                                            crctable.c ---*/
+/*-------------------------------------------------------------*/
+
+/* ------------------------------------------------------------------
+   This file is part of bzip2/libbzip2, a program and library for
+   lossless, block-sorting data compression.
+
+   bzip2/libbzip2 version 1.0.8 of 13 July 2019
+   Copyright (C) 1996-2019 Julian Seward <jseward@acm.org>
+
+   Please read the WARNING, DISCLAIMER and PATENTS sections in the 
+   README file.
+
+   This program is released under the terms of the license contained
+   in the file LICENSE.
+   ------------------------------------------------------------------ */
+
+
+#include "bzlib_private.h"
+
+/*--
+  I think this is an implementation of the AUTODIN-II,
+  Ethernet & FDDI 32-bit CRC standard.  Vaguely derived
+  from code by Rob Warnock, in Section 51 of the
+  comp.compression FAQ.
+--*/
+
+UInt32 BZ2_crc32Table[256] = {
+
+   /*-- Ugly, innit? --*/
+
+   0x00000000L, 0x04c11db7L, 0x09823b6eL, 0x0d4326d9L,
+   0x130476dcL, 0x17c56b6bL, 0x1a864db2L, 0x1e475005L,
+   0x2608edb8L, 0x22c9f00fL, 0x2f8ad6d6L, 0x2b4bcb61L,
+   0x350c9b64L, 0x31cd86d3L, 0x3c8ea00aL, 0x384fbdbdL,
+   0x4c11db70L, 0x48d0c6c7L, 0x4593e01eL, 0x4152fda9L,
+   0x5f15adacL, 0x5bd4b01bL, 0x569796c2L, 0x52568b75L,
+   0x6a1936c8L, 0x6ed82b7fL, 0x639b0da6L, 0x675a1011L,
+   0x791d4014L, 0x7ddc5da3L, 0x709f7b7aL, 0x745e66cdL,
+   0x9823b6e0L, 0x9ce2ab57L, 0x91a18d8eL, 0x95609039L,
+   0x8b27c03cL, 0x8fe6dd8bL, 0x82a5fb52L, 0x8664e6e5L,
+   0xbe2b5b58L, 0xbaea46efL, 0xb7a96036L, 0xb3687d81L,
+   0xad2f2d84L, 0xa9ee3033L, 0xa4ad16eaL, 0xa06c0b5dL,
+   0xd4326d90L, 0xd0f37027L, 0xddb056feL, 0xd9714b49L,
+   0xc7361b4cL, 0xc3f706fbL, 0xceb42022L, 0xca753d95L,
+   0xf23a8028L, 0xf6fb9d9fL, 0xfbb8bb46L, 0xff79a6f1L,
+   0xe13ef6f4L, 0xe5ffeb43L, 0xe8bccd9aL, 0xec7dd02dL,
+   0x34867077L, 0x30476dc0L, 0x3d044b19L, 0x39c556aeL,
+   0x278206abL, 0x23431b1cL, 0x2e003dc5L, 0x2ac12072L,
+   0x128e9dcfL, 0x164f8078L, 0x1b0ca6a1L, 0x1fcdbb16L,
+   0x018aeb13L, 0x054bf6a4L, 0x0808d07dL, 0x0cc9cdcaL,
+   0x7897ab07L, 0x7c56b6b0L, 0x71159069L, 0x75d48ddeL,
+   0x6b93dddbL, 0x6f52c06cL, 0x6211e6b5L, 0x66d0fb02L,
+   0x5e9f46bfL, 0x5a5e5b08L, 0x571d7dd1L, 0x53dc6066L,
+   0x4d9b3063L, 0x495a2dd4L, 0x44190b0dL, 0x40d816baL,
+   0xaca5c697L, 0xa864db20L, 0xa527fdf9L, 0xa1e6e04eL,
+   0xbfa1b04bL, 0xbb60adfcL, 0xb6238b25L, 0xb2e29692L,
+   0x8aad2b2fL, 0x8e6c3698L, 0x832f1041L, 0x87ee0df6L,
+   0x99a95df3L, 0x9d684044L, 0x902b669dL, 0x94ea7b2aL,
+   0xe0b41de7L, 0xe4750050L, 0xe9362689L, 0xedf73b3eL,
+   0xf3b06b3bL, 0xf771768cL, 0xfa325055L, 0xfef34de2L,
