bug#19192: 25.0.50; TRAMP uses `dired-listing-switches' for ftp-connection

bug#19192: 25.0.50; TRAMP uses `dired-listing-switches' for ftp-connection

[Rasmus]

Hi,

I want to use TRAMP for editing files over ftp.

I my init.el I have augmented `dired-listing-switches' with
"--group-directories-first" to get a more pleasing listing in dired.
However, this extra flag is added to whatever tramp calls to connect to
ftp.  So in the ftp buffer I see something like this:

ftp> ls -al --group-directories-first /tmp/ange-ftp19481AaR
     usage: ls remote-directory local-file

When I wrap find-file in a `let' with dired-listing-switches set to
"-al" everything works as expected.

I don't know if this is a feature or a bug.

Michael: do you want me to write a patch or will this be a quick fix for
you?

Thanks,
Rasmus

In GNU Emacs 25.0.50.1 (x86_64-unknown-linux-gnu, GTK+ Version 3.14.5)
 of 2014-11-25 on W530
Repository revision: 27f46ae31cd289dbff4c521fcf37a1d048693f6e
Windowing system distributor `The X.Org Foundation', version 11.0.11602000
System Description:	Arch Linux

Configured using:
 `configure --prefix=/usr --sysconfdir=/etc --localstatedir=/var
 --libexecdir=/usr/lib --mandir=/usr/share/man --without-sound
 --with-xft --with-x-toolkit=gtk3 'CFLAGS=-march=x86-64 -mtune=generic
 -O2 -pipe -fstack-protector --param=ssp-buffer-size=4'
 'LDFLAGS=-lMagickWand-6.Q16HDRI -lMagickCore-6.Q16HDRI '
 CPPFLAGS=-D_FORTIFY_SOURCE=2'

Configured features:
XPM JPEG TIFF GIF PNG RSVG IMAGEMAGICK GPM DBUS GCONF GSETTINGS NOTIFY
ACL GNUTLS LIBXML2 FREETYPE M17N_FLT LIBOTF XFT ZLIB

Important settings:
  value of $LANG: es_ES.utf8
  locale-coding-system: utf-8-unix

Major mode: Emacs-Lisp

Minor modes in effect:
  recentf-mode: t
  diff-auto-refine-mode: t
  nyan-mode: t
  paredit-mode: t
  flyspell-mode: t
  subword-mode: t
  shell-dirtrack-mode: t
  global-company-mode: t
  company-mode: t
  ido-everywhere: t
  global-auto-revert-mode: t
  which-function-mode: t
  winner-mode: t
  delete-selection-mode: t
  show-paren-mode: t
  electric-pair-mode: t
  savehist-mode: t
  tooltip-mode: t
  global-eldoc-mode: t
  eldoc-mode: t
  electric-layout-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  prettify-symbols-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  column-number-mode: t
  line-number-mode: t
  global-visual-line-mode: t
  visual-line-mode: t

Recent messages:
Auto-saving...done
Deleting escape.
paredit-backslash-interactive: Wrong type argument: characterp, 134217830
Character to escape: \
Doing CD...done
Listing /ftp:rasmus@ssl.eumx.net:/... [2 times]
Doing CD...done
Listing /ftp:rasmus@ssl.eumx.net:/... [2 times]
tramp-file-name-handler: FTP Error: DIR failed: usage: ls remote-directory local-file
Undo!

Load-path shadows:
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Features:
(shadow emacsbug debug ange-ftp tramp-ftp vc-git ffap thingatpt recentf
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-- 
With monopolies the cake is a lie!

bug#19192: 25.0.50; TRAMP uses `dired-listing-switches' for ftp-connection

[Michael Albinus]

Rasmus <rasmus@gmx.us> writes:

> Hi,

Hi Rasmus,

> I don't know if this is a feature or a bug.
>
> Michael: do you want me to write a patch or will this be a quick fix for
> you?

Likely, it is a feature. So I don't know whether we can fix this quickly.

However, if you want to investigate it, it is likely in
ange-ftp.el. Tramp doesn't care about ftp connections, it let
ange-ftp.el do the job.

A possible fix might be to give a user an option, whether global
dired-listing-switches shall be used everywhere, or whether there shall
be special settings connection-oriented.

