-;;; multishell.el --- facilitate use of multiple local and remote shell buffers
+;;; multishell.el --- facilitate multiple local and remote shell buffers
;; Copyright (C) 1999-2016 Free Software Foundation, Inc. and Ken Manheimer
;; Author: Ken Manheimer <ken.manheimer@gmail.com>
-;; Version: 1.0.5
+;; Version: 1.0.8
;; Created: 1999 -- first public availability
;; Keywords: processes
;; URL: https://github.com/kenmanheimer/EmacsMultishell
;; a la `pop-to-buffer' - plus a keybinding. Together, they enable you to:
;;
;; * Get to the input point from wherever you are in a shell buffer,
-;; * ... or to one of your shell buffers if you're not currently in one.
+;; ... or to any of your shell buffers, from anywhere inside emacs.
+;;
;; * Use universal arguments to launch and choose among alternate shell buffers,
-;; * ... and select which is default.
+;; ... and change which is the current default.
+;;
+;; * Easily restart disconnected shells, or shells from prior sessions
+;; ... the latter from Emacs builtin savehist minibuf history persistence
+;;
;; * Append a path to a new shell name to launch a shell in that directory,
-;; * ... and use a path with Emacs tramp syntax to launch a remote shell.
+;; ... and use a path with Emacs tramp syntax to launch a remote shell -
+;; for example:
;;
-;; For example:
+;; * `#root/sudo:root@localhost:/etc` for a buffer named "#root" with a
+;; root shell starting in /etc.
;;
-;; * `/ssh:example.net:/` for a shell buffer in / on
-;; example.net; the buffer will be named "*example.net*".
+;; * `/ssh:example.net:/` for a shell buffer in / on example.net.
+;; The buffer will be named "*example.net*".
;;
;; * `#ex/ssh:example.net|sudo:root@example.net:/etc` for a root shell
;; starting in /etc on example.net named "*#ex*".
;;
-;; (NOTE - there's a sporadic problem when opening a shell pointed at a
-;; remote homedir, eg `/ssh:example.net:` or `/ssh:example.net:~`. It
-;; sometimes fails, particularly for remotes with empty fs path syntax. Until
-;; fixed, you may need to start remote shells with an explicit path, then
-;; cd ~. If you set up `multishell`s persistent dir-tracking history,
-;; you'll be able to use completion to start that shell in the right place,
-;; in your subsequent sessions.)
+;; * 'interior/ssh:gateway.corp.com|ssh:interior.corp.com:' to go via
+;; gateway.corp.com to your homedir on interior.corp.com. The buffer
+;; will be named "*interior*". You could append a sudo hop, and so on.
;;
+;; * Thanks to tramp, file visits from the shell will seamlessly be in
+;; the auspices of the target account, and relative to the current
+;; directory, on the host where the shell is running.
+;;
;; See the `multishell-pop-to-shell` docstring for details.
;;
;; Customize-group `multishell' to select and activate a keybinding and set
;; various behaviors. Customize-group `savehist' to preserve buffer
-;; names/paths across emacs sessions.
+;; names/paths across emacs restarts.
;;
-;; See the `multishell-pop-to-shell' docstring for details.
-;;
-;; Please use [the repository](https://github.com/kenmanheimer/EmacsMultishell)
-;; issue tracker to report problems, suggestions, etc.
+;; Please use
+;; [the multishell repository](https://github.com/kenmanheimer/EmacsMultishell)
+;; issue tracker to report problems, suggestions, etc, and see that
+;; repository for a bit more documentation.
;;
;; Change Log:
;;
+;; * 2016-01-24 1.0.8 Ken Manheimer:
+;; - Work around the shell/tramp mishandling of remote+sudo+homedir problem!
+;; The work around is clean and simple, basically using high-level `cd'
+;; API and not messing with the low-level default-directory setting.
+;; (Turns out the problem was not in my local config. Good riddance to the
+;; awkward failure handler!)
