"

 COPYRIGHT (c) 1998 by eXept Software AG

	      All Rights Reserved

 This software is furnished under a license and may be used

 only in accordance with the terms of that license and with the

 inclusion of the above copyright notice.   This software may not

 be provided or otherwise made available to, or used by, any

 other person.  No title to or ownership of the software is

 hereby transferred.

"

"{ Package: 'stx:libbasic2' }"

Object subclass:#ZipArchive

	instanceVariableNames:'file mode archiveName firstEntry lastEntry

	classVariableNames:'RecentlyUsedZipArchives FlushBlock ECREC_SIZE LREC_SIZE CREC_SIZE

		SIZE_CENTRAL_DIRECTORY TOTAL_ENTRIES_CENTRAL_DIR

		C_COMPRESSED_SIZE C_RELATIVE_OFFSET_LOCAL_HEADER

		C_FILENAME_LENGTH C_UNCOMPRESSED_SIZE C_CENTRALHEADERSIGNATURE

		C_LOCALHEADERSIGNATURE C_CENTRALENDSIGNATURE

		ZipFileFormatErrorSignal COMPR_STORED COMPR_SHRUNK COMPR_REDUCED1

		COMPR_REDUCED2 COMPR_REDUCED3 COMPR_REDUCED4 COMPR_IMPLODED

		COMPR_TOKENIZED COMPR_DEFLATED'

	poolDictionaries:''

	category:'System-Support-FileFormats'

!

Object subclass:#ZipMember

	classVariableNames:''

	poolDictionaries:''

	privateIn:ZipArchive

!

!ZipArchive primitiveDefinitions!

%{

#include <stdio.h>

#define uchar     unsigned char

#define ushort    unsigned short

#define ulong     unsigned long

/*

 * inflate definitions

 */

#define PKZIP_BUG_WORKAROUND    /* PKZIP 1.93a problem--live with it */

#ifndef WSIZE           /* default is 32K */

# define WSIZE 0x8000   /* window size--must be a power of two, and at least */

#endif                  /* 32K for zip's deflate method */

#define NEXTBYTE        (*inPtr++)

#define XXXFLUSH(n)        slide += (n)

#define FLUSH(n)        { bcopy(slide, outPtr, (n)); outPtr += (n); }

#ifdef DEBUG

# define Trace(x)       if (debugTrace) { console_fprintf x ; }

#else

# define Trace(x)       /* nothing */

#endif

/* 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 {

  uchar e;                /* number of extra bits or operation */

  uchar b;                /* number of bits in this code or subcode */

  union {

    ushort n;             /* literal, length base, or distance base */

    struct huft *t;       /* pointer to next level of table */

  } v;

};

%}

! !

!ZipArchive primitiveVariables!

%{

static int debugTrace = 0;

/*

 * inflate variables

 */

static unsigned char *inPtr;

static unsigned char *outPtr;

static unsigned char *slide;

static int qflag = 0;

/* 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 "uchar slide[32768];" or as just

   "uchar *slide;" and then malloc'ed in the latter case.  The definition

   must be in unzip.h, included above. */

static unsigned wp;            /* current position in slide */

/* 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 ushort 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 ushort 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 ushort 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 ushort 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};

/* And'ing with mask[n] masks the lower n bits */

static ushort mask[] = {

    0x0000,

    0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,

    0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff

};

/* Macros for inflate() bit peeking and grabbing.

   The usage is:

	NEEDBITS(j)

	x = b & mask[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 begining of a

   routine that uses these macros from a global bit buffer and count.

   In order to not ask for more bits than there are in the compressed

   stream, the Huffman tables are constructed to only ask for just

   enough bits to make up the end-of-block code (value 256).  Then no

   bytes need to be "returned" to the buffer at the end of the last

   block.  See the huft_build() routine.

 */

static ulong bb;                       /* bit buffer */

static unsigned bk;                    /* bits in bit buffer */

#define NEEDBITS(n) { while(k<(n)){ b |= ((ulong)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.

