lisp/gnus/mm-decode.el (mm-dissect-buffer): Guess content-type if the first token is missing in the Content-Type header

lisp/gnus/nndoc.el (nndoc-dissect-mime-parts-sub): Ditto

3 files changed, 90 insertions, 10 deletions

diff --git a/lisp/gnus/ChangeLog b/lisp/gnus/ChangeLog
index 54bc1d03a00..d3b524785f4 100644
--- a/lisp/gnus/ChangeLog
+++ b/lisp/gnus/ChangeLog
@@ -1,3 +1,10 @@
+2013-10-22  Katsumi Yamaoka  <yamaoka@jpl.org>
+
+        * mm-decode.el (mm-dissect-buffer): Guess content-type if the first
+        token is missing in the Content-Type header.
+
+        * nndoc.el (nndoc-dissect-mime-parts-sub): Ditto.
+
 2013-09-18  Glenn Morris  <rgm@gnu.org>
 
         * gnus-util.el (image-size): Declare.
diff --git a/lisp/gnus/mm-decode.el b/lisp/gnus/mm-decode.el
index 941849da183..4a9007a06ec 100644
--- a/lisp/gnus/mm-decode.el
+++ b/lisp/gnus/mm-decode.el
@@ -672,12 +672,39 @@ MIME-Version header before proceeding."
                                  description)))))
       (if (or (not ctl)
               (not (string-match "/" (car ctl))))
-          (mm-dissect-singlepart
-           (list mm-dissect-default-type)
-           (and cte (intern (downcase (mail-header-strip cte))))
-           no-strict-mime
-           (and cd (mail-header-parse-content-disposition cd))
-           description)
+          (let ((cdl (and cd (mail-header-parse-content-disposition cd))))
+            (mm-dissect-singlepart
+             ;; Guess Content-Type from the file name extention.
+             ;; Some mailer sends a part without type like this:
+             ;;  Content-Type: ; name="IMG_3156.JPG"
+             ;;  Content-Disposition: attachment; filename="IMG_3156.JPG"
+             (list (or
+                    (let ((tem
+                           (or (mail-content-type-get cdl 'filename)
+                               (and ct
+                                    (with-temp-buffer
+                                      (insert ct)
+                                      (goto-char (point-min))
+                                      (and (re-search-forward "\
+;[\t\n ]*name=\\([\"']\\|\\([^\t\n\r ]+\\)\\)" nil t)
+                                           (or (match-string 2)
+                                               (progn
+                                                 (goto-char (match-beginning 1))
+                                                 (condition-case nil
+                                                     (progn
+                                                       (forward-sexp 1)
+                                                       (buffer-substring
+                                                        (1+ (match-beginning 1))
+                                                        (1- (point))))
+                                                   (error nil))))))))))
+                      (and tem
+                           (setq tem (file-name-extension tem))
+                           (require 'mailcap)
+                           (cdr (assoc (concat "." (downcase tem))
+                                       mailcap-mime-extensions))))
+                    mm-dissect-default-type))
+             (and cte (intern (downcase (mail-header-strip cte))))
+             no-strict-mime cdl description))
         (setq type (split-string (car ctl) "/"))
         (setq subtype (cadr type)
               type (car type))
diff --git a/lisp/gnus/nndoc.el b/lisp/gnus/nndoc.el
index b17a7a6ecd8..00d9f4d4dd0 100644
--- a/lisp/gnus/nndoc.el
+++ b/lisp/gnus/nndoc.el
@@ -968,15 +968,61 @@ PARENT is the message-ID of the parent summary line, or nil for none."
     (goto-char head-begin)
     (setq content-type (message-fetch-field "Content-Type"))
     (when content-type
-      (when (string-match
-             "^ *\\([^ \t\n/;]+\\)/\\([^ \t\n/;]+\\)" content-type)
+      (with-temp-buffer
+        (insert content-type)
+        (goto-char (point-min))
+        (when (re-search-forward ";[\t\n ]*name=\\([\"']\\|\\([^\t\n\r ]+\\)\\)"
+                                 nil t)
+             (setq subject (or (match-string 2)
+                               (progn
+                                 (goto-char (match-beginning 1))
+                                 (condition-case nil
+                                     (progn
+                                       (forward-sexp 1)
+                                       (buffer-substring
+                                        (1+ (match-beginning 1)) (1- (point))))
+                                   (error nil)))))))
+      (when (or (string-match "^ *\\([^ \t\n/;]+\\)/\\([^ \t\n/;]+\\)"
+                              content-type)
+                ;; Guess Content-Type from the file name extention.
+                ;; Some mailer sends a part without type like this:
+                ;;  Content-Type: ; name="IMG_3156.JPG"
+                ;;  Content-Disposition: attachment; filename="IMG_3156.JPG"
+                (let ((tem (message-fetch-field "Content-Disposition"))
+                      (case-fold-search t)
+                      len)
+                  (when (and
+                         (setq tem
+                               (or (and tem
+                                        (mail-content-type-get
+                                         (mail-header-parse-content-disposition
+                                          tem)
+                                         'filename))
+                                   subject))
+                         (setq tem (file-name-extension tem))
+                         (require 'mailcap)
+                         (setq content-type
+                               (cdr (assoc (concat "." (downcase tem))
+                                           mailcap-mime-extensions)))
+                         (string-match "^ *\\([^ \t\n/;]+\\)/\\([^ \t\n/;]+\\)"
+                                       content-type))
+                    (save-match-data
+                      (goto-char (point-min))
+                      (when (re-search-forward "^Content-Type:\\([^;]*\\);"
+                                               nil t)
+                        (setq len (- (match-end 1) (match-beginning 1)
+                                     (length content-type))
+                              head-end (- head-end len)
+                              body-begin (- body-begin len)
+                              body-end (- body-end len))
+                        (replace-match (concat "Content-Type: " content-type
+                                               ";"))))
+                    t)))
         (setq type (downcase (match-string 1 content-type))
               subtype (downcase (match-string 2 content-type))
               message-rfc822 (and (string= type "message")
                                   (string= subtype "rfc822"))
               multipart-any (string= type "multipart")))
-      (when (string-match ";[ \t\n]*name=\\([^ \t\n;]+\\)" content-type)
-        (setq subject (match-string 1 content-type)))
       (when (string-match "boundary=\"?\\([^\"\n]*[^\" \t\n]\\)" content-type)
         (setq boundary-regexp (concat "^--"
                                       (regexp-quote