1 ;;; url-handlers.el --- file-name-handler stuff for URL loading
3 ;; Copyright (C) 1996-1999, 2004-2014 Free Software Foundation, Inc.
5 ;; Keywords: comm, data, processes, hypermedia
7 ;; This file is part of GNU Emacs.
9 ;; GNU Emacs is free software: you can redistribute it and/or modify
10 ;; it under the terms of the GNU General Public License as published by
11 ;; the Free Software Foundation, either version 3 of the License, or
12 ;; (at your option) any later version.
14 ;; GNU Emacs is distributed in the hope that it will be useful,
15 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
16 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 ;; GNU General Public License for more details.
19 ;; You should have received a copy of the GNU General Public License
20 ;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
28 ;; (require 'url-util)
29 (eval-when-compile (require 'mm-decode
))
31 ;; The following are autoloaded instead of `require'd to avoid eagerly
32 ;; loading all of URL when turning on url-handler-mode in the .emacs.
33 (autoload 'url-expand-file-name
"url-expand" "Convert url to a fully specified url, and canonicalize it.")
34 (autoload 'mm-dissect-buffer
"mm-decode" "Dissect the current buffer and return a list of MIME handles.")
35 (autoload 'url-scheme-get-property
"url-methods" "Get property of a URL SCHEME.")
36 (autoload 'url-http-parse-response
"url-http" "Parse just the response code.")
38 ;; Always used after mm-dissect-buffer and defined in the same file.
39 (declare-function mm-save-part-to-file
"mm-decode" (handle file
))
40 (declare-function mm-destroy-parts
"mm-decode" (handles))
41 ;; mm-decode loads mm-bodies.
42 (declare-function mm-decode-string
"mm-bodies" (string charset
))
43 ;; mm-decode loads mail-parse.
44 (declare-function mail-content-type-get
"mail-parse" (ct attribute
))
46 ;; Implementation status
47 ;; ---------------------
49 ;; ------------------------------------------------------------
50 ;; add-name-to-file Needs DAV Bindings
51 ;; copy-file Broken (assumes 1st item is URL)
52 ;; delete-directory Finished (DAV)
53 ;; delete-file Finished (DAV)
54 ;; diff-latest-backup-file
55 ;; directory-file-name unnecessary (what about VMS)?
56 ;; directory-files Finished (DAV)
58 ;; dired-compress-file
60 ;; expand-file-name Finished
61 ;; file-accessible-directory-p
62 ;; file-attributes Finished, better with DAV
63 ;; file-directory-p Needs DAV, finished
64 ;; file-executable-p Finished
65 ;; file-exists-p Finished
68 ;; file-name-all-completions Finished (DAV)
69 ;; file-name-as-directory
70 ;; file-name-completion Finished (DAV)
71 ;; file-name-directory
72 ;; file-name-nondirectory
73 ;; file-name-sans-versions why?
74 ;; file-newer-than-file-p
75 ;; file-ownership-preserved-p No way to know
76 ;; file-readable-p Finished
77 ;; file-regular-p !directory_p
78 ;; file-remote-p Finished
79 ;; file-symlink-p Needs DAV bindings
80 ;; file-truename Needs DAV bindings
81 ;; file-writable-p Check for LOCK?
82 ;; find-backup-file-name why?
83 ;; get-file-buffer why?
84 ;; insert-directory Use DAV
85 ;; insert-file-contents Finished
87 ;; make-directory Finished (DAV)
88 ;; make-symbolic-link Needs DAV bindings
89 ;; rename-file Finished (DAV)
90 ;; set-file-modes Use mod_dav specific executable flag?
91 ;; set-visited-file-modtime Impossible?
92 ;; shell-command Impossible?
93 ;; unhandled-file-name-directory
94 ;; vc-registered Finished (DAV)
95 ;; verify-visited-file-modtime
98 (defvar url-handler-regexp
) ; defined below to avoid recursive load (revno:108572)
101 (define-minor-mode url-handler-mode
102 "Toggle using `url' library for URL filenames (URL Handler mode).
103 With a prefix argument ARG, enable URL Handler mode if ARG is
104 positive, and disable it otherwise. If called from Lisp, enable
105 the mode if ARG is omitted or nil."
