1 ;;; dirtrack.el --- Directory Tracking by watching the prompt
3 ;; Copyright (C) 1996 Free Software Foundation, Inc.
5 ;; Author: Peter Breton <pbreton@cs.umb.edu>
6 ;; Created: Sun Nov 17 1996
8 ;; Time-stamp: <1998-03-14 09:24:38 pbreton>
10 ;; This file is part of GNU Emacs.
12 ;; GNU Emacs is free software; you can redistribute it and/or modify
13 ;; it under the terms of the GNU General Public License as published by
14 ;; the Free Software Foundation; either version 2, or (at your option)
17 ;; GNU Emacs is distributed in the hope that it will be useful,
18 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
19 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 ;; GNU General Public License for more details.
22 ;; You should have received a copy of the GNU General Public License
23 ;; along with GNU Emacs; see the file COPYING. If not, write to the
24 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
25 ;; Boston, MA 02111-1307, USA.
29 ;; Shell directory tracking by watching the prompt.
31 ;; This is yet another attempt at a directory-tracking package for
32 ;; Emacs shell-mode. However, this package makes one strong assumption:
33 ;; that you can customize your shell's prompt to contain the
34 ;; current working directory. Most shells do support this, including
35 ;; almost every type of Bourne and C shell on Unix, the native shells on
36 ;; Windows95 (COMMAND.COM) and Windows NT (CMD.EXE), and most 3rd party
37 ;; Windows shells. If you cannot do this, or do not wish to, this package
38 ;; will be useless to you.
42 ;; 1) Set your shell's prompt to contain the current working directory.
43 ;; You may need to consult your shell's documentation to find out how to
46 ;; Note that directory tracking is done by matching regular expressions,
47 ;; therefore it is *VERY IMPORTANT* for your prompt to be easily
48 ;; distinguishable from other output. If your prompt regexp is too general,
49 ;; you will see error messages from the dirtrack filter as it attempts to cd
50 ;; to non-existent directories.
52 ;; 2) Set the variable `dirtrack-list' to an appropriate value. This
53 ;; should be a list of two elements: the first is a regular expression
54 ;; which matches your prompt up to and including the pathname part.
55 ;; The second is a number which tells which regular expression group to
56 ;; match to extract only the pathname. If you use a multi-line prompt,
57 ;; add 't' as a third element. Note that some of the functions in
58 ;; 'comint.el' assume a single-line prompt (eg, comint-bol).
60 ;; Determining this information may take some experimentation. Setting
61 ;; the variable `dirtrack-debug' may help; it causes the directory-tracking
62 ;; filter to log messages to the buffer `dirtrack-debug-buffer'.
64 ;; 3) Add a hook to shell-mode to enable the directory tracking:
66 ;; (add-hook 'shell-mode-hook
67 ;; (function (lambda ()
68 ;; (setq comint-output-filter-functions
69 ;; (append (list 'dirtrack)
70 ;; comint-output-filter-functions)))))
72 ;; You may wish to turn ordinary shell tracking off by calling
73 ;; `shell-dirtrack-toggle' or setting `shell-dirtrackp'.
77 ;; 1) On Windows NT, my prompt is set to emacs$S$P$G.
78 ;; 'dirtrack-list' is set to (list "^emacs \\([a-zA-Z]:.*\\)>" 1)
80 ;; 2) On Solaris running bash, my prompt is set like this:
81 ;; PS1="\w\012emacs@\h(\!) [\t]% "
82 ;; 'dirtrack-list' is set to (list "^\\([/~].*\\)\nemacs@[^%]+% *" 1 t)
84 ;; I'd appreciate other examples from people who use this package.
86 ;; Here's one from Stephen Eglen:
88 ;; Running under tcsh:
89 ;; (setq-default dirtrack-list '("^%E \\([^ ]+\\)" 1))
91 ;; It might be worth mentioning in your file that emacs sources start up
92 ;; files of the form: ~/.emacs_<SHELL> where <SHELL> is the name of the
93 ;; shell. So for example, I have the following in ~/.emacs_tcsh:
95 ;; set prompt = "%%E %~ %h% "
97 ;; This produces a prompt of the form:
100 ;; This saves me from having to use the %E prefix in other non-emacs
109 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
110 ;; Customization Variables
111 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
113 (defgroup dirtrack nil
114 "Directory tracking by watching the prompt."
118 (defcustom dirtrack-list (list "^emacs \\([a-zA-Z]:.*\\)>" 1)
119 "*List for directory tracking.
120 First item is a regexp that describes where to find the path in a prompt.
121 Second is a number, the regexp group to match. Optional third item is
122 whether the prompt is multi-line. If nil or omitted, prompt is assumed to
123 be on a single line."
