bug#18943: 24.4; Cannot jump to bookmark with tramp-via-proxy

[Moritz Bunkus <moritz@bunkus.org>]

I'm using tramp with sshx & sudo for logging into remote machines as a
normal user and editing root-owned files there. I have some files that I
visit often, so I set a bookmark to these files. When I jump to such a
bookmark I receive the following error message:

--------------------------------------------------
Tramp: Opening connection for root@spector using sudo...failed
byte-code: Host `spector' looks like a remote host, `sudo' can only use the local host
--------------------------------------------------

How to reproduce:

1. Run `emacs -Q`

2. Connect to a remote host via a proxy,
e.g. "/sshx:mbunkus@spector|sudo:root@spector:/var/cache/bind/domain.db"

3. Set a bookmark with M-x bookmark-set

4. Save the bookmarks with M-x bookmark-save

Here's how such a bookmark looks like:

("domain.db"
 (filename . "/sshx:mbunkus@spector|sudo:root@spector:/var/cache/bind/linet/domain.db")
 (front-context-string . "; -*- mode: zone")
 (rear-context-string)
 (position . 1))

5. Exit and restart Emacs with `emacs -Q`

6. Jump to the bookmark set in 3.; now the error message occurs.

What's interesting is that I circumvent that error by manually opening a
similar tramp-sudo-via-sshx-proxy connection to any file on the same
host (e.g. to
"/sshx:mbunkus@spector|sudo:root@spector:/root/.bashrc"). After I've
done that once jumping to the bookmark miraculously starts working (no
further errors, the files are opened just as I expect them to
be). However, bookmarks to other hosts do not start working after such a
workaround.

In GNU Emacs 24.4.1 (x86_64-unknown-linux-gnu, GTK+ Version 3.14.3)
 of 2014-10-21 on bitzer.hoetzel.info
Windowing system distributor `The X.Org Foundation', version 11.0.11601000
Configured using:
 `configure --prefix=/usr --sysconfdir=/etc --libexecdir=/usr/lib
 --localstatedir=/var --with-x-toolkit=gtk3 --with-xft
 'CFLAGS=-march=x86-64 -mtune=generic -O2 -pipe -fstack-protector-strong
 --param=ssp-buffer-size=4' CPPFLAGS=-D_FORTIFY_SOURCE=2
 LDFLAGS=-Wl,-O1,--sort-common,--as-needed,-z,relro'

Important settings:
  value of $LC_COLLATE: de_DE.UTF-8
  value of $LC_CTYPE: de_DE.UTF-8
  value of $LC_MONETARY: de_DE.UTF-8
  value of $LC_NUMERIC: de_DE.UTF-8
  value of $LC_TIME: de_DE.UTF-8
  value of $LANG: en_US.UTF-8
  locale-coding-system: utf-8-unix

Major mode: Messages

Minor modes in effect:
  magit-auto-revert-mode: t
  ido-everywhere: t
  shell-dirtrack-mode: t
  diff-auto-refine-mode: t
  global-edit-server-edit-mode: t
  which-function-mode: t
  global-hl-line-mode: t
  show-paren-mode: t
  winner-mode: t
  yas-global-mode: t
  yas-minor-mode: t
  tooltip-mode: t
  mouse-wheel-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
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
C-x r b <return> C-x C-f / s s h x : m b u n k u s
<return> / C-g C-x r b <up> <return> C-x b m e s <return>
M-x r e p o r t <return>

Recent messages:
Tramp: Sending command `exec ssh   -o ControlPath=/tmp/tramp.151851xI.%r@%h:%p -o ControlMaster=auto -o ControlPersist=no -e none -t -t mirax.bunkus.org /bin/sh'
Tramp: Waiting for prompts from remote shell...
Tramp failed to connect.  If this happens repeatedly, try
    `M-x tramp-cleanup-this-connection'
Tramp: Waiting for prompts from remote shell...failed
Tramp: Opening connection for mirax.bunkus.org using sshx...failed
Error in post-command-hook (ido-exhibit): (file-error "Tramp failed to connect.  If this happens repeatedly, try
    `M-x tramp-cleanup-this-connection'")
Quit
Tramp: Opening connection for root@spector using sudo...failed
byte-code: Host `spector' looks like a remote host, `sudo' can only use the local host

