lisp/net/tramp-ftp.el

   1 ;;; tramp-ftp.el --- Tramp convenience functions for Ange-FTP
   2
   3 ;; Copyright (C) 2002-2016 Free Software Foundation, Inc.
   4
   5 ;; Author: Michael Albinus <michael.albinus@gmx.de>
   6 ;; Keywords: comm, processes
   7 ;; Package: tramp
   8
   9 ;; This file is part of GNU Emacs.
  10
  11 ;; GNU Emacs is free software: you can redistribute it and/or modify
  12 ;; it under the terms of the GNU General Public License as published by
  13 ;; the Free Software Foundation, either version 3 of the License, or
  14 ;; (at your option) any later version.
  15
  16 ;; GNU Emacs is distributed in the hope that it will be useful,
  17 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 ;; GNU General Public License for more details.
  20
  21 ;; You should have received a copy of the GNU General Public License
  22 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  23
  24 ;;; Commentary:
  25
  26 ;; Convenience functions for calling Ange-FTP from Tramp.
  27 ;; Most of them are displaced from tramp.el.
  28
  29 ;;; Code:
  30
  31 (require 'tramp)
  32
  33 ;; Pacify byte-compiler.
  34 (eval-when-compile
  35   (require 'cl)
  36   (require 'custom))
  37 (defvar ange-ftp-ftp-name-arg)
  38 (defvar ange-ftp-ftp-name-res)
  39 (defvar ange-ftp-name-format)
  40
  41 ;; Disable Ange-FTP from file-name-handler-alist.
  42 ;; To handle EFS, the following functions need to be dealt with:
  43 ;;
  44 ;; * dired-before-readin-hook contains efs-dired-before-readin
  45 ;; * file-name-handler-alist contains efs-file-handler-function
  46 ;;   and efs-root-handler-function and efs-sifn-handler-function
  47 ;; * find-file-hooks contains efs-set-buffer-mode
  48 ;;
  49 ;; But it won't happen for EFS since the XEmacs maintainers
  50 ;; don't want to use a unified filename syntax.
  51 (defun tramp-disable-ange-ftp ()
  52   "Turn Ange-FTP off.
  53 This is useful for unified remoting.  See
  54 `tramp-file-name-structure' for details.  Requests suitable for
  55 Ange-FTP will be forwarded to Ange-FTP.  Also see the variables
  56 `tramp-ftp-method', `tramp-default-method', and
  57 `tramp-default-method-alist'.
  58
  59 This function is not needed in Emacsen which include Tramp, but is
  60 present for backward compatibility."
  61   (let ((a1 (rassq 'ange-ftp-hook-function file-name-handler-alist))
  62         (a2 (rassq 'ange-ftp-completion-hook-function file-name-handler-alist)))
  63     (setq file-name-handler-alist
  64           (delete a1 (delete a2 file-name-handler-alist)))))
  65
  66 (eval-after-load "ange-ftp"
  67   '(when (functionp 'tramp-disable-ange-ftp)
  68      (tramp-disable-ange-ftp)))
  69
  70 ;;;###autoload
  71 (defun tramp-ftp-enable-ange-ftp ()
  72   ;; The following code is commented out in Ange-FTP.
  73
  74   ;;; This regexp takes care of real ange-ftp file names (with a slash
  75   ;;; and colon).
  76   ;;; Don't allow the host name to end in a period--some systems use /.:
  77   (or (assoc "^/[^/:]*[^/:.]:" file-name-handler-alist)
  78       (setq file-name-handler-alist
  79             (cons '("^/[^/:]*[^/:.]:" . ange-ftp-hook-function)
  80                   file-name-handler-alist)))
  81
  82   ;;; This regexp recognizes absolute filenames with only one component,
  83   ;;; for the sake of hostname completion.
  84   (or (assoc "^/[^/:]*\\'" file-name-handler-alist)
  85       (setq file-name-handler-alist
  86             (cons '("^/[^/:]*\\'" . ange-ftp-completion-hook-function)
  87                   file-name-handler-alist)))
  88
  89   ;;; This regexp recognizes absolute filenames with only one component
  90   ;;; on Windows, for the sake of hostname completion.
  91   (and (memq system-type '(ms-dos windows-nt))
  92        (or (assoc "^[a-zA-Z]:/[^/:]*\\'" file-name-handler-alist)
  93            (setq file-name-handler-alist
  94                  (cons '("^[a-zA-Z]:/[^/:]*\\'" .
  95                          ange-ftp-completion-hook-function)
  96                        file-name-handler-alist)))))
  97
  98 (add-hook 'tramp-ftp-unload-hook 'tramp-ftp-enable-ange-ftp)
  99
 100 ;; Define FTP method ...
 101 ;;;###tramp-autoload
 102 (defconst tramp-ftp-method "ftp"
 103   "When this method name is used, forward all calls to Ange-FTP.")
 104
 105 ;; ... and add it to the method list.
 106 ;;;###tramp-autoload
 107 (unless (featurep 'xemacs)
 108   (add-to-list 'tramp-methods (cons tramp-ftp-method nil))
 109
 110   ;; Add some defaults for `tramp-default-method-alist'.
