tramp-compat.el 17.1 KB
Newer Older
1
;;; tramp-compat.el --- Tramp compatibility functions
2

Glenn Morris's avatar
Glenn Morris committed
3
;; Copyright (C) 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
4 5 6 7 8 9

;; Author: Michael Albinus <michael.albinus@gmx.de>
;; Keywords: comm, processes

;; This file is part of GNU Emacs.

10
;; GNU Emacs is free software: you can redistribute it and/or modify
11
;; it under the terms of the GNU General Public License as published by
12 13
;; the Free Software Foundation, either version 3 of the License, or
;; (at your option) any later version.
14 15 16 17 18 19 20

;; 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
21
;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
22 23 24

;;; Commentary:

25 26 27
;; Tramp's main Emacs version for development is GNU Emacs 24.  This
;; package provides compatibility functions for GNU Emacs 22, GNU
;; Emacs 23 and XEmacs 21.4+.
28 29 30

;;; Code:

31
(eval-when-compile
32 33

  ;; Pacify byte-compiler.
34 35 36 37
  (require 'cl))

(eval-and-compile

38
  (require 'custom)
39

40 41 42 43
  ;; Load the appropriate timer package.
  (if (featurep 'xemacs)
      (require 'timer-funcs)
    (require 'timer))
44

45 46
  (autoload 'tramp-tramp-file-p "tramp")
  (autoload 'tramp-file-name-handler "tramp")
47
  (autoload 'tramp-handle-file-remote-p "tramp")
48

49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74
  ;; tramp-util offers integration into other (X)Emacs packages like
  ;; compile.el, gud.el etc.  Not necessary in Emacs 23.
  (eval-after-load "tramp"
    ;; We check whether `start-file-process' is an alias.
    '(when (or (not (fboundp 'start-file-process))
	       (symbolp (symbol-function 'start-file-process)))
       (require 'tramp-util)
       (add-hook 'tramp-unload-hook
		 '(lambda ()
		    (when (featurep 'tramp-util)
		      (unload-feature 'tramp-util 'force))))))

  ;; Make sure that we get integration with the VC package.  When it
  ;; is loaded, we need to pull in the integration module.  Not
  ;; necessary in Emacs 23.
  (eval-after-load "vc"
    (eval-after-load "tramp"
      ;; We check whether `start-file-process' is an alias.
      '(when (or (not (fboundp 'start-file-process))
		 (symbolp (symbol-function 'start-file-process)))
	 (require 'tramp-vc)
	 (add-hook 'tramp-unload-hook
		   '(lambda ()
		      (when (featurep 'tramp-vc)
			(unload-feature 'tramp-vc 'force)))))))

75 76 77 78 79 80 81 82
  ;; Avoid byte-compiler warnings if the byte-compiler supports this.
  ;; Currently, XEmacs supports this.
  (when (featurep 'xemacs)
    (unless (boundp 'byte-compile-default-warnings)
      (defvar byte-compile-default-warnings nil))
    (delq 'unused-vars byte-compile-default-warnings))

  ;; `last-coding-system-used' is unknown in XEmacs.
83
  (unless (boundp 'last-coding-system-used)
84
    (defvar last-coding-system-used nil))
85

86 87 88
  ;; `directory-sep-char' is an obsolete variable in Emacs.  But it is
  ;; used in XEmacs, so we set it here and there.  The following is
  ;; needed to pacify Emacs byte-compiler.
89 90
  (unless (boundp 'byte-compile-not-obsolete-var)
    (defvar byte-compile-not-obsolete-var nil))
91
  (setq byte-compile-not-obsolete-var 'directory-sep-char)
92 93 94 95
  ;; Emacs 23.2.
  (unless (boundp 'byte-compile-not-obsolete-vars)
    (defvar byte-compile-not-obsolete-vars nil))
  (setq byte-compile-not-obsolete-vars '(directory-sep-char))
96

97
  ;; `with-temp-message' does not exists in XEmacs.
98 99
  (condition-case nil
      (with-temp-message (current-message) nil)
100
    (error (defmacro with-temp-message (message &rest body) `(progn ,@body))))
101

