X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/c801d85f158c4cba50b588807daabdcbd0ed3853..d440a0e764687c595254539539b0cd6e3b075590:/src/zlib/inffast.c

diff --git a/src/zlib/inffast.c b/src/zlib/inffast.c
index 61a78ee933..0e41957fef 100644
--- a/src/zlib/inffast.c
+++ b/src/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 
+ * Copyright (C) 1995-2002 Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
  */
 
 #include "zutil.h"
@@ -25,12 +25,16 @@ struct inflate_codes_state {int dummy;}; /* for buggy compilers */
    at least ten.  The ten bytes are six bytes for the longest length/
    distance pair plus four bytes for overloading the bit buffer. */
 
+#if defined(__VISAGECPP__) /* Visualage can't handle this antiquated interface */
+int inflate_fast(uInt bl, uInt bd, inflate_huft* tl, inflate_huft* td, inflate_blocks_statef* s, z_streamp z)
+#else
 int 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;
+#endif
 {
   inflate_huft *t;      /* temporary pointer */
   uInt e;               /* extra bits or operation */
@@ -93,28 +97,41 @@ 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 */
+            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++;
                 } 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 */
+            else                                /* normal copy */
+            {
+              *q++ = *r++;  c--;
+              *q++ = *r++;  c--;
+              do {
               *q++ = *r++;
             } while (--c);
+            }
             break;
           }
           else if ((e & 64) == 0)