X-Git-Url: https://thelambdalab.xyz/gitweb/index.cgi?p=elpher.git;a=blobdiff_plain;f=elpher.el;h=1fa5ed54ea7291bcd8cc8e12c60c5e93ed2168c0;hp=25d8238660b44b418837e05607feec8b6fbdc0a2;hb=5df0f96c23837284d585c8917744584f70a63c7f;hpb=9ea621716fd8258c7493e6712161807b59455aa2 diff --git a/elpher.el b/elpher.el index 25d8238..1fa5ed5 100644 --- a/elpher.el +++ b/elpher.el @@ -1,13 +1,13 @@ -;;; elpher.el --- Full-featured gopher client. +;;; elpher.el --- A friendly gopher client. ;; Copyright (C) 2019 Tim Vaughan ;; Author: Tim Vaughan ;; Created: 11 April 2019 -;; Version: 1.1.0 +;; Version: 1.4.7 ;; Keywords: comm gopher ;; Homepage: https://github.com/tgvaughan/elpher -;; Package-Requires: ((emacs "25")) +;; Package-Requires: ((emacs "26")) ;; This file is not part of GNU Emacs. @@ -26,94 +26,67 @@ ;;; 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 interface, -;; - caching of visited sites (both content and cursor position), +;; - intuitive keyboard and mouse-driven browsing, +;; - out-of-the-box compatibility with evil-mode, +;; - clickable web and gopher links *in plain text*, +;; - caching of visited sites, ;; - 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, +;; - connections using TLS encryption. ;; 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. +;; Full instructions can be found in the Elpher info manual. + +;; Elpher is under active development. Any suggestions for +;; improvements are welcome! ;;; Code: (provide 'elpher) + +;;; Dependencies +;; + (require 'seq) (require 'pp) +(require 'shr) +(require 'url-util) + ;;; Global constants ;; -(defconst elpher-version "1.1.0" +(defconst elpher-version "2.0.0" "Current version of elpher.") (defconst elpher-margin-width 6 "Width of left-hand margin used when rendering indicies.") -(defconst elpher-start-index - (mapconcat - 'identity - (list "i\tfake\tfake\t1" - "i --------------------------------------------\tfake\tfake\t1" - "i Elpher Gopher Client \tfake\tfake\t1" - (format "i version %s\tfake\tfake\t1" elpher-version) - "i --------------------------------------------\tfake\tfake\t1" - "i\tfake\tfake\t1" - "iUsage:\tfake\tfake\t1" - "i\tfake\tfake\t1" - "i - tab/shift-tab: next/prev item on current page\tfake\tfake\t1" - "i - RET/mouse-1: open item under cursor\tfake\tfake\t1" - "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 - 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 - w: display the raw server response for the current page\tfake\tfake\t1" - "i\tfake\tfake\t1" - "iWhere to start exploring Gopherspace:\tfake\tfake\t1" - "i\tfake\tfake\t1" - "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" - "i\tfake\tfake\t1" - "7Veronica-2 Gopher Search Engine\t/v2/vs\tgopher.floodgap.com\t70" - ".\r\n") - "\r\n") - "Source for elpher start page.") - (defconst elpher-type-map - '((?0 elpher-get-text-node "T" 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) - (?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) - (bookmarks elpher-get-bookmarks-node "#" elpher-index) - (start elpher-get-start-node "#" elpher-index)) + '(((gopher ?0) elpher-get-text-node "txt" elpher-text) + ((gopher ?1) elpher-get-index-node "/" elpher-index) + ((gopher ?4) elpher-get-node-download "bin" elpher-binary) + ((gopher ?5) elpher-get-node-download "bin" elpher-binary) + ((gopher ?7) elpher-get-search-node "?" elpher-search) + ((gopher ?8) elpher-get-telnet-node "tel" elpher-telnet) + ((gopher ?9) elpher-get-node-download "bin" elpher-binary) + ((gopher ?g) elpher-get-image-node "img" elpher-image) + ((gopher ?p) elpher-get-image-node "img" elpher-image) + ((gopher ?I) elpher-get-image-node "img" elpher-image) + ((gopher ?d) elpher-get-node-download "doc" elpher-binary) + ((gopher ?P) elpher-get-node-download "doc" elpher-binary) + ((gopher ?s) elpher-get-node-download "snd" elpher-binary) + ((gopher ?h) elpher-get-html-node "htm" elpher-html) + (other-url elpher-get-other-url-node "url" elpher-other-url) + ((special bookmarks) elpher-get-bookmarks-node) + ((special