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-rw-r--r--src/utilfuns/zlib/inffast.c47
1 files changed, 30 insertions, 17 deletions
diff --git a/src/utilfuns/zlib/inffast.c b/src/utilfuns/zlib/inffast.c
index 61a78ee..aa7f1d4 100644
--- a/src/utilfuns/zlib/inffast.c
+++ b/src/utilfuns/zlib/inffast.c
@@ -1,5 +1,5 @@
/* inffast.c -- process literals and length/distance pairs fast
- * Copyright (C) 1995-1998 Mark Adler
+ * Copyright (C) 1995-2002 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
@@ -93,28 +93,41 @@ z_streamp z;
/* 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 - (uInt)(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);
+ }
+ }
+ 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);
break;
}
else if ((e & 64) == 0)