1
0
mirror of https://git.savannah.gnu.org/git/emacs.git synced 2024-12-27 10:54:40 +00:00
emacs/lisp/net/tramp-cache.el
Michael Albinus 244acc5a05 Replace some `string-match-p' calls in Tramp
* lisp/net/tramp.el (tramp-debug-message, tramp-set-completion-function)
(tramp-get-completion-methods, tramp-get-completion-user-host):
* lisp/net/tramp-adb.el (tramp-adb-handle-make-process):
* lisp/net/tramp-sh.el (tramp-sh-handle-make-process)
(tramp-open-connection-setup-interactive-shell)
(tramp-convert-file-attributes): Use `string-prefix-p'.

* lisp/net/tramp.el (tramp-dissect-file-name)
(tramp-progress-reporter-update, tramp-handle-insert-directory):
* lisp/net/tramp-cache.el (tramp-get-hash-table)
(tramp-flush-directory-properties):
* lisp/net/tramp-cmds.el (tramp-append-tramp-buffers):
* lisp/net/tramp-sh.el (tramp-sh-handle-insert-directory)
(tramp-call-local-coding-command, tramp-get-inline-coding):
* lisp/net/tramp-smb.el (tramp-smb-handle-file-attributes)
(tramp-smb-handle-file-name-all-completions)
(tramp-smb-handle-file-writable-p)
(tramp-smb-handle-insert-directory)
(tramp-smb-handle-start-file-process, )
(tramp-smb-read-file-entry): Use `tramp-compat-string-search'.
2021-08-11 15:34:43 +02:00

567 lines
22 KiB
EmacsLisp

;;; tramp-cache.el --- file information caching for Tramp -*- lexical-binding:t -*-
;; Copyright (C) 2000, 2005-2021 Free Software Foundation, Inc.
;; Author: Daniel Pittman <daniel@inanna.danann.net>
;; Michael Albinus <michael.albinus@gmx.de>
;; Maintainer: Michael Albinus <michael.albinus@gmx.de>
;; Keywords: comm, processes
;; Package: tramp
;; This file is part of GNU Emacs.
;; GNU Emacs is free software: you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation, either version 3 of the License, or
;; (at your option) any later version.
;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
;; GNU General Public License for more details.
;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs. If not, see <https://www.gnu.org/licenses/>.
;;; Commentary:
;; An implementation of information caching for remote files.
;; Each connection, identified by a `tramp-file-name' structure or by
;; a process, has a unique cache. We distinguish 4 kind of caches,
;; depending on the key:
;;
;; - localname is nil. These are reusable properties. Examples:
;; "remote-shell" identifies the POSIX shell to be called on the
;; remote host, or "perl" is the command to be called on the remote
;; host when starting a Perl script. These properties are saved in
;; the file `tramp-persistency-file-name'.
;;
;; - localname is a string. These are temporary properties, which are
;; related to the file localname is referring to. Examples:
;; "file-exists-p" is t or nil, depending on the file existence, or
;; "file-attributes" caches the result of the function
;; `file-attributes'. These entries have a timestamp, and they
;; expire after `remote-file-name-inhibit-cache' seconds if this
;; variable is set.
;;
;; - The key is a process. These are temporary properties related to
;; an open connection. Examples: "scripts" keeps shell script
;; definitions already sent to the remote shell, "last-cmd-time" is
;; the time stamp a command has been sent to the remote process.
;; "lock-pid" is the timestamp a (network) process is created, it is
;; used instead of the pid in file locks.
;;
;; - The key is nil. These are temporary properties related to the
;; local machine. Examples: "parse-passwd" and "parse-group" keep
;; the results of parsing "/etc/passwd" and "/etc/group",
;; "{uid,gid}-{integer,string}" are the local uid and gid, and
;; "locale" is the used shell locale.
;;
;; - The key is `tramp-cache-undefined'. All functions return the
;; expected values, but nothing is cached.