start) elpher-get-start-node)) "Association list from types to getters, margin codes and index faces.") @@ -146,7 +119,11 @@ '((t :inherit warning)) "Face used for search type directory records.") -(defface elpher-url +(defface elpher-html + '((t :inherit font-lock-comment-face)) + "Face used for url type directory records.") + +(defface elpher-other-url '((t :inherit font-lock-comment-face)) "Face used for url type directory records.") @@ -181,64 +158,151 @@ Otherwise, use the system browser via the BROWSE-URL function." "If non-nil, turns URLs matched in directories into clickable buttons." :type '(boolean)) -(defcustom elpher-cache-images nil - "If non-nil, cache images in memory in the same way as other content." - :type '(boolean)) - (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 &optional selector host port) - "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." - (list type selector host port)) +;; An elpher "address" object is either a url object or a symbol. +;; Symbol addresses are "special", corresponding to pages generated +;; dynamically for and by elpher. All others represent pages which +;; rely on content retrieved over the network. + +(defun elpher-address-from-url (url-string) + "Create a ADDRESS object corresponding to the given URL-STRING." + (let ((data (match-data))) ; Prevent parsing clobbering match data + (unwind-protect + (let ((url (url-generic-parse-url url-string))) + (setf (url-fullness url) t) + (unless (url-host url) + (setf (url-host url) (url-filename url)) + (setf (url-filename url) "")) + (unless (url-type url) + (setf (url-type url) "gopher")) + (if (and (url-type url) + (url-host url)) + (let ((is-gopher (or (equal "gopher" (url-type url)) + (equal "gophers" (url-type url))))) + (setf (url-filename url) + (url-unhex-string (url-filename url))) + (when (or (equal (url-filename url) "") + (equal (url-filename url) "/")) + (if is-gopher + (setf (url-filename url) "/1"))) + (unless (> (url-port url) 0) + (if is-gopher + (setf (url-port url) 70))) + url) + (error "Malformed URL" url))) + (set-match-data data)))) + +(defun elpher-make-gopher-address (type selector host port &optional tls) + "Create an ADDRESS object corresponding to the given gopher directory record +attributes: TYPE, SELECTOR, HOST and PORT." + (if (and (equal type ?h) + (string-prefix-p "URL:" selector)) + (elpher-address-from-url (elt (split-string selector "URL:") 1)) + (elpher-address-from-url + (concat "gopher" (if tls "s" "") + "://" host + ":" (number-to-string port) + "/" (string type) + selector)))) + +(defun elpher-make-special-address (type) + "Create an ADDRESS object corresponding to the given special page symbol TYPE." + type) + +(defun elpher-address-to-url (address) + "Get string representation of ADDRESS, or nil if ADDRESS is special." + (if (not (elpher-address-special-p address)) + (url-encode-url (url-recreate-url address)) + nil)) (defun elpher-address-type (address) - "Retrieve type from ADDRESS." - (elt address 0)) - -(defun elpher-address-selector (address) - "Retrieve selector from ADDRESS." - (elt address 1)) + "Retrieve selector type from ADDRESS object." + (if (symbolp address) + (list 'special address) + (let ((protocol (url-type address))) + (cond ((or (equal protocol "gopher") + (equal protocol "gophers")) + (list 'gopher (string-to-char (substring (url-filename address) 1)))) + ((equal protocol "gemini") + 'gemini) + (t 'other-url))))) + +(defun elpher-address-protocol (address) + (if (symbolp address) + nil + (url-type address))) + +(defun elpher-address-filename (address) + (if (symbolp address) + nil + (url-filename address))) (defun elpher-address-host (address) - "Retrieve host from ADDRESS." - (elt address 2)) + "Retrieve host from ADDRESS object." + (url-host address)) (defun elpher-address-port (address) - "Retrieve port from ADDRESS." - (elt address 3)) + "Retrieve port from ADDRESS object." + (url-port address)) + +(defun elpher-address-special-p (address) + "Return non-nil if ADDRESS object is special (e.g. start page, bookmarks page)." + (symbolp address)) + +(defun elpher-address-gopher-p (address) + "Return non-nill if ADDRESS object is a gopher address." + (memq (elpher-address-protocol address) '("gopher gophers"))) + +(defun elpher-gopher-address-selector (address) + "Retrieve gopher selector from ADDRESS object." + (substring (url-filename address) 2)) ;; Node -(defun elpher-make-node (display-string parent address) - "Create a node in the gopher page hierarchy. +(defun elpher-make-node (display-string address &optional parent) + "Create a node in the 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." - (list display-string parent address)) +ADDRESS specifies the address object of the page. + +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." +(defun elpher-node-address (node) + "Retrieve the ADDRESS object of NODE." (elt node 1)) -(defun elpher-node-address (node) - "Retrieve the address of NODE." +(defun elpher-node-parent (node) + "Retrieve the parent node of NODE." (elt node 2)) +(defun elpher-set-node-parent (node parent) + "Set the parent node of NODE to be PARENT." + (setcar (cdr (cdr node)) parent)) + ;; Cache (defvar elpher-content-cache (make-hash-table :test 'equal)) @@ -264,22 +328,40 @@ address of the gopher page." (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) (if getter (funcall getter) (let* ((address (elpher-node-address node)) - (type (elpher-address-type address))) - (funcall (car (alist-get type elpher-type-map)))))) + (type (elpher-address-type address)) + (type-record (cdr (assoc type elpher-type-map)))) + (if type-record + (funcall (car type-record)) + (elpher-visit-parent-node) + (pcase type + (`(gopher ,type-char) + (error "Unsupported gopher selector type '%c' for '%s'" + type-char (elpher-address-to-url address))) + (else + (error "Unsupported address type '%S' for '%s'" + type (elpher-address-to-url address)))))))) (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." @@ -317,14 +399,29 @@ address of the gopher page." args))) -;;; Index rendering +;;; 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) - "Clear away CRs and terminating period from STRING." - (replace-regexp-in-string "\n\.\n$" "\n" - (replace-regexp-in-string "\r" "" - string))) + "Preprocess text selector response contained in STRING. +This involes decoding the character representation, and clearing +away CRs and any terminating period." + (elpher-decode (replace-regexp-in-string "\n\.\n$" "\n" + (replace-regexp-in-string "\r" "" string)))) + + +;;; Index rendering +;; (defun elpher-insert-index (string) "Insert the index corresponding to STRING into the current buffer." @@ -340,8 +437,9 @@ address of the gopher page." (host (elt fields 2)) (port (if (elt fields 3) (string-to-number (elt fields 3)) - nil))) - (elpher-insert-index-record display-string type selector host port)))))) + nil)) + (address (elpher-make-gopher-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." @@ -358,24 +456,17 @@ address of the gopher page." (defun elpher-node-button-help (node) "Return a string containing the help text for a button corresponding to NODE." (let ((address (elpher-node-address node))) - (if (eq (elpher-address-type address) ?h) - (let ((url (cadr (split-string (elpher-address-selector address) "URL:")))) - (format "mouse-1, RET: open url '%s'" url)) - (format "mouse-1, RET: open '%s' on %s port %s" - (elpher-address-selector address) - (elpher-address-host address) - (elpher-address-port address))))) - -(defun elpher-insert-index-record (display-string type selector host port) + (format "mouse-1, RET: open '%s'" (elpher-address-to-url 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 TYPE, DISPLAY-STRING, SELECTOR, HOST -and PORT." - (let ((address (elpher-make-address type selector host port)) - (type-map-entry (alist-get type elpher-type-map))) +The contents of the record are dictated by DISPLAY-STRING and ADDRESS." + (let* ((type (elpher-address-type address)) + (type-map-entry (cdr (assoc type elpher-type-map)))) (if type-map-entry - (let* ((margin-code (cadr type-map-entry)) + (let* ((margin-code (elt type-map-entry 1)) (face (elt type-map-entry 2)) - (node (elpher-make-node display-string elpher-current-node address))) + (node (elpher-make-node display-string address))) (elpher-insert-margin margin-code) (insert-text-button display-string 'face face @@ -384,17 +475,17 @@ and PORT." 