lisp/url/url-file.el

   1 ;;; url-file.el --- File retrieval code
   2
   3 ;; Copyright (C) 1996, 1997, 1998, 1999, 2004,
   4 ;;   2005, 2006, 2007, 2008 Free Software Foundation, Inc.
   5
   6 ;; Keywords: comm, data, processes
   7
   8 ;; This file is part of GNU Emacs.
   9 ;;
  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 ;; the Free Software Foundation, either version 3 of the License, or
  13 ;; (at your option) any later version.
  14
  15 ;; GNU Emacs is distributed in the hope that it will be useful,
  16 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 ;; GNU General Public License for more details.
  19
  20 ;; 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 ;;; Commentary:
  24
  25 ;;; Code:
  26
  27 (eval-when-compile (require 'cl))
  28 (require 'mailcap)
  29 (require 'url-vars)
  30 (require 'url-parse)
  31 (require 'url-dired)
  32
  33 (defconst url-file-default-port 21 "Default FTP port.")
  34 (defconst url-file-asynchronous-p t "FTP transfers are asynchronous.")
  35 (defalias 'url-file-expand-file-name 'url-default-expander)
  36
  37 (defun url-file-find-possibly-compressed-file (fname &rest args)
  38   "Find the exact file referenced by `fname'.
  39 This tries the common compression extensions, because things like
  40 ange-ftp and efs are not quite smart enough to realize when a server
  41 can do automatic decompression for them, and won't find 'foo' if
  42 'foo.gz' exists, even though the ftp server would happily serve it up
  43 to them."
  44   (let ((scratch nil)
  45         (compressed-extensions '("" ".gz" ".z" ".Z" ".bz2"))
  46         (found nil))
  47     (while (and compressed-extensions (not found))
  48       (if (file-exists-p (setq scratch (concat fname (pop compressed-extensions))))
  49           (setq found scratch)))
  50     found))
  51
  52 (defun url-file-host-is-local-p (host)
  53   "Return t if HOST references our local machine."
  54   (let ((case-fold-search t))
  55     (or
  56      (null host)
  57      (string= "" host)
  58      (equal (downcase host) (downcase (system-name)))
  59      (and (string-match "^localhost$" host) t)
  60      (and (not (string-match (regexp-quote ".") host))
  61           (equal (downcase host) (if (string-match (regexp-quote ".")
  62                                                    (system-name))
  63                                      (substring (system-name) 0
  64                                                 (match-beginning 0))
  65                                    (system-name)))))))
  66
  67 (defun url-file-asynch-callback (x y name buff func args &optional efs)
  68   (if (not (featurep 'ange-ftp))
  69       ;; EFS passes us an extra argument
  70       (setq name buff
  71             buff func
  72             func args
  73             args efs))
  74   (let ((size (nth 7 (file-attributes name))))
  75     (with-current-buffer buff
  76       (goto-char (point-max))
  77       (if (/= -1 size)
  78           (insert (format "Content-length: %d\n" size)))
  79       (insert "\n")
  80       (insert-file-contents-literally name)
  81       (if (not (url-file-host-is-local-p (url-host url-current-object)))
  82           (condition-case ()
  83               (delete-file name)
  84             (error nil)))
  85       (apply func args))))
  86
  87 (declare-function ange-ftp-set-passwd "ange-ftp" (host user passwd))
  88 (declare-function ange-ftp-copy-file-internal "ange-ftp"
  89                   (filename newname ok-if-already-exists
  90                             keep-date &optional msg cont nowait))
  91 (declare-function url-generate-unique-filename "url-util" (&optional fmt))
  92
  93 (defun url-file-build-filename (url)
  94   (if (not (vectorp url))
  95       (setq url (url-generic-parse-url url)))
  96   (let* ((user (url-user url))
  97          (pass (url-password url))
  98          (port (url-port url))
  99          (host (url-host url))
 100          (site (if (and port (/= port 21))
 101                    (if (featurep 'ange-ftp)
 102                        (format "%s %d" host port)
 103                      ;; This works in Emacs 21's ange-ftp too.
 104                      (format "%s#%d" host port))
 105                  host))
 106          (file (url-unhex-string (url-filename url)))
 107          (filename (if (or user (not (url-file-host-is-local-p host)))
 108                        (concat "/" (or user "anonymous") "@" site ":" file)
 109                      (if (and (memq system-type
 110                                     '(emx ms-dos windows-nt ms-windows))
 111                               (string-match "^/[a-zA-Z]:/" file))
 112                          (substring file 1)
 113                        file)))
 114          pos-index)
 115
 116     (and user pass
 117          (cond
 118           ((featurep 'ange-ftp)
 119            (ange-ftp-set-passwd host user pass))
 120           ((when (featurep 'xemacs)
 121              (or (featurep 'efs) (featurep 'efs-auto)
 122                  (efs-set-passwd host user pass))))
 123           (t
 124            nil)))
 125
 126     ;; This makes sure that directories have a trailing directory
 127     ;; separator on them so URL expansion works right.
 128     ;;
 129     ;; FIXME?  What happens if the remote system doesn't use our local
 130     ;; directory-sep-char as its separator?  Would it be safer to just
 131     ;; use '/' unconditionally and rely on the FTP server to
 132     ;; straighten it out for us?
