-;;; elpher.el --- Full-featured gopher client.
+;;; elpher.el --- A friendly gopher client.
;; Copyright (C) 2019 Tim Vaughan
;; Author: Tim Vaughan <tgvaughan@gmail.com>
;; Created: 11 April 2019
-;; Version: 1.1.0
+;; Version: 1.4.3
;; Keywords: comm gopher
;; Homepage: https://github.com/tgvaughan/elpher
;; Package-Requires: ((emacs "25"))
;;; Commentary:
-;; Elpher aims to provide a full-featured 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 browsing,
+;; - 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.
-
-;; Visited pages are stored as a hierarchy rather than a linear history,
-;; meaning that navigation between these pages is quick and easy.
+;; - a simple bookmark management system,
+;; - 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 options and start page 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:
(provide 'elpher)
(require 'seq)
(require 'pp)
+(require 'shr)
;;; Global constants
;;
-(defconst elpher-version "1.1.0"
+(defconst elpher-version "1.4.3"
"Current version of elpher.")
(defconst elpher-margin-width 6
"i - m: select an item on current page by name (autocompletes)\tfake\tfake\t1"
"i - u: return to parent\tfake\tfake\t1"
"i - O: visit the root menu of the current server\tfake\tfake\t1"
- "i - g: go to a particular menu or item\tfake\tfake\t1"
+ "i - g: go to a particular gopher address\tfake\tfake\t1"
"i - i/I: info on item under cursor or current page\tfake\tfake\t1"
"i - c/C: copy URL representation of item under cursor or current page\tfake\tfake\t1"
+ "i - a/A: bookmark the item under cursor or current page\tfake\tfake\t1"
+ "i - x/X: remove bookmark for item under cursor or current page\tfake\tfake\t1"
+ "i - B: visit the bookmarks page\tfake\tfake\t1"
"i - r: redraw current page (using cached contents if available)\tfake\tfake\t1"
"i - R: reload current page (regenerates cache)\tfake\tfake\t1"
- "i - d: download directory entry under cursor\tfake\tfake\t1"
+ "i - T: toggle TLS mode\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"
- "iPlaces to start exploring Gopherspace:\tfake\tfake\t1"
+ "iWhere to start exploring Gopherspace:\tfake\tfake\t1"
"i\tfake\tfake\t1"
- "1Floodgap Systems Gopher Server\t\tgopher.floodgap.com\t70"
+ "1Floodgap Systems Gopher Server\t/\tgopher.floodgap.com\t70"
"i\tfake\tfake\t1"
"iAlternatively, select the following item and enter some\tfake\tfake\t1"
"isearch terms:\tfake\tfake\t1"
"Source for elpher start page.")
(defconst elpher-type-map
- '((?0 elpher-get-text-node "T" elpher-text)
+ '((?0 elpher-get-text-node "txt" elpher-text)
(?1 elpher-get-index-node "/" elpher-index)
- (?4 elpher-get-node-download "B" elpher-binary)
- (?5 elpher-get-node-download "B" elpher-binary)
+ (?4 elpher-get-node-download "bin" elpher-binary)
+ (?5 elpher-get-node-download "bin" elpher-binary)
(?7 elpher-get-search-node "?" elpher-search)
- (?8 elpher-get-telnet-node "?" elpher-telnet)
- (?9 elpher-get-node-download "B" elpher-binary)
- (?g elpher-get-image-node "im" elpher-image)
- (?p elpher-get-image-node "im" elpher-image)
- (?I elpher-get-image-node "im" elpher-image)
- (?h elpher-get-url-node "W" elpher-url))
+ (?8 elpher-get-telnet-node "tel" elpher-telnet)
+ (?9 elpher-get-node-download "bin" elpher-binary)
+ (?g elpher-get-image-node "img" elpher-image)
+ (?p elpher-get-image-node "img" elpher-image)
+ (?I elpher-get-image-node "img" elpher-image)
+ (?d elpher-get-node-download "doc" elpher-binary)
+ (?h elpher-get-url-node "web" elpher-url)
+ (bookmarks elpher-get-bookmarks-node "#" elpher-index)
+ (start elpher-get-start-node "#" elpher-index))
"Association list from types to getters, margin codes and index faces.")
;; Face customizations
(defface elpher-index
- '((t :inherit org-drawer))
+ '((t :inherit font-lock-keyword-face))
"Face used for directory type directory records.")
(defface elpher-text
- '((t :inherit org-tag))
+ '((t :inherit bold))
"Face used for text type directory records.")
(defface elpher-info
- '((t :inherit org-default))
+ '((t :inherit default))
"Face used for info type directory records.")
(defface elpher-image
- '((t :inherit org-level-4))
+ '((t :inherit font-lock-string-face))
"Face used for image type directory records.")
(defface elpher-search
- '((t :inherit org-level-5))
+ '((t :inherit warning))
"Face used for search type directory records.")
(defface elpher-url
- '((t :inherit org-level-6))
+ '((t :inherit font-lock-comment-face))
"Face used for url type directory records.")
(defface elpher-telnet
- '((t :inherit org-level-6))
+ '((t :inherit font-lock-function-name-face))
"Face used for telnet type directory records.")
(defface elpher-binary
- '((t :inherit org-level-7))
+ '((t :inherit font-lock-doc-face))
"Face used for binary type directory records.")