+;; - Clean up code resolving the destination shell, starting to document the
+;; decision tree in the process. See getting-to-a-shell.md in the
+;; multishell repository, https://github.com/kenmanheimer/EmacsMultishell
+;; - There may be some shake-out on resolving the destination shell, but
+;; this release gets the fundamental functionality soundly in place.
+;; * 2016-01-23 1.0.7 Ken Manheimer:
+;; - Remove notes about tramp remote+sudo+homedir problem. Apparently it's
+;; due to something in my local site configuration (happens with -q but
+;; not -Q).
+;; * 2016-01-22 1.0.6 Ken Manheimer:
+;; - Add multishell-version function.
+;; - Tweak commentary/comments/docstrings.
+;; - Null old multishell-buffer-name-history var, if present.
;; * 2016-01-16 1.0.5 Ken Manheimer:
-;; - History now includes paths, when designated
+;; - History now includes paths, when designated.
;; - Actively track current directory in history entries that have a path.
;; Custom control: multishell-history-entry-tracks-current-directory
;; - Offer to remove shell's history entry when buffer is killed.
;; (Currently the only UI mechanism to remove history entries.)
;; - Fix - prevent duplicate entries for same name but different paths
;; - Fix - recognize and respect tramp path syntax to start in home dir
-;; - But tramp bug, remote w/empty path (homedir) often fails, gets wedged.
;; - Simplify history var name, migrate existing history if any from old name
;; * 2016-01-04 1.0.4 Ken Manheimer - Released to ELPA
;; * 2016-01-02 Ken Manheimer - working on this in public, but not yet released.
;;
;; TODO:
;;
-;; * Isolate tramp sporadic failure to connect to remote+homedir (empty path)
-;; syntax
-;; (eg, /ssh:xyz.com|sudo:root@xyz.com: or /ssh:xyz.com|sudo:root@xyz.com:~)
-;; * Find suitable, internally consistent ways to sort tidy completions, eg:
+;; * Find suitable, internally consistent ways to tidy completions, eg:
;; - first list completions for active shells, then present but inactive,
;; then historical
;; - some way for user to toggle between presenting just buffer names vs
;; full buffer/path
;; - without cutting user off from easy editing of path
-;; * Find proper method for setting field boundary at beginning of tramp path
-;; in the minibuffer, in order to see whether the field boundary magically
-;; enables tramp completion of the path.
-;; * Assess whether option to delete history entry on kill-buffer is
-;; sufficient.
+;; * Try minibuffer field boundary at beginning of tramp path, to see whether
+;; the field boundary magically enables tramp path completion.
+;; * Assess whether deletion of history entry via kill-buffer is sufficient.
;;; Code:
(require 'comint)
(require 'shell)
+(require 'savehist)
+
+(defvar multishell-version "1.0.8")
+(defun multishell-version (&optional here)
+ "Return string describing the loaded multishell version."
+ (interactive "P")
+ (let ((msg (concat "Multishell " multishell-version)))
+ (if here (insert msg)
+ (if (called-interactively-p 'interactive)
+ (message "%s" msg)
+ msg))))
(defgroup multishell nil
"Allout extension that highlights outline structure graphically.
:set 'multishell-activate-command-key-setter
:group 'multishell)
-;; Assert the customizations whenever the package is loaded:
+;; Implement the key customization whenever the package is loaded:
(with-eval-after-load "multishell"
(multishell-implement-command-key-choice))
(defcustom multishell-pop-to-frame nil
- "*If non-nil, jump to a frame already showing the shell, if another is.
+ "*If non-nil, jump to a frame already showing the shell, if another one is.
Otherwise, disregard already-open windows on the shell if they're
in another frame, and open a new window on the shell in the
current frame.
-\(Use `pop-up-windows' to change multishell other-buffer vs
-current-buffer behavior.)"
+\(Use `pop-up-windows' to change multishell other-window vs
+current-window behavior.)"
:type 'boolean
:group 'multishell)
(defcustom multishell-history-entry-tracks-current-directory t
- "Modify shell buffer's multishell entry to track the current directory.
