tramp-compat.el 17.8 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

;; Author: Michael Albinus <michael.albinus@gmx.de>
;; Keywords: comm, processes
7
;; Package: tramp
8 9 10

;; This file is part of GNU Emacs.

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 14
;; the Free Software Foundation, either version 3 of the License, or
;; (at your option) any later version.
15 16 17 18 19 20 21

;; 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
22
;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
23 24 25

;;; Commentary:

26 27 28
;; 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+.
29 30 31

;;; Code:

32
(require 'tramp-loaddefs)
33

34
(eval-when-compile
35 36

  ;; Pacify byte-compiler.
37 38 39 40
  (require 'cl))

(eval-and-compile

41
  (require 'custom)
42

43 44 45 46
  ;; Load the appropriate timer package.
  (if (featurep 'xemacs)
      (require 'timer-funcs)
    (require 'timer))
47

48 49 50 51 52
  ;; We check whether `start-file-process' is bound.
  (unless (fboundp 'start-file-process)

    ;; tramp-util offers integration into other (X)Emacs packages like
    ;; compile.el, gud.el etc.  Not necessary in Emacs 23.
53
    (eval-after-load "tramp"
54
      '(require 'tramp-util))
55 56 57 58 59 60

    ;; 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"
61
	'(require 'tramp-vc))))
62

63 64 65 66 67 68 69 70
  ;; 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.
71
  (unless (boundp 'last-coding-system-used)
72
    (defvar last-coding-system-used nil))
73

74 75 76
  ;; `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.
77 78
  (unless (boundp 'byte-compile-not-obsolete-var)
    (defvar byte-compile-not-obsolete-var nil))
79
  (setq byte-compile-not-obsolete-var 'directory-sep-char)
80 81 82 83
  ;; 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))
84

85
  ;; `with-temp-message' does not exists in XEmacs.
86 87
  (condition-case nil
      (with-temp-message (current-message) nil)
88
    (error (defmacro with-temp-message (message &rest body) `(progn ,@body))))
89

90 91 92 93 94 95 96 97 98
  ;; 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)))))

99
  ;; `set-buffer-multibyte' comes from Emacs Leim.
100
  (unless (fboundp 'set-buffer-multibyte)
101
    (defalias 'set-buffer-multibyte 'ignore))
102

103
  ;; `font-lock-add-keywords' does not exist in XEmacs.
104
  (unless (fboundp 'font-lock-add-keywords)
105 106
    (defalias 'font-lock-add-keywords 'ignore))

107 108 109 110
  ;; The following functions cannot be aliases of the corresponding
  ;; `tramp-handle-*' functions, because this would bypass the locking
  ;; mechanism.

111 112 113 114 115
  ;; `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)
116 117 118 119 120
    (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)))))
121

122
  ;; `process-file' does not exist in XEmacs.
123
  (unless (fboundp 'process-file)
124 125 126 127 128 129
    (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)))))
130 131 132

  ;; `start-file-process' is new in Emacs 23.
  (unless (fboundp 'start-file-process)
133 134 135 136 137 138
    (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)))))
139 140 141

  ;; `set-file-times' is also new in Emacs 23.
  (unless (fboundp 'set-file-times)
142 143 144 145
    (defalias 'set-file-times
      (lambda (filename &optional time)
	(when (tramp-tramp-file-p filename)
	  (tramp-file-name-handler
146 147 148 149 150 151 152 153 154 155
	   '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.
156 157 158
  (unless (or (featurep 'xemacs)
	      ;; `featurep' has only one argument in XEmacs.
	      (funcall 'featurep 'files 'remote-wildcards))
159 160 161 162 163 164 165 166
    (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
167 168
		   "[[*?]" (tramp-compat-funcall
			    'file-remote-p name 'localname))))
169 170 171 172 173 174 175 176 177
	    (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)))))
178

179 180 181 182 183 184
(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)
185 186
    (tramp-compat-funcall 'line-beginning-position))
   ((fboundp 'point-at-bol) (tramp-compat-funcall 'point-at-bol))
187 188
   (t (save-excursion (beginning-of-line) (point)))))

189 190 191 192 193
(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
194 195
   ((fboundp 'line-end-position) (tramp-compat-funcall 'line-end-position))
   ((fboundp 'point-at-eol) (tramp-compat-funcall 'point-at-eol))
196 197 198 199 200 201 202
   (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
203
   ((boundp 'temporary-file-directory) (symbol-value 'temporary-file-directory))
204
   ((fboundp 'temp-directory) (tramp-compat-funcall 'temp-directory))
205 206 207 208 209 210 211 212 213 214 215
   ((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"))))

216 217 218
;; `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.
219
(defsubst tramp-compat-make-temp-file (filename &optional dir-flag)
220 221
  "Create a temporary file (compat function).
Add the extension of FILENAME, if existing."
222 223 224 225 226 227
  (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)
228
    (condition-case nil
229
	(setq result
230
	      (tramp-compat-funcall 'make-temp-file prefix dir-flag extension))
231 232 233 234 235 236 237 238 239 240 241 242 243 244
      (error
       ;; 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)))
245 246
    result))