;; Some properties are handled special:
;;
;; - "process-name", "process-buffer" and "first-password-request" are
;; not saved in the file `tramp-persistency-file-name', although
;; being connection properties related to a `tramp-file-name'
;; structure.
;;
;; - Reusable properties, which should not be saved, are kept in the
;; process key retrieved by `tramp-get-process' (the main connection
;; process). Other processes could reuse these properties, avoiding
;; recomputation when a new asynchronous process is created by
;; `make-process'. Examples are "unsafe-temporary-file",
;; "remote-path", "device" (tramp-adb.el) or "share" (tramp-gvfs.el).
;;; Code:
(require 'tramp)
(autoload 'time-stamp-string "time-stamp")
;;; -- Cache --
;;;###tramp-autoload
(defvar tramp-cache-data (make-hash-table :test #'equal)
"Hash table for remote files properties.")
;;;###tramp-autoload
(defcustom tramp-connection-properties nil
"List of static connection properties.
Every entry has the form (REGEXP PROPERTY VALUE). The regexp
matches remote file names. It can be nil. PROPERTY is a string,
and VALUE the corresponding value. They are used, if there is no
matching entry for PROPERTY in `tramp-cache-data'. For more
details see the info pages."
:group 'tramp
:version "24.4"
:type '(repeat (list (choice :tag "File Name regexp" regexp (const nil))
(choice :tag " Property" string)
(choice :tag " Value" sexp))))
;;;###tramp-autoload
(defcustom tramp-persistency-file-name
(expand-file-name (locate-user-emacs-file "tramp"))
"File which keeps connection history for Tramp connections."
:group 'tramp
:type 'file)
(defvar tramp-cache-data-changed nil
"Whether persistent cache data have been changed.")
;;;###tramp-autoload
(defconst tramp-cache-undefined 'undef
"The symbol marking undefined hash keys and values.")
(defun tramp-get-hash-table (key)
"Return the hash table for KEY.
If it doesn't exist yet, it is created and initialized with
matching entries of `tramp-connection-properties'.
If KEY is `tramp-cache-undefined', don't create anything, and return nil."
(unless (eq key tramp-cache-undefined)
(or (gethash key tramp-cache-data)
(let ((hash
(puthash key (make-hash-table :test #'equal) tramp-cache-data)))
(when (tramp-file-name-p key)
(dolist (elt tramp-connection-properties)
(when (tramp-compat-string-search
(or (nth 0 elt) "")
(tramp-make-tramp-file-name key 'noloc 'nohop))
(tramp-set-connection-property key (nth 1 elt) (nth 2 elt)))))
hash))))
;;;###tramp-autoload
(defun tramp-get-file-property (key file property default)
"Get the PROPERTY of FILE from the cache context of KEY.
Return DEFAULT if not set."
;; Unify localname. Remove hop from `tramp-file-name' structure.
(setq file (tramp-compat-file-name-unquote file)
key (copy-tramp-file-name key))
(setf (tramp-file-name-localname key)
(tramp-run-real-handler #'directory-file-name (list file))
(tramp-file-name-hop key) nil)
(let* ((hash (tramp-get-hash-table key))
(cached (and (hash-table-p hash) (gethash property hash)))
(cached-at (and (consp cached) (format-time-string "%T" (car cached))))
(value default)
cache-used)
(when ;; We take the value only if there is any, and
;; `remote-file-name-inhibit-cache' indicates that it is
;; still valid. Otherwise, DEFAULT is set.
(and (consp cached)
(or (null remote-file-name-inhibit-cache)
(and (integerp remote-file-name-inhibit-cache)
(time-less-p
nil
(time-add (car cached) remote-file-name-inhibit-cache)))
(and (consp remote-file-name-inhibit-cache)
(time-less-p
remote-file-name-inhibit-cache (car cached)))))
(setq value (cdr cached)
cache-used t))
(tramp-message
key 8 "%s %s %s; inhibit: %s; cache used: %s; cached at: %s"
file property value remote-file-name-inhibit-cache cache-used cached-at)
;; For analysis purposes, count the number of getting this file attribute.
