1 ;;; tramp-cache.el --- file information caching for Tramp
3 ;; Copyright (C) 2000, 2005-2015 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 nil, depending on the file existence, or
42 ;; "file-attributes" caches the result of the function
43 ;; `file-attributes'. These entries have a timestamp, and they
44 ;; expire after `remote-file-name-inhibit-cache' seconds if this
47 ;; - The key is a process. This are temporary properties related to
48 ;; an open connection. Examples: "scripts" keeps shell script
49 ;; definitions already sent to the remote shell, "last-cmd-time" is
50 ;; the time stamp a command has been sent to the remote process.
55 (autoload 'time-stamp-string
"time-stamp")
60 (defvar tramp-cache-data
(make-hash-table :test
'equal
)
61 "Hash table for remote files properties.")
64 (defcustom tramp-connection-properties nil
65 "List of static connection properties.
66 Every entry has the form (REGEXP PROPERTY VALUE). The regexp
67 matches remote file names. It can be nil. PROPERTY is a string,
68 and VALUE the corresponding value. They are used, if there is no
69 matching entry for PROPERTY in `tramp-cache-data'. For more
70 details see the info pages."
73 :type
'(repeat (list (choice :tag
"File Name regexp" regexp
(const nil
))
74 (choice :tag
" Property" string
)
75 (choice :tag
" Value" sexp
))))
77 (defcustom tramp-persistency-file-name
80 ((and (fboundp 'locate-user-emacs-file
))
81 (expand-file-name (tramp-compat-funcall 'locate-user-emacs-file
"tramp")))
82 ((and (boundp 'user-emacs-directory
)
83 (stringp (symbol-value 'user-emacs-directory
))
84 (file-directory-p (symbol-value 'user-emacs-directory
)))
85 (expand-file-name "tramp" (symbol-value 'user-emacs-directory
)))
86 ((and (not (featurep 'xemacs
)) (file-directory-p "~/.emacs.d/"))
89 ((and (boundp 'user-init-directory
)
90 (stringp (symbol-value 'user-init-directory
))
91 (file-directory-p (symbol-value 'user-init-directory
)))
92 (expand-file-name "tramp" (symbol-value 'user-init-directory
)))
93 ((and (featurep 'xemacs
) (file-directory-p "~/.xemacs/"))
95 ;; For users without `~/.emacs.d/' or `~/.xemacs/'.
97 "File which keeps connection history for Tramp connections."
101 (defvar tramp-cache-data-changed nil
102 "Whether persistent cache data have been changed.")
104 (defun tramp-get-hash-table (key)
105 "Returns the hash table for KEY.
106 If it doesn't exist yet, it is created and initialized with
107 matching entries of `tramp-connection-properties'."
108 (or (gethash key tramp-cache-data
)
110 (puthash key
(make-hash-table :test
'equal
) tramp-cache-data
)))
112 (dolist (elt tramp-connection-properties
)
115 (tramp-make-tramp-file-name
116 (aref key
0) (aref key
1) (aref key
2) nil
))
117 (tramp-set-connection-property key
(nth 1 elt
) (nth 2 elt
)))))
121 (defun tramp-get-file-property (key file property default
)
122 "Get the PROPERTY of FILE from the cache context of KEY.
123 Returns DEFAULT if not set."
124 ;; Unify localname. Remove hop from vector.
125 (setq key
(copy-sequence key
))
126 (aset key
3 (tramp-run-real-handler 'directory-file-name
(list file
)))
128 (let* ((hash (tramp-get-hash-table key
))
129 (value (when (hash-table-p hash
) (gethash property hash
))))
131 ;; We take the value only if there is any, and
132 ;; `remote-file-name-inhibit-cache' indicates that it is still
133 ;; valid. Otherwise, DEFAULT is set.
135 (or (null remote-file-name-inhibit-cache
)
136 (and (integerp remote-file-name-inhibit-cache
)
138 (tramp-time-diff (current-time) (car value
))
139 remote-file-name-inhibit-cache
))
140 (and (consp remote-file-name-inhibit-cache
)
142 remote-file-name-inhibit-cache
(car value
)))))
143 (setq value
(cdr value
))
144 (setq value default
))
146 (tramp-message key
8 "%s %s %s" file property value
)
147 (when (>= tramp-verbose
10)
148 (let* ((var (intern (concat "tramp-cache-get-count-" property
)))
149 (val (or (and (boundp var
) (symbol-value var
)) 0)))
154 (defun tramp-set-file-property (key file property value
)
155 "Set the PROPERTY of FILE to VALUE, in the cache context of KEY.
157 ;; Unify localname. Remove hop from vector.
158 (setq key
(copy-sequence key
))
159 (aset key
3 (tramp-run-real-handler 'directory-file-name
(list file
)))
161 (let ((hash (tramp-get-hash-table key
)))
162 ;; We put the timestamp there.