Load-path shadows:
/home/mbunkus/.emacs.d/site-start.d/libs/paredit hides /home/mbunkus/.emacs.d/elpa/paredit-20140128.1248/paredit
/home/mbunkus/.emacs.d/site-start.d/libs/apache-mode hides /usr/share/emacs/site-lisp/apache-mode
/home/mbunkus/.emacs.d/elpa/markdown-mode-20140819.602/markdown-mode hides /usr/share/emacs/site-lisp/markdown-mode/markdown-mode
/home/mbunkus/.emacs.d/site-start.d/libs/buff-menu hides /usr/share/emacs/24.4/lisp/buff-menu
/home/mbunkus/.emacs.d/site-start.d/libs/cc-langs hides /usr/share/emacs/24.4/lisp/progmodes/cc-langs
/home/mbunkus/.emacs.d/site-start.d/libs/cc-align hides /usr/share/emacs/24.4/lisp/progmodes/cc-align
/home/mbunkus/.emacs.d/site-start.d/libs/cc-defs hides /usr/share/emacs/24.4/lisp/progmodes/cc-defs
/home/mbunkus/.emacs.d/site-start.d/libs/cc-mode hides /usr/share/emacs/24.4/lisp/progmodes/cc-mode
/home/mbunkus/.emacs.d/site-start.d/libs/cc-fonts hides /usr/share/emacs/24.4/lisp/progmodes/cc-fonts
/home/mbunkus/.emacs.d/site-start.d/libs/cc-styles hides /usr/share/emacs/24.4/lisp/progmodes/cc-styles
/home/mbunkus/.emacs.d/site-start.d/libs/cc-vars hides /usr/share/emacs/24.4/lisp/progmodes/cc-vars
/home/mbunkus/.emacs.d/site-start.d/libs/cc-menus hides /usr/share/emacs/24.4/lisp/progmodes/cc-menus
/home/mbunkus/.emacs.d/site-start.d/libs/cc-cmds hides /usr/share/emacs/24.4/lisp/progmodes/cc-cmds
/home/mbunkus/.emacs.d/site-start.d/libs/cc-awk hides /usr/share/emacs/24.4/lisp/progmodes/cc-awk
/home/mbunkus/.emacs.d/elpa/flymake-0.4.16/flymake hides /usr/share/emacs/24.4/lisp/progmodes/flymake
/home/mbunkus/.emacs.d/site-start.d/libs/cc-compat hides /usr/share/emacs/24.4/lisp/progmodes/cc-compat
/home/mbunkus/.emacs.d/site-start.d/libs/cc-engine hides /usr/share/emacs/24.4/lisp/progmodes/cc-engine
/home/mbunkus/.emacs.d/site-start.d/libs/cfengine hides /usr/share/emacs/24.4/lisp/progmodes/cfengine
/home/mbunkus/.emacs.d/site-start.d/libs/cperl-mode/cperl-mode hides /usr/share/emacs/24.4/lisp/progmodes/cperl-mode
/home/mbunkus/.emacs.d/site-start.d/libs/cc-bytecomp hides /usr/share/emacs/24.4/lisp/progmodes/cc-bytecomp
/home/mbunkus/.emacs.d/site-start.d/libs/cc-guess hides /usr/share/emacs/24.4/lisp/progmodes/cc-guess
/home/mbunkus/.emacs.d/site-start.d/libs/cl-lib hides /usr/share/emacs/24.4/lisp/emacs-lisp/cl-lib

Features:
(shadow sort mail-extr emacsbug tramp-cache tramp-sh vc-git bookmark pp
f s paredit two-column 70-perl cperl-mode 70-ido magit-blame
dired-sort-map dired-single magit-key-mode magit iswitchb ido esh-var
esh-io esh-cmd esh-opt esh-ext esh-proc esh-arg eldoc esh-groups eshell
esh-module esh-mode esh-util ediff-merg ediff-wind ediff-diff ediff-mult
ediff-help ediff-init ediff-util ediff dired-x dired view tramp
tramp-compat auth-source gnus-util password-cache tramp-loaddefs
trampver shell pcomplete grep compile comint epa epg diff-mode
autorevert filenotify ansi-color git-rebase-mode thingatpt
git-commit-mode server log-edit message idna sendmail format-spec rfc822
mml mml-sec mm-decode mm-bodies mm-encode mail-parse rfc2231 rfc2047
rfc2045 ietf-drums mm-util mail-prsvr mailabbrev mail-utils gmm-utils
mailheader pcvs-util add-log solarized-light-theme solarized-definitions
70-html-xml rng-nxml rng-valid rng-loc rng-uri rng-parse nxml-parse
rng-match rng-dt rng-util rng-pttrn nxml-ns nxml-mode nxml-outln
nxml-rap nxml-util nxml-glyph nxml-enc xmltok saveplace buff-menu+
buff-menu edit-server 70-helpers which-func imenu dash-functional dash
browse-kill-ring hl-line paren 70-text 70-tabs filladapt winner ring
01-version-test my-site-start yasnippet advice help-fns derived
easy-mmode edmacro kmacro help-mode ack-and-a-half-autoloads
ag-autoloads clojure-test-mode-autoloads cider-autoloads
dash-functional-autoloads elixir-mode-autoloads expand-region-autoloads
f-autoloads dash-autoloads flymake-autoloads flymake-yaml-autoloads
flymake-easy-autoloads gist-autoloads finder-inf gh-autoloads eieio
byte-opt bytecomp byte-compile cconv eieio-core logito-autoloads info
easymenu magit-autoloads git-rebase-mode-autoloads
git-commit-mode-autoloads markdown-mode-autoloads nrepl-autoloads
clojure-mode-autoloads paredit-autoloads pcache-autoloads
pkg-info-autoloads epl-autoloads s-autoloads tracwiki-mode-autoloads
xml-rpc-autoloads yaml-mode-autoloads package epg-config cl-macs cl gv
cl-loaddefs cl-lib time-date tooltip electric uniquify ediff-hook
vc-hooks lisp-float-type mwheel x-win x-dnd tool-bar dnd fontset image
regexp-opt fringe tabulated-list newcomment lisp-mode prog-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 nadvice
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 dbusbind
gfilenotify dynamic-setting system-font-setting font-render-setting
move-toolbar gtk x-toolkit x multi-tty emacs)

Memory information:
((conses 16 386179 23509)
 (symbols 48 36382 18)
 (miscs 40 138 115)
 (strings 32 81254 21635)
 (string-bytes 1 2245590)
 (vectors 16 28782)
 (vector-slots 8 606647 1907)
 (floats 8 249 121)
 (intervals 56 323 1)
 (buffers 960 15)
 (heap 1024 56800 2345))