/* inffast.c -- process literals and length/distance pairs fast
- * Copyright (C) 1995 Mark Adler
+ * Copyright (C) 1995-2002 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 base more.Base
-#define next more.Next
#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 {n+=(c=k>>3);p-=c;k&=7;}
+#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
int inflate_fast(bl, bd, tl, td, s, z)
uInt bl, bd;
-inflate_huft *tl, *td;
-struct inflate_blocks_state *s;
-z_stream *z;
+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 */
- Byte *p; /* input data pointer */
+ Bytef *p; /* input data pointer */
uInt n; /* bytes available there */
- Byte *q; /* output window write pointer */
+ 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 */
- Byte *r; /* copy source pointer */
+ Bytef *r; /* copy source pointer */
/* load input, output, bit values */
LOAD
/* 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 */
+ r = q - d;
+ if (r < s->window) /* wrap if needed */
{
- e = d - (q - s->window); /* bytes from offset to end */
- r = s->end - e; /* pointer to offset */
- if (c > e) /* if source crosses, */
+ do {
+ r += s->end - s->window; /* force pointer in window */
+ } while (r < s->window); /* covers invalid distances */
+ e = s->end - r;
+ if (c > e)
{
- c -= e; /* copy to end of window */
+ c -= e; /* wrapped copy */
do {
- *q++ = *r++;
+ *q++ = *r++;
} while (--e);
- r = s->window; /* copy rest from start of window */
+ r = s->window;
+ do {
+ *q++ = *r++;
+ } while (--c);
+ }
+ else /* normal copy */
+ {
+ *q++ = *r++; c--;
+ *q++ = *r++; c--;
+ do {
+ *q++ = *r++;
+ } while (--c);
}
}
- do { /* copy all or what's left */
- *q++ = *r++;
- } while (--c);
+ else /* normal copy */
+ {
+ *q++ = *r++; c--;
+ *q++ = *r++; c--;
+ do {
+ *q++ = *r++;
+ } while (--c);
+ }
break;
}
else if ((e & 64) == 0)
- e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop;
+ {
+ t += t->base;
+ e = (t += ((uInt)b & inflate_mask[e]))->exop;
+ }
else
{
- z->msg = "invalid distance code";
+ z->msg = (char*)"invalid distance code";
UNGRAB
UPDATE
return Z_DATA_ERROR;
}
if ((e & 64) == 0)
{
- if ((e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop) == 0)
+ t += t->base;
+ if ((e = (t += ((uInt)b & inflate_mask[e]))->exop) == 0)
{
DUMPBITS(t->bits)
Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
}
else
{
- z->msg = "invalid literal/length code";
+ z->msg = (char*)"invalid literal/length code";
UNGRAB
UPDATE
return Z_DATA_ERROR;