163 (puthash property
(cons (current-time) value
) hash
)
164 (tramp-message key
8 "%s %s %s" file property value
)
165 (when (>= tramp-verbose
10)
166 (let* ((var (intern (concat "tramp-cache-set-count-" property
)))
167 (val (or (and (boundp var
) (symbol-value var
)) 0)))
172 (defun tramp-flush-file-property (key file
)
173 "Remove all properties of FILE in the cache context of KEY."
174 (let* ((file (tramp-run-real-handler
175 'directory-file-name
(list file
)))
176 (truename (tramp-get-file-property key file
"file-truename" nil
)))
177 ;; Remove file properties of symlinks.
178 (when (and (stringp truename
)
179 (not (string-equal file
(directory-file-name truename
))))
180 (tramp-flush-file-property key truename
))
181 ;; Unify localname. Remove hop from vector.
182 (setq key
(copy-sequence key
))
185 (tramp-message key
8 "%s" file
)
186 (remhash key tramp-cache-data
)))
189 (defun tramp-flush-directory-property (key directory
)
190 "Remove all properties of DIRECTORY in the cache context of KEY.
191 Remove also properties of all files in subdirectories."
192 (let* ((directory (tramp-run-real-handler
193 'directory-file-name
(list directory
)))
194 (truename (tramp-get-file-property key directory
"file-truename" nil
)))
195 ;; Remove file properties of symlinks.
196 (when (and (stringp truename
)
197 (not (string-equal directory
(directory-file-name truename
))))
198 (tramp-flush-directory-property key truename
))
199 (tramp-message key
8 "%s" directory
)
202 (when (and (stringp (tramp-file-name-localname key
))
203 (string-match (regexp-quote directory
)
204 (tramp-file-name-localname key
)))
205 (remhash key tramp-cache-data
)))
208 ;; Reverting or killing a buffer should also flush file properties.
209 ;; They could have been changed outside Tramp. In eshell, "ls" would
210 ;; not show proper directory contents when a file has been copied or
211 ;; deleted before. We must apply `save-match-data', because it would
212 ;; corrupt other packages otherwise (reported from org).
213 (defun tramp-flush-file-function ()
214 "Flush all Tramp cache properties from `buffer-file-name'.
215 This is suppressed for temporary buffers."
217 (unless (or (null (buffer-name))
218 (string-match "^\\( \\|\\*\\)" (buffer-name)))
219 (let ((bfn (if (stringp (buffer-file-name))
223 (when (tramp-tramp-file-p bfn
)
224 (with-parsed-tramp-file-name bfn nil
225 (tramp-flush-file-property v localname
)))))))
227 (add-hook 'before-revert-hook
'tramp-flush-file-function
)
228 (add-hook 'eshell-pre-command-hook
'tramp-flush-file-function
)
229 (add-hook 'kill-buffer-hook
'tramp-flush-file-function
)
230 (add-hook 'tramp-cache-unload-hook
232 (remove-hook 'before-revert-hook
233 'tramp-flush-file-function
)
234 (remove-hook 'eshell-pre-command-hook
235 'tramp-flush-file-function
)
236 (remove-hook 'kill-buffer-hook
237 'tramp-flush-file-function
)))
242 (defun tramp-get-connection-property (key property default
)
243 "Get the named PROPERTY for the connection.
244 KEY identifies the connection, it is either a process or a vector.
245 If the value is not set for the connection, returns DEFAULT."
246 ;; Unify key by removing localname and hop from vector. Work with a
247 ;; copy in order to avoid side effects.
249 (setq key
(copy-sequence key
))
252 (let* ((hash (tramp-get-hash-table key
))
253 (value (if (hash-table-p hash
)
254 (gethash property hash default
)
256 (tramp-message key
7 "%s %s" property value
)
260 (defun tramp-set-connection-property (key property value
)
261 "Set the named PROPERTY of a connection to VALUE.
262 KEY identifies the connection, it is either a process or a vector.
263 PROPERTY is set persistent when KEY is a vector."
264 ;; Unify key by removing localname and hop from vector. Work with a
265 ;; copy in order to avoid side effects.
267 (setq key
(copy-sequence key
))
270 (let ((hash (tramp-get-hash-table key
)))
271 (puthash property value hash
)
272 (setq tramp-cache-data-changed t
)
273 (tramp-message key
7 "%s %s" property value
)
277 (defun tramp-connection-property-p (key property
)
278 "Check whether named PROPERTY of a connection is defined.
279 KEY identifies the connection, it is either a process or a vector."
280 (not (eq (tramp-get-connection-property key property
'undef
) 'undef
)))
283 (defun tramp-flush-connection-property (key)
284 "Remove all properties identified by KEY.
285 KEY identifies the connection, it is either a process or a vector."
286 ;; Unify key by removing localname and hop from vector. Work with a
287 ;; copy in order to avoid side effects.
289 (setq key
(copy-sequence key
))
294 (let ((hash (gethash key tramp-cache-data
))
296 (when (hash-table-p hash
)
297 (maphash (lambda (x _y
) (add-to-list 'properties x
'append
)) hash
))
299 (setq tramp-cache-data-changed t
)
300 (remhash key tramp-cache-data
))
303 (defun tramp-cache-print (table)
304 "Print hash table TABLE."