 */

static int lbits = 9;          /* bits in base literal/length lookup table */

static int dbits = 6;          /* bits in base distance lookup table */

/* If BMAX needs to be larger than 16, then h and x[] should be ulong. */

#define BMAX 16         /* maximum bit length of any code (16 for explode) */

#define N_MAX 288       /* maximum number of codes in any set */

static unsigned hufts;         /* track memory usage */

%}

! !

!ZipArchive primitiveFunctions!

%{

/*

 * inflate algorithm

 */

/* 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. */

static int

huft_free(t)

    struct huft *t;         /* table to free */

{

  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(p);

    p = q;

  }

  return 0;

}

/* 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.

   The code with value 256 is special, and the tables are constructed

   so that no bits beyond that code are fetched when that code is

   decoded. */

static 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) */

    ushort *d;              /* list of base values for non-simple codes */

    ushort *e;              /* list of extra bits for non-simple codes */

    struct huft **t;        /* result: starting table */

    int *m;                 /* maximum lookup bits, returns actual */

{

  unsigned a;                   /* counter for codes of length k */

  unsigned c[BMAX+1];           /* bit length count table */

  unsigned el;                  /* length of EOB code (value 256) */

  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 lx[BMAX+1];               /* memory for l[-1..BMAX-1] */

  int *l = lx+1;                /* stack of bits per table */

  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 */

  static 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 */

  extern void *malloc();

  /* Generate counts for each bit length */

  el = n > 256 ? b[256] : BMAX; /* set length of EOB code, if any */

  bzero((char *)c, sizeof(c));

  p = b;  i = n;

  do {

    c[*p]++; p++;               /* assume all entries <= BMAX */

  } 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 */

  for (j = 1; j <= BMAX; j++)

    if (c[j])

      break;

  k = j;                        /* minimum code length */

  if ((unsigned)*m < j)

    *m = j;

  for (i = BMAX; i; i--)

    if (c[i])

      break;

  g = i;                        /* maximum code length */

  if ((unsigned)*m > i)

    *m = i;

  /* 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[-1] = 0;                /* no bits decoded yet */

  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[h++];            /* add bits already decoded */

	/* compute minimum size table less than or equal to *m bits */

	z = (z = g - w) > (unsigned)*m ? *m : z;        /* 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;

	  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 */

	  }

	}

	if ((unsigned)w + j > el && (unsigned)w < el)

	  j = el - w;           /* make EOB code end at table */

	z = 1 << j;             /* table entries for j-bit table */

	l[h] = j;               /* set table size in stack */

	/* 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 = (uchar)l[h-1];    /* bits to dump before this table */

	  r.e = (uchar)(16 + j);  /* bits in this table */

	  r.v.t = q;            /* pointer to this table */

	  j = (i & ((1 << w) - 1)) >> (w - l[h-1]);

	  u[h-1][j] = r;        /* connect to last table */

	}

      }

      /* set up table entry in r */

      r.b = (uchar)(k - w);

      if (p >= v + n)

	r.e = 99;               /* out of values--invalid code */

      else if (*p < s)

      {

	r.e = (uchar)(*p < 256 ? 16 : 15);    /* 256 is end-of-block code */

	r.v.n = *p++;           /* simple code is just the value */

      }

      else

      {

	r.e = (uchar)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])

	w -= l[--h];            /* don't need to update q */

    }

  }

  /* return actual size of base table */

  *m = l[0];

  /* Return true (1) if we were given an incomplete table */

  return y != 0 && g != 1;

}

#ifdef ASM_INFLATECODES

#  define inflate_codes(tl,td,bl,bd)  flate_codes(tl,td,bl,bd,(uchar *)slide)

   int flate_codes OF((struct huft *, struct huft *, int, int, uchar *));

#else

/* inflate (decompress) the codes in a deflated (compressed) block.

   Return an error code or zero if it all goes ok. */

static 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[] */

{

  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 ulong 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[bl];           /* precompute masks for speed */

  md = mask[bd];