> Thanks,
> Rasmus

Best regards, Michael.

bug#19192: 25.0.50; TRAMP uses `dired-listing-switches' for ftp-connection

[Rasmus]

Hi,

Michael Albinus <michael.albinus@gmx.de> writes:

> Rasmus <rasmus@gmx.us> writes:
>> I don't know if this is a feature or a bug.
>>
>> Michael: do you want me to write a patch or will this be a quick fix for
>> you?
>
> Likely, it is a feature. So I don't know whether we can fix this quickly.

I agree.

> However, if you want to investigate it, it is likely in
> ange-ftp.el. Tramp doesn't care about ftp connections, it let
> ange-ftp.el do the job.

Thanks for pointing this out.

> A possible fix might be to give a user an option, whether global
> dired-listing-switches shall be used everywhere, or whether there shall
> be special settings connection-oriented.

So it turns out that arguments are tested via `ange-ftp-switches-ok'.
So the easiest fix would probably be to extend this function to do a
better job of checking.  Unfortunately, I don't know if one can easily
predict which ls commands will be understood and which not?  E.g. does
ftp ls depend on the host systems version of ls?

Thanks,
Rasmus

-- 
Summon the Mothership!

bug#19192: 25.0.50; TRAMP uses `dired-listing-switches' for ftp-connection

[Michael Albinus]

Rasmus <rasmus@gmx.us> writes:

> Hi,

Hi Rasmus,

>> A possible fix might be to give a user an option, whether global
>> dired-listing-switches shall be used everywhere, or whether there shall
>> be special settings connection-oriented.
>
> So it turns out that arguments are tested via `ange-ftp-switches-ok'.
> So the easiest fix would probably be to extend this function to do a
> better job of checking.  Unfortunately, I don't know if one can easily
> predict which ls commands will be understood and which not?  E.g. does
> ftp ls depend on the host systems version of ls?

I don't know exactly. But I guess the most stable patch would be to not
expect too much from ftp's ls.

> Thanks,
> Rasmus

Best regards, Michael.

bug#19192: 25.0.50; TRAMP uses `dired-listing-switches' for ftp-connection

[Rasmus]

Hi,

Sorry for asking so many questions.

Michael Albinus <michael.albinus@gmx.de> writes:

> Rasmus <rasmus@gmx.us> writes:
>>> A possible fix might be to give a user an option, whether global
>>> dired-listing-switches shall be used everywhere, or whether there shall
>>> be special settings connection-oriented.
>>
>> So it turns out that arguments are tested via `ange-ftp-switches-ok'.
>> So the easiest fix would probably be to extend this function to do a
>> better job of checking.  Unfortunately, I don't know if one can easily
>> predict which ls commands will be understood and which not?  E.g. does
>> ftp ls depend on the host systems version of ls?
>
> I don't know exactly. But I guess the most stable patch would be to not
> expect too much from ftp's ls.

So according to the note in `ange-ftp-get-files' there's the following
node on using dired-actual-switches or dired-listing-switches

    ;; This is an efficiency hack. We try to
    ;; anticipate what sort of listing dired
    ;; might want, and cache just such a listing.

Switches are checked with `ange-ftp-switches-ok'.  (man "sftp") has a nice list of
switches supported.  Unfortunately, I don't really find anything on
supported ls in the manpage of ftp or the info manual...

Option I: I can limit accepted ls flags by ange-ftp to the subset
supported by sftp.  

Option I+: I could add a defcustom to allow the current more liberal
behavior akin to ange-ftp-passive-host-alist and
ange-ftp-try-passive-mode.

Option II would be to add build-in support for something like the
--group-directories-first in dired, since now, if scrub off
--group-directories-first, a dired-ftp buffer will look different from a
local dired buffer...

For now I will go with Option I.

Thanks,
Rasmus

-- 
The Kids call him Billy the Saint

bug#19192: 25.0.50; TRAMP uses `dired-listing-switches' for ftp-connection

[Rasmus]

[-- Attachment #1: Type: text/plain, Size: 642 bytes --]

Rasmus <rasmus@gmx.us> writes:

> For now I will go with Option I.

Well, turned out to be a bad idea.  Instead I tested all flags in (man
"ls") and exclude the flags that caused trouble.  Note, I only have one
ftp to test against. . .  I'm assuming this one is somewhat common.

