;; Author: Tim Vaughan <tgvaughan@gmail.com>
;; Created: 11 April 2019
-;; Version: 1.4.1
+;; Version: 1.4.3
;; Keywords: comm gopher
;; Homepage: https://github.com/tgvaughan/elpher
;; Package-Requires: ((emacs "25"))
;;; Commentary:
-;; Elpher aims to provide a practical gopher client for GNU Emacs.
-;; It supports:
+;; Elpher aims to provide a practical and friendly gopher client
+;; for GNU Emacs. It supports:
-;; - intuitive keyboard and mouse-driven interface,
+;; - an intuitive keyboard and mouse-driven interface,
+;; - followable web and gopher links in plain text,
;; - caching of visited sites (both content and cursor position),
;; - pleasant and configurable colouring of Gopher directories,
;; - direct visualisation of image files,
;; - (m)enu key support, similar to Emacs' info browser,
-;; - clickable web and gopher links in plain text,
;; - a simple bookmark management system,
-;; - support for TLS gopherholes.
+;; - support for TLS.
;; To launch Elpher, simply use 'M-x elpher'. This will open a start
;; page containing information on key bindings and suggested starting
;; points for your gopher exploration.
-;; Faces, caching and other options can be configured via
-;; the Elpher customization group in Applications.
+;; Further instructions can be found in the Elpher info manual.
+
+;; Elpher is under active development, and any suggestions for
+;; improvements are welcome!
;;; Code:
;;; Global constants
;;
-(defconst elpher-version "1.4.1"
+(defconst elpher-version "1.4.3"
"Current version of elpher.")
(defconst elpher-margin-width 6
"i - r: redraw current page (using cached contents if available)\tfake\tfake\t1"
"i - R: reload current page (regenerates cache)\tfake\tfake\t1"
"i - T: toggle TLS mode\tfake\tfake\t1"
- "i - d: download directory entry under cursor\tfake\tfake\t1"
+ "i - d/D: download item under cursor or current page\tfake\tfake\t1"
"i - w: display the raw server response for the current page\tfake\tfake\t1"
"i - S: set an explicit character coding system (default is to autodetect)\tfake\tfake\t1"
"i\tfake\tfake\t1"
"If non-nil, display current node information in buffer header."
:type '(boolean))
+(defcustom elpher-auto-disengage-TLS nil
+ "If non-nil, automatically disengage TLS following an unsuccessful connection.
+While enabling this may seem convenient, it is also potentially dangerous as it
+allows switching from an encrypted channel back to plain text without user input."
+ :type '(boolean))
+
+
;;; Model
;;
(elt address 3))
(defun elpher-address-use-tls-p (address)
- "Returns non-nil if ADDRESS is marked as needing TLS."
+ "Return non-nil if ADDRESS is marked as needing TLS."
(elt address 4))
(defun elpher-address-special-p (address)
(defun elpher-insert-index-record (display-string address)
"Function to insert an index record into the current buffer.
The contents of the record are dictated by DISPLAY-STRING and ADDRESS."
- (let ((type-map-entry (alist-get (elpher-address-type address)
- elpher-type-map)))
+ (let* ((type (elpher-address-type address))
+ (type-map-entry (alist-get type elpher-type-map)))
(if type-map-entry
(let* ((margin-code (elt type-map-entry 1))
(face (elt type-map-entry 2))
(defvar elpher-selector-string)
-(defun elpher-get-selector (address after)
+(defun elpher-get-selector (address after &optional propagate-error)
"Retrieve selector specified by ADDRESS, then execute AFTER.
-The result is stored as a string in the variable ‘elpher-selector-string’."
+The result is stored as a string in the variable ‘elpher-selector-string’.
+
+Usually errors result in an error page being displayed. This is only
+appropriate if the selector is to be directly viewed. If PROPAGATE-ERROR
+is non-nil, this message is not displayed. Instead, the error propagates
+up to the calling function."
(setq elpher-selector-string "")
- (when (and (elpher-address-use-tls-p address)
- (not elpher-use-tls)
- (gnutls-available-p))
- (setq elpher-use-tls t)
- (message "Engaging TLS mode."))
+ (when (elpher-address-use-tls-p address)
+ (if (gnutls-available-p)
+ (when (not elpher-use-tls)
+ (setq elpher-use-tls t)
+ (message "Engaging TLS mode."))