(defface elpher-unknown
- '((t :inherit org-warning))
+ '((t :inherit error))
"Face used for directory records with unknown/unsupported types.")
(defface elpher-margin-key
- '((t :inherit org-tag))
+ '((t :inherit bold))
"Face used for directory margin key.")
(defface elpher-margin-brackets
- '((t :inherit org-special-keyword))
+ '((t :inherit shadow))
"Face used for brackets around directory margin key.")
;; Other customizations
"If non-nil, cache images in memory in the same way as other content."
:type '(boolean))
-(defcustom elpher-start-address nil
- "If nil, the default start directory is shown when Elpher is started.
-Otherwise, a list containing the selector, host and port of a directory to
-use as the start page."
- :type '(list string string integer))
-
(defcustom elpher-use-header t
"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
;;
;; Address
-(defun elpher-make-address (type selector host port)
- "Create an address of a gopher object with TYPE, SELECTOR, HOST and PORT."
- (list type selector host port))
+(defun elpher-make-address (type &optional selector host port use-tls)
+ "Create an address of a gopher object with TYPE, SELECTOR, HOST and PORT.
+Although selector host and port are optional, they are only omitted for
+special address types, such as 'start for the start page.
+
+Setting the USE-TLS parameter to non-nil causes Elpher to engage TLS mode
+before attempting to connect to the server."
+ (if use-tls
+ (list type selector host port 'tls)
+ (list type selector host port)))
(defun elpher-address-type (address)
"Retrieve type from ADDRESS."
"Retrieve port from ADDRESS."
(elt address 3))
+(defun elpher-address-use-tls-p (address)
+ "Return non-nil if ADDRESS is marked as needing TLS."
+ (elt address 4))
+
+(defun elpher-address-special-p (address)
+ "Return non-nil if ADDRESS is special (e.g. start page, bookmarks page)."
+ (not (elpher-address-host address)))
+
;; Node
-(defun elpher-make-node (display-string parent address &optional content pos)
+(defun elpher-make-node (display-string address &optional parent)
"Create a node in the gopher page hierarchy.
DISPLAY-STRING records the display string used for the page.
-PARENT specifies the parent of the node, and ADDRESS specifies the
-address of the gopher page.
+ADDRESS specifies the address of the gopher page.
-The optional arguments CONTENT and POS can be used to fill the cached
-content and cursor position fields of the node."
- (list display-string parent address content pos))
+The optional PARENT specifies the parent node in the hierarchy.
+This is set every time the node is visited, so while it forms
+an important part of the node data there is no need to set it
+initially."
+ (list display-string address parent))
(defun elpher-node-display-string (node)
"Retrieve the display string of NODE."
(elt node 0))
-(defun elpher-node-parent (node)
- "Retrieve the parent node of NODE."
- (elt node 1))
-
(defun elpher-node-address (node)
"Retrieve the address of NODE."
+ (elt node 1))
+
+(defun elpher-node-parent (node)
+ "Retrieve the parent node of NODE."
(elt node 2))
-(defun elpher-node-content (node)
- "Retrieve the cached content of NODE, or nil if none exists."
- (elt node 3))
+(defun elpher-set-node-parent (node parent)
+ "Set the parent node of NODE to be PARENT."
+ (setcar (cdr (cdr node)) parent))
+
+;; Cache
-(defun elpher-node-pos (node)
- "Retrieve the cached cursor position for NODE, or nil if none exists."
- (elt node 4))
+(defvar elpher-content-cache (make-hash-table :test 'equal))
+(defvar elpher-pos-cache (make-hash-table :test 'equal))
-(defun elpher-set-node-content (node content)
- "Set the content cache of NODE to CONTENT."
- (setcar (nthcdr 3 node) content))
+(defun elpher-get-cached-content (address)
+ "Retrieve the cached content for ADDRESS, or nil if none exists."
+ (gethash address elpher-content-cache))
-(defun elpher-set-node-pos (node pos)
- "Set the cursor position cache of NODE to POS."
- (setcar (nthcdr 4 node) pos))
+(defun elpher-cache-content (address content)
+ "Set the content cache for ADDRESS to CONTENT."
+ (puthash address content elpher-content-cache))
+
+(defun elpher-get-cached-pos (address)
+ "Retrieve the cached cursor position for ADDRESS, or nil if none exists."
+ (gethash address elpher-pos-cache))
+
+(defun elpher-cache-pos (address pos)
+ "Set the cursor position cache for ADDRESS to POS."
+ (puthash address pos elpher-pos-cache))
;; Node graph traversal
(defvar elpher-current-node nil)
-(defun elpher-visit-node (node &optional getter)
- "Visit NODE using its own getter or GETTER, if non-nil."
+(defun elpher-visit-node (node &optional getter preserve-parent)
+ "Visit NODE using its own getter or GETTER, if non-nil.
+Additionally, set the parent of NODE to `elpher-current-node',
+unless PRESERVE-PARENT is non-nil."