+   0xc6bcf05fL, 0xc27dede8L, 0xcf3ecb31L, 0xcbffd686L,
+   0xd5b88683L, 0xd1799b34L, 0xdc3abdedL, 0xd8fba05aL,
+   0x690ce0eeL, 0x6dcdfd59L, 0x608edb80L, 0x644fc637L,
+   0x7a089632L, 0x7ec98b85L, 0x738aad5cL, 0x774bb0ebL,
+   0x4f040d56L, 0x4bc510e1L, 0x46863638L, 0x42472b8fL,
+   0x5c007b8aL, 0x58c1663dL, 0x558240e4L, 0x51435d53L,
+   0x251d3b9eL, 0x21dc2629L, 0x2c9f00f0L, 0x285e1d47L,
+   0x36194d42L, 0x32d850f5L, 0x3f9b762cL, 0x3b5a6b9bL,
+   0x0315d626L, 0x07d4cb91L, 0x0a97ed48L, 0x0e56f0ffL,
+   0x1011a0faL, 0x14d0bd4dL, 0x19939b94L, 0x1d528623L,
+   0xf12f560eL, 0xf5ee4bb9L, 0xf8ad6d60L, 0xfc6c70d7L,
+   0xe22b20d2L, 0xe6ea3d65L, 0xeba91bbcL, 0xef68060bL,
+   0xd727bbb6L, 0xd3e6a601L, 0xdea580d8L, 0xda649d6fL,
+   0xc423cd6aL, 0xc0e2d0ddL, 0xcda1f604L, 0xc960ebb3L,
+   0xbd3e8d7eL, 0xb9ff90c9L, 0xb4bcb610L, 0xb07daba7L,
+   0xae3afba2L, 0xaafbe615L, 0xa7b8c0ccL, 0xa379dd7bL,
+   0x9b3660c6L, 0x9ff77d71L, 0x92b45ba8L, 0x9675461fL,
+   0x8832161aL, 0x8cf30badL, 0x81b02d74L, 0x857130c3L,
+   0x5d8a9099L, 0x594b8d2eL, 0x5408abf7L, 0x50c9b640L,
+   0x4e8ee645L, 0x4a4ffbf2L, 0x470cdd2bL, 0x43cdc09cL,
+   0x7b827d21L, 0x7f436096L, 0x7200464fL, 0x76c15bf8L,
+   0x68860bfdL, 0x6c47164aL, 0x61043093L, 0x65c52d24L,
+   0x119b4be9L, 0x155a565eL, 0x18197087L, 0x1cd86d30L,
+   0x029f3d35L, 0x065e2082L, 0x0b1d065bL, 0x0fdc1becL,
+   0x3793a651L, 0x3352bbe6L, 0x3e119d3fL, 0x3ad08088L,
+   0x2497d08dL, 0x2056cd3aL, 0x2d15ebe3L, 0x29d4f654L,
+   0xc5a92679L, 0xc1683bceL, 0xcc2b1d17L, 0xc8ea00a0L,
+   0xd6ad50a5L, 0xd26c4d12L, 0xdf2f6bcbL, 0xdbee767cL,
+   0xe3a1cbc1L, 0xe760d676L, 0xea23f0afL, 0xeee2ed18L,
+   0xf0a5bd1dL, 0xf464a0aaL, 0xf9278673L, 0xfde69bc4L,
+   0x89b8fd09L, 0x8d79e0beL, 0x803ac667L, 0x84fbdbd0L,
+   0x9abc8bd5L, 0x9e7d9662L, 0x933eb0bbL, 0x97ffad0cL,
+   0xafb010b1L, 0xab710d06L, 0xa6322bdfL, 0xa2f33668L,
+   0xbcb4666dL, 0xb8757bdaL, 0xb5365d03L, 0xb1f740b4L
+};
+
+
+/*-------------------------------------------------------------*/
+/*--- end                                        crctable.c ---*/
+/*-------------------------------------------------------------*/
diff --git a/cbits/decompress.c b/cbits/decompress.c
new file mode 100644
--- /dev/null
+++ b/cbits/decompress.c
@@ -0,0 +1,652 @@
+
+/*-------------------------------------------------------------*/
+/*--- Decompression machinery                               ---*/
+/*---                                          decompress.c ---*/
+/*-------------------------------------------------------------*/
+
+/* ------------------------------------------------------------------
+   This file is part of bzip2/libbzip2, a program and library for
+   lossless, block-sorting data compression.