(when (>= tramp-verbose 10)
(let* ((var (intern (concat "tramp-cache-get-count-" property)))
(val (or (and (boundp var) (numberp (symbol-value var))
(symbol-value var))
0)))
(set var (1+ val))))
value))
(add-hook 'tramp-cache-unload-hook
(lambda ()
(dolist (var (all-completions "tramp-cache-get-count-" obarray))
(unintern var obarray))))
;;;###tramp-autoload
(defun tramp-set-file-property (key file property value)
"Set the PROPERTY of FILE to VALUE, in the cache context of KEY.
Return VALUE."
;; Unify localname. Remove hop from `tramp-file-name' structure.
(setq file (tramp-compat-file-name-unquote file)
key (copy-tramp-file-name key))
(setf (tramp-file-name-localname key)
(tramp-run-real-handler #'directory-file-name (list file))
(tramp-file-name-hop key) nil)
(let ((hash (tramp-get-hash-table key)))
;; We put the timestamp there.
(puthash property (cons (current-time) value) hash)
(tramp-message key 8 "%s %s %s" file property value)
;; For analysis purposes, count the number of setting this file attribute.
(when (>= tramp-verbose 10)
(let* ((var (intern (concat "tramp-cache-set-count-" property)))
(val (or (and (boundp var) (numberp (symbol-value var))
(symbol-value var))
0)))
(set var (1+ val))))
value))
(add-hook 'tramp-cache-unload-hook
(lambda ()
(dolist (var (all-completions "tramp-cache-set-count-" obarray))
(unintern var obarray))))
;;;###tramp-autoload
(defun tramp-flush-file-property (key file property)
"Remove PROPERTY of FILE in the cache context of KEY."
;; Unify localname. Remove hop from `tramp-file-name' structure.
(setq file (tramp-compat-file-name-unquote file)
key (copy-tramp-file-name key))
(setf (tramp-file-name-localname key)
(tramp-run-real-handler #'directory-file-name (list file))
(tramp-file-name-hop key) nil)
(remhash property (tramp-get-hash-table key))
(tramp-message key 8 "%s %s" file property)
(when (>= tramp-verbose 10)
(let ((var (intern (concat "tramp-cache-set-count-" property))))
(makunbound var))))
(defun tramp-flush-file-upper-properties (key file)
"Remove some properties of FILE's upper directory."
(when (file-name-absolute-p file)
(let ((file (directory-file-name (file-name-directory file))))
;; Unify localname. Remove hop from `tramp-file-name' structure.
(setq file (tramp-compat-file-name-unquote file)
key (copy-tramp-file-name key))
(setf (tramp-file-name-localname key) file
(tramp-file-name-hop key) nil)
(dolist (property (hash-table-keys (tramp-get-hash-table key)))
(when (string-match-p
"^\\(directory-\\|file-name-all-completions\\|file-entries\\)"
property)
(tramp-flush-file-property key file property))))))
;;;###tramp-autoload
(defun tramp-flush-file-properties (key file)
"Remove all properties of FILE in the cache context of KEY."
(let* ((file (tramp-run-real-handler #'directory-file-name (list file)))
(truename (tramp-get-file-property key file "file-truename" nil)))
;; Unify localname. Remove hop from `tramp-file-name' structure.
(setq file (tramp-compat-file-name-unquote file)
key (copy-tramp-file-name key))
(setf (tramp-file-name-localname key) file
(tramp-file-name-hop key) nil)
(tramp-message key 8 "%s" file)
(remhash key tramp-cache-data)
;; Remove file properties of symlinks.
(when (and (stringp truename)
(not (string-equal file (directory-file-name truename))))
(tramp-flush-file-properties key truename))
;; Remove selected properties of upper directory.
(tramp-flush-file-upper-properties key file)))
;;;###tramp-autoload
(defun tramp-flush-directory-properties (key directory)
"Remove all properties of DIRECTORY in the cache context of KEY.
Remove also properties of all files in subdirectories."