(elpher-save-pos)
(elpher-process-cleanup)
+ (unless preserve-parent
+ (if (and (elpher-node-parent elpher-current-node)
+ (equal (elpher-node-address elpher-current-node)
+ (elpher-node-address node)))
+ (elpher-set-node-parent node (elpher-node-parent elpher-current-node))
+ (elpher-set-node-parent node elpher-current-node)))
(setq elpher-current-node node)
- (with-current-buffer "*elpher*"
- (setq header-line-format "hello"))
- ;; (let ((inhibit-read-only t))
-
- ;; (force-mode-line-update))
(if getter
(funcall getter)
(let* ((address (elpher-node-address node))
- (type (if address
- (elpher-address-type address)
- ?1)))
+ (type (elpher-address-type address)))
(funcall (car (alist-get type elpher-type-map))))))
(defun elpher-visit-parent-node ()
"Visit the parent of the current node."
(let ((parent-node (elpher-node-parent elpher-current-node)))
(when parent-node
- (elpher-visit-node parent-node))))
+ (elpher-visit-node parent-node nil t))))
(defun elpher-reload-current-node ()
"Reload the current node, discarding any existing cached content."
- (elpher-set-node-content elpher-current-node nil)
+ (elpher-cache-content (elpher-node-address elpher-current-node) nil)
(elpher-visit-node elpher-current-node))
(defun elpher-save-pos ()
"Save the current position of point to the current node."
(when elpher-current-node
- (elpher-set-node-pos elpher-current-node (point))))
+ (elpher-cache-pos (elpher-node-address elpher-current-node) (point))))
(defun elpher-restore-pos ()
"Restore the position of point to that cached in the current node."
- (let ((pos (elpher-node-pos elpher-current-node)))
+ (let ((pos (elpher-get-cached-pos (elpher-node-address elpher-current-node))))
(if pos
(goto-char pos)
(goto-char (point-min)))))
args)))
+;;; Text Processing
+;;
+
+(defvar elpher-user-coding-system nil
+ "User-specified coding system to use for decoding text responses.")
+
+(defun elpher-decode (string)
+ "Decode STRING using autodetected or user-specified coding system."
+ (decode-coding-string string
+ (if elpher-user-coding-system
+ elpher-user-coding-system
+ (detect-coding-string string t))))
+
+(defun elpher-preprocess-text-response (string)
+ "Preprocess text selector response contained in STRING.
+This involes decoding the character representation, and clearing
+away CRs and any terminating period."
+ (elpher-decode (replace-regexp-in-string "\n\.\n$" "\n"
+ (replace-regexp-in-string "\r" "" string))))
+
;;; Index rendering
;;
"Insert the index corresponding to STRING into the current buffer."
;; Should be able to split directly on CRLF, but some non-conformant
;; LF-only servers sadly exist, hence the following.
- (let* ((str-no-period (replace-regexp-in-string "\r\n\.\r\n$" "\r\n" string))
- (str-no-cr (replace-regexp-in-string "\r" "" str-no-period)))
- (dolist (line (split-string str-no-cr "\n"))
+ (let ((str-processed (elpher-preprocess-text-response string)))
+ (dolist (line (split-string str-processed "\n"))
(unless (= (length line) 0)
- (elpher-insert-index-record line)))))
+ (let* ((type (elt line 0))
+ (fields (split-string (substring line 1) "\t"))
+ (display-string (elt fields 0))
+ (selector (elt fields 1))
+ (host (elt fields 2))
+ (port (if (elt fields 3)
+ (string-to-number (elt fields 3))
+ nil))
+ (address (elpher-make-address type selector host port)))
+ (elpher-insert-index-record display-string address))))))
(defun elpher-insert-margin (&optional type-name)
"Insert index margin, optionally containing the TYPE-NAME, into the current buffer."
(elpher-address-host address)
(elpher-address-port address)))))
-(defun elpher-insert-index-record (line)
- "Insert the index record corresponding to LINE into the current buffer."
- (let* ((type (elt line 0))
- (fields (split-string (substring line 1) "\t"))
- (display-string (elt fields 0))
- (selector (elt fields 1))
- (host (elt fields 2))
- (port (string-to-number (elt fields 3))))
- (elpher-insert-index-record-helper display-string type selector host port)))
-
-(defun elpher-insert-index-record-helper (display-string type selector host port)
- "Helper function to insert an index record into the current buffer.
-The contents of the record are dictated by TYPE, DISPLAY-STRING, SELECTOR, HOST
-and PORT.
-
-This function is essentially the second half of `elpher-insert-index-record',
-but broken out so that it can be used elsewhere."
- (let ((address (elpher-make-address type selector host port))
- (type-map-entry (alist-get type elpher-type-map)))
+
+(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 (elpher-address-type address))
+ (type-map-entry (alist-get type elpher-type-map)))
(if type-map-entry
- (let* ((margin-code (cadr type-map-entry))
- (face (caddr type-map-entry))
- (node (elpher-make-node display-string elpher-current-node address)))
+ (let* ((margin-code (elt type-map-entry 1))
+ (face (elt type-map-entry 2))
+ (node (elpher-make-node display-string address)))
(elpher-insert-margin margin-code)
(insert-text-button display-string
'face face
(other ;; Unknown
(elpher-insert-margin (concat (char-to-string type) "?"))
(insert (propertize display-string
- 'face 'elpher-unknown-face)))))
+ 'face 'elpher-unknown)))))
(insert "\n")))
(defun elpher-click-link (button)
(let ((p (get-process "elpher-process")))
(if p (delete-process p))))
+(defvar elpher-use-tls nil
+ "If non-nil, use TLS to communicate with gopher servers.")