'follow-link t 'help-echo (elpher-node-button-help node))) (pcase type - (?i ;; Information + ('(gopher ?i) ;; Information (elpher-insert-margin) (insert (propertize (if elpher-buttonify-urls-in-directories (elpher-buttonify-urls display-string) display-string) 'face 'elpher-info))) - (other ;; Unknown - (elpher-insert-margin (concat (char-to-string type) "?")) + (`(gopher ,selector-type) ;; Unknown + (elpher-insert-margin (concat (char-to-string selector-type) "?")) (insert (propertize display-string - 'face 'elpher-unknown-face))))) + 'face 'elpher-unknown))))) (insert "\n"))) (defun elpher-click-link (button) @@ -403,7 +494,7 @@ and PORT." (elpher-visit-node node))) -;;; Selector retrieval (all kinds) +;;; Gopher selector retrieval (all kinds) ;; (defun elpher-process-cleanup () @@ -411,21 +502,59 @@ and PORT." (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 (equal (elpher-address-protocol address) "gophers") + (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-gopher-address-selector address) "\n"))) + (error + (if (and (consp the-error) + (eq (car the-error) 'gnutls-error) + (not (equal (elpher-address-protocol address) "gophers")) + (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-address-to-url address) ".\n" + (propertize "\n----------------\n\n" 'face 'error) + "Press 'u' to return to the previous page."))))))) ;; Index retrieval @@ -439,7 +568,7 @@ The result is stored as a string in the variable ‘elpher-selector-string’." (insert content) (elpher-restore-pos))) (elpher-with-clean-buffer - (insert "LOADING DIRECTORY...")) + (insert "LOADING DIRECTORY... (use 'u' to cancel)")) (elpher-get-selector address (lambda (proc event) (unless (string-prefix-p "deleted" event) @@ -453,48 +582,17 @@ The result is stored as a string in the variable ‘elpher-selector-string’." ;; Text retrieval (defconst elpher-url-regex - "\\([a-zA-Z]+\\)://\\([a-zA-Z0-9.\-]+\\)\\(?3::[0-9]+\\)?\\(?4:/[^ \r\n\t(),]*\\)?" + "\\([a-zA-Z]+\\)://\\([a-zA-Z0-9.\-]+\\|\[[a-zA-Z0-9:]+\]\\)\\(?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) - "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") - (let* ((host (match-string 2 string)) - (port (if (> (length (match-string 3 string)) 1) - (string-to-number (substring (match-string 3 string) 1)) - 70)) - (type-and-selector (match-string 4 string)) - (type (if (> (length type-and-selector) 1) - (elt type-and-selector 1) - ?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)) - (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))))) - - (defun elpher-buttonify-urls (string) "Turn substrings which look like urls in STRING into clickable buttons." (with-temp-buffer (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 (match-string 0) + (elpher-address-from-url (match-string 0))))) (make-text-button (match-beginning 0) (match-end 0) 'elpher-node node @@ -514,7 +612,7 @@ calls, as is necessary if the match is performed by `string-match'." (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) @@ -531,33 +629,21 @@ calls, as is necessary if the match is performed by `string-match'." (defun elpher-get-image-node () "Getter which retrieves the current node contents as an image to view." - (let* ((address (elpher-node-address elpher-current-node)) - (content (elpher-get-cached-content address))) - (if content + (let* ((address (elpher-node-address elpher-current-node))) + (if (display-images-p) (progn (elpher-with-clean-buffer - (insert-image content) - (elpher-restore-pos))) - (if (display-images-p) - (progn - (elpher-with-clean-buffer - (insert "LOADING IMAGE...")) - (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) - nil t))) - (elpher-with-clean-buffer - (insert-image image) - (elpher-restore-pos)) - (if elpher-cache-images - (elpher-cache-content - (elpher-node-address elpher-current-node) - image))))))) - (elpher-get-node-download))))) + (insert "LOADING IMAGE... (use 'u' to cancel)")) + (elpher-get-selector address + (lambda (proc event) + (unless (string-prefix-p "deleted" event) + (let ((image (create-image + elpher-selector-string + nil t))) + (elpher-with-clean-buffer + (insert-image image) + (elpher-restore-pos))))))) + (elpher-get-node-download)))) ;; Search retrieval @@ -574,14 +660,14 @@ calls, as is necessary if the match is performed by `string-match'." (message "Displaying cached search results. Reload to perform a new search.")) (unwind-protect (let* ((query-string (read-string "Query: ")) - (query-selector (concat (elpher-address-selector address) "\t" query-string)) - (search-address (elpher-make-address ?1 + (query-selector (concat (elpher-gopher-address-selector address) "\t" query-string)) + (search-address (elpher-make-gopher-address ?1 query-selector (elpher-address-host address) (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) @@ -600,18 +686,13 @@ calls, as is necessary if the match is performed by `string-match'." "Getter which retrieves the raw server response for the current node." (let ((address (elpher-node-address elpher-current-node))) (elpher-with-clean-buffer - (insert "LOADING RAW SERVER RESPONSE...")) - (if address - (elpher-get-selector address - (lambda (proc event) - (unless (string-prefix-p "deleted" event) - (elpher-with-clean-buffer - (insert elpher-selector-string) - (goto-char (point-min)))))) - (progn - (elpher-with-clean-buffer - (insert elpher-start-index)) - (goto-char (point-min))))) + (insert "LOADING RAW SERVER RESPONSE... (use 'u' to cancel)")) + (elpher-get-selector address + (lambda (proc event) + (unless (string-prefix-p "deleted" event) + (elpher-with-clean-buffer + (insert elpher-selector-string) + (goto-char (point-min))))))) (message "Displaying raw server response. Reload or redraw to return to standard view.")) ;; File export retrieval @@ -621,7 +702,7 @@ calls, as is necessary if the match is performed by `string-match'." (defun elpher-get-node-download () "Getter which retrieves the current node and writes the result to a file." (let* ((address (elpher-node-address elpher-current-node)) - (selector (elpher-address-selector address))) + (selector (elpher-gopher-address-selector address))) (elpher-visit-parent-node) ; Do first in case of non-local exits. (let* ((filename-proposal (file-name-nondirectory selector)) (filename (read-file-name "Save file as: " @@ -631,22 +712,59 @@ calls, as is necessary if the match is performed by `string-match'." "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)))))) + +;; HTML node 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-html-node () + "Getter which retrieves and renders an HTML node." + (let* ((address (elpher-node-address elpher-current-node)) + (selector (elpher-gopher-address-selector address))) + (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)))))))))) + -;; URL retrieval +;; Other URL node opening -(defun elpher-get-url-node () +(defun elpher-get-other-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))) + (url (elpher-address-to-url address))) + (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))))) @@ -666,39 +784,85 @@ calls, as is necessary if the match is performed by `string-match'." (defun elpher-get-start-node () "Getter which displays the start page." (elpher-with-clean-buffer - (elpher-insert-index elpher-start-index) + (insert " --------------------------------------------\n" + " Elpher Gopher Client \n" + " version " elpher-version "\n" + " --------------------------------------------\n" + "\n" + "Default bindings:\n" + "\n" + " - TAB/Shift-TAB: