A fix for zlib 1.1.4 that was supplied by Tim Yamin.cvs/bugfix-2.6.5

1 files changed, 422 insertions, 297 deletions

diff --git a/zlib/inftrees.c b/zlib/inftrees.c
index 8a9c13ff..28015112 100644
--- a/zlib/inftrees.c
+++ b/zlib/inftrees.c
@@ -1,329 +1,454 @@
 /* inftrees.c -- generate Huffman trees for efficient decoding
- * Copyright (C) 1995-2005 Mark Adler
- * For conditions of distribution and use, see copyright notice in zlib.h
+ * Copyright (C) 1995-2002 Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h 
  */
 
 #include "zutil.h"
 #include "inftrees.h"
 
-#define MAXBITS 15
+#if !defined(BUILDFIXED) && !defined(STDC)
+#  define BUILDFIXED   /* non ANSI compilers may not accept inffixed.h */
+#endif
 
 const char inflate_copyright[] =
-   " inflate 1.2.3 Copyright 1995-2005 Mark Adler ";
+   " inflate 1.1.4 Copyright 1995-2002 Mark Adler ";
 /*
   If you use the zlib library in a product, an acknowledgment is welcome
   in the documentation of your product. If for some reason you cannot
   include such an acknowledgment, I would appreciate that you keep this
   copyright string in the executable of your product.
  */
-
-/*
-   Build a set of tables to decode the provided canonical Huffman code.
-   The code lengths are lens[0..codes-1].  The result starts at *table,
-   whose indices are 0..2^bits-1.  work is a writable array of at least
-   lens shorts, which is used as a work area.  type is the type of code
-   to be generated, CODES, LENS, or DISTS.  On return, zero is success,
-   -1 is an invalid code, and +1 means that ENOUGH isn't enough.  table
-   on return points to the next available entry's address.  bits is the
-   requested root table index bits, and on return it is the actual root
-   table index bits.  It will differ if the request is greater than the
-   longest code or if it is less than the shortest code.
- */
-int inflate_table(type, lens, codes, table, bits, work)
-codetype type;
-unsigned short FAR *lens;
-unsigned codes;
-code FAR * FAR *table;
-unsigned FAR *bits;
-unsigned short FAR *work;
-{
-    unsigned len;               /* a code's length in bits */
-    unsigned sym;               /* index of code symbols */
-    unsigned min, max;          /* minimum and maximum code lengths */
-    unsigned root;              /* number of index bits for root table */
-    unsigned curr;              /* number of index bits for current table */
-    unsigned drop;              /* code bits to drop for sub-table */
-    int left;                   /* number of prefix codes available */
-    unsigned used;              /* code entries in table used */
-    unsigned huff;              /* Huffman code */
-    unsigned incr;              /* for incrementing code, index */
-    unsigned fill;              /* index for replicating entries */
-    unsigned low;               /* low bits for current root entry */
-    unsigned mask;              /* mask for low root bits */
-    code this;                  /* table entry for duplication */
-    code FAR *next;             /* next available space in table */
-    const unsigned short FAR *base;     /* base value table to use */
-    const unsigned short FAR *extra;    /* extra bits table to use */
-    int end;                    /* use base and extra for symbol > end */
-    unsigned short count[MAXBITS+1];    /* number of codes of each length */
-    unsigned short offs[MAXBITS+1];     /* offsets in table for each length */
-    static const unsigned short lbase[31] = { /* Length codes 257..285 base */
+struct internal_state  {int dummy;}; /* for buggy compilers */
+
+/* simplify the use of the inflate_huft type with some defines */
+#define exop word.what.Exop
+#define bits word.what.Bits
+
+
+local int huft_build OF((
+    uIntf *,            /* code lengths in bits */
+    uInt,               /* number of codes */
+    uInt,               /* number of "simple" codes */
+    const uIntf *,      /* list of base values for non-simple codes */
+    const uIntf *,      /* list of extra bits for non-simple codes */
+    inflate_huft * FAR*,/* result: starting table */
+    uIntf *,            /* maximum lookup bits (returns actual) */
+    inflate_huft *,     /* space for trees */
+    uInt *,             /* hufts used in space */
+    uIntf * ));         /* space for values */
+
+/* Tables for deflate from PKZIP's appnote.txt. */
+local const uInt cplens[31] = { /* 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};
-    static const unsigned short lext[31] = { /* Length codes 257..285 extra */
-        16, 16, 16, 16, 16, 16, 16, 16, 17, 17, 17, 17, 18, 18, 18, 18,
-        19, 19, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 16, 201, 196};
-    static const unsigned short dbase[32] = { /* Distance codes 0..29 base */
+        /* see note #13 above about 258 */
+local const uInt cplext[31] = { /* 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, 112, 112}; /* 112==invalid */
+local const uInt cpdist[30] = { /* 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, 0, 0};
-    static const unsigned short dext[32] = { /* Distance codes 0..29 extra */
-        16, 16, 16, 16, 17, 17, 18, 18, 19, 19, 20, 20, 21, 21, 22, 22,
-        23, 23, 24, 24, 25, 25, 26, 26, 27, 27,
-        28, 28, 29, 29, 64, 64};
-
-    /*
-       Process a set of code lengths to create a canonical Huffman code.  The
-       code lengths are lens[0..codes-1].  Each length corresponds to the
-       symbols 0..codes-1.  The Huffman code is generated by first sorting the
-       symbols by length from short to long, and retaining the symbol order