(setq directory (tramp-compat-file-name-unquote directory))
(let* ((directory (tramp-run-real-handler
#'directory-file-name (list directory)))
(truename (tramp-get-file-property key directory "file-truename" nil)))
(tramp-message key 8 "%s" directory)
(dolist (key (hash-table-keys tramp-cache-data))
(when (and (tramp-file-name-p key)
(stringp (tramp-file-name-localname key))
(tramp-compat-string-search
directory (tramp-file-name-localname key)))
(remhash key tramp-cache-data)))
;; Remove file properties of symlinks.
(when (and (stringp truename)
(not (string-equal directory (directory-file-name truename))))
(tramp-flush-directory-properties key truename))
;; Remove selected properties of upper directory.
(tramp-flush-file-upper-properties key directory)))
;; Reverting or killing a buffer should also flush file properties.
;; They could have been changed outside Tramp. In eshell, "ls" would
;; not show proper directory contents when a file has been copied or
;; deleted before. We must apply `save-match-data', because it would
;; corrupt other packages otherwise (reported from org).
(defun tramp-flush-file-function ()
"Flush all Tramp cache properties from `buffer-file-name'.
This is suppressed for temporary buffers."
(save-match-data
(unless (or (null (buffer-name))
(string-match-p "^\\( \\|\\*\\)" (buffer-name)))
(let ((bfn (if (stringp (buffer-file-name))
(buffer-file-name)
default-directory))
(tramp-verbose 0))
(when (tramp-tramp-file-p bfn)
(with-parsed-tramp-file-name bfn nil
(tramp-flush-file-properties v localname)))))))
(add-hook 'before-revert-hook #'tramp-flush-file-function)
(add-hook 'eshell-pre-command-hook #'tramp-flush-file-function)
(add-hook 'kill-buffer-hook #'tramp-flush-file-function)
(add-hook 'tramp-cache-unload-hook
(lambda ()
(remove-hook 'before-revert-hook
#'tramp-flush-file-function)
(remove-hook 'eshell-pre-command-hook
#'tramp-flush-file-function)
(remove-hook 'kill-buffer-hook
#'tramp-flush-file-function)))
;;; -- Properties --
;;;###tramp-autoload
(defun tramp-get-connection-property (key property default)
"Get the named PROPERTY for the connection.
KEY identifies the connection, it is either a process or a
`tramp-file-name' structure. A special case is nil, which is
used to cache connection properties of the local machine.
If KEY is `tramp-cache-undefined', or if the value is not set for
the connection, return DEFAULT."
;; Unify key by removing localname and hop from `tramp-file-name'
;; structure. Work with a copy in order to avoid side effects.
(when (tramp-file-name-p key)
(setq key (copy-tramp-file-name key))
(setf (tramp-file-name-localname key) nil
(tramp-file-name-hop key) nil))
(let* ((hash (tramp-get-hash-table key))
(cached (if (hash-table-p hash)
(gethash property hash tramp-cache-undefined)
tramp-cache-undefined))
(value default)
cache-used)
(when (and (not (eq cached tramp-cache-undefined))
;; If the key is an auxiliary process object, check
;; whether the process is still alive.
(not (and (processp key) (not (process-live-p key)))))
(setq value cached
cache-used t))
(tramp-message key 7 "%s %s; cache used: %s" property value cache-used)
value))
;;;###tramp-autoload
(defun tramp-set-connection-property (key property value)
"Set the named PROPERTY of a connection to VALUE.
KEY identifies the connection, it is either a process or a
`tramp-file-name' structure. A special case is nil, which is
used to cache connection properties of the local machine. If KEY
is `tramp-cache-undefined', nothing is set.
PROPERTY is set persistent when KEY is a `tramp-file-name' structure.
Return VALUE."
;; Unify key by removing localname and hop from `tramp-file-name'
;; structure. Work with a copy in order to avoid side effects.