next/prev item on current page\n" + " - RET/mouse-1: open item under cursor\n" + " - m: select an item on current page by name (autocompletes)\n" + " - u: return to previous page\n" + " - o/O: visit different selector or the root menu of the current server\n" + " - g: go to a particular gopher address\n" + " - i/I: info on item under cursor or current page\n" + " - c/C: copy URL representation of item under cursor or current page\n" + " - a/A: bookmark the item under cursor or current page\n" + " - x/X: remove bookmark for item under cursor or current page\n" + " - B: visit the bookmarks page\n" + " - r: redraw current page (using cached contents if available)\n" + " - R: reload current page (regenerates cache)\n" + " - T: toggle TLS mode\n" + " - d/D: download item under cursor or current page\n" + " - .: display the raw server response for the current page\n" + " - S: set an explicit character coding system (default is to autodetect)\n" + "\n" + "Start your exploration of gopher space:\n") + (elpher-insert-index-record "Floodgap Systems Gopher Server" + (elpher-make-gopher-address ?1 "" "gopher.floodgap.com" 70)) + (insert "\n" + "Alternatively, select the following item and enter some search terms:\n") + (elpher-insert-index-record "Veronica-2 Gopher Search Engine" + (elpher-make-gopher-address ?7 "/v2/vs" "gopher.floodgap.com" 70)) + (insert "\n" + "** Refer to the ") + (let ((help-string "RET,mouse-1: Open Elpher info manual (if available)")) + (insert-text-button "Elpher info manual" + 'face 'link + 'action (lambda (button) + (interactive) + (info "(elpher)")) + 'follow-link t + 'help-echo help-string)) + (insert " for the full documentation. **\n") + (insert (propertize + (concat " (This should be available if you have installed Elpher using\n" + " MELPA. Otherwise you will have to install the manual yourself.)") + 'face 'shadow)) (elpher-restore-pos))) ;; Bookmarks page node retrieval (defun elpher-get-bookmarks-node () - "Getter which loads and displays the current bookmark list." + "Getter to load and display the current bookmark list." (elpher-with-clean-buffer - (insert "Use 'u' to return to the previous page.\n\n" - "---- Bookmark list ----\n\n") + (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 - (elpher-address-type address) - (elpher-address-selector address) - (elpher-address-host address) - (elpher-address-port address)))) + (address (elpher-address-from-url (elpher-bookmark-url bookmark)))) + (elpher-insert-index-record display-string address))) (insert "No bookmarks found.\n"))) - (insert "\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 ;; -(defun elpher-make-bookmark (display-string address) +(defun elpher-make-bookmark (display-string url) "Make an elpher bookmark. DISPLAY-STRING determines how the bookmark will appear in the bookmark list, while ADDRESS is the address of the entry." - (list display-string address)) + (list display-string (elpher-address-to-url address))) (defun elpher-bookmark-display-string (bookmark) "Get the display string of BOOKMARK." @@ -708,41 +872,48 @@ bookmark list, while ADDRESS is the address of the entry." "Set the display string of BOOKMARK to DISPLAY-STRING." (setcar bookmark display-string)) -(defun elpher-bookmark-address (bookmark) +(defun elpher-bookmark-url (bookmark) "Get the address for BOOKMARK." (elt bookmark 1)) + (defun elpher-save-bookmarks (bookmarks) "Record the bookmark list BOOKMARKS to the user's bookmark file. Beware that this completely replaces the existing contents of the file." - (with-temp-file (locate-user-emacs-file "elpher-bookmarks") + (with-temp-file (locate-user-emacs-file "elpher2-bookmarks") (erase-buffer) + (insert "; Elpher bookmarks file\n\n" + "; Bookmarks are stored as a list of (label URL) items.\n" + "; Feel free to edit by hand, but take care to ensure\n" + "; the list structure remains intact.