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+/* inflate.c -- Not copyrighted 1992 by Mark Adler
+   version c10p1, 10 January 1993 */
+
+/* You can do whatever you like with this source file, though I would
+   prefer that if you modify it and redistribute it that you include
+   comments to that effect with your name and the date.  Thank you.
+   [The history has been moved to the file ChangeLog.]
+ */
+
+/*
+   Inflate deflated (PKZIP's method 8 compressed) data.  The compression
+   method searches for as much of the current string of bytes (up to a
+   length of 258) in the previous 32K bytes.  If it doesn't find any
+   matches (of at least length 3), it codes the next byte.  Otherwise, it
+   codes the length of the matched string and its distance backwards from
+   the current position.  There is a single Huffman code that codes both
+   single bytes (called "literals") and match lengths.  A second Huffman
+   code codes the distance information, which follows a length code.  Each
+   length or distance code actually represents a base value and a number
+   of "extra" (sometimes zero) bits to get to add to the base value.  At
+   the end of each deflated block is a special end-of-block (EOB) literal/
+   length code.  The decoding process is basically: get a literal/length
+   code; if EOB then done; if a literal, emit the decoded byte; if a
+   length then get the distance and emit the referred-to bytes from the
+   sliding window of previously emitted data.
+
+   There are (currently) three kinds of inflate blocks: stored, fixed, and
+   dynamic.  The compressor deals with some chunk of data at a time, and
+   decides which method to use on a chunk-by-chunk basis.  A chunk might
+   typically be 32K or 64K.  If the chunk is uncompressible, then the
+   "stored" method is used.  In this case, the bytes are simply stored as
+   is, eight bits per byte, with none of the above coding.  The bytes are
+   preceded by a count, since there is no longer an EOB code.
+
+   If the data is compressible, then either the fixed or dynamic methods
+   are used.  In the dynamic method, the compressed data is preceded by
+   an encoding of the literal/length and distance Huffman codes that are
+   to be used to decode this block.  The representation is itself Huffman
+   coded, and so is preceded by a description of that code.  These code
+   descriptions take up a little space, and so for small blocks, there is
+   a predefined set of codes, called the fixed codes.  The fixed method is
+   used if the block codes up smaller that way (usually for quite small
+   chunks), otherwise the dynamic method is used.  In the latter case, the
+   codes are customized to the probabilities in the current block, and so
+   can code it much better than the pre-determined fixed codes.
+ 
+   The Huffman codes themselves are decoded using a mutli-level table
+   lookup, in order to maximize the speed of decoding plus the speed of
+   building the decoding tables.  See the comments below that precede the
+   lbits and dbits tuning parameters.
+ */
+
+
+/*
+   Notes beyond the 1.93a appnote.txt:
+
+   1. Distance pointers never point before the beginning of the output
+      stream.
+   2. Distance pointers can point back across blocks, up to 32k away.
+   3. There is an implied maximum of 7 bits for the bit length table and
+      15 bits for the actual data.
+   4. If only one code exists, then it is encoded using one bit.  (Zero
+      would be more efficient, but perhaps a little confusing.)  If two
+      codes exist, they are coded using one bit each (0 and 1).
+   5. There is no way of sending zero distance codes--a dummy must be
+      sent if there are none.  (History: a pre 2.0 version of PKZIP would
+      store blocks with no distance codes, but this was discovered to be
+      too harsh a criterion.)  Valid only for 1.93a.  2.04c does allow
+      zero distance codes, which is sent as one code of zero bits in
+      length.
+   6. There are up to 286 literal/length codes.  Code 256 represents the
+      end-of-block.  Note however that the static length tree defines
+      288 codes just to fill out the Huffman codes.  Codes 286 and 287
+      cannot be used though, since there is no length base or extra bits
+      defined for them.  Similarly, there are up to 30 distance codes.
+      However, static trees define 32 codes (all 5 bits) to fill out the
+      Huffman codes, but the last two had better not show up in the data.
+   7. Unzip can check dynamic Huffman blocks for complete code sets.
+      The exception is that a single code would not be complete (see #4).
+   8. The five bits following the block type is really the number of
+      literal codes sent minus 257.