Also, a limitation of the `ange-ftp-switches-ok' is that it's too
destructive: I.e. rather than removing offending ls-flags, it will
entirely disregard the whole thing.  I guess that's another patch,
though.

If you find the patch OK, feel free to submit.  Otherwise, let me know
what to improve.

Thanks,
Rasmus

-- 
The right to be left alone is a human right

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #2: 0001-ange-ftp.el-Disallow-more-dired-ls-flags.patch --]
[-- Type: text/x-diff, Size: 2545 bytes --]

From 6fd921e7d7deb88c5a3f172022b64a0539edbdd6 Mon Sep 17 00:00:00 2001
From: Rasmus <w530@pank.eu>
Date: Sat, 29 Nov 2014 13:12:10 +0100
Subject: [PATCH] ange-ftp.el: Disallow more dired ls-flags

* net/ange-ftp.el (ange-ftp-switches-ok): Disallow flags causing
trouble with ls over ftp.  These flags result in ls returning no
output, causing Tramp-breakage.

Fixes: debbugs:19192
---
 lisp/ChangeLog       |  6 ++++++
 lisp/net/ange-ftp.el | 12 +++++++++++-
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 2a450a7..7d0992e 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,9 @@
+2014-11-29  Rasmus Pank Roulund  <emacs@pank.eu>
+
+	* net/ange-ftp.el (ange-ftp-switches-ok): Disallow flags causing
+	trouble with ls over ftp.  These flags result in ls returning no
+	output, causing Tramp-breakage.  (bug#19192)
+
 2014-11-29  Stephen Berman  <stephen.berman@gmx.net>
 	    Stefan Monnier  <monnier@iro.umontreal.ca>
 
diff --git a/lisp/net/ange-ftp.el b/lisp/net/ange-ftp.el
index d7632ed..a2b0b46 100644
--- a/lisp/net/ange-ftp.el
+++ b/lisp/net/ange-ftp.el
@@ -2831,16 +2831,26 @@ match subdirectories as well.")
 		      files ange-ftp-files-hashtable)))
 
 (defun ange-ftp-switches-ok (switches)
-  "Return SWITCHES (a string) if suitable for our use."
+  "Return SWITCHES (a string) if suitable for use with ls over ftp."
   (and (stringp switches)
        ;; We allow the A switch, which lists all files except "." and
        ;; "..".  This is OK because we manually insert these entries
        ;; in the hash table.
        (string-match
 	"--\\(almost-\\)?all\\>\\|\\(\\`\\| \\)-[[:alpha:]]*[aA]" switches)
+       ;; Allow flags starting with a single dash
        (string-match "\\(\\`\\| \\)-[[:alpha:]]*l" switches)
+       ;; Disallow recursive flag
        (not (string-match
 	     "--recursive\\>\\|\\(\\`\\| \\)-[[:alpha:]]*R" switches))
+       ;; Disallow most long flags from (man "ls"), version 8.23 of July 2014.
+       (not (string-match
+             (concat
+              "--\\(block-size\\|color\\|format\\|group-directories-first\\|"
+              "human-readable\\|dereference-command-line\\|hide\\|indicator-style\\|"
+              "dereference-command-line-symlink-to-dir\\|inode\\|ignore\\|dereference\\|"
+              "numeric-uid-gid\\|indicator-style\\|hide-control-chars\\|quoting-style\\|"
+              "sort\\|time\\|time-style\\|width\\)")))
        switches))
 
 (defun ange-ftp-get-files (directory &optional no-error)
-- 
2.1.3

bug#19192: 25.0.50; TRAMP uses `dired-listing-switches' for ftp-connection

[Rasmus]

[-- Attachment #1: Type: text/plain, Size: 782 bytes --]

Rasmus <rasmus@gmx.us> writes:

> Rasmus <rasmus@gmx.us> writes:
>
>> For now I will go with Option I.
>
> Well, turned out to be a bad idea.  Instead I tested all flags in (man
> "ls") and exclude the flags that caused trouble.  Note, I only have one
> ftp to test against. . .  I'm assuming this one is somewhat common.
>
> Also, a limitation of the `ange-ftp-switches-ok' is that it's too
> destructive: I.e. rather than removing offending ls-flags, it will
> entirely disregard the whole thing.  I guess that's another patch,
> though.
>
> If you find the patch OK, feel free to submit.  Otherwise, let me know
> what to improve.