247
;; `most-positive-fixnum' does not exist in XEmacs.
248 249
(defsubst tramp-compat-most-positive-fixnum ()
  "Return largest positive integer value (compat function)."
250 251
  (cond
   ((boundp 'most-positive-fixnum) (symbol-value 'most-positive-fixnum))
252
   ;; Default value in XEmacs.
253
   (t 134217727)))
254

255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272
(defun tramp-compat-decimal-to-octal (i)
  "Return a string consisting of the octal digits of I.
Not actually used.  Use `(format \"%o\" i)' instead?"
  (cond ((< i 0) (error "Cannot convert negative number to octal"))
        ((not (integerp i)) (error "Cannot convert non-integer to octal"))
        ((zerop i) "0")
        (t (concat (tramp-compat-decimal-to-octal (/ i 8))
                   (number-to-string (% i 8))))))

;; Kudos to Gerd Moellmann for this suggestion.
(defun tramp-compat-octal-to-decimal (ostr)
  "Given a string of octal digits, return a decimal number."
  (let ((x (or ostr "")))
    ;; `save-match' is in `tramp-mode-string-to-int' which calls this.
    (unless (string-match "\\`[0-7]*\\'" x)
      (error "Non-octal junk in string `%s'" x))
    (string-to-number ostr 8)))

273
;; ID-FORMAT does not exists in XEmacs.
274 275 276 277 278
(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))
279 280
   ((tramp-tramp-file-p filename)
    (tramp-file-name-handler 'file-attributes filename id-format))
281
   (t (condition-case nil
282
	  (tramp-compat-funcall 'file-attributes filename id-format)
283
	(wrong-number-of-arguments (file-attributes filename))))))
284 285 286

;; PRESERVE-UID-GID has been introduced with Emacs 23.  It does not
;; hurt to ignore it for other (X)Emacs versions.
287
;; PRESERVE-SELINUX-CONTEXT has been introduced with Emacs 24.
288
(defun tramp-compat-copy-file
289 290
  (filename newname &optional ok-if-already-exists keep-date
	    preserve-uid-gid preserve-selinux-context)
291
  "Like `copy-file' for Tramp files (compat function)."
292 293 294 295 296 297 298 299 300 301 302
  (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))))
303

304 305 306 307 308 309
;; `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)
310
      (tramp-compat-funcall 'copy-directory directory newname keep-time parents)
311

312 313
    ;; If `default-directory' is a remote directory, make sure we find
    ;; its `copy-directory' handler.
314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344
    (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))))))))

345 346
;; TRASH has been introduced with Emacs 24.1.
(defun tramp-compat-delete-file (filename &optional trash)
347
  "Like `delete-file' for Tramp files (compat function)."
348 349 350 351 352 353
  (condition-case nil
      (tramp-compat-funcall 'delete-file filename trash)
    ;; This Emacs version does not support the TRASH flag.
    (wrong-number-of-arguments
     (let ((delete-by-moving-to-trash
	    (and (boundp 'delete-by-moving-to-trash)
354
		 (symbol-value 'delete-by-moving-to-trash)
355 356
		 trash)))
       (delete-file filename)))))
357

358 359 360
;; RECURSIVE has been introduced with Emacs 23.2.
(defun tramp-compat-delete-directory (directory &optional recursive)
  "Like `delete-directory' for Tramp files (compat function)."
361 362 363
  (if (null recursive)
      (delete-directory directory)
    (condition-case nil
364
	(tramp-compat-funcall 'delete-directory directory recursive)
365 366
      ;; This Emacs version does not support the RECURSIVE flag.  We
      ;; use the implementation from Emacs 23.2.
367
      (wrong-number-of-arguments
368 369 370 371 372 373 374 375 376 377 378 379
       (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.
380 381 382
(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))
383
      (tramp-compat-funcall 'number-sequence from to inc)
384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399
    (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)))))

400 401 402 403 404 405 406
(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)))

407 408 409 410 411 412 413 414 415 416 417 418 419 420
(defun tramp-compat-call-process
  (program &optional infile destination display &rest args)
  "Calls `call-process' on the local host.
This is needed because for some Emacs flavors Tramp has
defadviced `call-process' to behave like `process-file'.  The
Lisp error raised when PROGRAM is nil is trapped also, returning 1."
  (let ((default-directory
	  (if (file-remote-p default-directory)
	      (tramp-compat-temporary-file-directory)
	    default-directory)))
    (if (executable-find program)
	(apply 'call-process program infile destination display args)
      1)))

421 422 423 424 425 426
(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)
427
      (tramp-compat-funcall 'w32-window-exists-p process-name process-name))
428 429 430 431

     ;; GNU Emacs 23.
     ((and (fboundp 'list-system-processes) (fboundp 'process-attributes))
      (let (result)
432 433
	(dolist (pid (tramp-compat-funcall 'list-system-processes) result)
	  (let ((attributes (tramp-compat-funcall 'process-attributes pid)))
434 435 436 437 438 439 440 441 442
	    (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))))
443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462
	      (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)))))

463 464 465 466
(add-hook 'tramp-unload-hook
	  (lambda ()
	    (unload-feature 'tramp-compat 'force)))

467 468 469 470
(provide 'tramp-compat)

;;; TODO:

Miles Bader's avatar
Miles Bader committed
471
;; arch-tag: 0e724b18-6699-4f87-ad96-640b272e5c85
472
;;; tramp-compat.el ends here