(when (tramp-file-name-p key)
(setq key (copy-tramp-file-name key))
(setf (tramp-file-name-localname key) nil
(tramp-file-name-hop key) nil))
(when-let ((hash (tramp-get-hash-table key)))
(puthash property value hash))
(setq tramp-cache-data-changed
(or tramp-cache-data-changed (tramp-file-name-p key)))
(tramp-message key 7 "%s %s" property value)
value)
;;;###tramp-autoload
(defun tramp-connection-property-p (key property)
"Check whether named PROPERTY of a connection is defined.
KEY identifies the connection, it is either a process or a
`tramp-file-name' structure. A special case is nil, which is
used to cache connection properties of the local machine."
(not (eq (tramp-get-connection-property key property tramp-cache-undefined)
tramp-cache-undefined)))
;;;###tramp-autoload
(defun tramp-flush-connection-property (key property)
"Remove the named PROPERTY of a connection identified by KEY.
KEY identifies the connection, it is either a process or a
`tramp-file-name' structure. A special case is nil, which is
used to cache connection properties of the local machine.
PROPERTY is set persistent when KEY is a `tramp-file-name' structure."
;; Unify key by removing localname and hop from `tramp-file-name'
;; structure. Work with a copy in order to avoid side effects.
(when (tramp-file-name-p key)
(setq key (copy-tramp-file-name key))
(setf (tramp-file-name-localname key) nil
(tramp-file-name-hop key) nil))
(when-let ((hash (tramp-get-hash-table key)))
(remhash property hash))
(setq tramp-cache-data-changed
(or tramp-cache-data-changed (tramp-file-name-p key)))
(tramp-message key 7 "%s" property))
;;;###tramp-autoload
(defun tramp-flush-connection-properties (key)
"Remove all properties identified by KEY.
KEY identifies the connection, it is either a process or a
`tramp-file-name' structure. A special case is nil, which is
used to cache connection properties of the local machine."
;; Unify key by removing localname and hop from `tramp-file-name'
;; structure. Work with a copy in order to avoid side effects.
(when (tramp-file-name-p key)
(setq key (copy-tramp-file-name key))
(setf (tramp-file-name-localname key) nil
(tramp-file-name-hop key) nil))
(tramp-message
key 7 "%s %s" key
(when-let ((hash (gethash key tramp-cache-data)))
(hash-table-keys hash)))
(setq tramp-cache-data-changed
(or tramp-cache-data-changed (tramp-file-name-p key)))
(remhash key tramp-cache-data))
;;;###tramp-autoload
(defun tramp-cache-print (table)
"Print hash table TABLE."
(when (hash-table-p table)
(let (result)
(maphash
(lambda (key value)
;; Remove text properties from KEY and VALUE.
(when (tramp-file-name-p key)
(dolist
(slot
(mapcar #'car (cdr (cl-struct-slot-info 'tramp-file-name))))
(when (stringp (cl-struct-slot-value 'tramp-file-name slot key))
(setf (cl-struct-slot-value 'tramp-file-name slot key)
(substring-no-properties
(cl-struct-slot-value 'tramp-file-name slot key))))))
(when (stringp key)
(setq key (substring-no-properties key)))
(when (stringp value)
(setq value (substring-no-properties value)))
;; Dump.
(let ((tmp (format
"(%s %s)"
(if (processp key)
(prin1-to-string (prin1-to-string key))
(prin1-to-string key))
(if (hash-table-p value)
(tramp-cache-print value)
(if (bufferp value)
(prin1-to-string (prin1-to-string value))
(prin1-to-string value))))))
(setq result (if result (concat result " " tmp) tmp))))
table)
result)))
;;;###tramp-autoload
(defun tramp-list-connections ()
"Return all known `tramp-file-name' structs according to `tramp-cache'."
(let ((tramp-verbose 0))
(delq nil (mapcar
(lambda (key)
(and (tramp-file-name-p key)
(null (tramp-file-name-localname key))
(tramp-connection-property-p key "process-buffer")
key))
(hash-table-keys tramp-cache-data)))))
(defun tramp-dump-connection-properties ()
"Write persistent connection properties into file \
`tramp-persistency-file-name'."