+ "Maintain shell's current directory in its multishell history entry.
-When set, the path part of the name/path entry for each shell
-will track the current directory of the shell with emacs. If
-`savehist' is active, the directory tracking will extend across
-emacs sessions."
+When set, the history entry for shells started with explicit
+paths will track the shell's current working directory. (Explicit
+paths will not be added to local shells started without one,
+however.)
+
+If `savehist-save-minibuffer-history' is enabled, the current
+working directory of shells \(that were started with an explicit
+path) will be conveyed between emacs sessions."
:type 'boolean
:group 'multishell)
(defvar multishell-history nil
"Name/path entries, most recent first.")
+;; Migrate the few pre 1.0.5 users to changed history var:
(when (and (not multishell-history)
(boundp 'multishell-buffer-name-history)
multishell-buffer-name-history)
- ;; Migrate few users who had old var to new.
- (setq multishell-history multishell-buffer-name-history)
- )
+ (setq multishell-history multishell-buffer-name-history
+ multishell-buffer-name-history nil))
(defvar multishell-primary-name "*shell*"
- "Shell name to use for un-modified multishell-pop-to-shell buffer target.")
-
-;; There is usually only one entry per name, but disruptions happen.
+ "Default shell name for un-modified multishell-pop-to-shell buffer target.
+
+This is adjusted by `multishell-pop-to-shell' when it is
+invoked (with doubled universal argument) to set the default.
+
+To preserve changes to this setting across emacs restarts, add it
+to `savehist-additional-variables' by customizing the latter.")
+
+;;; Can't just add multishell-primary-name to savehist-additional-variables
+;;; - it'll be lost any time the user runs emacs without loading
+;;; multishell. So instead, inform the user that they can customize
+;;; savehist-additional-variables.
+;;;
+;;; I suspect that including savehist-additional-variables *on*
+;;; savehist-additional-variables could avoid this problem, as long as it
+;;; doesn't conflict with user customizations. However, even if that works,
+;;; doing so from multishell would change a behavior (for the better, but)
+;;; beyond multishell's scope, making the change hard to track down.
+
+;; (when (not (member 'multishell-primary-name
+;; savehist-additional-variables))
+;; (setq savehist-additional-variables
+;; (cons 'multishell-primary-name savehist-additional-variables)))
+
+;; Multiple entries happen because completion also adds name to history.
(defun multishell-register-name-to-path (name path)
"Add or replace entry associating NAME with PATH in `multishell-history'.
-Promote to added/changed entry to the front of the list."
+If NAME already had a PATH and new PATH is empty, retain the prior one.
+
+Promote added/changed entry to the front of the list."
;; Add or promote to the front, tracking path changes in the process.
(let* ((entries (multishell-history-entries name))
- (becomes (concat name path)))
+ (path (or path "")))
(dolist (entry entries)
+ (when (string= path "")
+ ;; Retain explicit established path.
+ (setq path (cadr (multishell-split-entry entry))))
(setq multishell-history (delete entry multishell-history)))
- (setq multishell-history (push becomes multishell-history))))
+ (setq multishell-history (push (concat name path)
+ multishell-history))))
(defun multishell-history-entries (name)
"Return `multishell-history' entry that starts with NAME, or nil if none."
- (let ((match-expr (concat "^" name "\\\(/.*$\\\)?"))
+ (let ((match-expr (concat "^" name "\\\(/.*$\\\)?$"))
got)
(dolist (entry multishell-history)
(when (and (string-match match-expr entry)
Completion is available.
- This combination makes it easy to start and switch between
- multiple shell buffers.
+ This combination makes it easy to start and switch across
+ multiple shell restarts.
- A double universal argument will prompt for the name *and* set
the default to that name, so the target shell becomes the
primary.
+ See `multishell-primary-name' for info about preserving the
+ setting across emacs restarts.