\n\n") (pp bookmarks (current-buffer)))) (defun elpher-load-bookmarks () "Get the list of bookmarks from the users's bookmark file." (with-temp-buffer (ignore-errors - (insert-file-contents (locate-user-emacs-file "elpher-bookmarks")) + (insert-file-contents (locate-user-emacs-file "elpher2-bookmarks")) (goto-char (point-min)) (read (current-buffer))))) (defun elpher-add-address-bookmark (address display-string) - "Save a bookmark for ADDRESS with label 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))) + (let ((bookmarks (elpher-load-bookmarks)) + (url (elpher-address-to-url address))) + (let ((existing-bookmark (rassoc (list url) bookmarks))) (if existing-bookmark (elpher-set-bookmark-display-string existing-bookmark display-string) - (add-to-list 'bookmarks (elpher-make-bookmark display-string address)))) + (add-to-list 'bookmarks (elpher-make-bookmark display-string url)))) (elpher-save-bookmarks bookmarks))) (defun elpher-remove-address-bookmark (address) "Remove any bookmark to ADDRESS." + (let ((url (elpher-address-to-url address))) (elpher-save-bookmarks (seq-filter (lambda (bookmark) - (not (equal (elpher-bookmark-address bookmark) address))) - (elpher-load-bookmarks)))) + (not (equal (elpher-bookmark-url bookmark) url))) + (elpher-load-bookmarks))))) ;;; Interactive procedures ;; @@ -763,44 +934,59 @@ If ADDRESS is already bookmarked, update the label only." (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) - (let ((selector (read-string "Selector (default none): " nil nil "")) - (port-string (read-string "Port (default 70): " nil nil "70"))) - (elpher-make-node (concat "gopher://" host-or-url - ":" port-string - "/1" selector) - elpher-current-node - (elpher-make-address ?1 selector host-or-url - (string-to-number port-string)))))))) + (elpher-make-node host-or-url + (elpher-address-from-url host-or-url))))) (switch-to-buffer "*elpher*") (elpher-visit-node node))) -(defun elpher-redraw () +(defun elpher-go-current () + "Go to a particular site read from the minibuffer, initialized with the current URL." + (interactive) + (let ((address (elpher-node-address elpher-current-node))) + (if (elpher-address-special-p address) + (error "Command not valid for this page") + (let ((url (read-string "URL: " (elpher-address-to-url address)))) + (elpher-visit-node (elpher-make-node url (elpher-address-from-url url))))))) + +(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 () @@ -816,12 +1002,24 @@ If ADDRESS is already bookmarked, update the label only." (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) @@ -837,7 +1035,7 @@ If ADDRESS is already bookmarked, update the label only." (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)))) @@ -851,22 +1049,19 @@ If ADDRESS is already bookmarked, update the label only." (host (elpher-address-host address))) (if host (let ((host (elpher-address-host address)) - (selector (elpher-address-selector address)) + (selector (elpher-gopher-address-selector address)) (port (elpher-address-port address))) (if (> (length selector) 0) - (let ((root-address (elpher-make-address ?1 "" host port))) + (let ((root-address (elpher-make-gopher-address ?1 "" host port))) (elpher-visit-node - (elpher-make-node (concat "gopher://" host - ":" (number-to-string port) - "/1/") - elpher-current-node - root-address))) + (elpher-make-node (elpher-address-to-url root-address)))) (error "Already at root directory of current server"))) (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)) + (equal (elpher-address-type (elpher-node-address elpher-current-node)) + '(special bookmarks))) (defun elpher-reload-bookmarks () "Reload bookmarks if current node is a bookmarks page." @@ -876,11 +1071,14 @@ If ADDRESS is already bookmarked, update the label only." (defun elpher-bookmark-current () "Bookmark the current node." (interactive) - (if (not (elpher-bookmarks-current-p)) - (let ((address (elpher-node-address elpher-current-node)) - (display-string (read-string "Bookmark display string: " - (elpher-node-display-string elpher-current-node)))) - (elpher-add-address-bookmark