102 103 104 105 106 107 108 109 110
  ;; For not existing functions, or functions with a changed argument
  ;; list, there are compiler warnings.  We want to avoid them in
  ;; cases we know what we do.
  (defmacro tramp-compat-funcall (function &rest arguments)
    (if (featurep 'xemacs)
	`(funcall (symbol-function ,function) ,@arguments)
      `(when (or (subrp ,function) (functionp ,function))
	 (with-no-warnings (funcall ,function ,@arguments)))))

111
  ;; `set-buffer-multibyte' comes from Emacs Leim.
112
  (unless (fboundp 'set-buffer-multibyte)
113
    (defalias 'set-buffer-multibyte 'ignore))
114

115
  ;; `font-lock-add-keywords' does not exist in XEmacs.
116
  (unless (fboundp 'font-lock-add-keywords)
117 118
    (defalias 'font-lock-add-keywords 'ignore))

119 120 121 122
  ;; The following functions cannot be aliases of the corresponding
  ;; `tramp-handle-*' functions, because this would bypass the locking
  ;; mechanism.

123 124 125 126 127
  ;; `file-remote-p' has been introduced with Emacs 22.  The version
  ;; of XEmacs is not a magic file name function (yet); this is
  ;; corrected in tramp-util.el.  Here it is sufficient if the
  ;; function exists.
  (unless (fboundp 'file-remote-p)
128 129 130 131 132
    (defalias 'file-remote-p
      (lambda (file &optional identification connected)
	(when (tramp-tramp-file-p file)
	  (tramp-file-name-handler
	   'file-remote-p file identification connected)))))
133

134
  ;; `process-file' does not exist in XEmacs.
135
  (unless (fboundp 'process-file)
136 137 138 139 140 141
    (defalias 'process-file
      (lambda (program &optional infile buffer display &rest args)
	(when (tramp-tramp-file-p default-directory)
	  (apply
	   'tramp-file-name-handler
	   'process-file program infile buffer display args)))))
142 143 144

  ;; `start-file-process' is new in Emacs 23.
  (unless (fboundp 'start-file-process)
145 146 147 148 149 150
    (defalias 'start-file-process
      (lambda (name buffer program &rest program-args)
	(when (tramp-tramp-file-p default-directory)
	  (apply
	   'tramp-file-name-handler
	   'start-file-process name buffer program program-args)))))
151 152 153

  ;; `set-file-times' is also new in Emacs 23.
  (unless (fboundp 'set-file-times)
154 155 156 157
    (defalias 'set-file-times
      (lambda (filename &optional time)
	(when (tramp-tramp-file-p filename)
	  (tramp-file-name-handler
158 159 160 161 162 163 164 165 166 167
	   'set-file-times filename time)))))

  ;; We currently use "[" and "]" in the filename format for IPv6
  ;; hosts of GNU Emacs.  This means, that Emacs wants to expand
  ;; wildcards if `find-file-wildcards' is non-nil, and then barfs
  ;; because no expansion could be found.  We detect this situation
  ;; and do something really awful: we have `file-expand-wildcards'
  ;; return the original filename if it can't expand anything.  Let's
  ;; just hope that this doesn't break anything else.
  ;; It is not needed anymore since GNU Emacs 23.2.
168 169 170
  (unless (or (featurep 'xemacs)
	      ;; `featurep' has only one argument in XEmacs.
	      (funcall 'featurep 'files 'remote-wildcards))
171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188
    (defadvice file-expand-wildcards
      (around tramp-advice-file-expand-wildcards activate)
      (let ((name (ad-get-arg 0)))
	;; If it's a Tramp file, look if wildcards need to be expanded
	;; at all.
	(if (and
	     (tramp-tramp-file-p name)
	     (not (string-match
		   "[[*?]" (tramp-handle-file-remote-p name 'localname))))
	    (setq ad-return-value (list name))
	  ;; Otherwise, just run the original function.
	  ad-do-it)))
    (add-hook
     'tramp-unload-hook
     (lambda ()
       (ad-remove-advice
	'file-expand-wildcards 'around 'tramp-advice-file-expand-wildcards)
       (ad-activate 'file-expand-wildcards)))))
189