-       for codes with equal lengths.  Then the code starts with all zero bits
-       for the first code of the shortest length, and the codes are integer
-       increments for the same length, and zeros are appended as the length
-       increases.  For the deflate format, these bits are stored backwards
-       from their more natural integer increment ordering, and so when the
-       decoding tables are built in the large loop below, the integer codes
-       are incremented backwards.
-
-       This routine assumes, but does not check, that all of the entries in
-       lens[] are in the range 0..MAXBITS.  The caller must assure this.
-       1..MAXBITS is interpreted as that code length.  zero means that that
-       symbol does not occur in this code.
-
-       The codes are sorted by computing a count of codes for each length,
-       creating from that a table of starting indices for each length in the
-       sorted table, and then entering the symbols in order in the sorted
-       table.  The sorted table is work[], with that space being provided by
-       the caller.
-
-       The length counts are used for other purposes as well, i.e. finding
-       the minimum and maximum length codes, determining if there are any
-       codes at all, checking for a valid set of lengths, and looking ahead
-       at length counts to determine sub-table sizes when building the
-       decoding tables.
-     */
-
-    /* accumulate lengths for codes (assumes lens[] all in 0..MAXBITS) */
-    for (len = 0; len <= MAXBITS; len++)
-        count[len] = 0;
-    for (sym = 0; sym < codes; sym++)
-        count[lens[sym]]++;
-
-    /* bound code lengths, force root to be within code lengths */
-    root = *bits;
-    for (max = MAXBITS; max >= 1; max--)
-        if (count[max] != 0) break;
-    if (root > max) root = max;
-    if (max == 0) {                     /* no symbols to code at all */
-        this.op = (unsigned char)64;    /* invalid code marker */
-        this.bits = (unsigned char)1;
-        this.val = (unsigned short)0;
-        *(*table)++ = this;             /* make a table to force an error */
-        *(*table)++ = this;
-        *bits = 1;
-        return 0;     /* no symbols, but wait for decoding to report error */
-    }
-    for (min = 1; min <= MAXBITS; min++)
-        if (count[min] != 0) break;
-    if (root < min) root = min;
-
-    /* check for an over-subscribed or incomplete set of lengths */
-    left = 1;
-    for (len = 1; len <= MAXBITS; len++) {
-        left <<= 1;
-        left -= count[len];
-        if (left < 0) return -1;        /* over-subscribed */
-    }
-    if (left > 0 && (type == CODES || max != 1))
-        return -1;                      /* incomplete set */
-
-    /* generate offsets into symbol table for each length for sorting */
-    offs[1] = 0;
-    for (len = 1; len < MAXBITS; len++)
-        offs[len + 1] = offs[len] + count[len];
-
-    /* sort symbols by length, by symbol order within each length */
-    for (sym = 0; sym < codes; sym++)
-        if (lens[sym] != 0) work[offs[lens[sym]]++] = (unsigned short)sym;
-
-    /*
-       Create and fill in decoding tables.  In this loop, the table being
-       filled is at next and has curr index bits.  The code being used is huff
-       with length len.  That code is converted to an index by dropping drop
-       bits off of the bottom.  For codes where len is less than drop + curr,
-       those top drop + curr - len bits are incremented through all values to
-       fill the table with replicated entries.
-
-       root is the number of index bits for the root table.  When len exceeds
-       root, sub-tables are created pointed to by the root entry with an index
-       of the low root bits of huff.  This is saved in low to check for when a
-       new sub-table should be started.  drop is zero when the root table is
-       being filled, and drop is root when sub-tables are being filled.
-
-       When a new sub-table is needed, it is necessary to look ahead in the
-       code lengths to determine what size sub-table is needed.  The length
-       counts are used for this, and so count[] is decremented as codes are
-       entered in the tables.
-
-       used keeps track of how many table entries have been allocated from the
-       provided *table space.  It is checked when a LENS table is being made
-       against the space in *table, ENOUGH, minus the maximum space needed by
-       the worst case distance code, MAXD.  This should never happen, but the
-       sufficiency of ENOUGH has not been proven exhaustively, hence the check.
-       This assumes that when type == LENS, bits == 9.
-
-       sym increments through all symbols, and the loop terminates when
-       all codes of length max, i.e. all codes, have been processed.  This
-       routine permits incomplete codes, so another loop after this one fills
-       in the rest of the decoding tables with invalid code markers.
-     */
-
-    /* set up for code type */
-    switch (type) {
-    case CODES:
-        base = extra = work;    /* dummy value--not used */
-        end = 19;
-        break;
-    case LENS:
-        base = lbase;
-        base -= 257;
-        extra = lext;
-        extra -= 257;
-        end = 256;
-        break;
-    default:            /* DISTS */
-        base = dbase;
-        extra = dext;
-        end = -1;
-    }
+        8193, 12289, 16385, 24577};
+local const uInt cpdext[30] = { /* 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};
 