106 :global t
:group
'url
107 ;; Remove old entry, if any.
108 (setq file-name-handler-alist
109 (delq (rassq 'url-file-handler file-name-handler-alist
)
110 file-name-handler-alist
))
112 (push (cons url-handler-regexp
'url-file-handler
)
113 file-name-handler-alist
)))
115 (defcustom url-handler-regexp
"\\`\\(https?\\|ftp\\|file\\|nfs\\|ssh\\|scp\\|rsync\\|telnet\\)://"
116 "Regular expression for URLs handled by `url-handler-mode'.
117 When URL Handler mode is enabled, this regular expression is
118 added to `file-name-handler-alist'.
120 Some valid URL protocols just do not make sense to visit
121 interactively \(about, data, info, irc, mailto, etc\). This
122 regular expression avoids conflicts with local files that look
123 like URLs \(Gnus is particularly bad at this\)."
127 :set
(lambda (symbol value
)
128 (let ((enable url-handler-mode
))
130 (set-default symbol value
)
132 (url-handler-mode)))))
134 (defun url-run-real-handler (operation args
)
135 (let ((inhibit-file-name-handlers (cons 'url-file-handler
136 (if (eq operation inhibit-file-name-operation
)
137 inhibit-file-name-handlers
)))
138 (inhibit-file-name-operation operation
))
139 (apply operation args
)))
142 (defun url-file-handler (operation &rest args
)
143 "Function called from the `file-name-handler-alist' routines.
144 OPERATION is what needs to be done (`file-exists-p', etc). ARGS are
145 the arguments that would have been passed to OPERATION."
146 ;; Check, whether there are arguments we want pass to Tramp.
148 (dolist (url (cons default-directory args
))
150 (url-type (url-generic-parse-url (and (stringp url
) url
)))
153 (apply 'url-tramp-file-handler operation args
)
154 ;; Otherwise, let's do the job.
155 (let ((fn (get operation
'url-file-handlers
))
158 (if (and (not fn
) (intern-soft (format "url-%s" operation
))
159 (fboundp (intern-soft (format "url-%s" operation
))))
160 (error "Missing URL handler mapping for %s" operation
))
163 val
(save-match-data (apply fn args
)))
165 val
(url-run-real-handler operation args
)))
166 (url-debug 'handlers
"%s %S%S => %S" (if hooked
"Hooked" "Real")
170 (defun url-file-handler-identity (&rest args
)
174 ;; These are operations that we can fully support
175 (put 'file-readable-p
'url-file-handlers
'url-file-exists-p
)
176 (put 'substitute-in-file-name
'url-file-handlers
'url-file-handler-identity
)
177 (put 'file-name-absolute-p
'url-file-handlers
(lambda (&rest ignored
) t
))
178 (put 'expand-file-name
'url-file-handlers
'url-handler-expand-file-name
)
179 (put 'directory-file-name
'url-file-handlers
'url-handler-directory-file-name
)
180 (put 'unhandled-file-name-directory
'url-file-handlers
'url-handler-unhandled-file-name-directory
)
181 (put 'file-remote-p
'url-file-handlers
'url-handler-file-remote-p
)
182 ;; (put 'file-name-as-directory 'url-file-handlers 'url-handler-file-name-as-directory)
184 ;; These are operations that we do not support yet (DAV!!!)
185 (put 'file-writable-p
'url-file-handlers
'ignore
)
186 (put 'file-symlink-p
'url-file-handlers
'ignore
)
187 ;; Just like for ange-ftp: let's not waste time trying to look for RCS/foo,v
188 ;; files and such since we can't do anything clever with them anyway.
189 (put 'vc-registered
'url-file-handlers
'ignore
)
191 (defun url-handler-expand-file-name (file &optional base
)
192 ;; When we see "/foo/bar" in a file whose working dir is "http://bla/bla",
193 ;; there are two interpretations possible: either it's a local "/foo/bar"
194 ;; or it's "http:/bla/foo/bar". When working with URLs, the second
195 ;; interpretation is the right one, but when working with Emacs file
196 ;; names, the first is preferred.
