Good day,

Patch is a fix for a regression, which was introduced by the patch I
previously posted on this list (Date: Mon, 31 Oct 2011 09:56:58 +0600,
Subject: [PATCH] erc-dcc: allow SEND commands containing quoted
filenames with spaces in them).

As I see, it was picked up by Julien on Mon Nov 28 10:24:08 2011 +0100
in bb90806bc156833c (git://git.savannah.gnu.org/emacs.git).

Unfortunately, during one of the iterations of regexp-mangling, I
forgot to update match group number for *unquoted* filename matches,
thus introducing the regression.

Regexp in question is erc-dcc-ctcp-query-send-regexp and currently it
looks like this:

  (concat "^DCC SEND \\("
   ;; Following part matches either filename without spaces
   ;; or filename enclosed in double quotes with any number
   ;; of escaped double quotes inside.
   "\"\\(\\(.*?\\(\\\\\"\\)?\\)+?\\)\"\\|\\([^ ]+\\)"
   "\\) \\([0-9]+\\) \\([0-9]+\\) *\\([0-9]*\\)")

And the match is dissected like this:
 
  (let
    ((filename
      (or (match-string 3 query)
        (erc-dcc-unquote-filename (match-string 2 query))))
    (ip (erc-decimal-to-ip (match-string 6 query)))
    ...

As can be seen, though, unquoted filename is only matched by the fifth
regexp group ("|\\([^ ]+\\)" part), not third, thus matching of
unquoted filenames fails with non-descriptive nil-instead-of-string
error.

Issue was masked until now for me by custom (simplier hack)
erc-dcc-ctcp-query-send-regexp definition in my config, older emacs
version and relatively infrequent use of dcc with clients that don't
use filename-quoting.

Apologies to Julien and Michael for unasked-for CC, but I thought you
might be interested and should be notified, as people who reviewed the
initial patch.

Sorry for a lousy job of testing previous patch.
Thanks.


From e5fe5e71b0c7a898132dfce2a7ec72b8703079bd Mon Sep 17 00:00:00 2001
From: Mike Kazantsev <mk.fraggod@gmail.com>
Date: Wed, 9 May 2012 17:27:27 +0600
Subject: [PATCH] etc-dcc: Fix handling SEND commands with unquoted filename.

* erc-dcc.el (erc-dcc-handle-ctcp-send): Fix regexp match group numbers.

---
 lisp/erc/erc-dcc.el |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lisp/erc/erc-dcc.el b/lisp/erc/erc-dcc.el
index ba87cf6..d1ef1a9 100644
--- a/lisp/erc/erc-dcc.el
+++ b/lisp/erc/erc-dcc.el
@@ -674,7 +674,7 @@ It extracts the information about the dcc request and adds it to
        ?r "SEND" ?n nick ?u login ?h host))
      ((string-match erc-dcc-ctcp-query-send-regexp query)
       (let ((filename
-             (or (match-string 3 query)
+             (or (match-string 5 query)
                  (erc-dcc-unquote-filename (match-string 2 query))))
             (ip       (erc-decimal-to-ip (match-string 6 query)))
             (port     (match-string 7 query))
-- 
1.7.10


-- 
Mike Kazantsev // fraggod.net