+   9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits
+      (1+6+6).  Therefore, to output three times the length, you output
+      three codes (1+1+1), whereas to output four times the same length,
+      you only need two codes (1+3).  Hmm.
+  10. In the tree reconstruction algorithm, Code = Code + Increment
+      only if BitLength(i) is not zero.  (Pretty obvious.)
+  11. Correction: 4 Bits: # of Bit Length codes - 4     (4 - 19)
+  12. Note: length code 284 can represent 227-258, but length code 285
+      really is 258.  The last length deserves its own, short code
+      since it gets used a lot in very redundant files.  The length
+      258 is special since 258 - 3 (the min match length) is 255.
+  13. The literal/length and distance code bit lengths are read as a
+      single stream of lengths.  It is possible (and advantageous) for
+      a repeat code (16, 17, or 18) to go across the boundary between
+      the two sets of lengths.
+ */
+
+#ifdef RCSID
+static char rcsid[] = "$Id: inflate.c,v 1.1 1994/12/14 04:31:21 roland Exp $";
+#endif
+
+#include <sys/types.h>
+
+#include "tailor.h"
+
+#if defined(STDC_HEADERS) || !defined(NO_STDLIB_H)
+#  include <stdlib.h>
+#endif
+
+#include "gzip.h"
+#define slide window
+
+/* Huffman code lookup table entry--this entry is four bytes for machines
+   that have 16-bit pointers (e.g. PC's in the small or medium model).
+   Valid extra bits are 0..13.  e == 15 is EOB (end of block), e == 16
+   means that v is a literal, 16 < e < 32 means that v is a pointer to
+   the next table, which codes e - 16 bits, and lastly e == 99 indicates
+   an unused code.  If a code with e == 99 is looked up, this implies an
+   error in the data. */
+struct huft {
+  uch e;                /* number of extra bits or operation */
+  uch b;                /* number of bits in this code or subcode */
+  union {
+    ush n;              /* literal, length base, or distance base */
+    struct huft *t;     /* pointer to next level of table */
+  } v;
+};
+
+
+/* Function prototypes */
+int huft_build OF((unsigned *, unsigned, unsigned, ush *, ush *,
+                   struct huft **, int *));
+int huft_free OF((struct huft *));
+int inflate_codes OF((struct huft *, struct huft *, int, int));
+int inflate_stored OF((void));
+int inflate_fixed OF((void));
+int inflate_dynamic OF((void));
+int inflate_block OF((int *));
+int inflate OF((void));
+
+
+/* The inflate algorithm uses a sliding 32K byte window on the uncompressed
+   stream to find repeated byte strings.  This is implemented here as a
+   circular buffer.  The index is updated simply by incrementing and then
+   and'ing with 0x7fff (32K-1). */
+/* It is left to other modules to supply the 32K area.  It is assumed
+   to be usable as if it were declared "uch slide[32768];" or as just
+   "uch *slide;" and then malloc'ed in the latter case.  The definition
+   must be in unzip.h, included above. */
+/* unsigned wp;             current position in slide */
+#define wp outcnt
+#define flush_output(w) (wp=(w),flush_window())
+
+/* Tables for deflate from PKZIP's appnote.txt. */
+static unsigned border[] = {    /* Order of the bit length code lengths */
+        16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
+static ush cplens[] = {         /* Copy lengths for literal codes 257..285 */
+        3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
+        35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
+        /* note: see note #13 above about the 258 in this list. */
+static ush cplext[] = {         /* Extra bits for literal codes 257..285 */
+        0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
+        3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 99, 99}; /* 99==invalid */
+static ush cpdist[] = {         /* Copy offsets for distance codes 0..29 */
+        1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
+        257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
+        8193, 12289, 16385, 24577};
+static ush cpdext[] = {         /* Extra bits for distance codes */
+        0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
+        7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
+        12, 12, 13, 13};
+
+
+
+/* Macros for inflate() bit peeking and grabbing.
+   The usage is:
+   
+        NEEDBITS(j)
+        x = b & mask_bits[j];
+        DUMPBITS(j)
+
+   where NEEDBITS makes sure that b has at least j bits in it, and
+   DUMPBITS removes the bits from b.  The macros use the variable k
+   for the number of bits in b.  Normally, b and k are register
+   variables for speed, and are initialized at the beginning of a
+   routine that uses these macros from a global bit buffer and count.