This patch uses the "right" email for the commit (I don't know if this
matters much).  Otherwise identical.

-- 
The Kids call him Billy the Saint

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #2: 0001-ange-ftp.el-Disallow-more-dired-ls-flags.patch --]
[-- Type: text/x-diff, Size: 2549 bytes --]

From 6fd921e7d7deb88c5a3f172022b64a0539edbdd6 Mon Sep 17 00:00:00 2001
From: Rasmus <w530@pank.eu>
Date: Sat, 29 Nov 2014 13:12:10 +0100
Subject: [PATCH 1/2] ange-ftp.el: Disallow more dired ls-flags

* net/ange-ftp.el (ange-ftp-switches-ok): Disallow flags causing
trouble with ls over ftp.  These flags result in ls returning no
output, causing Tramp-breakage.

Fixes: debbugs:19192
---
 lisp/ChangeLog       |  6 ++++++
 lisp/net/ange-ftp.el | 12 +++++++++++-
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 2a450a7..7d0992e 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,9 @@
+2014-11-29  Rasmus Pank Roulund  <emacs@pank.eu>
+
+	* net/ange-ftp.el (ange-ftp-switches-ok): Disallow flags causing
+	trouble with ls over ftp.  These flags result in ls returning no
+	output, causing Tramp-breakage.  (bug#19192)
+
 2014-11-29  Stephen Berman  <stephen.berman@gmx.net>
 	    Stefan Monnier  <monnier@iro.umontreal.ca>
 
diff --git a/lisp/net/ange-ftp.el b/lisp/net/ange-ftp.el
index d7632ed..a2b0b46 100644
--- a/lisp/net/ange-ftp.el
+++ b/lisp/net/ange-ftp.el
@@ -2831,16 +2831,26 @@ match subdirectories as well.")
 		      files ange-ftp-files-hashtable)))
 
 (defun ange-ftp-switches-ok (switches)
-  "Return SWITCHES (a string) if suitable for our use."
+  "Return SWITCHES (a string) if suitable for use with ls over ftp."
   (and (stringp switches)
        ;; We allow the A switch, which lists all files except "." and
        ;; "..".  This is OK because we manually insert these entries
        ;; in the hash table.
        (string-match
 	"--\\(almost-\\)?all\\>\\|\\(\\`\\| \\)-[[:alpha:]]*[aA]" switches)
+       ;; Allow flags starting with a single dash
        (string-match "\\(\\`\\| \\)-[[:alpha:]]*l" switches)
+       ;; Disallow recursive flag
        (not (string-match
 	     "--recursive\\>\\|\\(\\`\\| \\)-[[:alpha:]]*R" switches))
+       ;; Disallow most long flags from (man "ls"), version 8.23 of July 2014.
+       (not (string-match
+             (concat
+              "--\\(block-size\\|color\\|format\\|group-directories-first\\|"
+              "human-readable\\|dereference-command-line\\|hide\\|indicator-style\\|"
+              "dereference-command-line-symlink-to-dir\\|inode\\|ignore\\|dereference\\|"
+              "numeric-uid-gid\\|indicator-style\\|hide-control-chars\\|quoting-style\\|"
+              "sort\\|time\\|time-style\\|width\\)")))
        switches))
 
 (defun ange-ftp-get-files (directory &optional no-error)
-- 
2.1.3

bug#19192: 25.0.50; TRAMP uses `dired-listing-switches' for ftp-connection

[Michael Albinus]

Rasmus <rasmus@gmx.us> writes:

> Hi,

Hi,

> Sorry for asking so many questions.

No problem. That's why we have debbugs that we can discuss the problem.

> So according to the note in `ange-ftp-get-files' there's the following
> node on using dired-actual-switches or dired-listing-switches
>
>     ;; This is an efficiency hack. We try to
>     ;; anticipate what sort of listing dired
>     ;; might want, and cache just such a listing.
>
> Switches are checked with `ange-ftp-switches-ok'.  (man "sftp") has a
> nice list of
> switches supported.  Unfortunately, I don't really find anything on
> supported ls in the manpage of ftp or the info manual...
>
> Option I: I can limit accepted ls flags by ange-ftp to the subset
> supported by sftp.  
>
> Option I+: I could add a defcustom to allow the current more liberal
> behavior akin to ange-ftp-passive-host-alist and
> ange-ftp-try-passive-mode.
>
> Option II would be to add build-in support for something like the
> --group-directories-first in dired, since now, if scrub off
> --group-directories-first, a dired-ftp buffer will look different from a
> local dired buffer...
>
> For now I will go with Option I.