190 191 192 193 194 195
(defsubst tramp-compat-line-beginning-position ()
  "Return point at beginning of line (compat function).
Calls `line-beginning-position' or `point-at-bol' if defined, else
own implementation."
  (cond
   ((fboundp 'line-beginning-position)
196 197
    (tramp-compat-funcall 'line-beginning-position))
   ((fboundp 'point-at-bol) (tramp-compat-funcall 'point-at-bol))
198 199
   (t (save-excursion (beginning-of-line) (point)))))

200 201 202 203 204
(defsubst tramp-compat-line-end-position ()
  "Return point at end of line (compat function).
Calls `line-end-position' or `point-at-eol' if defined, else
own implementation."
  (cond
205 206
   ((fboundp 'line-end-position) (tramp-compat-funcall 'line-end-position))
   ((fboundp 'point-at-eol) (tramp-compat-funcall 'point-at-eol))
207 208 209 210 211 212 213
   (t (save-excursion (end-of-line) (point)))))

(defsubst tramp-compat-temporary-file-directory ()
  "Return name of directory for temporary files (compat function).
For Emacs, this is the variable `temporary-file-directory', for XEmacs
this is the function `temp-directory'."
  (cond
214
   ((boundp 'temporary-file-directory) (symbol-value 'temporary-file-directory))
215
   ((fboundp 'temp-directory) (tramp-compat-funcall 'temp-directory))
216 217 218 219 220 221 222 223 224 225 226
   ((let ((d (getenv "TEMP"))) (and d (file-directory-p d)))
    (file-name-as-directory (getenv "TEMP")))
   ((let ((d (getenv "TMP"))) (and d (file-directory-p d)))
    (file-name-as-directory (getenv "TMP")))
   ((let ((d (getenv "TMPDIR"))) (and d (file-directory-p d)))
    (file-name-as-directory (getenv "TMPDIR")))
   ((file-exists-p "c:/temp") (file-name-as-directory "c:/temp"))
   (t (message (concat "Neither `temporary-file-directory' nor "
		       "`temp-directory' is defined -- using /tmp."))
      (file-name-as-directory "/tmp"))))

227 228 229
;; `make-temp-file' exists in Emacs only.  On XEmacs, we use our own
;; implementation with `make-temp-name', creating the temporary file
;; immediately in order to avoid a security hole.
230
(defsubst tramp-compat-make-temp-file (filename &optional dir-flag)
231 232
  "Create a temporary file (compat function).
Add the extension of FILENAME, if existing."
233 234 235 236 237 238
  (let* (file-name-handler-alist
	 (prefix (expand-file-name
		  (symbol-value 'tramp-temp-name-prefix)
		  (tramp-compat-temporary-file-directory)))
	 (extension (file-name-extension filename t))
	 result)
239
    (if (fboundp 'make-temp-file)
240
	(setq result
241
	      (tramp-compat-funcall 'make-temp-file prefix dir-flag extension))
242 243 244 245 246 247 248 249 250 251 252 253 254
      ;; We use our own implementation, taken from files.el.
      (while
	  (condition-case ()
	      (progn
		(setq result (concat (make-temp-name prefix) extension))
		(if dir-flag
		    (make-directory result)
		  (write-region "" nil result nil 'silent))
		nil)
	    (file-already-exists t))
	;; The file was somehow created by someone else between
	;; `make-temp-name' and `write-region', let's try again.
	nil))
255 256
    result))

257
;; `most-positive-fixnum' does not exist in XEmacs.
258 259
(defsubst tramp-compat-most-positive-fixnum ()
  "Return largest positive integer value (compat function)."
260 261
  (cond
   ((boundp 'most-positive-fixnum) (symbol-value 'most-positive-fixnum))
262
   ;; Default value in XEmacs.
263
   (t 134217727)))
264

