master ef14acf: Make nnml handle invalid non-ASCII headers more consistently

[Lars Ingebrigtsen]

branch: master
commit ef14acfb68bb5b0ce42221e9681b93562f8085eb
Author: Lars Ingebrigtsen <larsi@gnus.org>
Commit: Lars Ingebrigtsen <larsi@gnus.org>

    Make nnml handle invalid non-ASCII headers more consistently
    
    * lisp/gnus/nnml.el (nnml--encode-headers): New function to
    RFC2047-encode invalid Subject/From headers (bug#45925).  This
    will make them be displayed more consistently in the Summary
    buffer (but still "wrong" sometimes, since there's not that much
    we can guess at at this stage, charset wise).
    (nnml-parse-head): Use it.
---
 lisp/gnus/nnml.el | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/lisp/gnus/nnml.el b/lisp/gnus/nnml.el
index ebececa..3cdfc74 100644
--- a/lisp/gnus/nnml.el
+++ b/lisp/gnus/nnml.el
@@ -769,8 +769,24 @@ article number.  This function is called narrowed to an 
article."
       (let ((headers (nnheader-parse-head t)))
        (setf (mail-header-chars  headers) chars)
        (setf (mail-header-number headers) number)
+       ;; If there's non-ASCII raw characters in the data,
+       ;; RFC2047-encode them to avoid having arbitrary data in the
+       ;; .overview file.
+       (nnml--encode-headers headers)
        headers))))
 
+(defun nnml--encode-headers (headers)
+  (let ((subject (mail-header-subject headers))
+       (rfc2047-encoding-type 'mime))
+    (unless (string-match "\\`[[:ascii:]]*\\'" subject)
+      (setf (mail-header-subject headers)
+           (mail-encode-encoded-word-string subject t))))
+  (let ((from (mail-header-from headers))
+       (rfc2047-encoding-type 'address-mime))
+    (unless (string-match "\\`[[:ascii:]]*\\'" from)
+      (setf (mail-header-from headers)
+           (rfc2047-encode-string from t)))))
+
 (defun nnml-get-nov-buffer (group &optional incrementalp)
   (let ((buffer (gnus-get-buffer-create
                  (format " *nnml %soverview %s*"