Well, I'm a little bit confused. In the beginning, you have spoken about
"ftp". Now you've switched to "sftp". These are very different cases,
and ange-ftp.el is *not* responsible for sftp connections.

Could you, please, clarify?

> Thanks,
> Rasmus

Best regards, Michael.

bug#19192: 25.0.50; TRAMP uses `dired-listing-switches' for ftp-connection

[Rasmus]

[-- Attachment #1: Type: text/plain, Size: 1676 bytes --]

Hi,

Michael Albinus <michael.albinus@gmx.de> writes:

>> So according to the note in `ange-ftp-get-files' there's the following
>> node on using dired-actual-switches or dired-listing-switches
>>
>>     ;; This is an efficiency hack. We try to
>>     ;; anticipate what sort of listing dired
>>     ;; might want, and cache just such a listing.
>>
>> Switches are checked with `ange-ftp-switches-ok'.  (man "sftp") has a
>> nice list of
>> switches supported.  Unfortunately, I don't really find anything on
>> supported ls in the manpage of ftp or the info manual...
>>
>> Option I: I can limit accepted ls flags by ange-ftp to the subset
>> supported by sftp.  
>>
>> Option I+: I could add a defcustom to allow the current more liberal
>> behavior akin to ange-ftp-passive-host-alist and
>> ange-ftp-try-passive-mode.
>>
>> Option II would be to add build-in support for something like the
>> --group-directories-first in dired, since now, if scrub off
>> --group-directories-first, a dired-ftp buffer will look different from a
>> local dired buffer...
>>
>> For now I will go with Option I.
>
> Well, I'm a little bit confused. In the beginning, you have spoken about
> "ftp". Now you've switched to "sftp". These are very different cases,
> and ange-ftp.el is *not* responsible for sftp connections.
>
> Could you, please, clarify?

That comment is obsolete.  See why here:

     http://debbugs.gnu.org/cgi/bugreport.cgi?bug=19192#20

I tried all long commands with my ftp server (Debian-hosted) and discard
the ones that breaks ls over ftp.  

Feel free to try the attached patch.

Cheers,
Rasmus

-- 
If you can mix business and politics wonderful things can happen!

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #2: 0001-ange-ftp.el-Disallow-more-dired-ls-flags.patch --]
[-- Type: text/x-diff, Size: 2541 bytes --]

From 6fd921e7d7deb88c5a3f172022b64a0539edbdd6 Mon Sep 17 00:00:00 2001
From: Rasmus <rasmus@gmx.us>
Date: Sat, 29 Nov 2014 13:12:10 +0100
Subject: [PATCH] ange-ftp.el: Disallow more dired ls-flags

* net/ange-ftp.el (ange-ftp-switches-ok): Disallow flags causing
trouble with ls over ftp.  These flags result in ls returning no
output, causing Tramp-breakage.

Fixes: debbugs:19192
---
 lisp/ChangeLog       |  6 ++++++
 lisp/net/ange-ftp.el | 12 +++++++++++-
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 2a450a7..7d0992e 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,9 @@
+2014-11-29  Rasmus Pank Roulund  <emacs@pank.eu>
+
+	* net/ange-ftp.el (ange-ftp-switches-ok): Disallow flags causing
+	trouble with ls over ftp.  These flags result in ls returning no
+	output, causing Tramp-breakage.  (bug#19192)
+
 2014-11-29  Stephen Berman  <stephen.berman@gmx.net>
 	    Stefan Monnier  <monnier@iro.umontreal.ca>

diff --git a/lisp/net/ange-ftp.el b/lisp/net/ange-ftp.el
index d7632ed..a2b0b46 100644
--- a/lisp/net/ange-ftp.el
+++ b/lisp/net/ange-ftp.el
@@ -2831,16 +2831,26 @@ match subdirectories as well.")
 		      files ange-ftp-files-hashtable)))