+
(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 "")
- (make-network-process
- :name "elpher-process"
- :host (elpher-address-host address)
- :service (elpher-address-port address)
- :filter (lambda (proc string)
- (setq elpher-selector-string (concat elpher-selector-string string)))
- :sentinel after)
- (process-send-string "elpher-process"
- (concat (elpher-address-selector address) "\n")))
+ (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"
+ nil
+ (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
+ (concat elpher-selector-string string))))
+ (set-process-sentinel proc after)
+ (process-send-string proc
+ (concat (elpher-address-selector address) "\n")))
+ (error
+ (if (and (consp the-error)
+ (eq (car the-error) 'gnutls-error)
+ (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 "Disengaging TLS mode.")
+ (setq elpher-use-tls nil)
+ (elpher-get-selector address after))
+ (elpher-process-cleanup)
+ (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
(defun elpher-get-index-node ()
"Getter which retrieves the current node contents as an index."
- (let ((content (elpher-node-content elpher-current-node))
- (address (elpher-node-address elpher-current-node)))
+ (let* ((address (elpher-node-address elpher-current-node))
+ (content (elpher-get-cached-content address)))
(if content
(progn
(elpher-with-clean-buffer
(insert content)
(elpher-restore-pos)))
- (if address
- (progn
- (elpher-with-clean-buffer
- (insert "LOADING DIRECTORY..."))
- (elpher-get-selector address
- (lambda (proc event)
- (unless (string-prefix-p "deleted" event)
- (elpher-with-clean-buffer
- (elpher-insert-index elpher-selector-string)
- (elpher-restore-pos)
- (elpher-set-node-content elpher-current-node
- (buffer-string)))))))
- (progn
- (elpher-with-clean-buffer
- (elpher-insert-index elpher-start-index)
- (elpher-restore-pos)
- (elpher-set-node-content elpher-current-node
- (buffer-string))))))))
+ (elpher-with-clean-buffer
+ (insert "LOADING DIRECTORY... (use 'u' to cancel)"))
+ (elpher-get-selector address
+ (lambda (proc event)
+ (unless (string-prefix-p "deleted" event)
+ (elpher-with-clean-buffer
+ (elpher-insert-index elpher-selector-string)
+ (elpher-restore-pos)
+ (elpher-cache-content
+ (elpher-node-address elpher-current-node)
+ (buffer-string)))))))))
;; Text retrieval
"\\([a-zA-Z]+\\)://\\([a-zA-Z0-9.\-]+\\)\\(?3::[0-9]+\\)?\\(?4:/[^ \r\n\t(),]*\\)?"
"Regexp used to locate and buttinofy URLs in text files loaded by elpher.")
-(defun elpher-make-node-from-matched-url (parent &optional string)
+(defun elpher-make-node-from-matched-url (&optional string)
"Convert most recent `elpher-url-regex' match to a node.
-PARENT defines the node to set as the parent to the new node.
-
If STRING is non-nil, this is given as an argument to all `match-string'
calls, as is necessary if the match is performed by `string-match'."
(let ((url (match-string 0 string))
(protocol (downcase (match-string 1 string))))
- (if (string= protocol "gopher")
+ (if (or (string= protocol "gopher")
+ (string= protocol "gophers"))
(let* ((host (match-string 2 string))
(port (if (> (length (match-string 3 string)) 1)
(string-to-number (substring (match-string 3 string) 1))
(selector (if (> (length type-and-selector) 1)
(substring type-and-selector 2)
""))
- (address (elpher-make-address type selector host port)))
- (elpher-make-node url elpher-current-node address))
+ (use-tls (string= protocol "gophers"))
+ (address (elpher-make-address type selector host port use-tls)))
+ (elpher-make-node url address))
(let* ((host (match-string 2 string))
(port (if (> (length (match-string 3 string)) 1)
(string-to-number (substring (match-string 3 string) 1))
70))
(selector (concat "URL:" url))
(address (elpher-make-address ?h selector host port)))
- (elpher-make-node url elpher-current-node address)))))
+ (elpher-make-node url address)))))
(defun elpher-buttonify-urls (string)
(insert string)
(goto-char (point-min))
(while (re-search-forward elpher-url-regex nil t)
- (let ((node (elpher-make-node-from-matched-url elpher-current-node)))
+ (let ((node (elpher-make-node-from-matched-url)))
(make-text-button (match-beginning 0)
(match-end 0)
'elpher-node node
'help-echo (elpher-node-button-help node))))
(buffer-string)))
-(defun elpher-process-text (string)
- "Remove CRs and trailing period from the gopher text document STRING."
- (let* ((chopped-str (replace-regexp-in-string "\r\n\.\r\n$" "\r\n" string))
- (cleaned-str (replace-regexp-in-string "\r" "" chopped-str)))
- (elpher-buttonify-urls cleaned-str)))
-
(defun elpher-get-text-node ()
"Getter which retrieves the current node contents as a text document."
- (let ((content (elpher-node-content elpher-current-node))
- (address (elpher-node-address elpher-current-node)))
+ (let* ((address (elpher-node-address elpher-current-node))
+ (content (elpher-get-cached-content address)))
(if content
(progn
(elpher-with-clean-buffer
(elpher-restore-pos)))
(progn
(elpher-with-clean-buffer
- (insert "LOADING TEXT..."))