+
+   bzip2/libbzip2 version 1.0.8 of 13 July 2019
+   Copyright (C) 1996-2019 Julian Seward <jseward@acm.org>
+
+   Please read the WARNING, DISCLAIMER and PATENTS sections in the 
+   README file.
+
+   This program is released under the terms of the license contained
+   in the file LICENSE.
+   ------------------------------------------------------------------ */
+
+
+#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 > BZ_N_GROUPS) 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);
+         }
+         /* Having more than BZ_MAX_SELECTORS doesn't make much sense
+            since they will never be used, but some implementations might
+            "round up" the number of selectors, so just ignore those. */
+         if (i < BZ_MAX_SELECTORS)
+           s->selectorMtf[i] = j;
+      }
+      if (nSelectors > BZ_MAX_SELECTORS)
+        nSelectors = BZ_MAX_SELECTORS;
+
+      /*--- 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 {
+               /* Check that N doesn't get too big, so that es doesn't
+                  go negative.  The maximum value that can be
+                  RUNA/RUNB encoded is equal to the block size (post
+                  the initial RLE), viz, 900k, so bounding N at 2
+                  million should guard against overflow without
+                  rejecting any legitimate inputs. */
+               if (N >= 2*1024*1024) RETURN(BZ_DATA_ERROR);
+               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) --*/
+      /* Check: unzftab entries in range. */
+      for (i = 0; i <= 255; i++) {
+         if (s->unzftab[i] < 0 || s->unzftab[i] > nblock)
+            RETURN(BZ_DATA_ERROR);
+      }
+      /* Actually generate cftab. */
+      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];
+      /* Check: cftab entries in range. */
+      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);
+         }
+      }
+      /* Check: cftab entries non-descending. */
+      for (i = 1; i <= 256; i++) {
+         if (s->cftab[i-1] > s->cftab[i]) {
+            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 ---*/
+/*-------------------------------------------------------------*/
diff --git a/cbits/huffman.c b/cbits/huffman.c
new file mode 100644
--- /dev/null
+++ b/cbits/huffman.c
@@ -0,0 +1,205 @@
+
+/*-------------------------------------------------------------*/
+/*--- Huffman coding low-level stuff                        ---*/
+/*---                                             huffman.c ---*/
+/*-------------------------------------------------------------*/
+
+/* ------------------------------------------------------------------
+   This file is part of bzip2/libbzip2, a program and library for
+   lossless, block-sorting data compression.
+
+   bzip2/libbzip2 version 1.0.8 of 13 July 2019
+   Copyright (C) 1996-2019 Julian Seward <jseward@acm.org>
+
+   Please read the WARNING, DISCLAIMER and PATENTS sections in the 
+   README file.
+
+   This program is released under the terms of the license contained
+   in the file LICENSE.