-    /* initialize state for loop */
-    huff = 0;                   /* starting code */
-    sym = 0;                    /* starting code symbol */
-    len = min;                  /* starting code length */
-    next = *table;              /* current table to fill in */
-    curr = root;                /* current table index bits */
-    drop = 0;                   /* current bits to drop from code for index */
-    low = (unsigned)(-1);       /* trigger new sub-table when len > root */
-    used = 1U << root;          /* use root table entries */
-    mask = used - 1;            /* mask for comparing low */
-
-    /* check available table space */
-    if (type == LENS && used >= ENOUGH - MAXD)
-        return 1;
-
-    /* process all codes and make table entries */
-    for (;;) {
-        /* create table entry */
-        this.bits = (unsigned char)(len - drop);
-        if ((int)(work[sym]) < end) {
-            this.op = (unsigned char)0;
-            this.val = work[sym];
-        }
-        else if ((int)(work[sym]) > end) {
-            this.op = (unsigned char)(extra[work[sym]]);
-            this.val = base[work[sym]];
-        }
-        else {
-            this.op = (unsigned char)(32 + 64);         /* end of block */
-            this.val = 0;
-        }
+/*
+   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.
+ */
 
-        /* replicate for those indices with low len bits equal to huff */
-        incr = 1U << (len - drop);
-        fill = 1U << curr;
-        min = fill;                 /* save offset to next table */
-        do {
-            fill -= incr;
-            next[(huff >> drop) + fill] = this;
-        } while (fill != 0);
-
-        /* backwards increment the len-bit code huff */
-        incr = 1U << (len - 1);
-        while (huff & incr)
-            incr >>= 1;
-        if (incr != 0) {
-            huff &= incr - 1;
-            huff += incr;
+
+/* If BMAX needs to be larger than 16, then h and x[] should be uLong. */
+#define BMAX 15         /* maximum bit length of any code */
+
+local int huft_build(b, n, s, d, e, t, m, hp, hn, v)
+uIntf *b;               /* code lengths in bits (all assumed <= BMAX) */
+uInt n;                 /* number of codes (assumed <= 288) */
+uInt s;                 /* number of simple-valued codes (0..s-1) */
+const uIntf *d;         /* list of base values for non-simple codes */
+const uIntf *e;         /* list of extra bits for non-simple codes */
+inflate_huft * FAR *t;  /* result: starting table */
+uIntf *m;               /* maximum lookup bits, returns actual */
+inflate_huft *hp;       /* space for trees */
+uInt *hn;               /* hufts used in space */
+uIntf *v;               /* working area: values in order of bit length */
+/* Given a list of code lengths and a maximum table size, make a set of
+   tables to decode that set of codes.  Return Z_OK on success, Z_BUF_ERROR
+   if the given code set is incomplete (the tables are still built in this
+   case), or Z_DATA_ERROR if the input is invalid. */
+{
+
+  uInt a;                       /* counter for codes of length k */
+  uInt c[BMAX+1];               /* bit length count table */
+  uInt f;                       /* i repeats in table every f entries */
+  int g;                        /* maximum code length */
+  int h;                        /* table level */
+  register uInt i;              /* counter, current code */
+  register uInt j;              /* counter */
+  register int k;               /* number of bits in current code */
+  int l;                        /* bits per table (returned in m) */