+
+   If we assume that EOB will be the longest code, then we will never
+   ask for bits with NEEDBITS that are beyond the end of the stream.
+   So, NEEDBITS should not read any more bytes than are needed to
+   meet the request.  Then no bytes need to be "returned" to the buffer
+   at the end of the last block.
+
+   However, this assumption is not true for fixed blocks--the EOB code
+   is 7 bits, but the other literal/length codes can be 8 or 9 bits.
+   (The EOB code is shorter than other codes because fixed blocks are
+   generally short.  So, while a block always has an EOB, many other
+   literal/length codes have a significantly lower probability of
+   showing up at all.)  However, by making the first table have a
+   lookup of seven bits, the EOB code will be found in that first
+   lookup, and so will not require that too many bits be pulled from
+   the stream.
+ */
+
+ulg bb;                         /* bit buffer */
+unsigned bk;                    /* bits in bit buffer */
+
+ush mask_bits[] = {
+    0x0000,
+    0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
+    0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
+};
+
+#ifdef CRYPT
+  uch cc;
+#  define NEXTBYTE() \
+     (decrypt ? (cc = get_byte(), zdecode(cc), cc) : get_byte())
+#else
+#  define NEXTBYTE()  (uch)get_byte()
+#endif
+#define NEEDBITS(n) {while(k<(n)){b|=((ulg)NEXTBYTE())<<k;k+=8;}}
+#define DUMPBITS(n) {b>>=(n);k-=(n);}
+
+
+/*
+   Huffman code decoding is performed using a multi-level table lookup.
+   The fastest way to decode is to simply build a lookup table whose
+   size is determined by the longest code.  However, the time it takes
+   to build this table can also be a factor if the data being decoded
+   is not very long.  The most common codes are necessarily the
+   shortest codes, so those codes dominate the decoding time, and hence
+   the speed.  The idea is you can have a shorter table that decodes the
+   shorter, more probable codes, and then point to subsidiary tables for
+   the longer codes.  The time it costs to decode the longer codes is
+   then traded against the time it takes to make longer tables.
+
+   This results of this trade are in the variables lbits and dbits
+   below.  lbits is the number of bits the first level table for literal/
+   length codes can decode in one step, and dbits is the same thing for
+   the distance codes.  Subsequent tables are also less than or equal to
+   those sizes.  These values may be adjusted either when all of the
+   codes are shorter than that, in which case the longest code length in
+   bits is used, or when the shortest code is *longer* than the requested
+   table size, in which case the length of the shortest code in bits is
+   used.
+
+   There are two different values for the two tables, since they code a
+   different number of possibilities each.  The literal/length table
+   codes 286 possible values, or in a flat code, a little over eight
+   bits.  The distance table codes 30 possible values, or a little less
+   than five bits, flat.  The optimum values for speed end up being
+   about one bit more than those, so lbits is 8+1 and dbits is 5+1.
+   The optimum values may differ though from machine to machine, and
+   possibly even between compilers.  Your mileage may vary.
