patch-2.4.20 linux-2.4.20/fs/inflate_fs/inftrees.c

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diff -urN linux-2.4.19/fs/inflate_fs/inftrees.c linux-2.4.20/fs/inflate_fs/inftrees.c
@@ -1,391 +0,0 @@
-/* inftrees.c -- generate Huffman trees for efficient decoding
- * Copyright (C) 1995-1998 Mark Adler
- * For conditions of distribution and use, see copyright notice in zlib.h 
- */
-
-#include "zutil.h"
-#include "inftrees.h"
-#include "infutil.h"
-
-static const char inflate_copyright[] =
-   " inflate 1.1.3 Copyright 1995-1998 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.
- */
-struct internal_state;
-
-/* 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};
-        /* 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};
-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};
-
-/*
-   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.
- */
-
-
-/* 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), Z_DATA_ERROR if the input is invalid (an over-subscribed set of
-   lengths), or Z_MEM_ERROR if not enough memory. */
-{
-
-  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_OK;
-  }
-
-
-  /* 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 ? 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_MEM_ERROR;   /* not enough memory */
-        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
-          *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;
-      }
-    }
-  }
-
-
-  /* Return Z_BUF_ERROR if we were given an incomplete table */
-  return y != 0 && g != 1 ? Z_BUF_ERROR : Z_OK;
-}
-
-
-int zlib_fs_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 */
-  
-  v = WS(z)->tree_work_area_1;
-  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;
-  }
-  return r;
-}
-
-int zlib_fs_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 */
-  v = WS(z)->tree_work_area_2;
-
-  /* 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;
-    }
-    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;
-    }
-    return r;
-#endif
-  }
-
-  /* done */
-  return Z_OK;
-}
-
-
-/* build fixed tables only once--keep them here */
-#include "inffixed.h"
-
-
-int zlib_fs_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 */
-z_streamp z;             /* for memory allocation */
-{
-  *bl = fixed_bl;
-  *bd = fixed_bd;
-  *tl = fixed_tl;
-  *td = fixed_td;
-  return Z_OK;
-}

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