+  uInt mask;                    /* (1 << w) - 1, to avoid cc -O bug on HP */
+  register uIntf *p;            /* pointer into c[], b[], or v[] */
+  inflate_huft *q;              /* points to current table */
+  struct inflate_huft_s r;      /* table entry for structure assignment */
+  inflate_huft *u[BMAX];        /* table stack */
+  register int w;               /* bits before this table == (l * h) */
+  uInt x[BMAX+1];               /* bit offsets, then code stack */
+  uIntf *xp;                    /* pointer into x */
+  int y;                        /* number of dummy codes added */
+  uInt z;                       /* number of entries in current table */
+
+
+  /* Generate counts for each bit length */
+  p = c;
+#define C0 *p++ = 0;
+#define C2 C0 C0 C0 C0
+#define C4 C2 C2 C2 C2
+  C4                            /* clear c[]--assume BMAX+1 is 16 */
+  p = b;  i = n;
+  do {
+    c[*p++]++;                  /* assume all entries <= BMAX */
+  } while (--i);
+  if (c[0] == n)                /* null input--all zero length codes */
+  {
+    *t = (inflate_huft *)Z_NULL;
+    *m = 0;
+    return Z_DATA_ERROR;
+  }
+
+
+  /* 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 ((uInt)l < j)
+    l = j;
+  for (i = BMAX; i; i--)
+    if (c[i])
+      break;
+  g = i;                        /* maximum code length */
+  if ((uInt)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 Z_DATA_ERROR;
+  if ((y -= c[i]) < 0)
+    return Z_DATA_ERROR;
+  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);
+  n = x[g];                     /* set n to length of v */
+
+
+  /* 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] = (inflate_huft *)Z_NULL;        /* just to keep compilers happy */
+  q = (inflate_huft *)Z_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 = g - w;
+        z = z > (uInt)l ? (uInt)l : z;  /* table size upper limit */
+        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;
+          if (j < z)
+            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 new table */
+        if (*hn + z > MANY)     /* (note: doesn't matter for fixed) */
+          return Z_DATA_ERROR;  /* overflow of MANY */
+        u[h] = q = hp + *hn;
+        *hn += z;
+
+        /* connect to last table, if there is one */
+        if (h)
+        {
+          x[h] = i;             /* save pattern for backing up */
+          r.bits = (Byte)l;     /* bits to dump before this table */
+          r.exop = (Byte)j;     /* bits in this table */
+          j = i >> (w - l);
+          r.base = (uInt)(q - u[h-1] - j);   /* offset to this table */
+          u[h-1][j] = r;        /* connect to last table */
         }
         else
-            huff = 0;
+          *t = q;               /* first table is returned result */
+      }
+
+      /* set up table entry in r */
+      r.bits = (Byte)(k - w);
+      if (p >= v + n)
+        r.exop = 128 + 64;      /* out of values--invalid code */
+      else if (*p < s)
+      {
+        r.exop = (Byte)(*p < 256 ? 0 : 32 + 64);     /* 256 is end-of-block */
+        r.base = *p++;          /* simple code is just the value */
+      }
+      else
+      {
+        r.exop = (Byte)(e[*p - s] + 16 + 64);/* non-simple--look up in lists */
+        r.base = 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 */
+      mask = (1 << w) - 1;      /* needed on HP, cc -O bug */
+      while ((i & mask) != x[h])
+      {
+        h--;                    /* don't need to update q */
+        w -= l;
+        mask = (1 << w) - 1;
+      }
+    }
+  }
 
