1;;; url-methods.el --- Load URL schemes as needed 2 3;; Copyright (C) 1996, 1997, 1998, 1999, 2004, 4;; 2005, 2006, 2007 Free Software Foundation, Inc. 5 6;; Keywords: comm, data, processes, hypermedia 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 2, or (at your option) 13;; 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; see the file COPYING. If not, write to the 22;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, 23;; Boston, MA 02110-1301, USA. 24 25;;; Commentary: 26 27;;; Code: 28 29(eval-when-compile 30 (require 'cl)) 31 32;; This loads up some of the small, silly URLs that I really don't 33;; want to bother putting in their own separate files. 34(require 'url-parse) 35 36(defvar url-scheme-registry (make-hash-table :size 7 :test 'equal)) 37 38(defconst url-scheme-methods 39 '((default-port . variable) 40 (asynchronous-p . variable) 41 (expand-file-name . function) 42 (file-exists-p . function) 43 (file-attributes . function) 44 (parse-url . function) 45 (file-symlink-p . function) 46 (file-writable-p . function) 47 (file-directory-p . function) 48 (file-executable-p . function) 49 (directory-files . function) 50 (file-truename . function)) 51 "Assoc-list of methods that each URL loader can provide.") 52 53(defconst url-scheme-default-properties 54 (list 'name "unknown" 55 'loader 'url-scheme-default-loader 56 'default-port 0 57 'expand-file-name 'url-identity-expander 58 'parse-url 'url-generic-parse-url 59 'asynchronous-p nil 60 'file-directory-p 'ignore 61 'file-truename (lambda (&rest args) 62 (url-recreate-url (car args))) 63 'file-exists-p 'ignore 64 'file-attributes 'ignore)) 65 66(defun url-scheme-default-loader (url &optional callback cbargs) 67 "Signal an error for an unknown URL scheme." 68 (error "Unkown URL scheme: %s" (url-type url))) 69 70(defun url-scheme-register-proxy (scheme) 71 "Automatically find a proxy for SCHEME and put it in `url-proxy-services'." 72 (let* ((env-var (concat scheme "_proxy")) 73 (env-proxy (or (getenv (upcase env-var)) 74 (getenv (downcase env-var)))) 75 (cur-proxy (assoc scheme url-proxy-services)) 76 (urlobj nil)) 77 78 ;; If env-proxy is an empty string, treat it as if it were nil 79 (when (and (stringp env-proxy) 80 (string= env-proxy "")) 81 (setq env-proxy nil)) 82 83 ;; Store any proxying information - this will not overwrite an old 84 ;; entry, so that people can still set this information in their 85 ;; .emacs file 86 (cond 87 (cur-proxy nil) ; Keep their old settings 88 ((null env-proxy) nil) ; No proxy setup 89 ;; First check if its something like hostname:port 90 ((string-match "^\\([^:]+\\):\\([0-9]+\\)$" env-proxy) 91 (setq urlobj (url-generic-parse-url nil)) ; Get a blank object 92 (url-set-type urlobj "http") 93 (url-set-host urlobj (match-string 1 env-proxy)) 94 (url-set-port urlobj (string-to-number (match-string 2 env-proxy)))) 95 ;; Then check if its a fully specified URL 96 ((string-match url-nonrelative-link env-proxy) 97 (setq urlobj (url-generic-parse-url env-proxy)) 98 (url-set-type urlobj "http") 99 (url-set-target urlobj nil)) 100 ;; Finally, fall back on the assumption that its just a hostname 101 (t 102 (setq urlobj (url-generic-parse-url nil)) ; Get a blank object 103 (url-set-type urlobj "http") 104 (url-set-host urlobj env-proxy))) 105 106 (if (and (not cur-proxy) urlobj) 107 (progn 108 (setq url-proxy-services 109 (cons (cons scheme (format "%s:%d" (url-host urlobj) 110 (url-port urlobj))) 111 url-proxy-services)) 112 (message "Using a proxy for %s..." scheme))))) 113 114(defun url-scheme-get-property (scheme property) 115 "Get property of a URL SCHEME. 116Will automatically try to load a backend from url-SCHEME.el if 117it has not already been loaded." 118 (setq scheme (downcase scheme)) 119 (let ((desc (gethash scheme url-scheme-registry))) 120 (if (not desc) 121 (let* ((stub (concat "url-" scheme)) 122 (loader (intern stub))) 123 (condition-case () 124 (require loader) 125 (error nil)) 126 (if (fboundp loader) 127 (progn 128 ;; Found the module to handle <scheme> URLs 129 (url-scheme-register-proxy scheme) 130 (setq desc (list 'name scheme 131 'loader loader)) 132 (dolist (cell url-scheme-methods) 133 (let ((symbol (intern-soft (format "%s-%s" stub (car cell)))) 134 (type (cdr cell))) 135 (if symbol 136 (case type 137 (function 138 ;; Store the symbol name of a function 139 (if (fboundp symbol) 140 (setq desc (plist-put desc (car cell) symbol)))) 141 (variable 142 ;; Store the VALUE of a variable 143 (if (boundp symbol) 144 (setq desc (plist-put desc (car cell) 145 (symbol-value symbol))))) 146 (otherwise 147 (error "Malformed url-scheme-methods entry: %S" 148 cell)))))) 149 (puthash scheme desc url-scheme-registry))))) 150 (or (plist-get desc property) 151 (plist-get url-scheme-default-properties property)))) 152 153(provide 'url-methods) 154 155;; arch-tag: 336863f8-5a07-4906-9be5-b3c6bcebbe67 156;;; url-methods.el ends here 157