+
===== Select starting directory and remote host:
The shell buffer name you give to the prompt for a universal arg
For example:
-* Use '/ssh:example.net:/home/myaccount' for a shell buffer in
- /home/myaccount on example.net; the buffer will be named
- \"*example.net*\".
-* '\#ex/ssh:example.net|sudo:root@example.net:/etc' for a root
- shell in /etc on example.net named \"*#ex*\".
+* '#root/sudo:root@localhost:/etc' for a buffer named \"#root\" with a
+ root shell starting in /etc.
+
+* '/ssh:example.net:/' for a shell buffer in / on example.net; the buffer
+ will be named \"*example.net*\".
+
+* '#ex/ssh:example.net|sudo:root@example.net:/etc' for a root shell
+ starting in /etc on example.net named \"*#ex*\".
-\(NOTE that there is a problem with specifying a remote homedir using
-tramp syntax, eg '/ssh:example.net:'. That sometimes fails on an obscure
-bug - particularly for remote with empty path (homedir) syntax. Until fixed,
-you may need to start remote shells with an explicit path, then cd ~.)
+* 'interior/ssh:gateway.corp.com|ssh:interior.corp.com:' to go
+ via gateway.corp.com to your homedir on interior.corp.com. The
+ buffer will be named \"*interior*\". You could append a sudo
+ hop to the path, combining the previous example, and so on.
+
+Thanks to tramp, file visits from the shell, and many common
+emacs activities, like dired, will seamlessly be in the auspices
+of the target account, and relative to the current directory, on
+the host where the shell is running.
You can change the startup path for a shell buffer by editing it
at the completion prompt. The new path will be preserved in
To remove a shell buffer's history entry, kill the buffer and
affirm removal of the entry when prompted.
-===== Activate savehist to persisting your shell buffer names and paths:
+===== Activate savehist to retain shell buffer names and paths across Emacs restarts:
-To have emacs maintain your history of shell buffer names and paths,
+To have emacs maintain your history of shell buffer names and paths,
customize the savehist group to activate savehist."
(interactive "P")
(let* ((from-buffer (current-buffer))
(from-buffer-is-shell (derived-mode-p 'shell-mode))
+ (primary-name-unbracketed (multishell-unbracket-asterisks
+ multishell-primary-name))
+ (fallthrough-name (if from-buffer-is-shell
+ (buffer-name from-buffer)
+ primary-name-unbracketed))
(doublearg (equal arg '(16)))
(target-name-and-path
- (multishell-derive-target-name-and-path
+ (multishell-resolve-target-name-and-path
(if arg
- (multishell-read-bare-shell-buffer-name
- (format "Shell buffer name [%s]%s "
- (substring-no-properties
- multishell-primary-name
- 1 (- (length multishell-primary-name) 1))
- (if doublearg " <==" ":"))
- multishell-primary-name)
- multishell-primary-name)))
- (use-default-dir (cadr target-name-and-path))
+ (or (multishell-read-bare-shell-buffer-name
+ (format "Shell buffer name [%s]%s "
+ primary-name-unbracketed
+ (if doublearg " <==" ":"))
+ primary-name-unbracketed)
+ primary-name-unbracketed)
+ fallthrough-name)))
+ (use-path (cadr target-name-and-path))
(target-shell-buffer-name (car target-name-and-path))
+ (target-buffer (get-buffer target-shell-buffer-name))
(curr-buff-proc (get-buffer-process from-buffer))
- (target-buffer (if from-buffer-is-shell
- from-buffer
- (let ((got (get-buffer target-shell-buffer-name)))
- (if (buffer-live-p got)
- got
- (kill-buffer got)
- (get-buffer target-shell-buffer-name)))))
inwin
already-there)
+ ;; Register early so the entry is pushed to the front:
+ (multishell-register-name-to-path (multishell-unbracket-asterisks
+ target-shell-buffer-name)
+ use-path)
+
(when doublearg
(setq multishell-primary-name target-shell-buffer-name))
(if (not (comint-check-proc (current-buffer)))
(multishell-start-shell-in-buffer (buffer-name (current-buffer))
- use-default-dir))
+ use-path))
;; If the destination buffer has a stopped process, resume it:
(let ((process (get-buffer-process (current-buffer))))
(if (and process (equal 'stop (process-status process)))
(continue-process process)))
- (multishell-register-name-to-path (multishell-unbracket-asterisks
- target-shell-buffer-name)
- use-default-dir)
+
(when (or already-there
(equal (current-buffer) from-buffer))
(goto-char (point-max))
(defun multishell-kill-buffer-query-function ()
"Offer to remove multishell-history entry for buffer."