+   ------------------------------------------------------------------ */
+
+
+#include "bzlib_private.h"
+
+/*---------------------------------------------------*/
+#define WEIGHTOF(zz0)  ((zz0) & 0xffffff00)
+#define DEPTHOF(zz1)   ((zz1) & 0x000000ff)
+#define MYMAX(zz2,zz3) ((zz2) > (zz3) ? (zz2) : (zz3))
+
+#define ADDWEIGHTS(zw1,zw2)                           \
+   (WEIGHTOF(zw1)+WEIGHTOF(zw2)) |                    \
+   (1 + MYMAX(DEPTHOF(zw1),DEPTHOF(zw2)))
+
+#define UPHEAP(z)                                     \
+{                                                     \
+   Int32 zz, tmp;                                     \
+   zz = z; tmp = heap[zz];                            \
+   while (weight[tmp] < weight[heap[zz >> 1]]) {      \
+      heap[zz] = heap[zz >> 1];                       \
+      zz >>= 1;                                       \
+   }                                                  \
+   heap[zz] = tmp;                                    \
+}
+
+#define DOWNHEAP(z)                                   \
+{                                                     \
+   Int32 zz, yy, tmp;                                 \
+   zz = z; tmp = heap[zz];                            \
+   while (True) {                                     \
+      yy = zz << 1;                                   \
+      if (yy > nHeap) break;                          \
+      if (yy < nHeap &&                               \
+          weight[heap[yy+1]] < weight[heap[yy]])      \
+         yy++;                                        \
+      if (weight[tmp] < weight[heap[yy]]) break;      \
+      heap[zz] = heap[yy];                            \
+      zz = yy;                                        \
+   }                                                  \
+   heap[zz] = tmp;                                    \
+}
+
+
+/*---------------------------------------------------*/
+void BZ2_hbMakeCodeLengths ( UChar *len, 
+                             Int32 *freq,
+                             Int32 alphaSize,
+                             Int32 maxLen )
+{
+   /*--
+      Nodes and heap entries run from 1.  Entry 0
+      for both the heap and nodes is a sentinel.
+   --*/
+   Int32 nNodes, nHeap, n1, n2, i, j, k;
+   Bool  tooLong;
+
+   Int32 heap   [ BZ_MAX_ALPHA_SIZE + 2 ];
+   Int32 weight [ BZ_MAX_ALPHA_SIZE * 2 ];
+   Int32 parent [ BZ_MAX_ALPHA_SIZE * 2 ]; 
+
+   for (i = 0; i < alphaSize; i++)
+      weight[i+1] = (freq[i] == 0 ? 1 : freq[i]) << 8;
+
+   while (True) {
+
+      nNodes = alphaSize;
+      nHeap = 0;
+
+      heap[0] = 0;
+      weight[0] = 0;
+      parent[0] = -2;
+
+      for (i = 1; i <= alphaSize; i++) {
+         parent[i] = -1;
+         nHeap++;
+         heap[nHeap] = i;
+         UPHEAP(nHeap);
+      }
+
+      AssertH( nHeap < (BZ_MAX_ALPHA_SIZE+2), 2001 );
+   
+      while (nHeap > 1) {
+         n1 = heap[1]; heap[1] = heap[nHeap]; nHeap--; DOWNHEAP(1);
+         n2 = heap[1]; heap[1] = heap[nHeap]; nHeap--; DOWNHEAP(1);
+         nNodes++;
+         parent[n1] = parent[n2] = nNodes;
+         weight[nNodes] = ADDWEIGHTS(weight[n1], weight[n2]);
+         parent[nNodes] = -1;
+         nHeap++;
+         heap[nHeap] = nNodes;
+         UPHEAP(nHeap);
+      }
+
+      AssertH( nNodes < (BZ_MAX_ALPHA_SIZE * 2), 2002 );
+
+      tooLong = False;
+      for (i = 1; i <= alphaSize; i++) {
+         j = 0;
+         k = i;
+         while (parent[k] >= 0) { k = parent[k]; j++; }
+         len[i-1] = j;
+         if (j > maxLen) tooLong = True;
+      }
+      
+      if (! tooLong) break;
+
+      /* 17 Oct 04: keep-going condition for the following loop used
+         to be 'i < alphaSize', which missed the last element,
+         theoretically leading to the possibility of the compressor
+         looping.  However, this count-scaling step is only needed if
+         one of the generated Huffman code words is longer than
+         maxLen, which up to and including version 1.0.2 was 20 bits,
+         which is extremely unlikely.  In version 1.0.3 maxLen was
+         changed to 17 bits, which has minimal effect on compression
+         ratio, but does mean this scaling step is used from time to
+         time, enough to verify that it works.