265
;; ID-FORMAT does not exists in XEmacs.
266 267 268 269 270
(defun tramp-compat-file-attributes (filename &optional id-format)
  "Like `file-attributes' for Tramp files (compat function)."
  (cond
   ((or (null id-format) (eq id-format 'integer))
    (file-attributes filename))
271 272
   ((tramp-tramp-file-p filename)
    (tramp-file-name-handler 'file-attributes filename id-format))
273
   (t (condition-case nil
274
	  (tramp-compat-funcall 'file-attributes filename id-format)
275
	(wrong-number-of-arguments (file-attributes filename))))))
276 277 278

;; PRESERVE-UID-GID has been introduced with Emacs 23.  It does not
;; hurt to ignore it for other (X)Emacs versions.
279
;; PRESERVE-SELINUX-CONTEXT has been introduced with Emacs 24.
280
(defun tramp-compat-copy-file
281 282
  (filename newname &optional ok-if-already-exists keep-date
	    preserve-uid-gid preserve-selinux-context)
283
  "Like `copy-file' for Tramp files (compat function)."
284 285 286 287 288 289 290 291 292 293 294
  (cond
   (preserve-selinux-context
    (tramp-compat-funcall
     'copy-file filename newname ok-if-already-exists keep-date
     preserve-uid-gid preserve-selinux-context))
   (preserve-uid-gid
    (tramp-compat-funcall
     'copy-file filename newname ok-if-already-exists keep-date
     preserve-uid-gid))
   (t
    (copy-file filename newname ok-if-already-exists keep-date))))
295

296 297 298 299 300 301
;; `copy-directory' is a new function in Emacs 23.2.  Implementation
;; is taken from there.
(defun tramp-compat-copy-directory
  (directory newname &optional keep-time parents)
  "Make a copy of DIRECTORY (compat function)."
  (if (fboundp 'copy-directory)
302
      (tramp-compat-funcall 'copy-directory directory newname keep-time parents)
303

304 305
    ;; If `default-directory' is a remote directory, make sure we find
    ;; its `copy-directory' handler.
306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336
    (let ((handler (or (find-file-name-handler directory 'copy-directory)
		       (find-file-name-handler newname 'copy-directory))))
      (if handler
	  (funcall handler 'copy-directory directory newname keep-time parents)

	;; Compute target name.
	(setq directory (directory-file-name (expand-file-name directory))
	      newname   (directory-file-name (expand-file-name newname)))
	(if (and (file-directory-p newname)
		 (not (string-equal (file-name-nondirectory directory)
				    (file-name-nondirectory newname))))
	    (setq newname
		  (expand-file-name
		   (file-name-nondirectory directory) newname)))
	(if (not (file-directory-p newname)) (make-directory newname parents))

	;; Copy recursively.
	(mapc
	 (lambda (file)
	   (if (file-directory-p file)
	       (tramp-compat-copy-directory file newname keep-time parents)
	     (copy-file file newname t keep-time)))
	 ;; We do not want to delete "." and "..".
	 (directory-files
	  directory 'full "^\\([^.]\\|\\.\\([^.]\\|\\..\\)\\).*"))

	;; Set directory attributes.
	(set-file-modes newname (file-modes directory))
	(if keep-time
	    (set-file-times newname (nth 5 (file-attributes directory))))))))

337 338 339
;; FORCE has been introduced with Emacs 24.1.
(defun tramp-compat-delete-file (filename &optional force)
  "Like `delete-file' for Tramp files (compat function)."
340 341 342
  (if (null force)
      (delete-file filename)
    (condition-case nil
343
	(tramp-compat-funcall 'delete-file filename force)
344 345 346 347 348 349 350 351 352 353
      ;; This Emacs version does not support the FORCE flag.  Setting
      ;; `delete-by-moving-to-trash' shall give us the same effect.
      (wrong-number-of-arguments
       (let ((delete-by-moving-to-trash
	      (cond
	       ((null force) t)
	       ((boundp 'delete-by-moving-to-trash)
		(symbol-value 'delete-by-moving-to-trash))
	       (t nil))))
	 (delete-file filename))))))
354