- ;; Removal choice is crucial, so users can, eg, kill and a runaway shell
- ;; and keep the history entry to easily restart it.
+ ;; Removal choice is crucial, so users can, eg, kill a shell with huge
+ ;; output backlog, while keeping the history entry to easily restart it.
;;
;; We use kill-buffer-query-functions instead of kill-buffer-hook because:
;;
- ;; 1. It enables the user to remove the history without killing the buffer,
- ;; by cancelling the kill-buffer process after affirming history removal.
+ ;; 1. It enables the user to remove the history without actually killing a
+ ;; running buffer, by not confirming the subsequent running-proc query.
;; 2. kill-buffer-hooks often fails to run when killing shell buffers!
- ;; I've failed to resolve that, and like the first reason well enough.
+ ;; It's probably due to failures in other hooks - beyond our control -
+ ;; and anyway, I like the first reason well enough.
;; (Use condition-case to avoid inadvertant disruption of kill-buffer
;; activity. kill-buffer happens behind the scenes a whole lot.)
- (condition-case anyerr
- (let ((entries (and (derived-mode-p 'shell-mode)
+ (condition-case err
+ (dolist (entry (and (derived-mode-p 'shell-mode)
(multishell-history-entries
- (multishell-unbracket-asterisks (buffer-name))))))
- (dolist (entry entries)
+ (multishell-unbracket-asterisks (buffer-name)))))
(when (and entry
(y-or-n-p (format "Remove multishell history entry `%s'? "
entry)))
(setq multishell-history
- (delete entry multishell-history)))))
- (error nil))
+ (delete entry multishell-history))))
+ (error
+ (message "multishell-kill-buffer-query-function error: %s" err)))
t)
(add-hook 'kill-buffer-query-functions 'multishell-kill-buffer-query-function)
nil))
(defun multishell-read-bare-shell-buffer-name (prompt default)
- "PROMPT for shell buffer name, sans asterisks.
+ "PROMPT for shell buffer name, sans asterisks. Indicate DEFAULT in prompt.
-Return the supplied name bracketed with the asterisks, or specified DEFAULT
-on empty input."
+Return the supplied name, if provided, else return nil."
(let* ((candidates
(append
;; Plain shell buffer names appended with names from name/path hist:
;; HIST:
'multishell-history)))
(if (not (string= got ""))
- (multishell-bracket-asterisks got)
- default)))
-
-(defun multishell-derive-target-name-and-path (path-ish)
- "Give tramp-style PATH-ISH, determine target name and default directory.
-
-The name is the part of the string before the initial '/' slash,
-if any. Otherwise, it's either the host-name, domain-name, final
-directory name, or local host name. The path is everything
-besides the string before the initial '/' slash.
-
-Return them as a list (name dir), with dir nil if none given."
