1 ;;; tramp-cache.el --- file information caching for Tramp
3 ;; Copyright (C) 2000, 2005-2013 Free Software Foundation, Inc.
5 ;; Author: Daniel Pittman <daniel@inanna.danann.net>
6 ;; Michael Albinus <michael.albinus@gmx.de>
7 ;; Keywords: comm, processes
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 3 of the License, or
15 ;; (at your option) any later version.
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. If not, see <http://www.gnu.org/licenses/>.
27 ;; An implementation of information caching for remote files.
29 ;; Each connection, identified by a vector [method user host
30 ;; localname] or by a process, has a unique cache. We distinguish 3
31 ;; kind of caches, depending on the key:
33 ;; - localname is NIL. This are reusable properties. Examples:
34 ;; "remote-shell" identifies the POSIX shell to be called on the
35 ;; remote host, or "perl" is the command to be called on the remote
36 ;; host when starting a Perl script. These properties are saved in
37 ;; the file `tramp-persistency-file-name'.
39 ;; - localname is a string. This are temporary properties, which are
40 ;; related to the file localname is referring to. Examples:
41 ;; "file-exists-p" is t or nile, depending on the file existence, or
42 ;; "file-attributes" caches the result of the function
45 ;; - The key is a process. This are temporary properties related to
46 ;; an open connection. Examples: "scripts" keeps shell script
47 ;; definitions already sent to the remote shell, "last-cmd-time" is
48 ;; the time stamp a command has been sent to the remote process.
53 (autoload 'time-stamp-string
"time-stamp")
58 (defvar tramp-cache-data
(make-hash-table :test
'equal
)
59 "Hash table for remote files properties.")
61 (defcustom tramp-persistency-file-name
64 ((and (fboundp 'locate-user-emacs-file
))
65 (expand-file-name (tramp-compat-funcall 'locate-user-emacs-file
"tramp")))
66 ((and (boundp 'user-emacs-directory
)
67 (stringp (symbol-value 'user-emacs-directory
))
68 (file-directory-p (symbol-value 'user-emacs-directory
)))
69 (expand-file-name "tramp" (symbol-value 'user-emacs-directory
)))
70 ((and (not (featurep 'xemacs
)) (file-directory-p "~/.emacs.d/"))
73 ((and (boundp 'user-init-directory
)
74 (stringp (symbol-value 'user-init-directory
))
75 (file-directory-p (symbol-value 'user-init-directory
)))
76 (expand-file-name "tramp" (symbol-value 'user-init-directory
)))
77 ((and (featurep 'xemacs
) (file-directory-p "~/.xemacs/"))
79 ;; For users without `~/.emacs.d/' or `~/.xemacs/'.
81 "File which keeps connection history for Tramp connections."
85 (defvar tramp-cache-data-changed nil
86 "Whether persistent cache data have been changed.")
89 (defun tramp-get-file-property (vec file property default
)
90 "Get the PROPERTY of FILE from the cache context of VEC.
91 Returns DEFAULT if not set."
93 (setq vec
(copy-sequence vec
))
94 (aset vec
3 (tramp-run-real-handler 'directory-file-name
(list file
)))
95 (let* ((hash (or (gethash vec tramp-cache-data
)
96 (puthash vec
(make-hash-table :test
'equal
)
98 (value (when (hash-table-p hash
) (gethash property hash
))))
100 ;; We take the value only if there is any, and
101 ;; `remote-file-name-inhibit-cache' indicates that it is still
102 ;; valid. Otherwise, DEFAULT is set.
104 (or (null remote-file-name-inhibit-cache
)
105 (and (integerp remote-file-name-inhibit-cache
)
107 (tramp-time-diff (current-time) (car value
))
108 remote-file-name-inhibit-cache
))
109 (and (consp remote-file-name-inhibit-cache
)
111 remote-file-name-inhibit-cache
(car value
)))))
112 (setq value
(cdr value
))
113 (setq value default
))
115 (tramp-message vec
8 "%s %s %s" file property value
)
116 (when (>= tramp-verbose
10)
117 (let* ((var (intern (concat "tramp-cache-get-count-" property
)))
118 (val (or (ignore-errors (symbol-value var
)) 0)))
123 (defun tramp-set-file-property (vec file property value
)
124 "Set the PROPERTY of FILE to VALUE, in the cache context of VEC.