355 356 357
;; RECURSIVE has been introduced with Emacs 23.2.
(defun tramp-compat-delete-directory (directory &optional recursive)
  "Like `delete-directory' for Tramp files (compat function)."
358 359 360
  (if (null recursive)
      (delete-directory directory)
    (condition-case nil
361
	(tramp-compat-funcall 'delete-directory directory recursive)
362 363
      ;; This Emacs version does not support the RECURSIVE flag.  We
      ;; use the implementation from Emacs 23.2.
364
      (wrong-number-of-arguments
365 366 367 368 369 370 371 372 373 374 375 376
       (setq directory (directory-file-name (expand-file-name directory)))
       (if (not (file-symlink-p directory))
	   (mapc (lambda (file)
		   (if (eq t (car (file-attributes file)))
		       (tramp-compat-delete-directory file recursive)
		     (delete-file file)))
		 (directory-files
		  directory 'full "^\\([^.]\\|\\.\\([^.]\\|\\..\\)\\).*")))
       (delete-directory directory)))))

;; `number-sequence' does not exist in XEmacs.  Implementation is
;; taken from Emacs 23.
377 378 379
(defun tramp-compat-number-sequence (from &optional to inc)
  "Return a sequence of numbers from FROM to TO as a list (compat function)."
  (if (or (subrp 'number-sequence) (symbol-file 'number-sequence))
380
      (tramp-compat-funcall 'number-sequence from to inc)
381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396
    (if (or (not to) (= from to))
	(list from)
      (or inc (setq inc 1))
      (when (zerop inc) (error "The increment can not be zero"))
      (let (seq (n 0) (next from))
	(if (> inc 0)
	    (while (<= next to)
	      (setq seq (cons next seq)
		    n (1+ n)
		    next (+ from (* n inc))))
	  (while (>= next to)
	    (setq seq (cons next seq)
		  n (1+ n)
		  next (+ from (* n inc)))))
	(nreverse seq)))))

397 398 399 400 401 402 403 404 405 406 407 408 409
(defun tramp-compat-split-string (string pattern)
  "Like `split-string' but omit empty strings.
In Emacs, (split-string \"/foo/bar\" \"/\") returns (\"foo\" \"bar\").
This is, the first, empty, element is omitted.  In XEmacs, the first
element is not omitted."
  (delete "" (split-string string pattern)))

(defun tramp-compat-process-running-p (process-name)
  "Returns `t' if system process PROCESS-NAME is running for `user-login-name'."
  (when (stringp process-name)
    (cond
     ;; GNU Emacs 22 on w32.
     ((fboundp 'w32-window-exists-p)
410
      (tramp-compat-funcall 'w32-window-exists-p process-name process-name))
411 412 413 414

     ;; GNU Emacs 23.
     ((and (fboundp 'list-system-processes) (fboundp 'process-attributes))
      (let (result)
415 416
	(dolist (pid (tramp-compat-funcall 'list-system-processes) result)
	  (let ((attributes (tramp-compat-funcall 'process-attributes pid)))
417 418 419 420 421 422 423 424 425
	    (when (and (string-equal
                        (cdr (assoc 'user attributes)) (user-login-name))
                       (let ((comm (cdr (assoc 'comm attributes))))
                         ;; The returned command name could be truncated
                         ;; to 15 characters.  Therefore, we cannot check
                         ;; for `string-equal'.
                         (and comm (string-match
                                    (concat "^" (regexp-quote comm))
                                    process-name))))
426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445
	      (setq result t))))))

     ;; Fallback, if there is no Lisp support yet.
     (t (let ((default-directory
		(if (file-remote-p default-directory)
		    (tramp-compat-temporary-file-directory)
		  default-directory))
	      (unix95 (getenv "UNIX95"))
	      result)
	  (setenv "UNIX95" "1")
	  (when (member
		 (user-login-name)
		 (tramp-compat-split-string
		  (shell-command-to-string
		   (format "ps -C %s -o user=" process-name))
		  "[ \f\t\n\r\v]+"))
	    (setq result t))
	  (setenv "UNIX95" unix95)
	  result)))))

446 447 448 449
(provide 'tramp-compat)

;;; TODO:

Miles Bader's avatar
Miles Bader committed
450
;; arch-tag: 0e724b18-6699-4f87-ad96-640b272e5c85
451
;;; tramp-compat.el ends here