patch-2.4.14 linux/fs/cramfs/inflate/infblock.c

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diff -u --recursive --new-file v2.4.13/linux/fs/cramfs/inflate/infblock.c linux/fs/cramfs/inflate/infblock.c
@@ -1,360 +0,0 @@
-/* infblock.c -- interpret and process block types to last block
- * Copyright (C) 1995-1998 Mark Adler
- * For conditions of distribution and use, see copyright notice in zlib.h 
- */
-
-#include "zutil.h"
-#include "infblock.h"
-#include "inftrees.h"
-#include "infcodes.h"
-#include "infutil.h"
-
-struct inflate_codes_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
-
-/* Table for deflate from PKZIP's appnote.txt. */
-local const uInt 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};
-
-/*
-   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.  Similarily, 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.
- */
-
-
-void cramfs_inflate_blocks_reset(s, z, c)
-inflate_blocks_statef *s;
-z_streamp z;
-uLongf *c;
-{
-  if (c != Z_NULL)
-    *c = s->check;
-  if (s->mode == CODES)
-    cramfs_inflate_codes_free(s->sub.decode.codes, z);
-  s->mode = TYPE;
-  s->bitk = 0;
-  s->bitb = 0;
-  s->read = s->write = s->window;
-  if (s->checkfn != Z_NULL)
-    z->adler = s->check = (*s->checkfn)(0L, (const Bytef *)Z_NULL, 0);
-}
-
-
-inflate_blocks_statef *cramfs_inflate_blocks_new(z, c, w)
-z_streamp z;
-check_func c;
-uInt w;
-{
-  inflate_blocks_statef *s;
-  static struct inflate_blocks_state working_blocks_state;
-  static inflate_huft working_hufts[MANY];
-  static unsigned char working_window[1 << MAX_WBITS];
-
-  s = &working_blocks_state;
-  s->hufts = working_hufts;
-  s->window = working_window;
-  s->end = s->window + w;
-  s->checkfn = c;
-  s->mode = TYPE;
-  cramfs_inflate_blocks_reset(s, z, Z_NULL);
-  return s;
-}
-
-
-int cramfs_inflate_blocks(s, z, r)
-inflate_blocks_statef *s;
-z_streamp z;
-int r;
-{
-  uInt t;               /* temporary storage */
-  uLong b;              /* bit buffer */
-  uInt k;               /* bits in bit buffer */
-  Bytef *p;             /* input data pointer */
-  uInt n;               /* bytes available there */
-  Bytef *q;             /* output window write pointer */
-  uInt m;               /* bytes to end of window or read pointer */
-
-  /* copy input/output information to locals (UPDATE macro restores) */
-  LOAD
-
-  /* process input based on current state */
-  while (1) switch (s->mode)
-  {
-    case TYPE:
-      NEEDBITS(3)
-      t = (uInt)b & 7;
-      s->last = t & 1;
-      switch (t >> 1)
-      {
-        case 0:                         /* stored */
-          DUMPBITS(3)
-          t = k & 7;                    /* go to byte boundary */
-          DUMPBITS(t)
-          s->mode = LENS;               /* get length of stored block */
-          break;
-        case 1:                         /* fixed */
-          {
-            uInt bl, bd;
-            inflate_huft *tl, *td;
-
-            cramfs_inflate_trees_fixed(&bl, &bd, &tl, &td, z);
-            s->sub.decode.codes = cramfs_inflate_codes_new(bl, bd, tl, td, z);
-            if (s->sub.decode.codes == Z_NULL)
-            {
-              r = Z_MEM_ERROR;
-              LEAVE
-            }
-          }
-          DUMPBITS(3)
-          s->mode = CODES;
-          break;
-        case 2:                         /* dynamic */
-          DUMPBITS(3)
-          s->mode = TABLE;
-          break;
-        case 3:                         /* illegal */
-          DUMPBITS(3)
-          s->mode = BAD;
-          z->msg = (char*)"invalid block type";
-          r = Z_DATA_ERROR;
-          LEAVE
-      }
-      break;
-    case LENS:
-      NEEDBITS(32)
-      if ((((~b) >> 16) & 0xffff) != (b & 0xffff))
-      {
-        s->mode = BAD;
-        z->msg = (char*)"invalid stored block lengths";
-        r = Z_DATA_ERROR;
-        LEAVE
-      }
-      s->sub.left = (uInt)b & 0xffff;
-      b = k = 0;                      /* dump bits */
-      s->mode = s->sub.left ? STORED : (s->last ? DRY : TYPE);
-      break;
-    case STORED:
-      if (n == 0)
-        LEAVE
-      NEEDOUT
-      t = s->sub.left;
-      if (t > n) t = n;
-      if (t > m) t = m;
-      memcpy(q, p, t);
-      p += t;  n -= t;
-      q += t;  m -= t;
-      if ((s->sub.left -= t) != 0)
-        break;
-      s->mode = s->last ? DRY : TYPE;
-      break;
-    case TABLE:
-      NEEDBITS(14)
-      s->sub.trees.table = t = (uInt)b & 0x3fff;