127 (setq vec
(copy-sequence vec
))
128 (aset vec
3 (tramp-run-real-handler 'directory-file-name
(list file
)))
129 (let ((hash (or (gethash vec tramp-cache-data
)
130 (puthash vec
(make-hash-table :test
'equal
)
132 ;; We put the timestamp there.
133 (puthash property
(cons (current-time) value
) hash
)
134 (tramp-message vec
8 "%s %s %s" file property value
)
135 (when (>= tramp-verbose
10)
136 (let* ((var (intern (concat "tramp-cache-set-count-" property
)))
137 (val (or (ignore-errors (symbol-value var
)) 0)))
142 (defun tramp-flush-file-property (vec file
)
143 "Remove all properties of FILE in the cache context of VEC."
144 ;; Remove file property of symlinks.
145 (let ((truename (tramp-get-file-property vec file
"file-truename" nil
)))
146 (when (and (stringp truename
)
147 (not (string-equal file truename
)))
148 (tramp-flush-file-property vec truename
)))
150 (setq vec
(copy-sequence vec
))
151 (aset vec
3 (tramp-run-real-handler 'directory-file-name
(list file
)))
152 (tramp-message vec
8 "%s" file
)
153 (remhash vec tramp-cache-data
))
156 (defun tramp-flush-directory-property (vec directory
)
157 "Remove all properties of DIRECTORY in the cache context of VEC.
158 Remove also properties of all files in subdirectories."
159 (let ((directory (tramp-run-real-handler
160 'directory-file-name
(list directory
))))
161 (tramp-message vec
8 "%s" directory
)
164 (when (and (stringp (tramp-file-name-localname key
))
165 (string-match directory
(tramp-file-name-localname key
)))
166 (remhash key tramp-cache-data
)))
169 ;; Reverting or killing a buffer should also flush file properties.
170 ;; They could have been changed outside Tramp. In eshell, "ls" would
171 ;; not show proper directory contents when a file has been copied or
173 (defun tramp-flush-file-function ()
174 "Flush all Tramp cache properties from `buffer-file-name'."
175 (let ((bfn (if (stringp (buffer-file-name))
178 (when (tramp-tramp-file-p bfn
)
179 (with-parsed-tramp-file-name bfn nil
180 (tramp-flush-file-property v localname
)))))
182 (add-hook 'before-revert-hook
'tramp-flush-file-function
)
183 (add-hook 'eshell-pre-command-hook
'tramp-flush-file-function
)
184 (add-hook 'kill-buffer-hook
'tramp-flush-file-function
)
185 (add-hook 'tramp-cache-unload-hook
187 (remove-hook 'before-revert-hook
188 'tramp-flush-file-function
)
189 (remove-hook 'eshell-pre-command-hook
190 'tramp-flush-file-function
)
191 (remove-hook 'kill-buffer-hook
192 'tramp-flush-file-function
)))
197 (defun tramp-get-connection-property (key property default
)
198 "Get the named PROPERTY for the connection.
199 KEY identifies the connection, it is either a process or a vector.
200 If the value is not set for the connection, returns DEFAULT."
201 ;; Unify key by removing localname from vector. Work with a copy in
202 ;; order to avoid side effects.
204 (setq key
(copy-sequence key
))
206 (let* ((hash (gethash key tramp-cache-data
))
207 (value (if (hash-table-p hash
)
208 (gethash property hash default
)
210 (tramp-message key
7 "%s %s" property value
)
214 (defun tramp-set-connection-property (key property value
)
215 "Set the named PROPERTY of a connection to VALUE.
216 KEY identifies the connection, it is either a process or a vector.
217 PROPERTY is set persistent when KEY is a vector."
218 ;; Unify key by removing localname from vector. Work with a copy in
219 ;; order to avoid side effects.
221 (setq key
(copy-sequence key
))
223 (let ((hash (or (gethash key tramp-cache-data
)
224 (puthash key
(make-hash-table :test
'equal
)
226 (puthash property value hash
)
227 (setq tramp-cache-data-changed t
)
228 (tramp-message key
7 "%s %s" property value
)
232 (defun tramp-flush-connection-property (key)
233 "Remove all properties identified by KEY.
234 KEY identifies the connection, it is either a process or a vector."
235 ;; Unify key by removing localname from vector. Work with a copy in
236 ;; order to avoid side effects.
238 (setq key
(copy-sequence key
))
242 (let ((hash (gethash key tramp-cache-data
))
244 (if (hash-table-p hash
)
246 (lambda (x y
) (add-to-list 'properties x
'append
))
247 (gethash key tramp-cache-data
)))
249 (setq tramp-cache-data-changed t
)
250 (remhash key tramp-cache-data
))
253 (defun tramp-cache-print (table)
254 "Print hash table TABLE."
