master c05f102: Tweat how MML specifies the encoding of binary data

[Lars Ingebrigtsen]

branch: master
commit c05f1020cecb4ef7d516e6575c86bf009c2e6f00
Author: Lars Ingebrigtsen <larsi@gnus.org>
Commit: Lars Ingebrigtsen <larsi@gnus.org>

    Tweat how MML specifies the encoding of binary data
    
    * lisp/gnus/mml.el (mml-parse-1): Use `data-encoding' to be
    slightly less confusing than `content-transfer-encoding'.
    
    * doc/misc/emacs-mime.texi (MML Definition): Document it.
    
    * lisp/gnus/message.el (message-insert-screenshot): Adjust usage.
---
 doc/misc/emacs-mime.texi | 13 +++++++++++--
 lisp/gnus/message.el     |  2 +-
 lisp/gnus/mml.el         |  4 ++--
 3 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/doc/misc/emacs-mime.texi b/doc/misc/emacs-mime.texi
index 974cc10..9180b4e 100644
--- a/doc/misc/emacs-mime.texi
+++ b/doc/misc/emacs-mime.texi
@@ -693,8 +693,17 @@ Valid values are @samp{inline} and @samp{attachment}
 
 @item encoding
 Valid values are @samp{7bit}, @samp{8bit}, @samp{quoted-printable} and
-@samp{base64} (@code{Content-Transfer-Encoding}). @xref{Charset
-Translation}.
+@samp{base64}.  @xref{Charset
+Translation}.  This parameter says what
+@code{Content-Transfer-Encoding} to use when sending the part, and is
+normally computed automatically.
+
+@item data-encoding
+This parameter says what encoding has been used on the data, and the
+data will be decoded before use.  Valid values are
+@samp{quoted-printable} and @samp{base64}.  This is useful when you
+have a part with binary data (for instance an image) inserted directly
+into the Message buffer inside the @samp{"<#part>...<#/part>"} tags.
 
 @item description
 A description of the part (@code{Content-Description}).
diff --git a/lisp/gnus/message.el b/lisp/gnus/message.el
index 6c0f9b5..819f3e4 100644
--- a/lisp/gnus/message.el
+++ b/lisp/gnus/message.el
@@ -8709,7 +8709,7 @@ used to take the screenshot."
                   :max-width (truncate (* (frame-pixel-width) 0.8))
                   :max-height (truncate (* (frame-pixel-height) 0.8))
                   :scale 1)
-     (format "<#part type=\"image/png\" disposition=inline 
content-transfer-encoding=base64 raw=t>\n%s\n<#/part>"
+     (format "<#part type=\"image/png\" disposition=inline 
data-encoding=base64 raw=t>\n%s\n<#/part>"
             ;; Get a base64 version of the image -- this avoids later
             ;; complications if we're auto-saving the buffer and
             ;; restoring from a file.
diff --git a/lisp/gnus/mml.el b/lisp/gnus/mml.el
index 1d348f3..ef8aa6a 100644
--- a/lisp/gnus/mml.el
+++ b/lisp/gnus/mml.el
@@ -298,12 +298,12 @@ part.  This is for the internal use, you should never 
modify the value.")
        ;; We have a part that already has a transfer encoding.  Undo
        ;; that so that we don't double-encode later.
        (when (and raw
-                  (cdr (assq 'content-transfer-encoding tag)))
+                  (cdr (assq 'data-encoding tag)))
          (with-temp-buffer
            (set-buffer-multibyte nil)
            (insert contents)
            (mm-decode-content-transfer-encoding
-            (intern (cdr (assq 'content-transfer-encoding tag)))
+            (intern (cdr (assq 'data-encoding tag)))
             (cdr (assq 'type tag)))
            (setq contents (buffer-string))))
        (when (and (not raw) (memq nil charsets))