+ */
+
+
+int lbits = 9;          /* bits in base literal/length lookup table */
+int dbits = 6;          /* bits in base distance lookup table */
+
+
+/* If BMAX needs to be larger than 16, then h and x[] should be ulg. */
+#define BMAX 16         /* maximum bit length of any code (16 for explode) */
+#define N_MAX 288       /* maximum number of codes in any set */
+
+
+unsigned hufts;         /* track memory usage */
+
+
+int huft_build(b, n, s, d, e, t, m)
+unsigned *b;            /* code lengths in bits (all assumed <= BMAX) */
+unsigned n;             /* number of codes (assumed <= N_MAX) */
+unsigned s;             /* number of simple-valued codes (0..s-1) */
+ush *d;                 /* list of base values for non-simple codes */
+ush *e;                 /* list of extra bits for non-simple codes */
+struct huft **t;        /* result: starting table */
+int *m;                 /* maximum lookup bits, returns actual */
+/* Given a list of code lengths and a maximum table size, make a set of
+   tables to decode that set of codes.  Return zero on success, one if
+   the given code set is incomplete (the tables are still built in this
+   case), two if the input is invalid (all zero length codes or an
+   oversubscribed set of lengths), and three if not enough memory. */
+{
+  unsigned a;                   /* counter for codes of length k */
+  unsigned c[BMAX+1];           /* bit length count table */
+  unsigned f;                   /* i repeats in table every f entries */
+  int g;                        /* maximum code length */
+  int h;                        /* table level */
+  register unsigned i;          /* counter, current code */
+  register unsigned j;          /* counter */
+  register int k;               /* number of bits in current code */
+  int l;                        /* bits per table (returned in m) */
+  register unsigned *p;         /* pointer into c[], b[], or v[] */
+  register struct huft *q;      /* points to current table */
+  struct huft r;                /* table entry for structure assignment */
+  struct huft *u[BMAX];         /* table stack */
+  unsigned v[N_MAX];            /* values in order of bit length */
+  register int w;               /* bits before this table == (l * h) */
+  unsigned x[BMAX+1];           /* bit offsets, then code stack */
+  unsigned *xp;                 /* pointer into x */
+  int y;                        /* number of dummy codes added */
+  unsigned z;                   /* number of entries in current table */
+
+
+  /* Generate counts for each bit length */
+  memzero(c, sizeof(c));
+  p = b;  i = n;
+  do {
+    Tracecv(*p, (stderr, (n-i >= ' ' && n-i <= '~' ? "%c %d\n" : "0x%x %d\n"), 
+	    n-i, *p));
+    c[*p]++;                    /* assume all entries <= BMAX */
+    p++;                      /* Can't combine with above line (Solaris bug) */
+  } while (--i);
+  if (c[0] == n)                /* null input--all zero length codes */
+  {
+    *t = (struct huft *)NULL;
+    *m = 0;
+    return 0;
+  }
+
+
+  /* Find minimum and maximum length, bound *m by those */
+  l = *m;
+  for (j = 1; j <= BMAX; j++)
+    if (c[j])
+      break;
+  k = j;                        /* minimum code length */
+  if ((unsigned)l < j)
+    l = j;
+  for (i = BMAX; i; i--)
+    if (c[i])
+      break;
+  g = i;                        /* maximum code length */
+  if ((unsigned)l > i)
+    l = i;
+  *m = l;
+
+
+  /* Adjust last length count to fill out codes, if needed */
+  for (y = 1 << j; j < i; j++, y <<= 1)
+    if ((y -= c[j]) < 0)
+      return 2;                 /* bad input: more codes than bits */
+  if ((y -= c[i]) < 0)
+    return 2;
+  c[i] += y;
+
+
+  /* Generate starting offsets into the value table for each length */
+  x[1] = j = 0;
+  p = c + 1;  xp = x + 2;
+  while (--i) {                 /* note that i == g from above */
+    *xp++ = (j += *p++);
+  }
+
+
+  /* Make a table of values in order of bit lengths */
+  p = b;  i = 0;
+  do {
+    if ((j = *p++) != 0)
+      v[x[j]++] = i;
+  } while (++i < n);
+
+
+  /* Generate the Huffman codes and for each, make the table entries */
+  x[0] = i = 0;                 /* first Huffman code is zero */
+  p = v;                        /* grab values in bit order */
