bug#17238: 24.3; TRAMP Can't open remote file with '$' in the filename

bug#17238: 24.3; TRAMP Can't open remote file with '$' in the filename

[Dana Pieluszczak]

[-- Attachment #1.1: Type: text/plain, Size: 4608 bytes --]

Preconditions

- A linux host which you have ssh access to (192.168.1.105 in the example
below)
- An account on said host
- SHELL on the remote host is /bin/bash (GNU bash, version
4.2.25(1)-release (i686-pc-linux-gnu)

Reproduction steps

$ ssh dana@192.168.1.105 'echo "some content" > /home/dana/t\$test.txt'
# verify there's some content in the file
$ ssh dana@192.168.1.105 'cat /home/dana/t\$test.txt'
$ emacs -Q -nw
# now we're in emacs
C-x C-f DEL DEL /dana@192.168.1.105:/home/dana/t$test.txt RET

Expected result

- a new buffer called t$test.txt is opened visiting the remote file

Actual result

- a new buffer called t$test.txt is opened
- the buffer is empty
- The following is written to *Messages* buffer:
  File exists, but cannot be read

This is a bug in tramp-sh-handle-file-truename. I've attached a
patch. The current version of tramp-sh-handle-file-truename uses
backticks inside a quoted string. Shell arguments used inside the
backticks should be shell escaped twice, but they're not.

I've changed the shell command to use a subshell ( $(...) )
Instead of backticks which removes the need for the double escaping.


I've done my best to follow the guidelines for reporting a bug and

submitting a patch. I'll be happy to fix up whatever is necessary to get

this accepted.


Dana P


If Emacs crashed, and you have the Emacs process in the gdb debugger,

please include the output from the following gdb commands:

    `bt full' and `xbacktrace'.

For information about debugging Emacs, please read the file

/Applications/Emacs.app/Contents/Resources/etc/DEBUG.



In GNU Emacs 24.3.1 (x86_64-apple-darwin, NS apple-appkit-1038.36)

 of 2013-03-13 on bob.porkrind.org

Windowing system distributor `Apple', version 10.3.1265

Configured using:

 `configure '--host=x86_64-apple-darwin' '--build=i686-apple-darwin'

 '--with-ns' 'build_alias=i686-apple-darwin'

 'host_alias=x86_64-apple-darwin' 'CC=gcc -mmacosx-version-min=10.7

 -isystem

 /Users/david/Xcode-10.7_4.5.2/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.7.sdk/usr/include/

 -F/Users/david/Xcode-10.7_4.5.2/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.7.sdk/System/Library/Frameworks''


Important settings:

  value of $LANG: en_US.UTF-8

  locale-coding-system: utf-8-unix

  default enable-multibyte-characters: t


Major mode: Text

Minor modes in effect:

  shell-dirtrack-mode: t

  tooltip-mode: t

  mouse-wheel-mode: t

  tool-bar-mode: t

  menu-bar-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

  buffer-read-only: t

  line-number-mode: t

  transient-mark-mode: t


Recent input:

ESC [ ? 1 ; 2 c C-x C-f DEL DEL / d a n a @ 1 9 2 .

1 6 8 . 1 . 1 0 1 DEL 5 : t DEL / h o m e / d a n a

/ t $ t e s t . t x t RET ESC x r e p o r t TAB RE

T


Recent messages:

Tramp: Opening connection for dana@192.168.1.105 using scpc...done

Tramp: Inserting `/scpc:dana@192.168.1.105:/home/dana/t$test.txt'...done

File exists, but cannot be read


Tramp: Checking `vc-registered' for /scpc:dana@192.168.1.105:
/home/dana/t$test.txt...done

File exists, but cannot be read


Tramp: Checking `vc-registered' for /scpc:dana@192.168.1.105:
/home/dana/t.txt...done

File exists, but cannot be read

current-kill: Kill ring is empty


Load-path shadows:

None found.

Features:

(shadow sort mail-extr emacsbug message rfc822 mml easymenu mml-sec

mm-decode mm-bodies mm-encode mail-parse rfc2231 mailabbrev gmm-utils

mailheader sendmail rfc2047 rfc2045 ietf-drums mail-utils tramp-cache

tramp-sh tramp tramp-compat auth-source eieio byte-opt bytecomp

byte-compile cconv gnus-util mm-util mail-prsvr password-cache

tramp-loaddefs shell pcomplete comint ansi-color ring format-spec advice

help-fns cl-lib advice-preload time-date tooltip ediff-hook vc-hooks

lisp-float-type mwheel ns-win tool-bar dnd fontset image regexp-opt

fringe tabulated-list newcomment lisp-mode register page menu-bar

rfn-eshadow timer select scroll-bar mouse jit-lock font-lock syntax

facemenu font-core frame cham georgian utf-8-lang misc-lang vietnamese

tibetan thai tai-viet lao korean japanese hebrew greek romanian slovak

czech european ethiopic indian cyrillic chinese case-table epa-hook

jka-cmpr-hook help simple abbrev minibuffer loaddefs button faces

cus-face macroexp files text-properties overlay sha1 md5 base64 format

env code-pages mule custom widget hashtable-print-readable backquote

make-network-process ns multi-tty emacs)