;; We shouldn't fail, otherwise Emacs might not be able to be closed.
(ignore-errors
(when (and (hash-table-p tramp-cache-data)
(not (zerop (hash-table-count tramp-cache-data)))
tramp-cache-data-changed
(stringp tramp-persistency-file-name))
(let ((cache (copy-hash-table tramp-cache-data))
print-length print-level)
;; Remove temporary data. If there is the key "login-as", we
;; don't save either, because all other properties might
;; depend on the login name, and we want to give the
;; possibility to use another login name later on. Key
;; "started" exists for the "ftp" method only, which must not
;; be kept persistent.
(maphash
(lambda (key value)
(if (and (tramp-file-name-p key) (hash-table-p value)
(not (string-equal
(tramp-file-name-method key) tramp-archive-method))
(not (tramp-file-name-localname key))
(not (gethash "login-as" value))
(not (gethash "started" value)))
(progn
(remhash "process-name" value)
(remhash "process-buffer" value)
(remhash "first-password-request" value))
(remhash key cache)))
cache)
;; Dump it.
(with-temp-file tramp-persistency-file-name
(insert
;; Starting with Emacs 28, we could use `lisp-data'.
(format ";; -*- emacs-lisp -*- <%s %s>\n"
(time-stamp-string "%02y/%02m/%02d %02H:%02M:%02S")
tramp-persistency-file-name)
";; Tramp connection history. Don't change this file.\n"
";; Run `M-x tramp-cleanup-all-connections' instead.\n\n"
(with-output-to-string
(pp (read (format "(%s)" (tramp-cache-print cache)))))))))))
(unless noninteractive
(add-hook 'kill-emacs-hook #'tramp-dump-connection-properties))
(add-hook 'tramp-cache-unload-hook
(lambda ()
(remove-hook 'kill-emacs-hook
#'tramp-dump-connection-properties)))
;;;###tramp-autoload
(defun tramp-parse-connection-properties (method)
"Return a list of (user host) tuples allowed to access for METHOD.
This function is added always in `tramp-get-completion-function'
for all methods. Resulting data are derived from connection history."
(mapcar
(lambda (key)
(and (tramp-file-name-p key)
(string-equal method (tramp-file-name-method key))
(not (tramp-file-name-localname key))
(list (tramp-file-name-user key)
(tramp-file-name-host key))))
(hash-table-keys tramp-cache-data)))
;; When "emacs -Q" has been called, both variables are nil. We do not
;; load the persistency file then, in order to have a clean test environment.
;;;###tramp-autoload
(defvar tramp-cache-read-persistent-data (or init-file-user site-run-file)
"Whether to read persistent data at startup time.")
;; Read persistent connection history.
(when (and (stringp tramp-persistency-file-name)
(zerop (hash-table-count tramp-cache-data))
tramp-cache-read-persistent-data)
(condition-case err
(with-temp-buffer
(insert-file-contents-literally tramp-persistency-file-name)
(let ((list (read (current-buffer)))
(tramp-verbose 0)
element key item)
(while (setq element (pop list))
(setq key (pop element))
(when (tramp-file-name-p key)
(while (setq item (pop element))
;; We set only values which are not contained in
;; `tramp-connection-properties'. The cache is
;; initialized properly by side effect.
(unless (tramp-connection-property-p key (car item))
(tramp-set-connection-property key (pop item) (car item)))))))
(setq tramp-cache-data-changed nil))
(file-error
;; Most likely because the file doesn't exist yet. No message.
(clrhash tramp-cache-data))
(error
;; File is corrupted.
(message "Tramp persistency file `%s' is corrupted: %s"
tramp-persistency-file-name (error-message-string err))
(clrhash tramp-cache-data))))
(add-hook 'tramp-unload-hook
(lambda ()
(unload-feature 'tramp-cache 'force)))
(provide 'tramp-cache)
;;; tramp-cache.el ends here