 (defun ange-ftp-switches-ok (switches)
-  "Return SWITCHES (a string) if suitable for our use."
+  "Return SWITCHES (a string) if suitable for use with ls over ftp."
   (and (stringp switches)
        ;; We allow the A switch, which lists all files except "." and
        ;; "..".  This is OK because we manually insert these entries
        ;; in the hash table.
        (string-match
 	"--\\(almost-\\)?all\\>\\|\\(\\`\\| \\)-[[:alpha:]]*[aA]" switches)
+       ;; Allow flags starting with a single dash
        (string-match "\\(\\`\\| \\)-[[:alpha:]]*l" switches)
+       ;; Disallow recursive flag
        (not (string-match
 	     "--recursive\\>\\|\\(\\`\\| \\)-[[:alpha:]]*R" switches))
+       ;; Disallow most long flags from (man "ls"), version 8.23 of July 2014.
+       (not (string-match
+             (concat
+              "--\\(block-size\\|color\\|format\\|group-directories-first\\|"
+              "human-readable\\|dereference-command-line\\|hide\\|indicator-style\\|"
+              "dereference-command-line-symlink-to-dir\\|inode\\|ignore\\|dereference\\|"
+              "numeric-uid-gid\\|indicator-style\\|hide-control-chars\\|quoting-style\\|"
+              "sort\\|time\\|time-style\\|width\\)")))
        switches))

 (defun ange-ftp-get-files (directory &optional no-error)
--
2.1.3

bug#19192: 25.0.50; TRAMP uses `dired-listing-switches' for ftp-connection

[Michael Albinus]

Rasmus <rasmus@gmx.us> writes:

> Hi,

Hi Rasmus,

> That comment is obsolete.  See why here:
>
>      http://debbugs.gnu.org/cgi/bugreport.cgi?bug=19192#20
>
> I tried all long commands with my ftp server (Debian-hosted) and discard
> the ones that breaks ls over ftp.  
>
> Feel free to try the attached patch.

Sorry, it took a while until I found the time to have a look on your
patch.

So far it seems to be OK, but wouldn't it be safer to disallow all
options to ftp which start with "--"? I understand that you have checked
it with your ftp client, but you cannot assume that everybody uses the same
version of ftp and ls as you do. Samr for the ftp server.

> Cheers,
> Rasmus

Best regards, Michael.

bug#19192: 25.0.50; TRAMP uses `dired-listing-switches' for ftp-connection

[Rasmus]

[-- Attachment #1: Type: text/plain, Size: 561 bytes --]

Michael Albinus <michael.albinus@gmx.de> writes:

> So far it seems to be OK, but wouldn't it be safer to disallow all
> options to ftp which start with "--"? I understand that you have checked
> it with your ftp client, but you cannot assume that everybody uses the same
> version of ftp and ls as you do. Samr for the ftp server.

As you prefer.  

This patch disallow
   (string-match "--\\w\\{2,\\}" switches)
which should be enough to capture switches starting with --, I guess.

—Rasmus

-- 
The right to be left alone is a human right

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #2: 0001-ange-ftp.el-Disallow-more-dired-ls-flags.patch --]
[-- Type: text/x-diff, Size: 2134 bytes --]

From 55bf708060ddf05a87df4f1f22185aceac74d9c6 Mon Sep 17 00:00:00 2001
From: Rasmus <rasmus@gmx.us>
Date: Sat, 29 Nov 2014 13:12:10 +0100
Subject: [PATCH] ange-ftp.el: Disallow more dired ls-flags

* net/ange-ftp.el (ange-ftp-switches-ok): Disallow flags causing
trouble with ls over ftp.  These flags result in ls returning no
output, causing Tramp-breakage.

Fixes: debbugs:19192
---
 lisp/ChangeLog       | 6 ++++++
 lisp/net/ange-ftp.el | 8 ++++++--
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 454ee00..09b64f5 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,9 @@
+2014-11-29  Rasmus Pank Roulund  <emacs@pank.eu>
+
+	* net/ange-ftp.el (ange-ftp-switches-ok): Disallow flags causing
+	trouble with ls over ftp.  These flags result in ls returning no
+	output, causing Tramp-breakage.  (bug#19192)
+
 2014-12-10  Andreas Schwab  <schwab@suse.de>
 
 	* files.el (file-tree-walk): Use file-name-as-directory
diff --git a/lisp/net/ange-ftp.el b/lisp/net/ange-ftp.el
index d7632ed..5e9bc27 100644
--- a/lisp/net/ange-ftp.el
+++ b/lisp/net/ange-ftp.el
@@ -2831,16 +2831,20 @@ match subdirectories as well.")
 		      files ange-ftp-files-hashtable)))
 
