X-Git-Url: https://thelambdalab.xyz/gitweb/index.cgi?p=elpher.git;a=blobdiff_plain;f=elpher.el;h=75b582bb7d0059e03e52772f603db46f36f892d1;hp=889c79b89383f1f8d799a5ce3e43a7e8aa790339;hb=refs%2Fheads%2Fpatch_multiple_buffers;hpb=bb6fa3a36f8c283d39829bb5adad997b9f9ab3d6 diff --git a/elpher.el b/elpher.el index 889c79b..5b0f132 100644 --- a/elpher.el +++ b/elpher.el @@ -1,13 +1,13 @@ -;;; elpher.el --- A friendly gopher client. +;;; elpher.el --- A friendly gopher and gemini client -*- lexical-binding:t -*- -;; Copyright (C) 2019 Tim Vaughan +;; Copyright (C) 2019-2020 Tim Vaughan -;; Author: Tim Vaughan +;; Author: Tim Vaughan ;; Created: 11 April 2019 -;; Version: 1.4.6 +;; Version: 2.10.0 ;; Keywords: comm gopher -;; Homepage: https://github.com/tgvaughan/elpher -;; Package-Requires: ((emacs "26")) +;; Homepage: http://thelambdalab.xyz/elpher +;; Package-Requires: ((emacs "26.2")) ;; This file is not part of GNU Emacs. @@ -26,8 +26,8 @@ ;;; Commentary: -;; Elpher aims to provide a practical and friendly gopher client -;; for GNU Emacs. It supports: +;; Elpher aims to provide a practical and friendly gopher and gemini +;; client for GNU Emacs. It supports: ;; - intuitive keyboard and mouse-driven browsing, ;; - out-of-the-box compatibility with evil-mode, @@ -36,7 +36,9 @@ ;; - pleasant and configurable colouring of Gopher directories, ;; - direct visualisation of image files, ;; - a simple bookmark management system, -;; - connections using TLS encryption. +;; - gopher connections using TLS encryption, +;; - the fledgling Gemini protocol, +;; - the greybeard Finger protocol. ;; To launch Elpher, simply use 'M-x elpher'. This will open a start ;; page containing information on key bindings and suggested starting @@ -45,7 +47,8 @@ ;; Full instructions can be found in the Elpher info manual. ;; Elpher is under active development. Any suggestions for -;; improvements are welcome! +;; improvements are welcome, and can be made on the official +;; project page, gopher://thelambdalab.xyz/1/projects/elpher/. ;;; Code: @@ -58,47 +61,145 @@ (require 'pp) (require 'shr) (require 'url-util) - +(require 'subr-x) +(require 'dns) +(require 'nsm) +(require 'gnutls) + +;;; ANSI colors or XTerm colors + +(or (require 'xterm-color nil t) + (require 'ansi-color)) + +(defalias 'elpher-color-filter-apply + (if (fboundp 'xterm-color-filter) + (lambda (s) + (let ((xterm-color-render nil)) + (xterm-color-filter s))) + 'ansi-color-filter-apply) + "A function to filter out ANSI escape sequences.") +(defalias 'elpher-color-apply + (if (fboundp 'xterm-color-filter) + 'xterm-color-filter + 'ansi-color-apply) + "A function to apply ANSI escape sequences.") ;;; Global constants ;; -(defconst elpher-version "1.4.6" +(defconst elpher-version "2.10.0" "Current version of elpher.") (defconst elpher-margin-width 6 "Width of left-hand margin used when rendering indicies.") - (defconst elpher-type-map - '((?0 elpher-get-text-node "txt" elpher-text) - (?1 elpher-get-index-node "/" elpher-index) - (?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 "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) - (?P elpher-get-node-download "doc" elpher-binary) - (?s elpher-get-node-download "snd" elpher-binary) - (?h elpher-get-url-node "url" 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.") + '(((gopher ?0) elpher-get-gopher-page elpher-render-text "txt" elpher-text) + ((gopher ?1) elpher-get-gopher-page elpher-render-index "/" elpher-index) + ((gopher ?4) elpher-get-gopher-page elpher-render-download "bin" elpher-binary) + ((gopher ?5) elpher-get-gopher-page elpher-render-download "bin" elpher-binary) + ((gopher ?7) elpher-get-gopher-query-page elpher-render-index "?" elpher-search) + ((gopher ?9) elpher-get-gopher-page elpher-render-download "bin" elpher-binary) + ((gopher ?g) elpher-get-gopher-page elpher-render-image "img" elpher-image) + ((gopher ?p) elpher-get-gopher-page elpher-render-image "img" elpher-image) + ((gopher ?I) elpher-get-gopher-page elpher-render-image "img" elpher-image) + ((gopher ?d) elpher-get-gopher-page