197 (if (file-name-absolute-p file
)
198 (expand-file-name file
"/")
199 (url-expand-file-name file base
)))
201 ;; directory-file-name and file-name-as-directory are kind of hard to
202 ;; implement really right for URLs since URLs can have repeated / chars.
203 ;; We'd want the following behavior:
204 ;; idempotence: (d-f-n (d-f-n X) == (d-f-n X)
205 ;; idempotence: (f-n-a-d (f-n-a-d X) == (f-n-a-d X)
206 ;; reversible: (d-f-n (f-n-a-d (d-f-n X))) == (d-f-n X)
207 ;; reversible: (f-n-a-d (d-f-n (f-n-a-d X))) == (f-n-a-d X)
208 (defun url-handler-directory-file-name (dir)
209 ;; When there's more than a single /, just don't touch the slashes at all.
210 (if (string-match "//\\'" dir
) dir
211 (url-run-real-handler 'directory-file-name
(list dir
))))
213 (defun url-handler-unhandled-file-name-directory (filename)
214 (let ((url (url-generic-parse-url filename
)))
215 (if (equal (url-type url
) "file")
216 ;; `file' URLs are actually local. The filename part may be ""
217 ;; which really stands for "/".
218 ;; FIXME: maybe we should check that the host part is "" or "localhost"
219 ;; or some name that represents the local host?
220 (or (file-name-directory (url-filename url
)) "/")
221 ;; All other URLs are not expected to be directly accessible from
225 (defun url-handler-file-remote-p (filename &optional identification connected
)
226 (let ((url (url-generic-parse-url filename
)))
227 (if (and (url-type url
) (not (equal (url-type url
) "file")))
228 ;; Maybe we can find a suitable check for CONNECTED. For now,
231 ((eq identification
'method
) (url-type url
))
232 ((eq identification
'user
) (url-user url
))
233 ((eq identification
'host
) (url-host url
))
234 ((eq identification
'localname
) (url-filename url
))
236 (url-parse-make-urlobj (url-type url
) (url-user url
) nil
237 (url-host url
) (url-port url
)))))
238 ;; If there is no URL type, or it is a "file://" URL, the
239 ;; filename is expected to be non remote. A more subtle check
240 ;; for "file://" URLs could be applied, as said in
241 ;; `url-handler-unhandled-file-name-directory'.
244 ;; The actual implementation
246 (defun url-copy-file (url newname
&optional ok-if-already-exists
247 keep-time preserve-uid-gid
)
248 "Copy URL to NEWNAME. Both args must be strings.
249 Signals a `file-already-exists' error if file NEWNAME already exists,
250 unless a third argument OK-IF-ALREADY-EXISTS is supplied and non-nil.
251 A number as third arg means request confirmation if NEWNAME already exists.
252 This is what happens in interactive use with M-x.
253 Fourth arg KEEP-TIME non-nil means give the new file the same
254 last-modified time as the old one. (This works on only some systems.)
255 Fifth arg PRESERVE-UID-GID is ignored.
256 A prefix arg makes KEEP-TIME non-nil."
257 (if (and (file-exists-p newname
)
258 (not ok-if-already-exists
))
259 (error "Opening output file: File already exists, %s" newname
))
260 (let ((buffer (url-retrieve-synchronously url
))
263 (error "Opening input file: No such file or directory, %s" url
))
264 (with-current-buffer buffer
265 (setq handle
(mm-dissect-buffer t
)))
266 (mm-save-part-to-file handle newname
)
268 (mm-destroy-parts handle
)))
269 (put 'copy-file
'url-file-handlers
'url-copy-file
)
272 (defun url-file-local-copy (url &rest ignored
)
273 "Copy URL into a temporary file on this machine.
274 Returns the name of the local copy, or nil, if FILE is directly
276 (let ((filename (make-temp-file "url")))
277 (url-copy-file url filename
'ok-if-already-exists
)
279 (put 'file-local-copy
'url-file-handlers
'url-file-local-copy
)
281 (defun url-insert (buffer &optional beg end
)
282 "Insert the body of a URL object.