 133     ;; (if (and (file-directory-p filename)
 134     ;;          (not (string-match (format "%c$" directory-sep-char) filename)))
 135     ;;     (setf (url-filename url)
 136     ;;           (format "%s%c" filename directory-sep-char)))
 137     (if (and (file-directory-p filename)
 138              (not (string-match "/\\'" filename)))
 139         (setf (url-filename url) (format "%s/" filename)))
 140
 141
 142     ;; If it is a directory, look for an index file first.
 143     (if (and (file-directory-p filename)
 144              url-directory-index-file
 145              (setq pos-index (expand-file-name url-directory-index-file filename))
 146              (file-exists-p pos-index)
 147              (file-readable-p pos-index))
 148         (setq filename pos-index))
 149
 150     ;; Find the (possibly compressed) file
 151     (setq filename (url-file-find-possibly-compressed-file filename))
 152     filename))
 153
 154 ;;;###autoload
 155 (defun url-file (url callback cbargs)
 156   "Handle file: and ftp: URLs."
 157   (let* ((buffer nil)
 158          (uncompressed-filename nil)
 159          (content-type nil)
 160          (content-encoding nil)
 161          (coding-system-for-read 'binary))
 162
 163     (setq filename (url-file-build-filename url))
 164
 165     (if (not filename)
 166         (error "File does not exist: %s" (url-recreate-url url)))
 167
 168     ;; Need to figure out the content-type from the real extension,
 169     ;; not the compressed one.
 170     (setq uncompressed-filename (if (string-match "\\.\\(gz\\|Z\\|z\\)$" filename)
 171                                     (substring filename 0 (match-beginning 0))
 172                                   filename))
 173     (setq content-type (mailcap-extension-to-mime
 174                         (url-file-extension uncompressed-filename))
 175           content-encoding (case (intern (url-file-extension filename))
 176                              ((\.z \.gz) "gzip")
 177                              (\.Z "compress")
 178                              (\.uue "x-uuencoded")
 179                              (\.hqx "x-hqx")
 180                              (\.bz2 "x-bzip2")
 181                              (otherwise nil)))
 182
 183     (if (file-directory-p filename)
 184         ;; A directory is done the same whether we are local or remote
 185         (url-find-file-dired filename)
 186       (with-current-buffer
 187           (setq buffer (generate-new-buffer " *url-file*"))
 188         (mm-disable-multibyte)
 189         (setq url-current-object url)
 190         (insert "Content-type: " (or content-type "application/octet-stream") "\n")
 191         (if content-encoding
 192             (insert "Content-transfer-encoding: " content-encoding "\n"))
 193         (if (url-file-host-is-local-p (url-host url))
 194               ;; Local files are handled slightly oddly
 195             (if (featurep 'ange-ftp)
 196                 (url-file-asynch-callback nil nil
 197                                           filename
 198                                           (current-buffer)
 199                                           callback cbargs)
 200               (url-file-asynch-callback nil nil nil
 201                                         filename
 202                                         (current-buffer)
 203                                         callback cbargs))
 204           ;; FTP handling
 205           (let* ((extension (url-file-extension filename))
 206                  (new (url-generate-unique-filename
 207                        (and (> (length extension) 0)
 208                             (concat "%s." extension)))))
 209             (if (featurep 'ange-ftp)
 210                 (ange-ftp-copy-file-internal filename (expand-file-name new) t
 211                                              nil t
 212                                              (list 'url-file-asynch-callback
 213                                                    new (current-buffer)
 214                                                    callback cbargs)
 215                                              t)
 216               (when (featurep 'xemacs)
 217                 (autoload 'efs-copy-file-internal "efs")
 218                 (efs-copy-file-internal filename (efs-ftp-path filename)
 219                                         new (efs-ftp-path new)
 220                                         t nil 0
 221                                         (list 'url-file-asynch-callback
 222                                               new (current-buffer)
 223                                               callback cbargs)
 224                                         0 nil)))))))
 225     buffer))
 226
 227 (defmacro url-file-create-wrapper (method args)
 228   `(defalias ',(intern (format "url-ftp-%s" method))
 229      (defun ,(intern (format "url-file-%s" method)) ,args
 230        ,(format "FTP/FILE URL wrapper around `%s' call." method)
 231        (setq url (url-file-build-filename url))
 232        (and url (,method ,@(remove '&rest (remove '&optional args)))))))
 233
 234 (url-file-create-wrapper file-exists-p (url))
 235 (url-file-create-wrapper file-attributes (url &optional id-format))
 236 (url-file-create-wrapper file-symlink-p (url))
 237 (url-file-create-wrapper file-readable-p (url))
 238 (url-file-create-wrapper file-writable-p (url))
 239 (url-file-create-wrapper file-executable-p (url))
 240 (url-file-create-wrapper directory-files (url &optional full match nosort))
 241 (url-file-create-wrapper file-truename (url &optional counter prev-dirs))
 242
 243 (provide 'url-file)
 244
 245 ;; arch-tag: 010e914a-7313-494b-8a8c-6495a862157d
 246 ;;; url-file.el ends here