shr.el (shr-image-displayer): Protect function against non-existent image source.

2 files changed, 17 insertions, 13 deletions

diff --git a/lisp/gnus/ChangeLog b/lisp/gnus/ChangeLog
index 7d3b2d06835..b509bc39c76 100644
--- a/lisp/gnus/ChangeLog
+++ b/lisp/gnus/ChangeLog
@@ -1,5 +1,8 @@
 2010-11-17  Katsumi Yamaoka  <yamaoka@jpl.org>
 
+        * shr.el (shr-image-displayer): Protect function against non-existent
+        image source.
+
         * gnus-art.el (gnus-inhibit-images): New user option.
         (gnus-mime-display-single): Don't display image if it is non-nil.
 
diff --git a/lisp/gnus/shr.el b/lisp/gnus/shr.el
index 2dd33ecbc13..526f8121891 100644
--- a/lisp/gnus/shr.el
+++ b/lisp/gnus/shr.el
@@ -441,19 +441,20 @@ CONTENT-FUNCTION is a function to retrieve an image for a cid url that
 is an argument.  The function to be returned takes three arguments URL,
 START, and END."
   `(lambda (url start end)
-     (if (string-match "\\`cid:" url)
-         ,(when content-function
-            `(let ((image (funcall ,content-function
-                                   (substring url (match-end 0)))))
-               (when image
-                 (goto-char start)
-                 (shr-put-image image
-                                (prog1
-                                    (buffer-substring-no-properties start end)
-                                  (delete-region start end))))))
-       (url-retrieve url 'shr-image-fetched
-                     (list (current-buffer) start end)
-                     t))))
+     (when url
+       (if (string-match "\\`cid:" url)
+           ,(when content-function
+              `(let ((image (funcall ,content-function
+                                     (substring url (match-end 0)))))
+                 (when image
+                   (goto-char start)
+                   (shr-put-image image
+                                  (prog1
+                                      (buffer-substring-no-properties start end)
+                                    (delete-region start end))))))
+         (url-retrieve url 'shr-image-fetched
+                       (list (current-buffer) start end)
+                       t)))))
 
 (defun shr-heading (cont &rest types)
   (shr-ensure-paragraph)