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

• Lines: 162
• Date: Wed Dec 31 16:00:00 1969
• Orig file: v2.4.13/linux/fs/cramfs/inflate/inffast.c
• Orig date: Wed Apr 12 09:47:29 2000

diff -u --recursive --new-file v2.4.13/linux/fs/cramfs/inflate/inffast.c linux/fs/cramfs/inflate/inffast.c
@@ -1,161 +0,0 @@
-/* inffast.c -- process literals and length/distance pairs fast
- * 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 "infblock.h"
-#include "infcodes.h"
-#include "infutil.h"
-#include "inffast.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
-
-/* macros for bit input with no checking and for returning unused bytes */
-#define GRABBITS(j) {while(k<(j)){b|=((uLong)NEXTBYTE)<<k;k+=8;}}
-#define UNGRAB {c=z->avail_in-n;c=(k>>3)<c?k>>3:c;n+=c;p-=c;k-=c<<3;}
-
-/* Called with number of bytes left to write in window at least 258
-   (the maximum string length) and number of input bytes available
-   at least ten.  The ten bytes are six bytes for the longest length/
-   distance pair plus four bytes for overloading the bit buffer. */
-
-int cramfs_inflate_fast(bl, bd, tl, td, s, z)
-uInt bl, bd;
-inflate_huft *tl;
-inflate_huft *td; /* need separate declaration for Borland C++ */
-inflate_blocks_statef *s;
-z_streamp z;
-{
-  inflate_huft *t;      /* temporary pointer */
-  uInt e;               /* extra bits or operation */
-  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 */
-  uInt ml;              /* mask for literal/length tree */
-  uInt md;              /* mask for distance tree */
-  uInt c;               /* bytes to copy */
-  uInt d;               /* distance back to copy from */
-  Bytef *r;             /* copy source pointer */
-
-  /* load input, output, bit values */
-  LOAD
-
-  /* initialize masks */
-  ml = cramfs_inflate_mask[bl];
-  md = cramfs_inflate_mask[bd];
-
-  /* do until not enough input or output space for fast loop */
-  do {                          /* assume called with m >= 258 && n >= 10 */
-    /* get literal/length code */
-    GRABBITS(20)                /* max bits for literal/length code */
-    if ((e = (t = tl + ((uInt)b & ml))->exop) == 0)
-    {
-      DUMPBITS(t->bits)
-      *q++ = (Byte)t->base;
-      m--;
-      continue;
-    }
-    do {
-      DUMPBITS(t->bits)
-      if (e & 16)
-      {
-        /* get extra bits for length */
-        e &= 15;
-        c = t->base + ((uInt)b & cramfs_inflate_mask[e]);
-        DUMPBITS(e)
-
-        /* decode distance base of block to copy */
-        GRABBITS(15);           /* max bits for distance code */
-        e = (t = td + ((uInt)b & md))->exop;
-        do {
-          DUMPBITS(t->bits)
-          if (e & 16)
-          {
-            /* get extra bits to add to distance base */
-            e &= 15;
-            GRABBITS(e)         /* get extra bits (up to 13) */
-            d = t->base + ((uInt)b & cramfs_inflate_mask[e]);
-            DUMPBITS(e)
-
-            /* do the copy */
-            m -= c;
-            if ((uInt)(q - s->window) >= d)     /* offset before dest */
-            {                                   /*  just copy */
-              r = q - d;
-              *q++ = *r++;  c--;        /* minimum count is three, */
-              *q++ = *r++;  c--;        /*  so unroll loop a little */
-            }
-            else                        /* else offset after destination */
-            {
-              e = d - (uInt)(q - s->window); /* bytes from offset to end */
-              r = s->end - e;           /* pointer to offset */
-              if (c > e)                /* if source crosses, */
-              {
-                c -= e;                 /* copy to end of window */
-                do {
-                  *q++ = *r++;
-                } while (--e);
-                r = s->window;          /* copy rest from start of window */
-              }
-            }
-            do {                        /* copy all or what's left */
-              *q++ = *r++;
-            } while (--c);
-            break;
-          }
-          else if ((e & 64) == 0)
-          {
-            t += t->base;
-            e = (t += ((uInt)b & cramfs_inflate_mask[e]))->exop;
-          }
-          else
-          {
-            z->msg = (char*)"invalid distance code";
-            UNGRAB
-            UPDATE
-            return Z_DATA_ERROR;
-          }
-        } while (1);
-        break;
-      }
-      if ((e & 64) == 0)
-      {
-        t += t->base;
-        if ((e = (t += ((uInt)b & cramfs_inflate_mask[e]))->exop) == 0)
-        {
-          DUMPBITS(t->bits)
-          *q++ = (Byte)t->base;
-          m--;
-          break;
-        }
-      }
-      else if (e & 32)
-      {
-        UNGRAB
-        UPDATE
-        return Z_STREAM_END;
-      }
-      else
-      {
-        z->msg = (char*)"invalid literal/length code";
-        UNGRAB
-        UPDATE
-        return Z_DATA_ERROR;
-      }
-    } while (1);
-  } while (m >= 258 && n >= 10);
-
-  /* not enough input or output--restore pointers and return */
-  UNGRAB
-  UPDATE
-  return Z_OK;
-}