Display images from gpg signatures

* epg.el (epg-signature-to-string): Use new functions
epg-key-image, epg-key-image-to-string to find and display image
from key.

2 files changed, 32 insertions, 2 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 2181a6dde7e..73379a93027 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,9 @@
+2012-12-25  Adam Sjøgren  <asjo@koldfront.dk>
+
+        * epg.el (epg-signature-to-string): Use new functions
+        epg-key-image, epg-key-image-to-string to find and display image
+        from key.
+
 2012-12-24  Constantin Kulikov <zxnotdead@gmail.com>  (tiny change)
 
         * startup.el (initial-buffer-choice): Allow function as value
diff --git a/lisp/epg.el b/lisp/epg.el
index 833a68d6e7e..b79c5df4165 100644
--- a/lisp/epg.el
+++ b/lisp/epg.el
@@ -967,11 +967,34 @@ This function is for internal use only."
         (setcdr entry value)
       (epg-context-set-result context (cons (cons name value) result)))))
 
+(defun epg-key-image (key-id)
+  "Return the image of a key, if any"
+  (let ((filename
+         (replace-regexp-in-string
+          "\n" ""
+          (shell-command-to-string
+           (concat "/usr/bin/gpg --photo-viewer 'echo %I >&2' --list-keys "
+                   key-id " > /dev/null")))))
+    (when (and (not (string-equal filename ""))
+               (file-exists-p filename))
+      (create-image filename))))
+
+(defun epg-key-image-to-string (key-id)
+  "Return a string with the image of a key, if any"
+  (let* ((result "")
+         (key-image (epg-key-image key-id)))
+    (when key-image
+      (setq result "  ")
+      (put-text-property 1 2 'display key-image result))
+    result))
+
 (defun epg-signature-to-string (signature)
   "Convert SIGNATURE to a human readable string."
   (let* ((user-id (cdr (assoc (epg-signature-key-id signature)
                               epg-user-id-alist)))
-         (pubkey-algorithm (epg-signature-pubkey-algorithm signature)))
+         (pubkey-algorithm (epg-signature-pubkey-algorithm signature))
+         (key-id (epg-signature-key-id signature))
+         (key-image (epg-key-image-to-string key-id)))
     (concat
      (cond ((eq (epg-signature-status signature) 'good)
             "Good signature from ")
@@ -985,7 +1008,8 @@ This function is for internal use only."
             "Signature made by revoked key ")
            ((eq (epg-signature-status signature) 'no-pubkey)
             "No public key for "))
-     (epg-signature-key-id signature)
+     key-id
+     key-image
      (if user-id
          (concat " "
                  (if (stringp user-id)