+  h = -1;                       /* no tables yet--level -1 */
+  w = -l;                       /* bits decoded == (l * h) */
+  u[0] = (struct huft *)NULL;   /* just to keep compilers happy */
+  q = (struct huft *)NULL;      /* ditto */
+  z = 0;                        /* ditto */
+
+  /* go through the bit lengths (k already is bits in shortest code) */
+  for (; k <= g; k++)
+  {
+    a = c[k];
+    while (a--)
+    {
+      /* here i is the Huffman code of length k bits for value *p */
+      /* make tables up to required level */
+      while (k > w + l)
+      {
+        h++;
+        w += l;                 /* previous table always l bits */
+
+        /* compute minimum size table less than or equal to l bits */
+        z = (z = g - w) > (unsigned)l ? l : z;  /* upper limit on table size */
+        if ((f = 1 << (j = k - w)) > a + 1)     /* try a k-w bit table */
+        {                       /* too few codes for k-w bit table */
+          f -= a + 1;           /* deduct codes from patterns left */
+          xp = c + k;
+          while (++j < z)       /* try smaller tables up to z bits */
+          {
+            if ((f <<= 1) <= *++xp)
+              break;            /* enough codes to use up j bits */
+            f -= *xp;           /* else deduct codes from patterns */
+          }
+        }
+        z = 1 << j;             /* table entries for j-bit table */
+
+        /* allocate and link in new table */
+        if ((q = (struct huft *)malloc((z + 1)*sizeof(struct huft))) ==
+            (struct huft *)NULL)
+        {
+          if (h)
+            huft_free(u[0]);
+          return 3;             /* not enough memory */
+        }
+        hufts += z + 1;         /* track memory usage */
+        *t = q + 1;             /* link to list for huft_free() */
+        *(t = &(q->v.t)) = (struct huft *)NULL;
+        u[h] = ++q;             /* table starts after link */
+
+        /* connect to last table, if there is one */
+        if (h)
+        {
+          x[h] = i;             /* save pattern for backing up */
+          r.b = (uch)l;         /* bits to dump before this table */
+          r.e = (uch)(16 + j);  /* bits in this table */
+          r.v.t = q;            /* pointer to this table */
+          j = i >> (w - l);     /* (get around Turbo C bug) */
+          u[h-1][j] = r;        /* connect to last table */
+        }
+      }
+
+      /* set up table entry in r */
+      r.b = (uch)(k - w);
+      if (p >= v + n)
+        r.e = 99;               /* out of values--invalid code */
+      else if (*p < s)
+      {
+        r.e = (uch)(*p < 256 ? 16 : 15);    /* 256 is end-of-block code */
+        r.v.n = (ush)(*p);             /* simple code is just the value */
+	p++;                           /* one compiler does not like *p++ */
+      }
+      else
+      {
+        r.e = (uch)e[*p - s];   /* non-simple--look up in lists */
+        r.v.n = d[*p++ - s];
+      }
+
+      /* fill code-like entries with r */
+      f = 1 << (k - w);
+      for (j = i >> w; j < z; j += f)
+        q[j] = r;
+
+      /* backwards increment the k-bit code i */
+      for (j = 1 << (k - 1); i & j; j >>= 1)
+        i ^= j;
+      i ^= j;
+
+      /* backup over finished tables */
+      while ((i & ((1 << w) - 1)) != x[h])
+      {
+        h--;                    /* don't need to update q */
+        w -= l;
+      }
+    }
+  }
+
+
+  /* Return true (1) if we were given an incomplete table */
+  return y != 0 && g != 1;
+}
+
+
+
+int huft_free(t)
+struct huft *t;         /* table to free */
+/* Free the malloc'ed tables built by huft_build(), which makes a linked
+   list of the tables it made, with the links in a dummy first entry of
+   each table. */
+{
+  register struct huft *p, *q;
+
+
+  /* Go through linked list, freeing from the malloced (t[-1]) address. */
+  p = t;
+  while (p != (struct huft *)NULL)
+  {
+    q = (--p)->v.t;
+    free((char*)p);
+    p = q;
+  } 
+  return 0;
+}
+
+
+int inflate_codes(tl, td, bl, bd)
+struct huft *tl, *td;   /* literal/length and distance decoder tables */
+int bl, bd;             /* number of bits decoded by tl[] and td[] */
+/* inflate (decompress) the codes in a deflated (compressed) block.