-        /* go to next symbol, update count, len */
-        sym++;
-        if (--(count[len]) == 0) {
-            if (len == max) break;
-            len = lens[work[sym]];
-        }
 
-        /* create new sub-table if needed */
-        if (len > root && (huff & mask) != low) {
-            /* if first time, transition to sub-tables */
-            if (drop == 0)
-                drop = root;
-
-            /* increment past last table */
-            next += min;            /* here min is 1 << curr */
-
-            /* determine length of next table */
-            curr = len - drop;
-            left = (int)(1 << curr);
-            while (curr + drop < max) {
-                left -= count[curr + drop];
-                if (left <= 0) break;
-                curr++;
-                left <<= 1;
-            }
+  /* Return Z_BUF_ERROR if we were given an incomplete table */
+  return y != 0 && g != 1 ? Z_BUF_ERROR : Z_OK;
+}
 
-            /* check for enough space */
-            used += 1U << curr;
-            if (type == LENS && used >= ENOUGH - MAXD)
-                return 1;
 
-            /* point entry in root table to sub-table */
-            low = huff & mask;
-            (*table)[low].op = (unsigned char)curr;
-            (*table)[low].bits = (unsigned char)root;
-            (*table)[low].val = (unsigned short)(next - *table);
-        }
-    }
+int inflate_trees_bits(c, bb, tb, hp, z)
+uIntf *c;               /* 19 code lengths */
+uIntf *bb;              /* bits tree desired/actual depth */
+inflate_huft * FAR *tb; /* bits tree result */
+inflate_huft *hp;       /* space for trees */
+z_streamp z;            /* for messages */
+{
+  int r;
+  uInt hn = 0;          /* hufts used in space */
+  uIntf *v;             /* work area for huft_build */
+
+  if ((v = (uIntf*)ZALLOC(z, 19, sizeof(uInt))) == Z_NULL)
+    return Z_MEM_ERROR;
+  r = huft_build(c, 19, 19, (uIntf*)Z_NULL, (uIntf*)Z_NULL,
+                 tb, bb, hp, &hn, v);
+  if (r == Z_DATA_ERROR)
+    z->msg = (char*)"oversubscribed dynamic bit lengths tree";
+  else if (r == Z_BUF_ERROR || *bb == 0)
+  {
+    z->msg = (char*)"incomplete dynamic bit lengths tree";
+    r = Z_DATA_ERROR;
+  }
+  ZFREE(z, v);
+  return r;
+}
 
-    /*
-       Fill in rest of table for incomplete codes.  This loop is similar to the
-       loop above in incrementing huff for table indices.  It is assumed that
-       len is equal to curr + drop, so there is no loop needed to increment
-       through high index bits.  When the current sub-table is filled, the loop
-       drops back to the root table to fill in any remaining entries there.
-     */
-    this.op = (unsigned char)64;                /* invalid code marker */
-    this.bits = (unsigned char)(len - drop);
-    this.val = (unsigned short)0;
-    while (huff != 0) {
-        /* when done with sub-table, drop back to root table */
-        if (drop != 0 && (huff & mask) != low) {
-            drop = 0;
-            len = root;
-            next = *table;
-            this.bits = (unsigned char)len;
-        }
 