305 (when (hash-table-p table
)
309 ;; Remove text properties from KEY and VALUE.
310 ;; `substring-no-properties' does not exist in XEmacs.
311 (when (functionp 'substring-no-properties
)
313 (dotimes (i (length key
))
314 (when (stringp (aref key i
))
316 (tramp-compat-funcall
317 'substring-no-properties
(aref key i
))))))
319 (setq key
(tramp-compat-funcall 'substring-no-properties key
)))
320 (when (stringp value
)
322 (tramp-compat-funcall 'substring-no-properties value
))))
327 (prin1-to-string (prin1-to-string key
))
328 (prin1-to-string key
))
329 (if (hash-table-p value
)
330 (tramp-cache-print value
)
332 (prin1-to-string (prin1-to-string value
))
333 (prin1-to-string value
))))))
334 (setq result
(if result
(concat result
" " tmp
) tmp
))))
339 (defun tramp-list-connections ()
340 "Return a list of all known connection vectors according to `tramp-cache'."
344 (when (and (vectorp key
) (null (aref key
3)))
345 (add-to-list 'result key
)))
349 (defun tramp-dump-connection-properties ()
350 "Write persistent connection properties into file `tramp-persistency-file-name'."
351 ;; We shouldn't fail, otherwise (X)Emacs might not be able to be closed.
353 (when (and (hash-table-p tramp-cache-data
)
354 (not (zerop (hash-table-count tramp-cache-data
)))
355 tramp-cache-data-changed
356 (stringp tramp-persistency-file-name
))
357 (let ((cache (copy-hash-table tramp-cache-data
))
358 print-length print-level
)
359 ;; Remove temporary data. If there is the key "login-as", we
360 ;; don't save either, because all other properties might
361 ;; depend on the login name, and we want to give the
362 ;; possibility to use another login name later on.
365 (if (and (vectorp key
)
366 (not (tramp-file-name-localname key
))
367 (not (gethash "login-as" value
)))
369 (remhash "process-name" value
)
370 (remhash "process-buffer" value
)
371 (remhash "first-password-request" value
))
372 (remhash key cache
)))
375 (with-temp-file tramp-persistency-file-name
377 ";; -*- emacs-lisp -*-"
378 ;; `time-stamp-string' might not exist in all (X)Emacs flavors.
383 (time-stamp-string "%02y/%02m/%02d %02H:%02M:%02S")
384 tramp-persistency-file-name
))
386 ";; Tramp connection history. Don't change this file.\n"
387 ";; You can delete it, forcing Tramp to reapply the checks.\n\n"
388 (with-output-to-string
389 (pp (read (format "(%s)" (tramp-cache-print cache
)))))))))))
391 (unless noninteractive
392 (add-hook 'kill-emacs-hook
'tramp-dump-connection-properties
))
393 (add-hook 'tramp-cache-unload-hook
395 (remove-hook 'kill-emacs-hook
396 'tramp-dump-connection-properties
)))
399 (defun tramp-parse-connection-properties (method)
400 "Return a list of (user host) tuples allowed to access for METHOD.
401 This function is added always in `tramp-get-completion-function'
402 for all methods. Resulting data are derived from connection history."
406 (if (and (vectorp key
)
407 (string-equal method
(tramp-file-name-method key
))
408 (not (tramp-file-name-localname key
)))
409 (push (list (tramp-file-name-user key
)
410 (tramp-file-name-host key
))
415 ;; Read persistent connection history.
416 (when (and (stringp tramp-persistency-file-name
)
417 (zerop (hash-table-count tramp-cache-data
))
418 ;; When "emacs -Q" has been called, both variables are nil.
419 ;; We do not load the persistency file then, in order to
420 ;; have a clean test environment.
421 (or (and (boundp 'init-file-user
) (symbol-value 'init-file-user
))
422 (and (boundp 'site-run-file
) (symbol-value 'site-run-file
))))
425 (insert-file-contents tramp-persistency-file-name
)
426 (let ((list (read (current-buffer)))
429 (while (setq element
(pop list
))
430 (setq key
(pop element
))
431 (while (setq item
(pop element
))
432 ;; We set only values which are not contained in
433 ;; `tramp-connection-properties'. The cache is
434 ;; initialized properly by side effect.
435 (unless (tramp-connection-property-p key
(car item
))
436 (tramp-set-connection-property key
(pop item
) (car item
))))))
437 (setq tramp-cache-data-changed nil
))
439 ;; Most likely because the file doesn't exist yet. No message.
440 (clrhash tramp-cache-data
))
442 ;; File is corrupted.
443 (message "Tramp persistency file '%s' is corrupted: %s"
444 tramp-persistency-file-name
(error-message-string err
))
445 (clrhash tramp-cache-data
))))
447 (add-hook 'tramp-unload-hook
449 (unload-feature 'tramp-cache
'force
)))
451 (provide 'tramp-cache
)
453 ;;; tramp-cache.el ends here