epg: don't start pinentry if it is useless

* lisp/epg.el (epg--start): Don't start pinentry server if the
session is non-interactive or pinentry-mode is set.

1 files changed, 6 insertions, 2 deletions

diff --git a/lisp/epg.el b/lisp/epg.el
index f4058ed35a4..d37db110be6 100644
--- a/lisp/epg.el
+++ b/lisp/epg.el
@@ -604,9 +604,13 @@ callback data (if any)."
       (setq process-environment
             (cons (concat "GPG_TTY=" terminal-name)
                   (cons "TERM=xterm" process-environment))))
-    ;; Start the Emacs Pinentry server if allow-emacs-pinentry is set
-    ;; in ~/.gnupg/gpg-agent.conf.
+    ;; Automatically start the Emacs Pinentry server if appropriate.
     (when (and (fboundp 'pinentry-start)
+               ;; Emacs Pinentry is useless if Emacs has no interactive session.
+               (not noninteractive)
+               ;; Prefer pinentry-mode over Emacs Pinentry.
+               (null (epg-context-pinentry-mode context))
+               ;; Check if the allow-emacs-pinentry option is set.
                (executable-find epg-gpgconf-program)
                (with-temp-buffer
                  (when (= (call-process epg-gpgconf-program nil t nil