+ (insert "LOADING TEXT... (use 'u' to cancel)"))
(elpher-get-selector address
(lambda (proc event)
(unless (string-prefix-p "deleted" event)
(elpher-with-clean-buffer
- (insert (elpher-process-text elpher-selector-string))
+ (insert (elpher-buttonify-urls
+ (elpher-preprocess-text-response
+ elpher-selector-string)))
(elpher-restore-pos)
- (elpher-set-node-content elpher-current-node
- (buffer-string))))))))))
+ (elpher-cache-content
+ (elpher-node-address elpher-current-node)
+ (buffer-string))))))))))
;; Image retrieval
(defun elpher-get-image-node ()
"Getter which retrieves the current node contents as an image to view."
- (let ((content (elpher-node-content elpher-current-node))
- (address (elpher-node-address elpher-current-node)))
+ (let* ((address (elpher-node-address elpher-current-node))
+ (content (elpher-get-cached-content address)))
(if content
(progn
(elpher-with-clean-buffer
(if (display-images-p)
(progn
(elpher-with-clean-buffer
- (insert "LOADING IMAGE..."))
+ (insert "LOADING IMAGE... (use 'u' to cancel)"))
(elpher-get-selector address
(lambda (proc event)
(unless (string-prefix-p "deleted" event)
(let ((image (create-image
- (encode-coding-string elpher-selector-string
- 'no-conversion)
+ elpher-selector-string
nil t)))
(elpher-with-clean-buffer
(insert-image image)
(elpher-restore-pos))
(if elpher-cache-images
- (elpher-set-node-content elpher-current-node
- image)))))))
+ (elpher-cache-content
+ (elpher-node-address elpher-current-node)
+ image)))))))
(elpher-get-node-download)))))
;; Search retrieval
(defun elpher-get-search-node ()
"Getter which submits a search query to the address of the current node."
- (let ((content (elpher-node-content elpher-current-node))
- (address (elpher-node-address elpher-current-node))
- (aborted t))
+ (let* ((address (elpher-node-address elpher-current-node))
+ (content (elpher-get-cached-content address))
+ (aborted t))
(if content
(progn
(elpher-with-clean-buffer
(elpher-address-port address))))
(setq aborted nil)
(elpher-with-clean-buffer
- (insert "LOADING RESULTS..."))
+ (insert "LOADING RESULTS... (use 'u' to cancel)"))
(elpher-get-selector search-address
(lambda (proc event)
(unless (string-prefix-p "deleted" event)
(elpher-with-clean-buffer
(elpher-insert-index elpher-selector-string))
(goto-char (point-min))
- (elpher-set-node-content elpher-current-node
- (buffer-string))))))
+ (elpher-cache-content
+ (elpher-node-address elpher-current-node)
+ (buffer-string))))))
(if aborted
(elpher-visit-parent-node))))))
(defun elpher-get-node-raw ()
"Getter which retrieves the raw server response for the current node."
- (let* ((content (elpher-node-content elpher-current-node))
- (address (elpher-node-address elpher-current-node)))
+ (let ((address (elpher-node-address elpher-current-node)))
(elpher-with-clean-buffer
- (insert "LOADING RAW SERVER RESPONSE..."))
+ (insert "LOADING RAW SERVER RESPONSE... (use 'u' to cancel)"))
(if address
(elpher-get-selector address
(lambda (proc event)
"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
+(defun elpher-insert-rendered-html (string)
+ "Use shr to insert rendered view of html STRING into current buffer."
+ (let ((dom (with-temp-buffer
+ (insert string)
+ (libxml-parse-html-region (point-min) (point-max)))))
+ (shr-insert-document dom)))
+
(defun elpher-get-url-node ()
"Getter which attempts to open the URL specified by the current node."
(let* ((address (elpher-node-address elpher-current-node))
(selector (elpher-address-selector address)))
- (elpher-visit-parent-node) ; Do first in case of non-local exits.
(let ((url (elt (split-string selector "URL:") 1)))
- (if elpher-open-urls-with-eww
- (browse-web url)
- (browse-url url)))))
+ (if url
+ (progn
+ (elpher-visit-parent-node) ; Do first in case of non-local exits.
+ (message "Opening URL...")
+ (if elpher-open-urls-with-eww
+ (browse-web url)
+ (browse-url url)))
+ (let ((content (elpher-get-cached-content address)))
+ (if content
+ (progn
+ (elpher-with-clean-buffer
+ (insert content)
+ (elpher-restore-pos)))
+ (elpher-with-clean-buffer
+ (insert "LOADING HTML... (use 'u' to cancel)"))
+ (elpher-get-selector address
+ (lambda (proc event)
+ (unless (string-prefix-p "deleted" event)
+ (elpher-with-clean-buffer
+ (elpher-insert-rendered-html elpher-selector-string)
+ (goto-char (point-min))
+ (elpher-cache-content
+ (elpher-node-address elpher-current-node)
+ (buffer-string))))))))))))
;; Telnet node connection
(elpher-visit-parent-node)
(telnet host port)))
+;; Start page node retrieval
+
+(defun elpher-get-start-node ()
+ "Getter which displays the start page."
+ (elpher-with-clean-buffer
+ (elpher-insert-index elpher-start-index)
+ (elpher-restore-pos)))
+
+;; Bookmarks page node retrieval
+
+(defun elpher-get-bookmarks-node ()
+ "Getter to load and display the current bookmark list."
