+(defun rmail-epa-decrypt-1 (mime)
+ "Decrypt a single GnuPG encrypted text in a message.
+The starting string of the encrypted text should have just been regexp-matched.
+Argument MIME is non-nil if this is a mime message."
+ (let* ((armor-start (match-beginning 0))
+ (armor-prefix (buffer-substring
+ (line-beginning-position)
+ armor-start))
+ (armor-end-regexp)
+ armor-end after-end
+ unquote)
+ (if (string-match "<pre>\\'" armor-prefix)
+ (setq armor-prefix ""))
+
+ (setq armor-end-regexp
+ (concat "^"
+ armor-prefix
+ "-----END PGP MESSAGE-----$"))
+ (setq armor-end (re-search-forward armor-end-regexp
+ nil t))
+
+ (unless armor-end
+ (error "Encryption armor beginning has no matching end"))
+ (goto-char armor-start)
+
+ ;; Because epa--find-coding-system-for-mime-charset not autoloaded.
+ (require 'epa)
+
+ ;; Advance over this armor.
+ (goto-char armor-end)
+ (setq after-end (- (point-max) armor-end))
+
+ (when mime
+ (save-excursion
+ (goto-char armor-start)
+ (re-search-backward "^--" nil t)
+ (save-restriction
+ (narrow-to-region (point) armor-start)
+
+ ;; Use the charset specified in the armor.
+ (unless coding-system-for-read
+ (if (re-search-forward "^[ \t]*Charset[ \t\n]*:[ \t\n]*\\(.*\\)" nil t)
+ (setq coding-system-for-read
+ (epa--find-coding-system-for-mime-charset
+ (intern (downcase (match-string 1)))))))
+
+ (goto-char (point-min))
+ (if (re-search-forward "^[ \t]*Content-transfer-encoding[ \t\n]*:[ \t\n]*quoted-printable[ \t]*$" nil t)
+ (setq unquote t)))))
+
+ (when unquote
+ (let ((inhibit-read-only t))
+ (mail-unquote-printable-region armor-start
+ (- (point-max) after-end))))
+
+ ;; Decrypt it, maybe in place, maybe making new buffer.
+ (epa-decrypt-region
+ armor-start (- (point-max) after-end)
+ ;; Call back this function to prepare the output.
+ (lambda ()
+ (let ((inhibit-read-only t))
+ (delete-region armor-start (- (point-max) after-end))
+ (goto-char armor-start)
+ (current-buffer))))
+
+ (list armor-start (- (point-max) after-end) mime
+ armor-end-regexp)))
+