+
+         This means that bzip2-1.0.3 and later will only produce
+         Huffman codes with a maximum length of 17 bits.  However, in
+         order to preserve backwards compatibility with bitstreams
+         produced by versions pre-1.0.3, the decompressor must still
+         handle lengths of up to 20. */
+
+      for (i = 1; i <= alphaSize; i++) {
+         j = weight[i] >> 8;
+         j = 1 + (j / 2);
+         weight[i] = j << 8;
+      }
+   }
+}
+
+
+/*---------------------------------------------------*/
+void BZ2_hbAssignCodes ( Int32 *code,
+                         UChar *length,
+                         Int32 minLen,
+                         Int32 maxLen,
+                         Int32 alphaSize )
+{
+   Int32 n, vec, i;
+
+   vec = 0;
+   for (n = minLen; n <= maxLen; n++) {
+      for (i = 0; i < alphaSize; i++)
+         if (length[i] == n) { code[i] = vec; vec++; };
+      vec <<= 1;
+   }
+}
+
+
+/*---------------------------------------------------*/
+void BZ2_hbCreateDecodeTables ( Int32 *limit,
+                                Int32 *base,
+                                Int32 *perm,
+                                UChar *length,
+                                Int32 minLen,
+                                Int32 maxLen,
+                                Int32 alphaSize )
+{
+   Int32 pp, i, j, vec;
+
+   pp = 0;
+   for (i = minLen; i <= maxLen; i++)
+      for (j = 0; j < alphaSize; j++)
+         if (length[j] == i) { perm[pp] = j; pp++; };
+
+   for (i = 0; i < BZ_MAX_CODE_LEN; i++) base[i] = 0;
+   for (i = 0; i < alphaSize; i++) base[length[i]+1]++;
+
+   for (i = 1; i < BZ_MAX_CODE_LEN; i++) base[i] += base[i-1];
+
+   for (i = 0; i < BZ_MAX_CODE_LEN; i++) limit[i] = 0;
+   vec = 0;
+
+   for (i = minLen; i <= maxLen; i++) {
+      vec += (base[i+1] - base[i]);
+      limit[i] = vec-1;
+      vec <<= 1;
+   }
+   for (i = minLen + 1; i <= maxLen; i++)
+      base[i] = ((limit[i-1] + 1) << 1) - base[i];
+}
+
+
+/*-------------------------------------------------------------*/
+/*--- end                                         huffman.c ---*/
+/*-------------------------------------------------------------*/
diff --git a/cbits/randtable.c b/cbits/randtable.c
new file mode 100644
--- /dev/null
+++ b/cbits/randtable.c
@@ -0,0 +1,84 @@
+
+/*-------------------------------------------------------------*/
+/*--- Table for randomising repetitive blocks               ---*/
+/*---                                           randtable.c ---*/
+/*-------------------------------------------------------------*/
+
+/* ------------------------------------------------------------------
+   This file is part of bzip2/libbzip2, a program and library for
+   lossless, block-sorting data compression.
+
+   bzip2/libbzip2 version 1.0.8 of 13 July 2019
+   Copyright (C) 1996-2019 Julian Seward <jseward@acm.org>
+
+   Please read the WARNING, DISCLAIMER and PATENTS sections in the 
+   README file.
+
+   This program is released under the terms of the license contained
+   in the file LICENSE.