address display-string)))) + (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." @@ -889,17 +1087,23 @@ If ADDRESS is already bookmarked, update the label only." (if button (let* ((node (button-get button 'elpher-node)) (address (elpher-node-address node)) - (display-string (read-string "Bookmark display string: " - (elpher-node-display-string node)))) - (elpher-add-address-bookmark address display-string) - (elpher-reload-bookmarks)) + (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) - (if (not (elpher-bookmarks-current-p)) - (elpher-remove-address-bookmark (elpher-node-address elpher-current-node)))) + (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." @@ -908,27 +1112,24 @@ If ADDRESS is already bookmarked, update the label only." (if button (let ((node (button-get button 'elpher-node))) (elpher-remove-address-bookmark (elpher-node-address node)) - (elpher-reload-bookmarks)) + (elpher-reload-bookmarks) + (message "Bookmark removed.")) (error "No link selected")))) (defun elpher-bookmarks () - "Visit bookmarks." + "Visit bookmarks page." (interactive) + (switch-to-buffer "*elpher*") (elpher-visit-node - (elpher-make-node "Bookmarks" - elpher-current-node - (elpher-make-address 'bookmarks)))) + (elpher-make-node "Bookmarks Page" (elpher-make-special-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 - (message "`%s' on %s port %s" - (elpher-address-selector address) - (elpher-address-host address) - (elpher-address-port address)) - (message "%s" display-string)))) + (if (elpher-address-special-p address) + (message "Special page: %s" display-string) + (message (elpher-address-to-url address))))) (defun elpher-info-link () "Display information on node corresponding to link at point." @@ -943,25 +1144,14 @@ If ADDRESS is already bookmarked, update the label only." (interactive) (elpher-info-node elpher-current-node)) -(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))) - (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-address-to-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'." @@ -976,6 +1166,16 @@ If ADDRESS is already bookmarked, update the label only." (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 ;; @@ -986,10 +1186,13 @@ If ADDRESS is already bookmarked, update the label only." (define-key map (kbd "u") 'elpher-back) (define-key map (kbd "O") 'elpher-root-dir) (define-key map (kbd "g") 'elpher-go) + (define-key map (kbd "o") 'elpher-go-current) (define-key map (kbd "r") 'elpher-redraw) (define-key map (kbd "R") 'elpher-reload) - (define-key map (kbd "w") 'elpher-view-raw) + (define-key map (kbd "T") 'elpher-toggle-tls) + (define-key map (kbd ".") '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) @@ -1000,18 +1203,22 @@ If ADDRESS is already bookmarked, update the label only." (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 "C-]") 'elpher-follow-current-link + (kbd "C-") 'elpher-follow-current-link (kbd "C-t") 'elpher-back (kbd "u") 'elpher-back (kbd "O") 'elpher-root-dir (kbd "g") 'elpher-go + (kbd "o") 'elpher-go-current (kbd "r") 'elpher-redraw (kbd "R") 'elpher-reload - (kbd "w") 'elpher-view-raw + (kbd "T") 'elpher-toggle-tls + (kbd ".") '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 @@ -1021,16 +1228,22 @@ If ADDRESS is already bookmarked, update the label only." (kbd "A") 'elpher-bookmark-current (kbd "x") 'elpher-unbookmark-link (kbd "X") 'elpher-unbookmark-current - (kbd "B") 'elpher-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)) + ;;; Main start procedure ;; @@ -1042,7 +1255,8 @@ If ADDRESS is already bookmarked, update the label only." (switch-to-buffer "*elpher*") (switch-to-buffer "*elpher*") (setq elpher-current-node nil) - (let ((start-node (elpher-make-node "Elpher Start Page" nil (elpher-make-address 'start)))) + (let ((start-node (elpher-make-node "Elpher Start Page" + (elpher-make-special-address 'start)))) (elpher-visit-node start-node))) "Started Elpher.") ; Otherwise (elpher) evaluates to start page string.