refactor(3p/lisp/mime4cl): use qbase64 for decoding FILE-PORTIONs

Porting over the rest of the decoding (RFC2047) and especially encoding
over to qbase64 is still pending, as it is a little trickier.

Change-Id: Id4740eb074a387aeea2cb94b781e204248530799
Reviewed-on: https://cl.tvl.fyi/c/depot/+/8582
Autosubmit: sterni <sternenseemann@systemli.org>
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI

third_party/lisp/mime4cl/default.nix

@@ -9,6 +9,7 @@ depot.nix.buildLisp.library {
     depot.third_party.lisp.flexi-streams
     depot.third_party.lisp.npg
     depot.third_party.lisp.trivial-gray-streams
+    depot.third_party.lisp.qbase64
   ];
 
   srcs = [

third_party/lisp/mime4cl/streams.lisp

@@ -45,7 +45,6 @@
   '(unsigned-byte 8))
 
 (defclass quoted-printable-decoder-stream (coder-input-stream-mixin quoted-printable-decoder) ())
-(defclass base64-decoder-stream (coder-input-stream-mixin base64-decoder) ())
 (defclass 8bit-decoder-stream (coder-input-stream-mixin 8bit-decoder) ())
 
 (defclass quoted-printable-encoder-stream (coder-output-stream-mixin quoted-printable-encoder) ())
@@ -262,7 +261,7 @@ be modified to match the :POSITION argument."
           (make-instance
            (ccase encoding
              (:quoted-printable 'quoted-printable-decoder-stream)
-             (:base64 'base64-decoder-stream))
+             (:base64 'qbase64:decode-stream))
            :underlying-stream portion-stream)
           portion-stream))))
 

users/sterni/mblog/config.lisp

@@ -28,4 +28,4 @@
                     (setf ,name (funcall ,parser ,val-var-sym))))))))
 
 (define-configuration-variables
-  *general-buffer-size* 4096 #'parse-integer)
+  *general-buffer-size* (min 4096 qbase64:+max-bytes-length+) #'parse-integer)