-        /* put invalid code marker in table */
-        next[huff >> drop] = this;
+int inflate_trees_dynamic(nl, nd, c, bl, bd, tl, td, hp, z)
+uInt nl;                /* number of literal/length codes */
+uInt nd;                /* number of distance codes */
+uIntf *c;               /* that many (total) code lengths */
+uIntf *bl;              /* literal desired/actual bit depth */
+uIntf *bd;              /* distance desired/actual bit depth */
+inflate_huft * FAR *tl; /* literal/length tree result */
+inflate_huft * FAR *td; /* distance tree result */
+inflate_huft *hp;       /* space for trees */
+z_streamp z;            /* for messages */
+{
+  int r;
+  uInt hn = 0;          /* hufts used in space */
+  uIntf *v;             /* work area for huft_build */
+
+  /* allocate work area */
+  if ((v = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL)
+    return Z_MEM_ERROR;
+
+  /* build literal/length tree */
+  r = huft_build(c, nl, 257, cplens, cplext, tl, bl, hp, &hn, v);
+  if (r != Z_OK || *bl == 0)
+  {
+    if (r == Z_DATA_ERROR)
+      z->msg = (char*)"oversubscribed literal/length tree";
+    else if (r != Z_MEM_ERROR)
+    {
+      z->msg = (char*)"incomplete literal/length tree";
+      r = Z_DATA_ERROR;
+    }
+    ZFREE(z, v);
+    return r;
+  }
+
+  /* build distance tree */
+  r = huft_build(c + nl, nd, 0, cpdist, cpdext, td, bd, hp, &hn, v);
+  if (r != Z_OK || (*bd == 0 && nl > 257))
+  {
+    if (r == Z_DATA_ERROR)
+      z->msg = (char*)"oversubscribed distance tree";
+    else if (r == Z_BUF_ERROR) {
+#ifdef PKZIP_BUG_WORKAROUND
+      r = Z_OK;
+    }
+#else
+      z->msg = (char*)"incomplete distance tree";
+      r = Z_DATA_ERROR;
+    }
+    else if (r != Z_MEM_ERROR)
+    {
+      z->msg = (char*)"empty distance tree with lengths";
+      r = Z_DATA_ERROR;
+    }
+    ZFREE(z, v);
+    return r;
+#endif
+  }
+
+  /* done */
+  ZFREE(z, v);
+  return Z_OK;
+}
+
 
-        /* backwards increment the len-bit code huff */
-        incr = 1U << (len - 1);
-        while (huff & incr)
-            incr >>= 1;
-        if (incr != 0) {
-            huff &= incr - 1;
-            huff += incr;
-        }
-        else
-            huff = 0;
+/* build fixed tables only once--keep them here */
+#ifdef BUILDFIXED
+local int fixed_built = 0;
+#define FIXEDH 544      /* number of hufts used by fixed tables */
+local inflate_huft fixed_mem[FIXEDH];
+local uInt fixed_bl;
+local uInt fixed_bd;
+local inflate_huft *fixed_tl;
+local inflate_huft *fixed_td;
+#else
+#include "inffixed.h"
+#endif
+
+
+int inflate_trees_fixed(bl, bd, tl, td, z)
+uIntf *bl;               /* literal desired/actual bit depth */
+uIntf *bd;               /* distance desired/actual bit depth */
+inflate_huft * FAR *tl;  /* literal/length tree result */
+inflate_huft * FAR *td;  /* distance tree result */
+UNUSED(z_streamp z);     /* for memory allocation */
+{
+#ifdef BUILDFIXED
+  /* build fixed tables if not already */
+  if (!fixed_built)
+  {
+    int k;              /* temporary variable */
+    uInt f = 0;         /* number of hufts used in fixed_mem */
+    uIntf *c;           /* length list for huft_build */
+    uIntf *v;           /* work area for huft_build */
+
+    /* allocate memory */
+    if ((c = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL)
+      return Z_MEM_ERROR;
+    if ((v = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL)
+    {
+      ZFREE(z, c);
+      return Z_MEM_ERROR;
     }
 
-    /* set return parameters */
-    *table += used;
-    *bits = root;
-    return 0;
+    /* literal table */
+    for (k = 0; k < 144; k++)
+      c[k] = 8;
+    for (; k < 256; k++)
+      c[k] = 9;
+    for (; k < 280; k++)
+      c[k] = 7;
+    for (; k < 288; k++)
+      c[k] = 8;
+    fixed_bl = 9;
+    huft_build(c, 288, 257, cplens, cplext, &fixed_tl, &fixed_bl,
+               fixed_mem, &f, v);
+
+    /* distance table */
+    for (k = 0; k < 30; k++)
+      c[k] = 5;
+    fixed_bd = 5;
+    huft_build(c, 30, 0, cpdist, cpdext, &fixed_td, &fixed_bd,
+               fixed_mem, &f, v);
+
+    /* done */
+    ZFREE(z, v);
+    ZFREE(z, c);
+    fixed_built = 1;
+  }
+#endif
+  *bl = fixed_bl;
+  *bd = fixed_bd;
+  *tl = fixed_tl;
+  *td = fixed_td;
+  return Z_OK;
 }