+   ------------------------------------------------------------------ */
+
+
+#include "bzlib_private.h"
+
+
+/*---------------------------------------------*/
+Int32 BZ2_rNums[512] = { 
+   619, 720, 127, 481, 931, 816, 813, 233, 566, 247, 
+   985, 724, 205, 454, 863, 491, 741, 242, 949, 214, 
+   733, 859, 335, 708, 621, 574, 73, 654, 730, 472, 
+   419, 436, 278, 496, 867, 210, 399, 680, 480, 51, 
+   878, 465, 811, 169, 869, 675, 611, 697, 867, 561, 
+   862, 687, 507, 283, 482, 129, 807, 591, 733, 623, 
+   150, 238, 59, 379, 684, 877, 625, 169, 643, 105, 
+   170, 607, 520, 932, 727, 476, 693, 425, 174, 647, 
+   73, 122, 335, 530, 442, 853, 695, 249, 445, 515, 
+   909, 545, 703, 919, 874, 474, 882, 500, 594, 612, 
+   641, 801, 220, 162, 819, 984, 589, 513, 495, 799, 
+   161, 604, 958, 533, 221, 400, 386, 867, 600, 782, 
+   382, 596, 414, 171, 516, 375, 682, 485, 911, 276, 
+   98, 553, 163, 354, 666, 933, 424, 341, 533, 870, 
+   227, 730, 475, 186, 263, 647, 537, 686, 600, 224, 
+   469, 68, 770, 919, 190, 373, 294, 822, 808, 206, 
+   184, 943, 795, 384, 383, 461, 404, 758, 839, 887, 
+   715, 67, 618, 276, 204, 918, 873, 777, 604, 560, 
+   951, 160, 578, 722, 79, 804, 96, 409, 713, 940, 
+   652, 934, 970, 447, 318, 353, 859, 672, 112, 785, 
+   645, 863, 803, 350, 139, 93, 354, 99, 820, 908, 
+   609, 772, 154, 274, 580, 184, 79, 626, 630, 742, 
+   653, 282, 762, 623, 680, 81, 927, 626, 789, 125, 
+   411, 521, 938, 300, 821, 78, 343, 175, 128, 250, 
+   170, 774, 972, 275, 999, 639, 495, 78, 352, 126, 
+   857, 956, 358, 619, 580, 124, 737, 594, 701, 612, 
+   669, 112, 134, 694, 363, 992, 809, 743, 168, 974, 
+   944, 375, 748, 52, 600, 747, 642, 182, 862, 81, 
+   344, 805, 988, 739, 511, 655, 814, 334, 249, 515, 
+   897, 955, 664, 981, 649, 113, 974, 459, 893, 228, 
+   433, 837, 553, 268, 926, 240, 102, 654, 459, 51, 
+   686, 754, 806, 760, 493, 403, 415, 394, 687, 700, 
+   946, 670, 656, 610, 738, 392, 760, 799, 887, 653, 
+   978, 321, 576, 617, 626, 502, 894, 679, 243, 440, 
+   680, 879, 194, 572, 640, 724, 926, 56, 204, 700, 
+   707, 151, 457, 449, 797, 195, 791, 558, 945, 679, 
+   297, 59, 87, 824, 713, 663, 412, 693, 342, 606, 
+   134, 108, 571, 364, 631, 212, 174, 643, 304, 329, 
+   343, 97, 430, 751, 497, 314, 983, 374, 822, 928, 
+   140, 206, 73, 263, 980, 736, 876, 478, 430, 305, 
+   170, 514, 364, 692, 829, 82, 855, 953, 676, 246, 
+   369, 970, 294, 750, 807, 827, 150, 790, 288, 923, 
+   804, 378, 215, 828, 592, 281, 565, 555, 710, 82, 
+   896, 831, 547, 261, 524, 462, 293, 465, 502, 56, 
+   661, 821, 976, 991, 658, 869, 905, 758, 745, 193, 
+   768, 550, 608, 933, 378, 286, 215, 979, 792, 961, 
+   61, 688, 793, 644, 986, 403, 106, 366, 905, 644, 
+   372, 567, 466, 434, 645, 210, 389, 550, 919, 135, 
+   780, 773, 635, 389, 707, 100, 626, 958, 165, 504, 
+   920, 176, 193, 713, 857, 265, 203, 50, 668, 108, 
+   645, 990, 626, 197, 510, 357, 358, 850, 858, 364, 
+   936, 638
+};
+
+
+/*-------------------------------------------------------------*/
+/*--- end                                       randtable.c ---*/
+/*-------------------------------------------------------------*/
diff --git a/src/Codec/Compression/BZip/Foreign.chs b/src/Codec/Compression/BZip/Foreign.chs
new file mode 100644
--- /dev/null
+++ b/src/Codec/Compression/BZip/Foreign.chs
@@ -0,0 +1,129 @@
+-- | This module uses exceptions behind the scenes
+--
+-- Consult the upstream [documentation](https://www.sourceware.org/bzip2/docs.html) for how to use this library.
