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-rw-r--r--main/zlib/inffast.c246
1 files changed, 117 insertions, 129 deletions
diff --git a/main/zlib/inffast.c b/main/zlib/inffast.c
index 61a78ee..b49f4e2 100644
--- a/main/zlib/inffast.c
+++ b/main/zlib/inffast.c
@@ -1,6 +1,6 @@
/* 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
+ * For conditions of distribution and use, see copyright notice in zlib.h
*/
#include "zutil.h"
@@ -10,7 +10,9 @@
#include "infutil.h"
#include "inffast.h"
-struct inflate_codes_state {int dummy;}; /* for buggy compilers */
+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
@@ -32,139 +34,125 @@ 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 */
+ 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
+ /* load input, output, bit values */
+ LOAD
- /* initialize masks */
- ml = inflate_mask[bl];
- md = inflate_mask[bd];
+ /* initialize masks */
+ ml = inflate_mask[bl];
+ md = 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)
- Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
- "inflate: * literal '%c'\n" :
- "inflate: * literal 0x%02x\n", t->base));
- *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 & inflate_mask[e]);
- DUMPBITS(e)
- Tracevv((stderr, "inflate: * length %u\n", c));
-
- /* decode distance base of block to copy */
- GRABBITS(15); /* max bits for distance code */
- e = (t = td + ((uInt)b & md))->exop;
+ /* 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)
+ Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
+ "inflate: * literal '%c'\n" :
+ "inflate: * literal 0x%02x\n", t->base));
+ *q++ = (Byte)t->base;
+ m--;
+ continue;
+ }
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 & inflate_mask[e]);
- DUMPBITS(e)
- Tracevv((stderr, "inflate: * distance %u\n", d));
+ DUMPBITS(t->bits)
+ if(e & 16) {
+ /* get extra bits for length */
+ e &= 15;
+ c = t->base + ((uInt)b & inflate_mask[e]);
+ DUMPBITS(e)
+ Tracevv((stderr, "inflate: * length %u\n", c));
- /* 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 */
+ /* decode distance base of block to copy */
+ GRABBITS(15); /* max bits for distance code */
+ e = (t = td + ((uInt)b & md))->exop;
do {
- *q++ = *r++;
- } while (--e);
- r = s->window; /* copy rest from start of window */
- }
+ 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 & inflate_mask[e]);
+ DUMPBITS(e)
+ Tracevv((stderr, "inflate: * distance %u\n", d));
+
+ /* 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 & inflate_mask[e]))->exop;
+ } else {
+ z->msg = (char *)"invalid distance code";
+ UNGRAB
+ UPDATE
+ return Z_DATA_ERROR;
+ }
+ } while(1);
+ break;
}
- do { /* copy all or what's left */
- *q++ = *r++;
- } while (--c);
- break;
- }
- else if ((e & 64) == 0)
- {
- t += t->base;
- e = (t += ((uInt)b & 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 & inflate_mask[e]))->exop) == 0)
- {
- DUMPBITS(t->bits)
- Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
- "inflate: * literal '%c'\n" :
- "inflate: * literal 0x%02x\n", t->base));
- *q++ = (Byte)t->base;
- m--;
- break;
- }
- }
- else if (e & 32)
- {
- Tracevv((stderr, "inflate: * end of block\n"));
- 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);
+ if((e & 64) == 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 ?
+ "inflate: * literal '%c'\n" :
+ "inflate: * literal 0x%02x\n", t->base));
+ *q++ = (Byte)t->base;
+ m--;
+ break;
+ }
+ } else if(e & 32) {
+ Tracevv((stderr, "inflate: * end of block\n"));
+ 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;
+ /* not enough input or output--restore pointers and return */
+ UNGRAB
+ UPDATE
+ return Z_OK;
}
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