125 :type '(sexp (regexp :tag "Prompt Expression")
126 (integer :tag "Regexp Group")
127 (boolean :tag "Multiline Prompt")
131 (make-variable-buffer-local 'dirtrack-list)
133 (defcustom dirtrack-debug nil
134 "*If non-nil, the function `dirtrack' will report debugging info."
139 (defcustom dirtrack-debug-buffer "*Directory Tracking Log*"
140 "Buffer to write directory tracking debug information."
145 (defcustom dirtrackp t
146 "*If non-nil, directory tracking via `dirtrack' is enabled."
151 (make-variable-buffer-local 'dirtrackp)
153 (defcustom dirtrack-directory-function
154 (if (memq system-type (list 'ms-dos 'windows-nt))
155 'dirtrack-windows-directory-function
156 'dirtrack-default-directory-function)
157 "*Function to apply to the prompt directory for comparison purposes."
162 (defcustom dirtrack-canonicalize-function
163 (if (memq system-type (list 'ms-dos 'windows-nt))
165 "*Function to apply to the default directory for comparison purposes."
170 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
172 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
174 (defun dirtrack-default-directory-function (dir)
175 "Return a canonical directory for comparison purposes.
176 Such a directory ends with a forward slash."
177 (let ((directory dir))
178 (if (not (char-equal ?/ (string-to-char (substring directory -1))))
179 (concat directory "/")
182 (defun dirtrack-windows-directory-function (dir)
183 "Return a canonical directory for comparison purposes.
184 Such a directory is all lowercase, has forward-slashes as delimiters,
185 and ends with a forward slash."
186 (let ((directory dir))
187 (setq directory (downcase (dirtrack-replace-slash directory t)))
188 (if (not (char-equal ?/ (string-to-char (substring directory -1))))
189 (concat directory "/")
192 (defconst dirtrack-forward-slash (regexp-quote "/"))
193 (defconst dirtrack-backward-slash (regexp-quote "\\"))
195 (defun dirtrack-replace-slash (string &optional opposite)
196 "Replace forward slashes with backwards ones.
197 If additional argument is non-nil, replace backwards slashes with
199 (let ((orig (if opposite
200 dirtrack-backward-slash
201 dirtrack-forward-slash))
202 (replace (if opposite
203 dirtrack-forward-slash
204 dirtrack-backward-slash))
207 (while (string-match orig newstring)
208 (setq newstring (replace-match replace nil t newstring)))
211 ;; Copied from shell.el
212 (defun dirtrack-toggle ()
213 "Enable or disable Dirtrack directory tracking in a shell buffer."
215 (setq dirtrackp (not dirtrackp))
216 (message "Directory tracking %s" (if dirtrackp "ON" "OFF")))
218 (defun dirtrack-debug-message (string)
219 (let ((buf (current-buffer))
220 (debug-buf (get-buffer-create dirtrack-debug-buffer))
222 (set-buffer debug-buf)
223 (goto-char (point-max))
224 (insert (concat string "\n"))
229 (defun dirtrack (input)
233 (current-dir default-directory)
235 (dirtrack-regexp (nth 0 dirtrack-list))
236 (match-num (nth 1 dirtrack-list))
237 (multi-line (nth 2 dirtrack-list))
240 (if (eq (point) (point-min))
243 (goto-char (point-max))
244 ;; Look for the prompt
249 comint-last-output-start
252 (setq matched (looking-at dirtrack-regexp)))
256 (dirtrack-debug-message
258 "Failed to match regexp: %s"
261 (buffer-substring-no-properties
262 (match-beginning match-num) (match-end match-num)))
264 (if (not (> (length prompt-path) 0))
266 (dirtrack-debug-message "Match is empty string"))
267 ;; Transform prompts into canonical forms
268 (setq prompt-path (funcall dirtrack-directory-function
270 (setq current-dir (funcall dirtrack-canonicalize-function
273 (dirtrack-debug-message
275 "Prompt is %s\nCurrent directory is %s"
276 prompt-path current-dir)))
278 (if (or (string= current-dir prompt-path)
280 (abbreviate-file-name prompt-path)))
282 (dirtrack-debug-message
283 (format "Not changing directory")))
284 ;; It's possible that Emacs will think the directory
285 ;; won't exist (eg, rlogin buffers)
286 (if (file-accessible-directory-p prompt-path)
288 (and (shell-process-cd prompt-path)
290 (dirtrack-debug-message
291 (format "Changing directory to %s" prompt-path)))
292 (error "Directory %s does not exist" prompt-path)))
297 ;;; dirtrack.el ends here