proto-stream.el (open-protocol-stream): Protect against the low-level transport functions returning nil.

gnus-sum.el (gnus-summary-next-article): Remove hack to reselect group window, because it does the wrong thing when a separate frame displays the group buffer.
gnus-int.el (gnus-request-accept-article): Don't try to update marks and stuff if the backend didn't return the article number.  This fixes an Exchange-related nnimap bug.
mm-decode.el (mm-preferred-alternative-precedence): Discourage showing empty parts.
nnimap.el (nnimap-convert-partial-article): Protect against zero-length body parts.

6 files changed, 49 insertions, 23 deletions

diff --git a/lisp/gnus/ChangeLog b/lisp/gnus/ChangeLog
index abbddcc49cc..c0c6533d531 100644
--- a/lisp/gnus/ChangeLog
+++ b/lisp/gnus/ChangeLog
@@ -1,3 +1,22 @@
+2011-01-11  Lars Magne Ingebrigtsen  <larsi@gnus.org>
+
+        * nnimap.el (nnimap-convert-partial-article): Protect against
+        zero-length body parts.
+
+        * mm-decode.el (mm-preferred-alternative-precedence): Discourage
+        showing empty parts.
+
+        * gnus-int.el (gnus-request-accept-article): Don't try to update marks
+        and stuff if the backend didn't return the article number.  This fixes
+        an Exchange-related nnimap bug.
+
+        * gnus-sum.el (gnus-summary-next-article): Remove hack to reselect
+        group window, because it does the wrong thing when a separate frame
+        displays the group buffer.
+
+        * proto-stream.el (open-protocol-stream): Protect against the low-level
+        transport functions returning nil.
+
 2011-01-07  Daiki Ueno  <ueno@unixuser.org>
 
         * mml2015.el (epg-sub-key-fingerprint): Autoload.
diff --git a/lisp/gnus/gnus-int.el b/lisp/gnus/gnus-int.el
index 71a9aa9e618..b805167149f 100644
--- a/lisp/gnus/gnus-int.el
+++ b/lisp/gnus/gnus-int.el
@@ -1,7 +1,7 @@
 ;;; gnus-int.el --- backend interface functions for Gnus
 
 ;; Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004
-;;   2005, 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
+;;   2005, 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
 
 ;; Author: Lars Magne Ingebrigtsen <larsi@gnus.org>
 ;; Keywords: news
@@ -711,7 +711,9 @@ If GROUP is nil, all groups on GNUS-COMMAND-METHOD are scanned."
           (if (stringp group) (gnus-group-real-name group) group)
           (cadr gnus-command-method)
           last)))
-    (when (and gnus-agent (gnus-agent-method-p gnus-command-method))
+    (when (and gnus-agent
+               (gnus-agent-method-p gnus-command-method)
+               (cdr result))
       (gnus-agent-regenerate-group group (list (cdr result))))
     result))
 
diff --git a/lisp/gnus/gnus-sum.el b/lisp/gnus/gnus-sum.el
index 9a21a9c7f68..20a1141cc25 100644
--- a/lisp/gnus/gnus-sum.el
+++ b/lisp/gnus/gnus-sum.el
@@ -7687,9 +7687,6 @@ If BACKWARD, the previous article is selected instead of the next."
            (if (eq gnus-keep-same-level 'best)
                (gnus-summary-best-group gnus-newsgroup-name)
              (gnus-summary-search-group backward gnus-keep-same-level))))
-      ;; For some reason, the group window gets selected.  We change
-      ;; it back.
-      (select-window (get-buffer-window (current-buffer)))
       ;; Select next unread newsgroup automagically.
       (cond
        ((or (not gnus-auto-select-next)
diff --git a/lisp/gnus/mm-decode.el b/lisp/gnus/mm-decode.el
index 216ed6624d9..62755347142 100644
--- a/lisp/gnus/mm-decode.el
+++ b/lisp/gnus/mm-decode.el
@@ -1,7 +1,7 @@
 ;;; mm-decode.el --- Functions for decoding MIME things
 
 ;; Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006,
-;;   2007, 2008, 2009, 2010  Free Software Foundation, Inc.
+;;   2007, 2008, 2009, 2010, 2011  Free Software Foundation, Inc.
 