[-- Attachment #1.2: Type: text/html, Size: 10412 bytes --]

[-- Attachment #2: fix-tramp-dollar-filename.patch --]
[-- Type: application/octet-stream, Size: 471 bytes --]

diff --git a/lisp/net/tramp-sh.el b/lisp/net/tramp-sh.el
index 22ea771..ca1af88 100644
--- a/lisp/net/tramp-sh.el
+++ b/lisp/net/tramp-sh.el
@@ -954,7 +954,7 @@ target of the symlink differ."
 	    (setq result
 		  (tramp-send-command-and-read
 		   v
-		   (format "echo \"\\\"`%s --canonicalize-missing %s`\\\"\""
+		   (format "echo \"\\\"$(%s --canonicalize-missing %s)\\\"\""
 			   (tramp-get-remote-readlink v)
 			   (tramp-shell-quote-argument localname)))))
 

bug#17238: 24.3; TRAMP Can't open remote file with '$' in the filename

[Michael Albinus]

Dana Pieluszczak <danajp@gmail.com> writes:

Hi Dana,

> # now we're in emacs
> C-x C-f DEL DEL /dana@192.168.1.105:/home/dana/t$test.txt RET

For the records, it should be "/dana@192.168.1.105:/home/dana/t$$test.txt".
It works for you because "$test" is not an environment variable;
otherwise it would be replaced.

> Actual result
>
> - a new buffer called t$test.txt is opened
> - the buffer is empty
> - The following is written to *Messages* buffer:
> File exists, but cannot be read

Confirmed, I could reproduce it.

> This is a bug in tramp-sh-handle-file-truename. I've attached a
> patch. The current version of tramp-sh-handle-file-truename uses
> backticks inside a quoted string. Shell arguments used inside the
> backticks should be shell escaped twice, but they're not.
>
> I've changed the shell command to use a subshell ( $(...) )
> Instead of backticks which removes the need for the double escaping.

We cannot use the $(...) syntax, because we don't know whether the
remote shell does support it. Instead, we shall quote the file name twice.

Does the following patch work for you? (The line numbers might differ)

--8<---------------cut here---------------start------------->8---
*** /usr/share/emacs/24.3/lisp/net/tramp-sh.el.~1~	2014-04-11 08:19:48.434437606 +0200
--- /usr/share/emacs/24.3/lisp/net/tramp-sh.el	2014-04-11 08:19:48.594440377 +0200
***************
*** 1066,1072 ****
  		   v
  		   (format "echo \"\\\"`%s --canonicalize-missing %s`\\\"\""
  			   (tramp-get-remote-readlink v)
! 			   (tramp-shell-quote-argument localname)))))

  	   ;; Use Perl implementation.
  	   ((and (tramp-get-remote-perl v)
--- 1066,1073 ----
  		   v
  		   (format "echo \"\\\"`%s --canonicalize-missing %s`\\\"\""
  			   (tramp-get-remote-readlink v)
! 			   (tramp-shell-quote-argument
! 			    (tramp-shell-quote-argument localname))))))

  	   ;; Use Perl implementation.
  	   ((and (tramp-get-remote-perl v)
--8<---------------cut here---------------end--------------->8---

> Dana P

Best regards, Michael.

bug#17238: 24.3; TRAMP Can't open remote file with '$' in the filename

[Dana Pieluszczak]

Michael,

> We cannot use the $(...) syntax, because we don't know whether the
> remote shell does support it. Instead, we shall quote the file name twice.

I figured that might be the reason for the backticks.

> Does the following patch work for you? (The line numbers might differ)

Yes, works for me.

Thanks,

Dana P

bug#17238: 24.3; TRAMP Can't open remote file with '$' in the filename

[Michael Albinus]

Version: 24.4

Dana Pieluszczak <danajp@gmail.com> writes:

> Michael,

Hi Dana,

>> Does the following patch work for you? (The line numbers might differ)
>
> Yes, works for me.

Thanks for confirmation. I've committed the patch in the emacs-24
branch, it will appear with Emacs 24.4. Closing the bug.

> Thanks,
>
> Dana P

Best regards, Michael.