+   Return an error code or zero if it all goes ok. */
+{
+  register unsigned e;  /* table entry flag/number of extra bits */
+  unsigned n, d;        /* length and index for copy */
+  unsigned w;           /* current window position */
+  struct huft *t;       /* pointer to table entry */
+  unsigned ml, md;      /* masks for bl and bd bits */
+  register ulg b;       /* bit buffer */
+  register unsigned k;  /* number of bits in bit buffer */
+
+
+  /* make local copies of globals */
+  b = bb;                       /* initialize bit buffer */
+  k = bk;
+  w = wp;                       /* initialize window position */
+
+  /* inflate the coded data */
+  ml = mask_bits[bl];           /* precompute masks for speed */
+  md = mask_bits[bd];
+  for (;;)                      /* do until end of block */
+  {
+    NEEDBITS((unsigned)bl)
+    if ((e = (t = tl + ((unsigned)b & ml))->e) > 16)
+      do {
+        if (e == 99)
+          return 1;
+        DUMPBITS(t->b)
+        e -= 16;
+        NEEDBITS(e)
+      } while ((e = (t = t->v.t + ((unsigned)b & mask_bits[e]))->e) > 16);
+    DUMPBITS(t->b)
+    if (e == 16)                /* then it's a literal */
+    {
+      slide[w++] = (uch)t->v.n;
+      Tracevv((stderr, "%c", slide[w-1]));
+      if (w == WSIZE)
+      {
+        flush_output(w);
+        w = 0;
+      }
+    }
+    else                        /* it's an EOB or a length */
+    {
+      /* exit if end of block */
+      if (e == 15)
+        break;
+
+      /* get length of block to copy */
+      NEEDBITS(e)
+      n = t->v.n + ((unsigned)b & mask_bits[e]);
+      DUMPBITS(e);
+
+      /* decode distance of block to copy */
+      NEEDBITS((unsigned)bd)
+      if ((e = (t = td + ((unsigned)b & md))->e) > 16)
+        do {
+          if (e == 99)
+            return 1;
+          DUMPBITS(t->b)
+          e -= 16;
+          NEEDBITS(e)
+        } while ((e = (t = t->v.t + ((unsigned)b & mask_bits[e]))->e) > 16);
+      DUMPBITS(t->b)
+      NEEDBITS(e)
+      d = w - t->v.n - ((unsigned)b & mask_bits[e]);
+      DUMPBITS(e)
+      Tracevv((stderr,"\\[%d,%d]", w-d, n));
+
+      /* do the copy */
+      do {
+        n -= (e = (e = WSIZE - ((d &= WSIZE-1) > w ? d : w)) > n ? n : e);
+#if !defined(NOMEMCPY) && !defined(DEBUG)
+        if (w - d >= e)         /* (this test assumes unsigned comparison) */
+        {
+          memcpy(slide + w, slide + d, e);
+          w += e;
+          d += e;
+        }
+        else                      /* do it slow to avoid memcpy() overlap */
+#endif /* !NOMEMCPY */
+          do {
+            slide[w++] = slide[d++];
+	    Tracevv((stderr, "%c", slide[w-1]));
+          } while (--e);
+        if (w == WSIZE)
+        {
+          flush_output(w);
+          w = 0;
+        }
+      } while (n);
+    }
+  }
+
+
+  /* restore the globals from the locals */
+  wp = w;                       /* restore global window pointer */
+  bb = b;                       /* restore global bit buffer */
+  bk = k;
+
+  /* done */
+  return 0;
+}
+
+
+
+int inflate_stored()
+/* "decompress" an inflated type 0 (stored) block. */
+{
+  unsigned n;           /* number of bytes in block */
+  unsigned w;           /* current window position */
+  register ulg b;       /* bit buffer */
+  register unsigned k;  /* number of bits in bit buffer */
+
+
+  /* make local copies of globals */
+  b = bb;                       /* initialize bit buffer */
+  k = bk;
+  w = wp;                       /* initialize window position */
+
+
+  /* go to byte boundary */
+  n = k & 7;
+  DUMPBITS(n);
+
+
+  /* get the length and its complement */
+  NEEDBITS(16)
+  n = ((unsigned)b & 0xffff);
+  DUMPBITS(16)
+  NEEDBITS(16)
+  if (n != (unsigned)((~b) & 0xffff))