+ (elpher-with-clean-buffer
+ (insert "---- Bookmark list ----\n\n")
+ (let ((bookmarks (elpher-load-bookmarks)))
+ (if bookmarks
+ (dolist (bookmark bookmarks)
+ (let ((display-string (elpher-bookmark-display-string bookmark))
+ (address (elpher-bookmark-address bookmark)))
+ (elpher-insert-index-record display-string address)))
+ (insert "No bookmarks found.\n")))
+ (insert "\n-----------------------\n\n"
+ "- u: return to previous page\n"
+ "- x: delete selected bookmark\n"
+ "- a: rename selected bookmark\n\n"
+ "Bookmarks are stored in the file "
+ (locate-user-emacs-file "elpher-bookmarks"))
+ (elpher-restore-pos)))
+
;;; Bookmarks
;;
"Get the display string of BOOKMARK."
(elt bookmark 0))
+(defun elpher-set-bookmark-display-string (bookmark display-string)
+ "Set the display string of BOOKMARK to DISPLAY-STRING."
+ (setcar bookmark display-string))
+
(defun elpher-bookmark-address (bookmark)
"Get the address for BOOKMARK."
(elt bookmark 1))
Beware that this completely replaces the existing contents of the file."
(with-temp-file (locate-user-emacs-file "elpher-bookmarks")
(erase-buffer)
+ (insert "; Elpher gopher bookmarks file\n\n"
+ "; Bookmarks are stored as a list of (label (type selector host port))\n"
+ "; s-expressions, where type is stored as a character (i.e. 49 = ?1).\n"
+ "; Feel free to edit by hand, but ensure this structure remains intact.\n\n")
(pp bookmarks (current-buffer))))
(defun elpher-load-bookmarks ()
(goto-char (point-min))
(read (current-buffer)))))
-(defun elpher-add-node-bookmark (node)
- "Add bookmark to NODE to the saved list of bookmarks."
- (let ((bookmark (elpher-make-bookmark (elpher-node-display-string node)
- (elpher-node-address node)))
- (bookmarks (elpher-load-bookmarks)))
- (add-to-list 'bookmarks bookmark)
+(defun elpher-add-address-bookmark (address display-string)
+ "Save a bookmark for ADDRESS with label DISPLAY-STRING.
+If ADDRESS is already bookmarked, update the label only."
+ (let ((bookmarks (elpher-load-bookmarks)))
+ (let ((existing-bookmark (rassoc (list address) bookmarks)))
+ (if existing-bookmark
+ (elpher-set-bookmark-display-string existing-bookmark display-string)
+ (add-to-list 'bookmarks (elpher-make-bookmark display-string address))))
(elpher-save-bookmarks bookmarks)))
-(defun elpher-remove-node-bookmark (node)
- "Remove bookmark to NODE from the saved list of bookmarks."
- (let ((bookmark (elpher-make-bookmark (elpher-node-display-string node)
- (elpher-node-address node))))
+(defun elpher-remove-address-bookmark (address)
+ "Remove any bookmark to ADDRESS."
(elpher-save-bookmarks
- (seq-filter (lambda (this-bookmark)
- (not (equal bookmark this-bookmark)))
- (elpher-load-bookmarks)))))
-
-(defun elpher-display-bookmarks ()
- "Display saved bookmark list."
- (interactive)
- (elpher-with-clean-buffer
- (insert "Use 'r' to return to the previous page.\n\n"
- "---- Bookmark list ----\n\n")
- (let ((bookmarks (elpher-load-bookmarks)))
- (if bookmarks
- (dolist (bookmark bookmarks)
- (let ((display-string (elpher-bookmark-display-string bookmark))
- (address (elpher-bookmark-address bookmark)))
- (elpher-insert-index-record-helper display-string
- (elpher-address-type address)
- (elpher-address-selector address)
- (elpher-address-host address)
- (elpher-address-port address))))
- (insert "No bookmarks found.\n")))
- (insert "\n-----------------------")
- (goto-char (point-min))
- (elpher-next-link)))
-
-(defun elpher-bookmark-current ()
- "Bookmark the current node."
- (interactive)
- (elpher-add-node-bookmark elpher-current-node))
-
-(defun elpher-bookmark-link ()
- "Bookmark the link at point."
- (interactive)
- (let ((button (button-at (point))))
- (if button
- (elpher-add-node-bookmark (button-get button 'elpher-node))
- (error "No link selected"))))
+ (seq-filter (lambda (bookmark)
+ (not (equal (elpher-bookmark-address bookmark) address)))
+ (elpher-load-bookmarks))))
-(defun elpher-unbookmark-current ()
- "Remove bookmark for the current node."
- (interactive)
- (elpher-remove-node-bookmark elpher-current-node))
-
-(defun elpher-unbookmark-link ()
- "Remove bookmark for the link at point."
- (interactive)
- (let ((button (button-at (point))))
- (if button
- (elpher-remove-node-bookmark (button-get button 'elpher-node))
- (error "No link selected"))))
-
-;;; Interactive navigation procedures
+;;; Interactive procedures
;;
(defun elpher-next-link ()
(push-button))
(defun elpher-go ()
- "Go to a particular gopher site."
+ "Go to a particular gopher site read from the minibuffer.
+The site may be specified via a URL or explicitly in terms of
+host, selector and port."