- (let (name (path "") dir)
- (cond ((string= path-ish "") (setq dir multishell-primary-name))
- ((string-match "^\\*\\([^/]*\\)\\(/.*\\)\\*" path-ish)
- ;; We have a path, use it
- (let ((overt-name (match-string 1 path-ish)))
- (setq path (match-string 2 path-ish))
- (if (string= overt-name "") (setq overt-name nil))
- (if (string= path "") (setq path nil))
- (setq name
- (multishell-bracket-asterisks
- (or overt-name
- (if (file-remote-p path)
- (let ((vec (tramp-dissect-file-name path)))
- (or (tramp-file-name-host vec)
- (tramp-file-name-domain vec)
- (tramp-file-name-localname vec)
- system-name))
- (multishell-unbracket-asterisks
- multishell-primary-name)))))))
- (t (setq name (multishell-bracket-asterisks path-ish))))
- (list name path)))
+ got
+ nil)))
+
+(defun multishell-resolve-target-name-and-path (path-ish)
+ "Given name/tramp-path PATH-ISH, resolve buffer name and initial directory.
+
+The name is the part of the string up to the first '/' slash, if
+any. Missing pieces are filled in from remote path elements, if
+any, and multishell history. Given a path and no name, either the
+host-name, domain-name, final directory name, or local host name
+is used.
+
+Return them as a list (name path), with name asterisk-bracketed
+and path nil if none resolved."
+ (let* ((splat (multishell-split-entry (or path-ish "")))
+ (name (car splat))
+ (path (cadr splat)))
+ (if path
+ (if (not name)
+ (setq name
+ (if (file-remote-p path)
+ (let ((vec (tramp-dissect-file-name path)))
+ (or (tramp-file-name-host vec)
+ (tramp-file-name-domain vec)
+ (tramp-file-name-localname vec)
+ system-name))
+ multishell-primary-name)))
+ ;; No path - get one from history, if present.
+ (when (not name)
+ (setq name multishell-primary-name))
+ (mapcar #'(lambda (entry)
+ (when (or (not path) (string= path ""))
+ (setq path (cadr (multishell-split-entry entry)))))
+ (multishell-history-entries
+ (multishell-unbracket-asterisks name))))
+ (list (multishell-bracket-asterisks name) path)))
(defun multishell-bracket-asterisks (name)
"Return a copy of name, ensuring it has an asterisk at the beginning and end."
(xargs-name (intern-soft (concat "explicit-" name "-args")))
is-remote)
(set-buffer buffer-name)
- (if (and path (not (string= path "")))
- (setq default-directory path))
- (setq is-remote (file-remote-p default-directory))
+ (setq is-remote (and path (file-remote-p path)))
(when (and is-remote
(derived-mode-p 'shell-mode)
(not (comint-check-proc (current-buffer))))
(tramp-cleanup-connection
(tramp-dissect-file-name default-directory 'noexpand)
'keep-debug 'keep-password))
- ;; (cd default-directory) will connect if remote:
(when is-remote
- (message "Connecting to %s" default-directory))
- (condition-case err
- (cd default-directory)
- (error
- ;; Aargh. Need to isolate this tramp bug.
- (when (and (stringp (cadr err))
- (string-equal (cadr err)
- "Selecting deleted buffer"))
- (signal (car err)
- (list
- (format "%s, %s (\"%s\")"
- "Tramp shell can fail on empty (homedir) path"
- "please try again with an explicit path"
- (cadr err)))))))
+ (message "Connecting to %s" path))
+ (if (and path (not (string= path "")))
+ (cd path))
(setq buffer (set-buffer (apply 'make-comint
(multishell-unbracket-asterisks buffer-name)
prog
"Change multishell history entry to track current directory."
(let* ((entries (multishell-history-entries name)))
(dolist (entry entries)
- (let* ((name-path (multishell-split-entry-name-and-tramp entry))
+ (let* ((name-path (multishell-split-entry entry))
(name (car name-path))
(path (cadr name-path)))
(when path
curdir))
(setq multishell-was-default-directory curdir)))
;; To avoid disruption as a pervasive hook function, swallow all errors:
- (error nil)))
+ (error
+ (message "multishell-post-command-business error: %s" err))))
(add-hook 'post-command-hook 'multishell-post-command-business)
-(defun multishell-split-entry-name-and-tramp (entry)
+(defun multishell-split-entry (entry)
"Given multishell name/path ENTRY, return the separated name and path pair.
Returns nil for empty parts, rather than the empty string."