fix zip/gzip bug

Closes PR 12605 original commit: f9247ff3a5a772c8a314a4c9444e449c5b113053
2012-02-27 08:34:26 -05:00 · 2012-02-27 08:34:26 -05:00 · a2ce5dbafd
commit a2ce5dbafd
parent b2faf6534a
1 changed files with 3 additions and 2 deletions
--- a/collects/mzlib/deflate.rkt
+++ b/collects/mzlib/deflate.rkt
@ -469,7 +469,8 @@
        (longest_match-loop)))
    (define (*++scan)
      (set! scanpos (add1 scanpos))
-      (bytes-ref window-vec scanpos))
+      (and (scanpos . < . window_size) ; the original C code can read past the end of the buffer
+           (bytes-ref window-vec scanpos)))
    (define (*++match)
      (set! matchpos (add1 matchpos))
      (bytes-ref window-vec matchpos))