Handle unexpected eof after =.

net-lib/net/qp.rkt

@@ -77,6 +77,9 @@
                   (loop (read-byte in))
                   ;; Not a LF? Well, ok.
                   (loop next-next)))]
+             [(eof-object? next)
+              (warning "Illegal qp sequence: `='")
+              (display "=" out)]
              [(hex-digit? next)
               (let ([next-next (read-byte in)])
                 (cond [(eof-object? next-next)

net-test/tests/net/encoders.rkt

@@ -79,7 +79,8 @@
    do (check-same-all base64-encode-stream
                       base64-decode-stream
                       #rx#"^[0-9a-zA-Z+=/]*$"
-                      72)))
+                      72))
+  (test (qp-decode #"=20=") #" ="))
 
 #|
 Use this to compare base64 encode/decode against the unix utilities