+--
+-- For struct accessors, I recommend using [c2hs](http://hackage.haskell.org/package/c2hs).
+module Codec.Compression.BZip.Foreign ( -- * Types
+                                        BZAction (..)
+                                      , BZError (..)
+                                      , BzStream
+                                      , BzStreamPtr
+                                      , BzFile
+                                      , BzFilePtr
+                                      , FilePtr
+                                      -- * Low-level functions
+                                      , bZ2BzCompressInit
+                                      , bZ2BzCompress
+                                      , bZ2BzCompressEnd
+                                      , bZ2BzDecompressInit
+                                      , bZ2BzDecompress
+                                      , bZ2BzDecompressEnd
+                                      -- * High-level functions
+                                      , bZ2BzReadOpen
+                                      , bZ2BzReadClose
+                                      , bZ2BzReadGetUnused
+                                      , bZ2BzRead
+                                      , bZ2BzWriteOpen
+                                      , bZ2BzWrite
+                                      , bZ2BzWriteClose
+                                      , bZ2BzWriteClose64
+                                      -- * Macros
+                                      , bZMaxUnused
+                                      -- * Utility functions
+                                      , bZ2BzBuffToBuffCompress
+                                      , bZ2BzBuffToBuffDecompress
+                                      -- * Contributed functions
+                                      , bZ2BzlibVersion
+                                      ) where
+
+import Control.Applicative
+import Control.Exception (Exception, throw)
+import Control.Monad ((<=<))
+import Foreign.C.Types (CInt, CUInt)
+import Foreign.Marshal (alloca)
+import Foreign.Ptr (castPtr, Ptr)
+import Foreign.Storable (peek)
+
+#include <bzlib.h>
+
+{# enum define BZAction { BZ_RUN as BzRun
+                        , BZ_FLUSH as BzFlush
+                        , BZ_FINISH as BzFinish
+                        }
+  #}
+
+{# enum define BZError { BZ_OK as BzOk
+                       , BZ_RUN_OK as BzRunOk
+                       , BZ_FLUSH_OK as BzFlushOk
+                       , BZ_FINISH_OK as BzFinishOk
+                       , BZ_STREAM_END as BzStreamEnd
+                       , BZ_SEQUENCE_ERROR as BzSequenceError
+                       , BZ_PARAM_ERROR as BzParamError
+                       , BZ_MEM_ERROR as BzMemError
+                       , BZ_DATA_ERROR as BzDataError
+                       , BZ_DATA_ERROR_MAGIC as BzDataErrorMagic
+                       , BZ_IO_ERROR as BzIoError
+                       , BZ_UNEXPECTED_EOF as BzUnexpectedEof
+                       , BZ_OUTBUFF_FULL as BzOutbuffFull
+                       , BZ_CONFIG_ERROR as BzConfigError
+                       } deriving (Eq, Show)
+  #}
+
+instance Exception BZError where
+
+-- | Abstract type
+data BzStream
+
+-- | Abstract type
+data BzFile
+
+{#pointer *bz_stream as BzStreamPtr -> BzStream #}
+-- | @FILE*@ in C.