+ (error "Cannot retrieve TLS selector: GnuTLS not available")))
(condition-case the-error
(let* ((kill-buffer-query-functions nil)
(proc (open-network-stream "elpher-process"
(elpher-address-host address)
(elpher-address-port address)
:type (if elpher-use-tls 'tls 'plain))))
+ (set-process-coding-system proc 'binary)
(set-process-filter proc
(lambda (proc string)
(setq elpher-selector-string
(error
(if (and (consp the-error)
(eq (car the-error) 'gnutls-error)
- (not (elpher-address-use-tls-p address)))
+ (not (elpher-address-use-tls-p address))
+ (or elpher-auto-disengage-TLS
+ (yes-or-no-p "Could not establish encrypted connection. Disable TLS mode? ")))
(progn
- (message "Could not establish TLS connection. Disengaging TLS mode.")
+ (message "Disengaging TLS mode.")
(setq elpher-use-tls nil)
(elpher-get-selector address after))
(elpher-process-cleanup)
- (elpher-with-clean-buffer
- (insert (propertize "\n---- ERROR -----\n\n" 'face 'error)
- "Failed to connect to " (elpher-get-address-url address) ".\n"
- (propertize "\n----------------\n\n" 'face 'error)
- "Press 'u' to return to the previous page."))))))
+ (if propagate-error
+ (error the-error)
+ (elpher-with-clean-buffer
+ (insert (propertize "\n---- ERROR -----\n\n" 'face 'error)
+ "Failed to connect to " (elpher-get-address-url address) ".\n"
+ (propertize "\n----------------\n\n" 'face 'error)
+ "Press 'u' to return to the previous page.")))))))
;; Index retrieval
"gopher.file"))))
(message "Downloading...")
(setq elpher-download-filename filename)
- (elpher-get-selector address
- (lambda (proc event)
- (let ((coding-system-for-write 'binary))
- (with-temp-file elpher-download-filename
- (insert elpher-selector-string)
- (message (format "Download complate, saved to file %s."
- elpher-download-filename)))))))))
+ (condition-case the-error
+ (elpher-get-selector address
+ (lambda (proc event)
+ (let ((coding-system-for-write 'binary))
+ (with-temp-file elpher-download-filename
+ (insert elpher-selector-string)
+ (message (format "Download complate, saved to file %s."
+ elpher-download-filename)))))
+ t)
+ (error
+ (error "Error downloading %s" elpher-download-filename))))))
;; URL retrieval
(message "No current site.")))
(defun elpher-toggle-tls ()
- "Toggle TLS mode."
+ "Toggle TLS encryption mode."
(interactive)
(setq elpher-use-tls (not elpher-use-tls))
(if elpher-use-tls
- (message "TLS mode enabled. (Will not affect current page until reload.)")
+ (if (gnutls-available-p)
+ (message "TLS mode enabled. (Will not affect current page until reload.)")
+ (setq elpher-use-tls nil)
+ (error "Cannot enable TLS mode: GnuTLS not available"))
(message "TLS mode disabled. (Will not affect current page until reload.)")))
(defun elpher-view-raw ()
#'elpher-get-node-download)))
(error "No link selected"))))
+(defun elpher-download-current ()
+ "Download the current page."
+ (interactive)
+ (if (elpher-address-special-p (elpher-node-address elpher-current-node))
+ (error "Cannot download this page")
+ (elpher-visit-node (elpher-make-node
+ (elpher-node-display-string elpher-current-node)
+ (elpher-node-address elpher-current-node)
+ elpher-current-node)
+ #'elpher-get-node-download
+ t)))
+
(defun elpher-build-link-map ()
"Build alist mapping link names to destination nodes in current buffer."
(let ((link-map nil)
(error "No link selected"))))
(defun elpher-bookmarks ()
- "Visit bookmarks."
+ "Visit bookmarks page."
(interactive)
(switch-to-buffer "*elpher*")
(elpher-visit-node
(define-key map (kbd "T") 'elpher-toggle-tls)
(define-key map (kbd "w") 'elpher-view-raw)
(define-key map (kbd "d") 'elpher-download)
+ (define-key map (kbd "D") 'elpher-download-current)
(define-key map (kbd "m") 'elpher-jump)
(define-key map (kbd "i") 'elpher-info-link)
(define-key map (kbd "I") 'elpher-info-current)
(kbd "T") 'elpher-toggle-tls
(kbd "w") 'elpher-view-raw
(kbd "d") 'elpher-download
+ (kbd "D") 'elpher-download-current
(kbd "m") 'elpher-jump
(kbd "i") 'elpher-info-link
(kbd "I") 'elpher-info-current
"Keymap for gopher client.")
(define-derived-mode elpher-mode special-mode "elpher"
- "Major mode for elpher, an elisp gopher client.")
+ "Major mode for elpher, an elisp gopher client.
+
+This mode is automatically enabled by the interactive
+functions which initialize the gopher client, namely
+`elpher', `elpher-go' and `elpher-bookmarks'.")
(when (fboundp 'evil-set-initial-state)
(evil-set-initial-state 'elpher-mode 'motion))
The Lambda Lab / projects / elpher.git / blobdiff