+    return 1;                   /* error in compressed data */
+  DUMPBITS(16)
+
+
+  /* read and output the compressed data */
+  while (n--)
+  {
+    NEEDBITS(8)
+    slide[w++] = (uch)b;
+    if (w == WSIZE)
+    {
+      flush_output(w);
+      w = 0;
+    }
+    DUMPBITS(8)
+  }
+
+
+  /* restore the globals from the locals */
+  wp = w;                       /* restore global window pointer */
+  bb = b;                       /* restore global bit buffer */
+  bk = k;
+  return 0;
+}
+
+
+
+int inflate_fixed()
+/* decompress an inflated type 1 (fixed Huffman codes) block.  We should
+   either replace this with a custom decoder, or at least precompute the
+   Huffman tables. */
+{
+  int i;                /* temporary variable */
+  struct huft *tl;      /* literal/length code table */
+  struct huft *td;      /* distance code table */
+  int bl;               /* lookup bits for tl */
+  int bd;               /* lookup bits for td */
+  unsigned l[288];      /* length list for huft_build */
+
+
+  /* set up literal table */
+  for (i = 0; i < 144; i++)
+    l[i] = 8;
+  for (; i < 256; i++)
+    l[i] = 9;
+  for (; i < 280; i++)
+    l[i] = 7;
+  for (; i < 288; i++)          /* make a complete, but wrong code set */
+    l[i] = 8;
+  bl = 7;
+  if ((i = huft_build(l, 288, 257, cplens, cplext, &tl, &bl)) != 0)
+    return i;
+
+
+  /* set up distance table */
+  for (i = 0; i < 30; i++)      /* make an incomplete code set */
+    l[i] = 5;
+  bd = 5;
+  if ((i = huft_build(l, 30, 0, cpdist, cpdext, &td, &bd)) > 1)
+  {
+    huft_free(tl);
+    return i;
+  }
+
+
+  /* decompress until an end-of-block code */
+  if (inflate_codes(tl, td, bl, bd))
+    return 1;
+
+
+  /* free the decoding tables, return */
+  huft_free(tl);
+  huft_free(td);
+  return 0;
+}
+
+
+
+int inflate_dynamic()
+/* decompress an inflated type 2 (dynamic Huffman codes) block. */
+{
+  int i;                /* temporary variables */
+  unsigned j;
+  unsigned l;           /* last length */
+  unsigned m;           /* mask for bit lengths table */
+  unsigned n;           /* number of lengths to get */
+  struct huft *tl;      /* literal/length code table */
+  struct huft *td;      /* distance code table */
+  int bl;               /* lookup bits for tl */
+  int bd;               /* lookup bits for td */
+  unsigned nb;          /* number of bit length codes */
+  unsigned nl;          /* number of literal/length codes */
+  unsigned nd;          /* number of distance codes */
+#ifdef PKZIP_BUG_WORKAROUND
+  unsigned ll[288+32];  /* literal/length and distance code lengths */
+#else
+  unsigned ll[286+30];  /* literal/length and distance code lengths */
+#endif
+  register ulg b;       /* bit buffer */
+  register unsigned k;  /* number of bits in bit buffer */
+
+
+  /* make local bit buffer */
+  b = bb;
+  k = bk;
+
+
+  /* read in table lengths */
+  NEEDBITS(5)
+  nl = 257 + ((unsigned)b & 0x1f);      /* number of literal/length codes */
+  DUMPBITS(5)
+  NEEDBITS(5)
+  nd = 1 + ((unsigned)b & 0x1f);        /* number of distance codes */
+  DUMPBITS(5)
+  NEEDBITS(4)
+  nb = 4 + ((unsigned)b & 0xf);         /* number of bit length codes */
+  DUMPBITS(4)
+#ifdef PKZIP_BUG_WORKAROUND
+  if (nl > 288 || nd > 32)
+#else
+  if (nl > 286 || nd > 30)
+#endif
+    return 1;                   /* bad lengths */
+
+
+  /* read in bit-length-code lengths */
+  for (j = 0; j < nb; j++)
+  {
+    NEEDBITS(3)
+    ll[border[j]] = (unsigned)b & 7;
+    DUMPBITS(3)
+  }
+  for (; j < 19; j++)
+    ll[border[j]] = 0;
+
+
+  /* build decoding table for trees--single level, 7 bit lookup */
+  bl = 7;
+  if ((i = huft_build(ll, 19, 19, NULL, NULL, &tl, &bl)) != 0)
+  {
+    if (i == 1)
+      huft_free(tl);
+    return i;                   /* incomplete code set */