+{#pointer *FILE as FilePtr newtype #}
+{#pointer *BZFILE as BzFilePtr -> BzFile #}
+
+-- Low-level functions
+{# fun BZ2_bzCompressInit as ^ { `BzStreamPtr', `CInt', `CInt', `CInt' } -> `()' bzWrap*- #}
+{# fun BZ2_bzCompress as ^ { `BzStreamPtr', `BZAction' } -> `BZError' bzWrap* #}
+{# fun BZ2_bzCompressEnd as ^ { `BzStreamPtr' } -> `()' bzWrap*- #}
+{# fun BZ2_bzDecompressInit as ^ { `BzStreamPtr', `CInt', `Bool' } -> `()' bzWrap*- #}
+{# fun BZ2_bzDecompress as ^ { `BzStreamPtr' } -> `BZError' bzWrap* #}
+{# fun BZ2_bzDecompressEnd as ^ { `BzStreamPtr' } -> `()' bzWrap*- #}
+
+-- High-level functions
+{# fun BZ2_bzReadOpen as ^ { alloca- `BZError' peekBZError*, `FilePtr', `CInt', `Bool', castPtr `Ptr a', `CInt' } -> `BzFilePtr' #}
+{# fun BZ2_bzReadClose as ^ { alloca- `BZError' peekBZError*, `BzFilePtr' } -> `()' #}
+{# fun BZ2_bzReadGetUnused as ^ { alloca- `BZError' peekBZError*, `BzFilePtr', alloca- `Ptr a' peekVoidPtr*, alloca- `CInt' peek* } -> `()' #}
+{# fun BZ2_bzRead as ^ { alloca- `BZError' peekBZError*, `BzFilePtr', castPtr `Ptr a', `CInt' } -> `CInt' #}
+{# fun BZ2_bzWriteOpen as ^ { alloca- `BZError' peekBZError*, `FilePtr', `CInt', `CInt', `CInt' } -> `BzFilePtr' #}
+{# fun BZ2_bzWrite as ^ { alloca- `BZError' peekBZError*, `BzFilePtr', castPtr `Ptr a', `CInt' } -> `()' #}
+{# fun BZ2_bzWriteClose as ^ { alloca- `BZError' peekBZError*, `BzFilePtr', `Bool', alloca- `CUInt' peek*, alloca- `CUInt' peek* } -> `()' #}
+{# fun BZ2_bzWriteClose64 as ^ { alloca- `BZError' peekBZError*, `BzFilePtr', `Bool', alloca- `CUInt' peek*, alloca- `CUInt' peek*, alloca- `CUInt' peek*, alloca- `CUInt' peek* } -> `()' #}
+
+-- Macros
+bZMaxUnused :: Integral a => a
+bZMaxUnused = {# const BZ_MAX_UNUSED #}
+
+-- Utility functions
+{# fun BZ2_bzBuffToBuffCompress as ^ { castPtr `Ptr a', alloca- `CUInt' peek*, castPtr `Ptr a', `CUInt', `CInt', `CInt', `CInt' } -> `()' bzWrap*- #}
+{# fun BZ2_bzBuffToBuffDecompress as ^ { castPtr `Ptr a', alloca- `CUInt' peek*, castPtr `Ptr a', `CUInt', `Bool', `CInt' } -> `BZError' bzWrap* #}
+
+-- Contributed functions
+{# fun BZ2_bzlibVersion as ^ { } -> `String' #}
+
+peekVoidPtr :: Ptr (Ptr ()) -> IO (Ptr a)
+peekVoidPtr = fmap castPtr . peek
+
+peekBZError :: Ptr CInt -> IO BZError
+peekBZError = bzWrap <=< peek
+
+bzWrap :: CInt -> IO BZError
+bzWrap err =
+    let err' = toEnum (fromIntegral err) in
+    case err' of
+        BzOk        -> pure err'
+        BzRunOk     -> pure err'
+        BzFlushOk   -> pure err'
+        BzFinishOk  -> pure err'
+        BzStreamEnd -> pure err'
+        x           -> throw x