283 BUFFER should be a complete URL buffer as returned by `url-retrieve'.
284 If the headers specify a coding-system, it is applied to the body before it is inserted.
285 Returns a list of the form (SIZE CHARSET), where SIZE is the size in bytes
286 of the inserted text and CHARSET is the charset that was specified in the header,
287 or nil if none was found.
288 BEG and END can be used to only insert a subpart of the body.
289 They count bytes from the beginning of the body."
290 (let* ((handle (with-current-buffer buffer
(mm-dissect-buffer t
)))
291 (data (with-current-buffer (mm-handle-buffer handle
)
293 (buffer-substring (+ (point-min) beg
)
294 (if end
(+ (point-min) end
) (point-max)))
296 (charset (mail-content-type-get (mm-handle-type handle
)
298 (mm-destroy-parts handle
)
300 (insert (mm-decode-string data
(mm-charset-to-coding-system charset
)))
302 (list (length data
) charset
)))
305 (defun url-insert-file-contents (url &optional visit beg end replace
)
306 (let ((buffer (url-retrieve-synchronously url
)))
307 (unless buffer
(signal 'file-error
(list url
"No Data")))
308 (with-current-buffer buffer
309 (let ((response (url-http-parse-response)))
310 (if (and (>= response
200) (< response
300))
311 (goto-char (point-min))
312 (let ((desc (buffer-substring-no-properties (1+ (point))
313 (line-end-position))))
315 (signal 'file-error
(list url desc
))))))
316 (if visit
(setq buffer-file-name url
))
318 (let* ((start (point))
319 (size-and-charset (url-insert buffer beg end
)))
322 (delete-region (point-min) start
)
323 (delete-region (point) (point-max)))
324 (unless (cadr size-and-charset
)
325 ;; If the headers don't specify any particular charset, use the
326 ;; usual heuristic/rules that we apply to files.
327 (decode-coding-inserted-region start
(point) url visit beg end replace
))
328 (list url
(car size-and-charset
))))))
329 (put 'insert-file-contents
'url-file-handlers
'url-insert-file-contents
)
331 (defun url-file-name-completion (url directory
&optional predicate
)
332 ;; Even if it's not implemented, it's not an error to ask for completion,
333 ;; in case it's available (bug#14806).
334 ;; (error "Unimplemented")
336 (put 'file-name-completion
'url-file-handlers
'url-file-name-completion
)
338 (defun url-file-name-all-completions (file directory
)
339 ;; Even if it's not implemented, it's not an error to ask for completion,
340 ;; in case it's available (bug#14806).
341 ;; (error "Unimplemented")
343 (put 'file-name-all-completions
344 'url-file-handlers
'url-file-name-all-completions
)
346 ;; All other handlers map onto their respective backends.
347 (defmacro url-handlers-create-wrapper
(method args
)
349 (defun ,(intern (format "url-%s" method
)) ,args
350 ,(format "URL file-name-handler wrapper for `%s' call.\n---\n%s" method
351 (or (documentation method t
) "No original documentation."))
352 (setq url
(url-generic-parse-url url
))
354 (funcall (url-scheme-get-property (url-type url
) (quote ,method
))
355 ,@(remove '&rest
(remove '&optional args
)))))
356 (unless (get ',method
'url-file-handlers
)
357 (put ',method
'url-file-handlers
',(intern (format "url-%s" method
))))))
359 (url-handlers-create-wrapper file-exists-p
(url))
360 (url-handlers-create-wrapper file-attributes
(url &optional id-format
))
361 (url-handlers-create-wrapper file-symlink-p
(url))
362 (url-handlers-create-wrapper file-writable-p
(url))
363 (url-handlers-create-wrapper file-directory-p
(url))
364 (url-handlers-create-wrapper file-executable-p
(url))
365 (url-handlers-create-wrapper directory-files
(url &optional full match nosort
))
366 (url-handlers-create-wrapper file-truename
(url &optional counter prev-dirs
))
368 (add-hook 'find-file-hook
'url-handlers-set-buffer-mode
)
370 (defun url-handlers-set-buffer-mode ()
371 "Set correct modes for the current buffer if visiting a remote file."
372 (and (stringp buffer-file-name
)
373 (string-match url-handler-regexp buffer-file-name
)
376 (provide 'url-handlers
)
378 ;;; url-handlers.el ends here