 ;; Author: Lars Magne Ingebrigtsen <larsi@gnus.org>
 ;;      MORIOKA Tomohiko <morioka@jaist.ac.jp>
@@ -1367,13 +1367,18 @@ Use CMD as the process."
 
 (defun mm-preferred-alternative-precedence (handles)
   "Return the precedence based on HANDLES and `mm-discouraged-alternatives'."
-  (let ((seq (nreverse (mapcar #'mm-handle-media-type
-                               handles))))
-    (dolist (disc (reverse mm-discouraged-alternatives))
-      (dolist (elem (copy-sequence seq))
-        (when (string-match disc elem)
-          (setq seq (nconc (delete elem seq) (list elem))))))
-    seq))
+  (setq handles (reverse handles))
+  (dolist (disc (reverse mm-discouraged-alternatives))
+    (dolist (handle (copy-sequence handles))
+      (when (string-match disc (mm-handle-media-type handle))
+        (setq handles (nconc (delete handle handles) (list handle))))))
+  ;; Remove empty parts.
+  (dolist (handle (copy-sequence handles))
+    (unless (with-current-buffer (mm-handle-buffer handle)
+              (goto-char (point-min))
+              (re-search-forward "[^ \t\n]" nil t))
+      (setq handles (nconc (delete handle handles) (list handle)))))
+  (mapcar #'mm-handle-media-type handles))
 
 (defun mm-get-content-id (id)
   "Return the handle(s) referred to by ID."
diff --git a/lisp/gnus/nnimap.el b/lisp/gnus/nnimap.el
index 51fa532a371..0c711701e96 100644
--- a/lisp/gnus/nnimap.el
+++ b/lisp/gnus/nnimap.el
@@ -582,7 +582,7 @@ textual parts.")
     ;; Collect all the body parts.
     (while (looking-at ".*BODY\\[\\([.0-9]+\\)\\]")
       (setq id (match-string 1)
-            bytes (nnimap-get-length))
+            bytes (or (nnimap-get-length) 0))
       (beginning-of-line)
       (delete-region (point) (progn (forward-line 1) (point)))
       (push (list id (buffer-substring (point) (+ (point) bytes)))
diff --git a/lisp/gnus/proto-stream.el b/lisp/gnus/proto-stream.el
index d1266cb5461..546461a67b3 100644
--- a/lisp/gnus/proto-stream.el
+++ b/lisp/gnus/proto-stream.el
@@ -1,6 +1,6 @@
 ;;; proto-stream.el --- negotiating TLS, STARTTLS and other connections
 
-;; Copyright (C) 2010 Free Software Foundation, Inc.
+;; Copyright (C) 2010, 2011 Free Software Foundation, Inc.
 
 ;; Author: Lars Magne Ingebrigtsen <larsi@gnus.org>
 ;; Keywords: network
@@ -101,14 +101,17 @@ command to switch on STARTTLS otherwise."
       (setq type 'network))
      ((eq type 'ssl)
       (setq type 'tls)))
-    (destructuring-bind (stream greeting capabilities)
-        (funcall (intern (format "proto-stream-open-%s" type) obarray)
-                 name buffer host service parameters)
-      (list (and stream
-                 (memq (process-status stream)
-                       '(open run))
-                 stream)
-            greeting capabilities))))
+    (let ((open-result
+           (funcall (intern (format "proto-stream-open-%s" type) obarray)
+                    name buffer host service parameters)))
+      (if (null open-result)
+          (list nil nil nil)
+        (destructuring-bind (stream greeting capabilities) open-result
+          (list (and stream
+                     (memq (process-status stream)
+                           '(open run))
+                     stream)
+                greeting capabilities))))))
 
 (defun proto-stream-open-network-only (name buffer host service parameters)
   (let ((start (with-current-buffer buffer (point)))