(interactive)
(let ((node
(let ((host-or-url (read-string "Gopher host or URL: ")))
(if (string-match elpher-url-regex host-or-url)
- (elpher-make-node-from-matched-url elpher-current-node
- host-or-url)
+ (elpher-make-node-from-matched-url host-or-url)
(let ((selector (read-string "Selector (default none): " nil nil ""))
- (port (string-to-number (read-string "Port (default 70): "
- nil nil 70))))
+ (port-string (read-string "Port (default 70): " nil nil "70")))
(elpher-make-node (concat "gopher://" host-or-url
- ":" port
+ ":" port-string
"/1" selector)
- elpher-current-node
- (elpher-make-address ?1 selector host-or-url port)))))))
+ (elpher-make-address ?1 selector host-or-url
+ (string-to-number port-string))))))))
(switch-to-buffer "*elpher*")
(elpher-visit-node node)))
-(defun elpher-redraw ()
+(defun elpher-redraw ()
"Redraw current page."
(interactive)
(if elpher-current-node
(elpher-visit-node elpher-current-node)
(message "No current site.")))
-(defun elpher-reload ()
+(defun elpher-reload ()
"Reload current page."
(interactive)
(if elpher-current-node
(elpher-reload-current-node)
(message "No current site.")))
+(defun elpher-toggle-tls ()
+ "Toggle TLS encryption mode."
+ (interactive)
+ (setq elpher-use-tls (not elpher-use-tls))
+ (if elpher-use-tls
+ (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 ()
- "View current page as plain text."
+ "View raw server response for current page."
(interactive)
(if elpher-current-node
- (elpher-visit-node elpher-current-node
- #'elpher-get-node-raw)
+ (if (elpher-address-special-p (elpher-node-address elpher-current-node))
+ (error "This page was not generated by a server")
+ (elpher-visit-node elpher-current-node
+ #'elpher-get-node-raw))
(message "No current site.")))
(defun elpher-back ()
(let ((button (button-at (point))))
(if button
(let ((node (button-get button 'elpher-node)))
- (if node
- (elpher-visit-node (button-get button 'elpher-node)
- #'elpher-get-node-download)
- (error "Can only download gopher links, not general URLs")))
+ (if (elpher-address-special-p (elpher-node-address node))
+ (error "Cannot download this link")
+ (elpher-visit-node (button-get button 'elpher-node)
+ #'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)
(setq b (next-button (button-start b))))
link-map))
-(defun elpher-menu ()
+(defun elpher-jump ()
"Select a directory entry by name. Similar to the info browser (m)enu command."
(interactive)
(let* ((link-map (elpher-build-link-map)))
(if link-map
(let ((key (let ((completion-ignore-case t))
- (completing-read "Directory entry/link (tab to autocomplete): "
+ (completing-read "Directory item/link: "
link-map nil t))))
(if (and key (> (length key) 0))
(let ((b (cdr (assoc key link-map))))
(defun elpher-root-dir ()
"Visit root of current server."
(interactive)
- (let ((address (elpher-node-address elpher-current-node)))
- (if address
+ (let* ((address (elpher-node-address elpher-current-node))
+ (host (elpher-address-host address)))
+ (if host
(let ((host (elpher-address-host address))
(selector (elpher-address-selector address))
(port (elpher-address-port address)))
(elpher-make-node (concat "gopher://" host
":" (number-to-string port)
"/1/")
- elpher-current-node
root-address)))
(error "Already at root directory of current server")))
- (error "Command invalid for Elpher start page"))))
+ (error "Command invalid for this page"))))
+
+(defun elpher-bookmarks-current-p ()
+ "Return non-nil if current node is a bookmarks page."
+ (eq (elpher-address-type (elpher-node-address elpher-current-node)) 'bookmarks))
+
+(defun elpher-reload-bookmarks ()
+ "Reload bookmarks if current node is a bookmarks page."
+ (if (elpher-bookmarks-current-p)
+ (elpher-reload-current-node)))
+
+(defun elpher-bookmark-current ()
+ "Bookmark the current node."
+ (interactive)
+ (let ((address (elpher-node-address elpher-current-node))
+ (display-string (elpher-node-display-string elpher-current-node)))
+ (if (not (elpher-address-special-p address))
+ (let ((bookmark-display-string (read-string "Bookmark display string: "
+ display-string)))
+ (elpher-add-address-bookmark address bookmark-display-string)
+ (message "Bookmark added."))
+ (error "Cannot bookmark %s" display-string))))
+
+(defun elpher-bookmark-link ()
+ "Bookmark the link at point."
+ (interactive)
+ (let ((button (button-at (point))))
+ (if button
+ (let* ((node (button-get button 'elpher-node))
+ (address (elpher-node-address node))
+ (display-string (elpher-node-display-string node)))
+ (if (not (elpher-address-special-p address))
+ (let ((bookmark-display-string (read-string "Bookmark display string: "
+ display-string)))
+ (elpher-add-address-bookmark address bookmark-display-string)
+ (elpher-reload-bookmarks)
+ (message "Bookmark added."))
+ (error "Cannot bookmark %s" display-string)))
+ (error "No link selected"))))
+
+(defun elpher-unbookmark-current ()
+ "Remove bookmark for the current node."