+  }
+
+
+  /* read in literal and distance code lengths */
+  n = nl + nd;
+  m = mask_bits[bl];
+  i = l = 0;
+  while ((unsigned)i < n)
+  {
+    NEEDBITS((unsigned)bl)
+    j = (td = tl + ((unsigned)b & m))->b;
+    DUMPBITS(j)
+    j = td->v.n;
+    if (j < 16)                 /* length of code in bits (0..15) */
+      ll[i++] = l = j;          /* save last length in l */
+    else if (j == 16)           /* repeat last length 3 to 6 times */
+    {
+      NEEDBITS(2)
+      j = 3 + ((unsigned)b & 3);
+      DUMPBITS(2)
+      if ((unsigned)i + j > n)
+        return 1;
+      while (j--)
+        ll[i++] = l;
+    }
+    else if (j == 17)           /* 3 to 10 zero length codes */
+    {
+      NEEDBITS(3)
+      j = 3 + ((unsigned)b & 7);
+      DUMPBITS(3)
+      if ((unsigned)i + j > n)
+        return 1;
+      while (j--)
+        ll[i++] = 0;
+      l = 0;
+    }
+    else                        /* j == 18: 11 to 138 zero length codes */
+    {
+      NEEDBITS(7)
+      j = 11 + ((unsigned)b & 0x7f);
+      DUMPBITS(7)
+      if ((unsigned)i + j > n)
+        return 1;
+      while (j--)
+        ll[i++] = 0;
+      l = 0;
+    }
+  }
+
+
+  /* free decoding table for trees */
+  huft_free(tl);
+
+
+  /* restore the global bit buffer */
+  bb = b;
+  bk = k;
+
+
+  /* build the decoding tables for literal/length and distance codes */
+  bl = lbits;
+  if ((i = huft_build(ll, nl, 257, cplens, cplext, &tl, &bl)) != 0)
+  {
+    if (i == 1) {
+      fprintf(stderr, " incomplete literal tree\n");
+      huft_free(tl);
+    }
+    return i;                   /* incomplete code set */
+  }
+  bd = dbits;
+  if ((i = huft_build(ll + nl, nd, 0, cpdist, cpdext, &td, &bd)) != 0)
+  {
+    if (i == 1) {
+      fprintf(stderr, " incomplete distance tree\n");
+#ifdef PKZIP_BUG_WORKAROUND
+      i = 0;
+    }
+#else
+      huft_free(td);
+    }
+    huft_free(tl);
+    return i;                   /* incomplete code set */
+#endif
+  }
+
+
+  /* decompress until an end-of-block code */
+  if (inflate_codes(tl, td, bl, bd))
+    return 1;
+
+
+  /* free the decoding tables, return */
+  huft_free(tl);
+  huft_free(td);
+  return 0;
+}
+
+
+
+int inflate_block(e)
+int *e;                 /* last block flag */
+/* decompress an inflated block */
+{
+  unsigned t;           /* block type */
+  register ulg b;       /* bit buffer */
+  register unsigned k;  /* number of bits in bit buffer */
+
+
+  /* make local bit buffer */
+  b = bb;
+  k = bk;
+
+
+  /* read in last block bit */
+  NEEDBITS(1)
+  *e = (int)b & 1;
+  DUMPBITS(1)
+
+
+  /* read in block type */
+  NEEDBITS(2)
+  t = (unsigned)b & 3;
+  DUMPBITS(2)
+
+
+  /* restore the global bit buffer */
+  bb = b;
+  bk = k;
+
+
+  /* inflate that block type */
+  if (t == 2)
+    return inflate_dynamic();
+  if (t == 0)
+    return inflate_stored();
+  if (t == 1)
+    return inflate_fixed();
+
+
+  /* bad block type */
+  return 2;
+}
+
+
+
+int inflate()
+/* decompress an inflated entry */
+{
+  int e;                /* last block flag */
+  int r;                /* result code */
+  unsigned h;           /* maximum struct huft's malloc'ed */
+
+
+  /* initialize window, bit buffer */
+  wp = 0;
+  bk = 0;
+  bb = 0;
+
+
+  /* decompress until the last block */
+  h = 0;
+  do {
+    hufts = 0;
+    if ((r = inflate_block(&e)) != 0)
+      return r;
+    if (hufts > h)
+      h = hufts;
+  } while (!e);
+
+  /* Undo too much lookahead. The next read will be byte aligned so we
+   * can discard unused bits in the last meaningful byte.
+   */
+  while (bk >= 8) {
+    bk -= 8;
+    inptr--;
+  }
+
+  /* flush out slide */
+  flush_output(wp);
+
+
+  /* return success */
+#ifdef DEBUG
+  fprintf(stderr, "<%u> ", h);
+#endif /* DEBUG */
+  return 0;
+}