 111   (add-to-list 'tramp-default-method-alist
 112                (list "\\`ftp\\." nil tramp-ftp-method))
 113   (add-to-list 'tramp-default-method-alist
 114                (list nil "\\`\\(anonymous\\|ftp\\)\\'" tramp-ftp-method)))
 115
 116 ;; Add completion function for FTP method.
 117 ;;;###tramp-autoload
 118 (eval-after-load 'tramp
 119   '(tramp-set-completion-function
 120      tramp-ftp-method
 121      '((tramp-parse-netrc "~/.netrc"))))
 122
 123 ;;;###tramp-autoload
 124 (defun tramp-ftp-file-name-handler (operation &rest args)
 125   "Invoke the Ange-FTP handler for OPERATION.
 126 First arg specifies the OPERATION, second arg is a list of arguments to
 127 pass to the OPERATION."
 128   (save-match-data
 129     (or (boundp 'ange-ftp-name-format)
 130         (let (file-name-handler-alist) (require 'ange-ftp)))
 131     (let ((ange-ftp-name-format
 132            (list (nth 0 tramp-file-name-structure)
 133                  (nth 3 tramp-file-name-structure)
 134                  (nth 2 tramp-file-name-structure)
 135                  (nth 4 tramp-file-name-structure)))
 136           ;; ange-ftp uses `ange-ftp-ftp-name-arg' and `ange-ftp-ftp-name-res'
 137           ;; for optimization in `ange-ftp-ftp-name'. If Tramp wasn't active,
 138           ;; there could be incorrect values from previous calls in case the
 139           ;; "ftp" method is used in the Tramp file name. So we unset
 140           ;; those values.
 141           (ange-ftp-ftp-name-arg "")
 142           (ange-ftp-ftp-name-res nil))
 143       (cond
 144        ;; If argument is a symlink, `file-directory-p' and
 145        ;; `file-exists-p' call the traversed file recursively. So we
 146        ;; cannot disable the file-name-handler this case.  We set the
 147        ;; connection property "started" in order to put the remote
 148        ;; location into the cache, which is helpful for further
 149        ;; completion.  We don't use `with-parsed-tramp-file-name',
 150        ;; because this returns another user but the one declared in
 151        ;; "~/.netrc".
 152        ((memq operation '(file-directory-p file-exists-p))
 153         (if (apply 'ange-ftp-hook-function operation args)
 154             (let ((v (tramp-dissect-file-name (car args) t)))
 155               (aset v 0 tramp-ftp-method)
 156               (tramp-set-connection-property v "started" t))
 157           nil))
 158
 159        ;; If the second argument of `copy-file' or `rename-file' is a
 160        ;; remote file name but via FTP, ange-ftp doesn't check this.
 161        ;; We must copy it locally first, because there is no place in
 162        ;; ange-ftp for correct handling.
 163        ((and (memq operation '(copy-file rename-file))
 164              (tramp-tramp-file-p (cadr args))
 165              (not (tramp-ftp-file-name-p (cadr args))))
 166         (let* ((filename (car args))
 167                (newname (cadr args))
 168                (tmpfile (tramp-compat-make-temp-file filename))
 169                (args (cddr args)))
 170           ;; We must set `ok-if-already-exists' to t in the first
 171           ;; step, because the temp file has been created already.
 172           (if (eq operation 'copy-file)
 173               (apply operation filename tmpfile t (cdr args))
 174             (apply operation filename tmpfile t))
 175           (unwind-protect
 176               (rename-file tmpfile newname (car args))
 177             ;; Cleanup.
 178             (ignore-errors (delete-file tmpfile)))))
 179
 180        ;; Normally, the handlers must be discarded.
 181        (t (let* ((inhibit-file-name-handlers
 182                   (list 'tramp-file-name-handler
 183                         'tramp-completion-file-name-handler
 184                         (and (eq inhibit-file-name-operation operation)
 185                              inhibit-file-name-handlers)))
 186                  (inhibit-file-name-operation operation))
 187             (apply 'ange-ftp-hook-function operation args)))))))
 188
 189 ;; It must be a `defsubst' in order to push the whole code into
 190 ;; tramp-loaddefs.el.  Otherwise, there would be recursive autoloading.
 191 ;;;###tramp-autoload
 192 (defsubst tramp-ftp-file-name-p (filename)
 193   "Check if it's a filename that should be forwarded to Ange-FTP."
 194   (string= (tramp-file-name-method (tramp-dissect-file-name filename))
 195            tramp-ftp-method))
 196
 197 ;;;###tramp-autoload
 198 (unless (featurep 'xemacs)
 199   (add-to-list 'tramp-foreign-file-name-handler-alist
 200                (cons 'tramp-ftp-file-name-p 'tramp-ftp-file-name-handler)))
 201
 202 (add-hook 'tramp-unload-hook
 203           (lambda ()
 204             (unload-feature 'tramp-ftp 'force)))
 205
 206 (provide 'tramp-ftp)
 207
 208 ;;; TODO:
 209
 210 ;; * There are no backup files on FTP hosts.
 211
 212 ;;; tramp-ftp.el ends here