 (defun ange-ftp-switches-ok (switches)
-  "Return SWITCHES (a string) if suitable for our use."
+  "Return SWITCHES (a string) if suitable for use with ls over ftp."
   (and (stringp switches)
        ;; We allow the A switch, which lists all files except "." and
        ;; "..".  This is OK because we manually insert these entries
        ;; in the hash table.
        (string-match
 	"--\\(almost-\\)?all\\>\\|\\(\\`\\| \\)-[[:alpha:]]*[aA]" switches)
+       ;; Allow flags starting with a single dash
        (string-match "\\(\\`\\| \\)-[[:alpha:]]*l" switches)
+       ;; Disallow recursive flag
        (not (string-match
-	     "--recursive\\>\\|\\(\\`\\| \\)-[[:alpha:]]*R" switches))
+	     "\\(\\`\\| \\)-[[:alpha:]]*R" switches))
+       ;; Disallow long flags.
+       (not (string-match "--\\w\\{2,\\}"))
        switches))
 
 (defun ange-ftp-get-files (directory &optional no-error)
-- 
2.1.3

bug#19192: 25.0.50; TRAMP uses `dired-listing-switches' for ftp-connection

[Andreas Schwab]

Rasmus <rasmus@gmx.us> writes:

> diff --git a/lisp/net/ange-ftp.el b/lisp/net/ange-ftp.el
> index d7632ed..5e9bc27 100644
> --- a/lisp/net/ange-ftp.el
> +++ b/lisp/net/ange-ftp.el
> @@ -2831,16 +2831,20 @@ match subdirectories as well.")
>  		      files ange-ftp-files-hashtable)))
>  
>  (defun ange-ftp-switches-ok (switches)
> -  "Return SWITCHES (a string) if suitable for our use."
> +  "Return SWITCHES (a string) if suitable for use with ls over ftp."
>    (and (stringp switches)
>         ;; We allow the A switch, which lists all files except "." and
>         ;; "..".  This is OK because we manually insert these entries
>         ;; in the hash table.
>         (string-match
>  	"--\\(almost-\\)?all\\>\\|\\(\\`\\| \\)-[[:alpha:]]*[aA]" switches)
> +       ;; Allow flags starting with a single dash
>         (string-match "\\(\\`\\| \\)-[[:alpha:]]*l" switches)
> +       ;; Disallow recursive flag
>         (not (string-match
> -	     "--recursive\\>\\|\\(\\`\\| \\)-[[:alpha:]]*R" switches))
> +	     "\\(\\`\\| \\)-[[:alpha:]]*R" switches))
> +       ;; Disallow long flags.
> +       (not (string-match "--\\w\\{2,\\}"))

This contradicts the first string-match.

-- 
Andreas Schwab, SUSE Labs, schwab@suse.de
GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE  1748 E4D4 88E3 0EEA B9D7
"And now for something completely different."

bug#19192: 25.0.50; TRAMP uses `dired-listing-switches' for ftp-connection

[Rasmus]

[-- Attachment #1: Type: text/plain, Size: 1574 bytes --]

Andreas Schwab <schwab@suse.de> writes:

> Rasmus <rasmus@gmx.us> writes:
>
>> diff --git a/lisp/net/ange-ftp.el b/lisp/net/ange-ftp.el
>> index d7632ed..5e9bc27 100644
>> --- a/lisp/net/ange-ftp.el
>> +++ b/lisp/net/ange-ftp.el
>> @@ -2831,16 +2831,20 @@ match subdirectories as well.")
>>  		      files ange-ftp-files-hashtable)))
>>  
>>  (defun ange-ftp-switches-ok (switches)
>> -  "Return SWITCHES (a string) if suitable for our use."
>> +  "Return SWITCHES (a string) if suitable for use with ls over ftp."
>>    (and (stringp switches)
>>         ;; We allow the A switch, which lists all files except "." and
>>         ;; "..".  This is OK because we manually insert these entries
>>         ;; in the hash table.
>>         (string-match
>>  	"--\\(almost-\\)?all\\>\\|\\(\\`\\| \\)-[[:alpha:]]*[aA]" switches)
>> +       ;; Allow flags starting with a single dash
>>         (string-match "\\(\\`\\| \\)-[[:alpha:]]*l" switches)
>> +       ;; Disallow recursive flag
>>         (not (string-match
>> -	     "--recursive\\>\\|\\(\\`\\| \\)-[[:alpha:]]*R" switches))
>> +	     "\\(\\`\\| \\)-[[:alpha:]]*R" switches))
>> +       ;; Disallow long flags.
>> +       (not (string-match "--\\w\\{2,\\}"))
>
> This contradicts the first string-match.