-#ifndef PKZIP_BUG_WORKAROUND
-      if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29)
-      {
-        s->mode = BAD;
-        z->msg = (char*)"too many length or distance symbols";
-        r = Z_DATA_ERROR;
-        LEAVE
-      }
-#endif
-      {
-      	static unsigned int working_blens [258 + 0x1f + 0x1f];
-      	s->sub.trees.blens = working_blens;
-      }
-      DUMPBITS(14)
-      s->sub.trees.index = 0;
-      s->mode = BTREE;
-    case BTREE:
-      while (s->sub.trees.index < 4 + (s->sub.trees.table >> 10))
-      {
-        NEEDBITS(3)
-        s->sub.trees.blens[border[s->sub.trees.index++]] = (uInt)b & 7;
-        DUMPBITS(3)
-      }
-      while (s->sub.trees.index < 19)
-        s->sub.trees.blens[border[s->sub.trees.index++]] = 0;
-      s->sub.trees.bb = 7;
-      t = cramfs_inflate_trees_bits(s->sub.trees.blens, &s->sub.trees.bb,
-                             &s->sub.trees.tb, s->hufts, z);
-      if (t != Z_OK)
-      {
-        r = t;
-        if (r == Z_DATA_ERROR)
-          s->mode = BAD;
-        LEAVE
-      }
-      s->sub.trees.index = 0;
-      s->mode = DTREE;
-    case DTREE:
-      while (t = s->sub.trees.table,
-             s->sub.trees.index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f))
-      {
-        inflate_huft *h;
-        uInt i, j, c;
-
-        t = s->sub.trees.bb;
-        NEEDBITS(t)
-        h = s->sub.trees.tb + ((uInt)b & cramfs_inflate_mask[t]);
-        t = h->bits;
-        c = h->base;
-        if (c < 16)
-        {
-          DUMPBITS(t)
-          s->sub.trees.blens[s->sub.trees.index++] = c;
-        }
-        else /* c == 16..18 */
-        {
-          i = c == 18 ? 7 : c - 14;
-          j = c == 18 ? 11 : 3;
-          NEEDBITS(t + i)
-          DUMPBITS(t)
-          j += (uInt)b & cramfs_inflate_mask[i];
-          DUMPBITS(i)
-          i = s->sub.trees.index;
-          t = s->sub.trees.table;
-          if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) ||
-              (c == 16 && i < 1))
-          {
-            s->mode = BAD;
-            z->msg = (char*)"invalid bit length repeat";
-            r = Z_DATA_ERROR;
-            LEAVE
-          }
-          c = c == 16 ? s->sub.trees.blens[i - 1] : 0;
-          do {
-            s->sub.trees.blens[i++] = c;
-          } while (--j);
-          s->sub.trees.index = i;
-        }
-      }
-      s->sub.trees.tb = Z_NULL;
-      {
-        uInt bl, bd;
-        inflate_huft *tl, *td;
-        inflate_codes_statef *c;
-
-        bl = 9;         /* must be <= 9 for lookahead assumptions */
-        bd = 6;         /* must be <= 9 for lookahead assumptions */
-        t = s->sub.trees.table;
-        t = cramfs_inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f),
-                                  s->sub.trees.blens, &bl, &bd, &tl, &td,
-                                  s->hufts, z);
-        if (t != Z_OK)
-        {
-          if (t == (uInt)Z_DATA_ERROR)
-            s->mode = BAD;
-          r = t;
-          LEAVE
-        }
-        if ((c = cramfs_inflate_codes_new(bl, bd, tl, td, z)) == Z_NULL)
-        {
-          r = Z_MEM_ERROR;
-          LEAVE
-        }
-        s->sub.decode.codes = c;
-      }
-      s->mode = CODES;
-    case CODES:
-      UPDATE
-      if ((r = cramfs_inflate_codes(s, z, r)) != Z_STREAM_END)
-        return cramfs_inflate_flush(s, z, r);
-      r = Z_OK;
-      cramfs_inflate_codes_free(s->sub.decode.codes, z);
-      LOAD
-      if (!s->last)
-      {
-        s->mode = TYPE;
-        break;
-      }
-      s->mode = DRY;
-    case DRY:
-      FLUSH
-      if (s->read != s->write)
-        LEAVE
-      s->mode = DONE;
-    case DONE:
-      r = Z_STREAM_END;
-      LEAVE
-    case BAD:
-      r = Z_DATA_ERROR;
-      LEAVE
-    default:
-      r = Z_STREAM_ERROR;
-      LEAVE
-  }
-}
-
-
-int cramfs_inflate_blocks_free(s, z)
-inflate_blocks_statef *s;
-z_streamp z;
-{
-  cramfs_inflate_blocks_reset(s, z, Z_NULL);
-  return Z_OK;
-}
-
-
-void cramfs_inflate_set_dictionary(s, d, n)
-inflate_blocks_statef *s;
-const Bytef *d;
-uInt  n;
-{
-  memcpy(s->window, d, n);
-  s->read = s->write = s->window + n;
-}
-
-
-/* Returns true if inflate is currently at the end of a block generated
- * by Z_SYNC_FLUSH or Z_FULL_FLUSH. 
- * IN assertion: s != Z_NULL
- */
-int inflate_blocks_sync_point(s)
-inflate_blocks_statef *s;
-{
-  return s->mode == LENS;
-}

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