255 (when (hash-table-p table
)
262 (prin1-to-string (prin1-to-string key
))
263 (prin1-to-string key
))
264 (if (hash-table-p value
)
265 (tramp-cache-print value
)
267 (prin1-to-string (prin1-to-string value
))
268 (prin1-to-string value
))))))
269 (setq result
(if result
(concat result
" " tmp
) tmp
))))
274 (defun tramp-list-connections ()
275 "Return a list of all known connection vectors according to `tramp-cache'."
279 (when (and (vectorp key
) (null (aref key
3)))
280 (add-to-list 'result key
)))
284 (defun tramp-dump-connection-properties ()
285 "Write persistent connection properties into file `tramp-persistency-file-name'."
286 ;; We shouldn't fail, otherwise (X)Emacs might not be able to be closed.
288 (when (and (hash-table-p tramp-cache-data
)
289 (not (zerop (hash-table-count tramp-cache-data
)))
290 tramp-cache-data-changed
291 (stringp tramp-persistency-file-name
))
292 (let ((cache (copy-hash-table tramp-cache-data
))
293 print-length print-level
)
294 ;; Remove temporary data. If there is the key "login-as", we
295 ;; don't save either, because all other properties might
296 ;; depend on the login name, and we want to give the
297 ;; possibility to use another login name later on.
300 (if (and (vectorp key
)
301 (not (tramp-file-name-localname key
))
302 (not (gethash "login-as" value
)))
304 (remhash "process-name" value
)
305 (remhash "process-buffer" value
)
306 (remhash "first-password-request" value
))
307 (remhash key cache
)))
312 ";; -*- emacs-lisp -*-"
313 ;; `time-stamp-string' might not exist in all (X)Emacs flavors.
318 (time-stamp-string "%02y/%02m/%02d %02H:%02M:%02S")
319 tramp-persistency-file-name
))
321 ";; Tramp connection history. Don't change this file.\n"
322 ";; You can delete it, forcing Tramp to reapply the checks.\n\n"
323 (with-output-to-string
324 (pp (read (format "(%s)" (tramp-cache-print cache
))))))
326 (point-min) (point-max) tramp-persistency-file-name
))))))
328 (unless noninteractive
329 (add-hook 'kill-emacs-hook
'tramp-dump-connection-properties
))
330 (add-hook 'tramp-cache-unload-hook
332 (remove-hook 'kill-emacs-hook
333 'tramp-dump-connection-properties
)))
336 (defun tramp-parse-connection-properties (method)
337 "Return a list of (user host) tuples allowed to access for METHOD.
338 This function is added always in `tramp-get-completion-function'
339 for all methods. Resulting data are derived from connection history."
343 (if (and (vectorp key
)
344 (string-equal method
(tramp-file-name-method key
))
345 (not (tramp-file-name-localname key
)))
346 (push (list (tramp-file-name-user key
)
347 (tramp-file-name-host key
))
352 ;; Read persistent connection history.
353 (when (and (stringp tramp-persistency-file-name
)
354 (zerop (hash-table-count tramp-cache-data
))
355 ;; When "emacs -Q" has been called, both variables are nil.
356 ;; We do not load the persistency file then, in order to
357 ;; have a clean test environment.
358 (or (and (boundp 'init-file-user
) (symbol-value 'init-file-user
))
359 (and (boundp 'site-run-file
) (symbol-value 'site-run-file
))))
362 (insert-file-contents tramp-persistency-file-name
)
363 (let ((list (read (current-buffer)))
365 (while (setq element
(pop list
))
366 (setq key
(pop element
))
367 (while (setq item
(pop element
))
368 (tramp-set-connection-property key
(pop item
) (car item
)))))
369 (setq tramp-cache-data-changed nil
))
371 ;; Most likely because the file doesn't exist yet. No message.
372 (clrhash tramp-cache-data
))
374 ;; File is corrupted.
375 (message "Tramp persistency file '%s' is corrupted: %s"
376 tramp-persistency-file-name
(error-message-string err
))
377 (clrhash tramp-cache-data
))))
379 (add-hook 'tramp-unload-hook
381 (unload-feature 'tramp-cache
'force
)))
383 (provide 'tramp-cache
)
385 ;;; tramp-cache.el ends here