You are right.

How about this one: allow --(almost-)all for legacy reasons.  Disallow
other long flags.  Allow short flag as long as their is an "l" and not an
"R"?  (At least that was the intention).

—Rasmus

-- 
Together we will make the possible totalllly impossible!

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
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From 07f99a06a30e271989a27dc58a2db54602d60e51 Mon Sep 17 00:00:00 2001
From: rasmus <x200s@pank.eu>
Date: Wed, 10 Dec 2014 16:18:00 +0100
Subject: [PATCH] ange-ftp.el: Disallow more dired ls-flags

* net/ange-ftp.el (ange-ftp-switches-ok): Disallow most lonng flags,
  as they may cause Tramp-breakage.

Fixes: debbugs:19192
---
 lisp/ChangeLog       |  6 ++++++
 lisp/net/ange-ftp.el | 20 ++++++++++++++------
 2 files changed, 20 insertions(+), 6 deletions(-)

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 454ee00..09b64f5 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,9 @@
+2014-11-29  Rasmus Pank Roulund  <emacs@pank.eu>
+
+	* net/ange-ftp.el (ange-ftp-switches-ok): Disallow flags causing
+	trouble with ls over ftp.  These flags result in ls returning no
+	output, causing Tramp-breakage.  (bug#19192)
+
 2014-12-10  Andreas Schwab  <schwab@suse.de>
 
 	* files.el (file-tree-walk): Use file-name-as-directory
diff --git a/lisp/net/ange-ftp.el b/lisp/net/ange-ftp.el
index d7632ed..db79c0d 100644
--- a/lisp/net/ange-ftp.el
+++ b/lisp/net/ange-ftp.el
@@ -2831,16 +2831,24 @@ match subdirectories as well.")
 		      files ange-ftp-files-hashtable)))
 
 (defun ange-ftp-switches-ok (switches)
-  "Return SWITCHES (a string) if suitable for our use."
+  "Return SWITCHES (a string) if suitable for use with ls over ftp."
   (and (stringp switches)
-       ;; We allow the A switch, which lists all files except "." and
-       ;; "..".  This is OK because we manually insert these entries
-       ;; in the hash table.
+       ;; We allow the --almost-all switch, which lists all files
+       ;; except "." and "..".  This is OK because we manually
+       ;; insert these entries in the hash table.
        (string-match
-	"--\\(almost-\\)?all\\>\\|\\(\\`\\| \\)-[[:alpha:]]*[aA]" switches)
+        "--\\(almost-\\)?all\\>\\|\\(\\`\\| \\)-[[:alpha:]]*[aA]"
+        switches)
+       ;; Disallow other long flags except --(almost-)all.
+       (not (string-match "\\(\\`\\| \\)--\\w+"
+                          (replace-regexp-in-string
+                           "--\\(almost-\\)?all\\>" ""
+                           switches)))
+       ;; Must include 'l'.
        (string-match "\\(\\`\\| \\)-[[:alpha:]]*l" switches)
+       ;; Disallow recursive flag.
        (not (string-match
-	     "--recursive\\>\\|\\(\\`\\| \\)-[[:alpha:]]*R" switches))
+             "\\(\\`\\| \\)-[[:alpha:]]*R" switches))
        switches))
 
 (defun ange-ftp-get-files (directory &optional no-error)
-- 
2.1.3

bug#19192: 25.0.50; TRAMP uses `dired-listing-switches' for ftp-connection

[Michael Albinus]

Rasmus <rasmus@gmx.us> writes:

> How about this one: allow --(almost-)all for legacy reasons.  Disallow
> other long flags.  Allow short flag as long as their is an "l" and not an
> "R"?  (At least that was the intention).

Looks good. I've committed it to the trunk, closing the bug.

> —Rasmus

Thanks, and best regards, Michael.