+ (interactive)
+ (let ((address (elpher-node-address elpher-current-node)))
+ (unless (elpher-address-special-p address)
+ (elpher-remove-address-bookmark address)
+ (message "Bookmark removed."))))
+
+(defun elpher-unbookmark-link ()
+ "Remove bookmark for the link at point."
+ (interactive)
+ (let ((button (button-at (point))))
+ (if button
+ (let ((node (button-get button 'elpher-node)))
+ (elpher-remove-address-bookmark (elpher-node-address node))
+ (elpher-reload-bookmarks)
+ (message "Bookmark removed."))
+ (error "No link selected"))))
+
+(defun elpher-bookmarks ()
+ "Visit bookmarks page."
+ (interactive)
+ (switch-to-buffer "*elpher*")
+ (elpher-visit-node
+ (elpher-make-node "Bookmarks Page" (elpher-make-address 'bookmarks))))
(defun elpher-info-node (node)
"Display information on NODE."
(let ((display-string (elpher-node-display-string node))
(address (elpher-node-address node)))
- (if address
+ (if (not (elpher-address-special-p address))
(message "`%s' on %s port %s"
(elpher-address-selector address)
(elpher-address-host address)
(defun elpher-get-address-url (address)
"Get URL representation of ADDRESS."
- (concat "gopher://"
- (elpher-address-host address)
- (let ((port (elpher-address-port address)))
- (if (equal port 70)
- ""
- (format ":%d" port)))
- "/" (string (elpher-address-type address))
- (elpher-address-selector address)))
+ (let ((type (elpher-address-type address))
+ (selector (elpher-address-selector address))
+ (host (elpher-address-host address))
+ (port (elpher-address-port address)))
+ (if (and (equal type ?h)
+ (string-prefix-p "URL:" selector))
+ (elt (split-string selector "URL:") 1)
+ (concat "gopher"
+ (if (elpher-address-use-tls-p address) "s" "")
+ "://"
+ host
+ (if (equal port 70)
+ ""
+ (format ":%d" port))
+ "/" (string type)
+ selector))))
(defun elpher-copy-node-url (node)
"Copy URL representation of address of NODE to `kill-ring'."
(let ((address (elpher-node-address node)))
- (if address
- (let ((url (elpher-get-address-url address)))
- (message url)
- (kill-new url))
- (error (format "Cannot represent %s as URL" (elpher-node-display-string node))))))
+ (if (elpher-address-special-p address)
+ (error (format "Cannot represent %s as URL" (elpher-node-display-string node)))
+ (let ((url (elpher-get-address-url address)))
+ (message "Copied \"%s\" to kill-ring/clipboard." url)
+ (kill-new url)))))
(defun elpher-copy-link-url ()
"Copy URL of item at point to `kill-ring'."
(interactive)
(elpher-copy-node-url elpher-current-node))
+(defun elpher-set-coding-system ()
+ "Specify an explicit character coding system."
+ (interactive)
+ (let ((system (read-coding-system "Set coding system to use (default is to autodetect): " nil)))
+ (setq elpher-user-coding-system system)
+ (if system
+ (message "Coding system fixed to %s. (Reload to see effect)." system)
+ (message "Coding system set to autodetect. (Reload to see effect)."))))
+
;;; Mode and keymap
;;
(define-key map (kbd "g") 'elpher-go)
(define-key map (kbd "r") 'elpher-redraw)
(define-key map (kbd "R") 'elpher-reload)
+ (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 "m") 'elpher-menu)
+ (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)
(define-key map (kbd "c") 'elpher-copy-link-url)
(define-key map (kbd "C") 'elpher-copy-current-url)
+ (define-key map (kbd "a") 'elpher-bookmark-link)
+ (define-key map (kbd "A") 'elpher-bookmark-current)
+ (define-key map (kbd "x") 'elpher-unbookmark-link)
+ (define-key map (kbd "X") 'elpher-unbookmark-current)
+ (define-key map (kbd "B") 'elpher-bookmarks)
+ (define-key map (kbd "S") 'elpher-set-coding-system)
(when (fboundp 'evil-define-key)
(evil-define-key 'motion map
(kbd "TAB") 'elpher-next-link
(kbd "g") 'elpher-go
(kbd "r") 'elpher-redraw
(kbd "R") 'elpher-reload
+ (kbd "T") 'elpher-toggle-tls
(kbd "w") 'elpher-view-raw
(kbd "d") 'elpher-download
- (kbd "m") 'elpher-menu
+ (kbd "D") 'elpher-download-current
+ (kbd "m") 'elpher-jump
(kbd "i") 'elpher-info-link
(kbd "I") 'elpher-info-current
(kbd "c") 'elpher-copy-link-url
(kbd "A") 'elpher-bookmark-current
(kbd "x") 'elpher-unbookmark-link
(kbd "X") 'elpher-unbookmark-current
- (kbd "B") 'elpher-display-bookmarks))
+ (kbd "B") 'elpher-bookmarks
+ (kbd "S") 'elpher-set-coding-system))
map)
"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))
(switch-to-buffer "*elpher*")
(setq elpher-current-node nil)
(let ((start-node (elpher-make-node "Elpher Start Page"
- nil elpher-start-address)))
+ (elpher-make-address 'start))))
(elpher-visit-node start-node)))
"Started Elpher.") ; Otherwise (elpher) evaluates to start page string.
The Lambda Lab / projects / elpher.git / blobdiff