elpher-render-download "doc" elpher-binary) + ((gopher ?P) elpher-get-gopher-page elpher-render-download "doc" elpher-binary) + ((gopher ?s) elpher-get-gopher-page elpher-render-download "snd" elpher-binary) + ((gopher ?h) elpher-get-gopher-page elpher-render-html "htm" elpher-html) + (gemini elpher-get-gemini-page elpher-render-gemini "gem" elpher-gemini) + (finger elpher-get-finger-page elpher-render-text "txt" elpher-text) + (telnet elpher-get-telnet-page nil "tel" elpher-telnet) + (other-url elpher-get-other-url-page nil "url" elpher-other-url) + ((special bookmarks) elpher-get-bookmarks-page nil "/" elpher-index) + ((special start) elpher-get-start-page nil)) + "Association list from types to getters, renderers, margin codes and index faces.") ;;; Customization group ;; (defgroup elpher nil - "A gopher client." + "A gopher and gemini client." :group 'applications) +;; General appearance and customizations + +(defcustom elpher-open-urls-with-eww nil + "If non-nil, open URL selectors using eww. +Otherwise, use the system browser via the BROWSE-URL function." + :type '(boolean)) + +(defcustom elpher-use-header t + "If non-nil, display current page 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)) + +(defcustom elpher-connection-timeout 5 + "Specifies the number of seconds to wait for a network connection to time out." + :type '(integer)) + +(defcustom elpher-filter-ansi-from-text nil + "If non-nil, filter ANSI escape sequences from text. +The default behaviour is to use the ansi-color package to interpret these +sequences." + :type '(boolean)) + +(defcustom elpher-certificate-directory + (file-name-as-directory (locate-user-emacs-file "elpher-certificates")) + "Specify the name of the directory where client certificates will be stored. +These certificates may be used for establishing authenticated TLS connections." + :type '(directory)) + +(defcustom elpher-openssl-command "openssl" + "The command used to launch openssl when generating TLS client certificates." + :type '(file)) + +(defcustom elpher-gemini-TLS-cert-checks nil + "If non-nil, verify gemini server TLS certs using the default security level. +Otherwise, certificate verification is disabled. + +This defaults to off because it is standard practice for Gemini servers +to use self-signed certificates, meaning that most servers provide what +EMACS considers to be an invalid certificate." + :type '(boolean)) + +(defcustom elpher-gemini-max-fill-width 80 + "Specify the maximum default width (in columns) of text/gemini documents. +The actual width used is the minimum of this value and the window width at +the time when the text is rendered." + :type '(integer)) + +(defcustom elpher-gemini-link-string "→ " + "Specify the string used to indicate links when rendering gemini maps. +May be empty." + :type '(string)) + +(defcustom elpher-gemini-bullet-string "•" + "Specify the string used for bullets when rendering gemini maps." + :type '(string)) + +(defcustom elpher-bookmarks-file (locate-user-emacs-file "elpher-bookmarks") + "Specify the name of the file where elpher bookmarks will be saved." + :type '(file)) + +(defcustom elpher-ipv4-always nil + "If non-nil, elpher will always use IPv4 to establish network connections. +This can be useful when browsing from a computer that supports IPv6, because +some servers which do not support IPv6 can take a long time to time-out." + :type '(boolean)) + ;; Face customizations +(defgroup elpher-faces nil + "Elpher face customizations." + :group 'elpher) + (defface elpher-index '((t :inherit font-lock-keyword-face)) "Face used for directory type directory records.") @@ -119,9 +220,17 @@ '((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 html type directory records.") + +(defface elpher-gemini + '((t :inherit font-lock-regexp-grouping-backslash)) + "Face used for Gemini type directory records.") + +(defface elpher-other-url '((t :inherit font-lock-comment-face)) - "Face used for url type directory records.") + "Face used for other URL type links records.") (defface elpher-telnet '((t :inherit font-lock-function-name-face)) @@ -143,125 +252,170 @@ '((t :inherit shadow)) "Face used for brackets around directory margin key.") -;; Other customizations - -(defcustom elpher-open-urls-with-eww nil - "If non-nil, open URL selectors using eww. -Otherwise, use the system browser via the BROWSE-URL function." - :type '(boolean)) - -(defcustom elpher-buttonify-urls-in-directories nil - "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)) +(defface elpher-gemini-heading1 + '((t :inherit bold :height 1.8)) + "Face used for gemini heading level 1.") -(defcustom elpher-use-header t - "If non-nil, display current node information in buffer header." - :type '(boolean)) +(defface elpher-gemini-heading2 + '((t :inherit bold :height 1.5)) + "Face used for gemini heading level 2.") -(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)) +(defface elpher-gemini-heading3 + '((t :inherit bold :height 1.2)) + "Face used for gemini heading level 3.") +(defface elpher-gemini-preformatted + '((t :inherit fixed-pitch)) + "Face used for pre-formatted gemini text blocks.") ;;; Model ;; ;; Address -(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))) +;; 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))) + (unless (and (not (url-fullness url)) (url-type url)) + (setf (url-fullness url) t) + (setf (url-filename url) + (url-unhex-string (url-filename url))) + (unless (url-type url) + (setf (url-type url) "gopher")) + (when (or (equal "gopher" (url-type url)) + (equal "gophers" (url-type url))) + ;; Gopher defaults + (unless (url-host url) + (setf (url-host url) (url-filename url)) + (setf (url-filename url) "")) + (when (or (equal (url-filename url) "") + (equal (url-filename url) "/")) + (setf (url-filename url) "/1"))) + (when (equal "gemini" (url-type url)) + ;; Gemini defaults + (if (equal (url-filename url) "") + (setf (url-filename url) "/")))) + (elpher-remove-redundant-ports url)) + (set-match-data data)))) + +(defun elpher-remove-redundant-ports (address) + "Remove redundant port specifiers from ADDRESS. +Here 'redundant' means that the specified port matches the default +for that protocol, eg 70 for gopher." + (if (and (not (elpher-address-special-p address)) + (eq (url-portspec address) ; (url-port) is too slow! + (pcase (url-type address) + ("gemini" 1965) + ((or "gopher" "gophers") 70) + ("finger" 79) + (_ -1)))) + (setf (url-portspec address) nil)) + address) + +(defun elpher-make-gopher-address (type selector host port &optional tls) + "Create an ADDRESS object using gopher directory record attributes. +The basic attributes include: TYPE, SELECTOR, HOST and PORT. +If the optional attribute TLS is non-nil, the address will be marked as +requiring gopher-over-TLS." + (cond + ((equal type ?i) nil) + ((and (equal type ?h) + (string-prefix-p "URL:" selector)) + (elpher-address-from-url (elt (split-string selector "URL:") 1))) + ((equal type ?8) + (elpher-address-from-url + (concat "telnet" + "://" host + ":" (number-to-string port)))) + (t + (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 address symbol TYPE." + type) + +(defun elpher-address-to-url (address) + "Get string representation of ADDRESS, or nil if ADDRESS is special." + (if (elpher-address-special-p address) + nil + (url-encode-url (url-recreate-url address)))) (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 type of ADDRESS object. +This is used to determine how to retrieve and render the document the +address refers to, via the table `elpher-type-map'." + (if (symbolp address) + (list 'special address) + (let ((protocol (url-type address))) + (cond ((or (equal protocol "gopher") + (equal protocol "gophers")) + (list 'gopher + (if (member (url-filename address) '("" "/")) + ?1 + (string-to-char (substring (url-filename address) 1))))) + ((equal protocol "gemini") + 'gemini) + ((equal protocol "telnet") + 'telnet) + ((equal protocol "finger") + 'finger) + (t 'other-url))))) + +(defun elpher-address-protocol (address) + "Retrieve the transport protocol for ADDRESS. This is nil for special addresses." + (if (symbolp address) + nil + (url-type address))) + +(defun elpher-address-filename (address) + "Retrieve the filename component of ADDRESS. +For gopher addresses this is a combination of the selector type and selector." + (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)) +(defun elpher-address-user (address) + "Retrieve user from ADDRESS object." + (url-user address)) -(defun elpher-address-use-tls-p (address) - "Return non-nil if ADDRESS is marked as needing TLS." - (elt address 4)) +(defun elpher-address-port (address) + "Retrieve port from ADDRESS object. +If no address is defined, returns 0. (This is for compatibility with the URL library.)" + (if (symbolp address) + 0 + (url-port address))) (defun elpher-address-special-p (address) - "Return non-nil if ADDRESS is special (e.g. start page, bookmarks page)." - (not (elpher-address-host address))) - -(defun elpher-get-address-url (address) - "Get URL representation of ADDRESS." - (let ((type (elpher-address-type address)) - (selector (elpher-address-selector address)) - (bare-host (elpher-address-host address)) - (port (elpher-address-port address))) - (url-encode-url - (let ((host (if (string-match-p ":" bare-host) - (concat "[" bare-host "]") - bare-host))) - (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)))))) - -;; Node - -(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. - -ADDRESS specifies the address of the gopher 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-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-set-node-parent (node parent) - "Set the parent node of NODE to be PARENT." - (setcar (cdr (cdr node)) parent)) + "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." + (and (not (elpher-address-special-p address)) + (member (elpher-address-protocol address) '("gopher gophers")))) + +(defun elpher-gopher-address-selector (address) + "Retrieve gopher selector from ADDRESS object." + (if (member (url-filename address) '("" "/")) + "" + (url-unhex-string (substring (url-filename address) 2)))) + ;; Cache @@ -284,52 +438,76 @@ initially." "Set the cursor position cache for ADDRESS to POS." (puthash address pos elpher-pos-cache)) -;; Node graph traversal -(defvar elpher-current-node nil) +;; Page + +(defun elpher-make-page (display-string address) + "Create a page with DISPLAY-STRING and ADDRESS." + (list display-string address)) + +(defun elpher-page-display-string (page) + "Retrieve the display string corresponding to PAGE." + (elt page 0)) + +(defun elpher-page-address (page) + "Retrieve the address corresponding to PAGE." + (elt page 1)) + +(defun elpher-page-set-address (page new-address) + "Set the address corresponding to PAGE to NEW-ADDRESS." + (setcar (cdr page) new-address)) + +(defvar elpher-current-page nil) ; buffer local +(defvar elpher-history nil) ; buffer local -(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." +(defun elpher-visit-page (page &optional renderer no-history) + "Visit PAGE using its own renderer or RENDERER, if non-nil. +Additionally, push PAGE onto the stack of previously-visited pages, +unless NO-HISTORY 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)) - (type-record (alist-get type elpher-type-map))) - (if type-record - (funcall (car type-record)) - (elpher-visit-parent-node) - (error "Unsupported gopher selector type '%c'" type))))) - -(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 nil t)))) + (unless (or no-history + (equal (elpher-page-address elpher-current-page) + (elpher-page-address page))) + (push elpher-current-page elpher-history)) + (setq-local elpher-current-page page) + (let* ((address (elpher-page-address page)) + (type (elpher-address-type address)) + (type-record (cdr (assoc type elpher-type-map)))) + (if type-record + (funcall (car type-record) + (if renderer + renderer + (cadr type-record))) + (elpher-visit-previous-page) + (pcase type + (`(gopher ,type-char) + (error "Unsupported gopher selector type '%c' for '%s'" + type-char (elpher-address-to-url address))) + (other + (error "Unsupported address type '%S' for '%s'" + other (elpher-address-to-url address))))))) + +(defun elpher-visit-previous-page () + "Visit the previous page in the history." + (let ((previous-page (pop elpher-history))) + (if previous-page + (elpher-visit-page previous-page nil t) + (error "No previous page")))) -(defun elpher-reload-current-node () - "Reload the current node, discarding any existing cached content." - (elpher-cache-content (elpher-node-address elpher-current-node) nil) - (elpher-visit-node elpher-current-node)) +(defun elpher-reload-current-page () + "Reload the current page, discarding any existing cached content." + (elpher-cache-content (elpher-page-address elpher-current-page) nil) + (elpher-visit-page elpher-current-page)) (defun elpher-save-pos () - "Save the current position of point to the current node." - (when elpher-current-node - (elpher-cache-pos (elpher-node-address elpher-current-node) (point)))) + "Save the current position of point to the current page." + (when elpher-current-page + (elpher-cache-pos (elpher-page-address elpher-current-page) (point)))) (defun elpher-restore-pos () - "Restore the position of point to that cached in the current node." - (let ((pos (elpher-get-cached-pos (elpher-node-address elpher-current-node)))) + "Restore the position of point to that cached in the current page." + (let ((pos (elpher-get-cached-pos (elpher-page-address elpher-current-page)))) (if pos (goto-char pos) (goto-char (point-min))))) @@ -338,19 +516,51 @@ unless PRESERVE-PARENT is non-nil." ;;; Buffer preparation ;; +(defvar elpher-buffer-name "*elpher*" + "The default name of the Elpher buffer.") + (defun elpher-update-header () - "If `elpher-use-header' is true, display current node info in window header." + "If `elpher-use-header' is true, display current page info in window header." (if elpher-use-header - (setq header-line-format (elpher-node-display-string elpher-current-node)))) + (let* ((display-string (elpher-page-display-string elpher-current-page)) + (address (elpher-page-address elpher-current-page)) + (tls-string (if (and (not (elpher-address-special-p address)) + (member (elpher-address-protocol address) + '("gophers" "gemini"))) + " [TLS encryption]" + "")) + (header (url-unhex-string + (concat display-string + (propertize tls-string 'face 'bold))))) + (setq header-line-format header)))) (defmacro elpher-with-clean-buffer (&rest args) "Evaluate ARGS with a clean *elpher* buffer as current." - (list 'with-current-buffer "*elpher*" - '(elpher-mode) - (append (list 'let '((inhibit-read-only t)) - '(erase-buffer) - '(elpher-update-header)) - args))) + `(with-current-buffer elpher-buffer-name + (unless (eq major-mode 'elpher-mode) + ;; avoid resetting buffer-local variables + (elpher-mode)) + (let ((inhibit-read-only t)) + (setq-local network-security-level + (default-value 'network-security-level)) + (erase-buffer) + (elpher-update-header) + ,@args))) + +(defun elpher-buffer-message (string &optional line) + "Replace first line in elpher buffer with STRING. +If LINE is non-nil, replace that line instead." + (with-current-buffer elpher-buffer-name + (let ((inhibit-read-only t)) + (goto-char (point-min)) + (if line + (forward-line line)) + (let ((data (match-data))) + (unwind-protect + (progn + (re-search-forward "^.*$") + (replace-match string)) + (set-match-data data)))))) ;;; Text Processing @@ -373,26 +583,339 @@ away CRs and any terminating period." (elpher-decode (replace-regexp-in-string "\n\.\n$" "\n" (replace-regexp-in-string "\r" "" string)))) -;;; Index rendering + +;;; Network error reporting +;; + +(defun elpher-network-error (address error) + "Display ERROR message following unsuccessful negotiation with ADDRESS. +ERROR can be either an error object or a string." + (elpher-with-clean-buffer + (insert (propertize "\n---- ERROR -----\n\n" 'face 'error) + "When attempting to retrieve " (elpher-address-to-url address) ":\n" + (if (stringp error) error (error-message-string error)) "\n" + (propertize "\n----------------\n\n" 'face 'error) + "Press 'u' to return to the previous page."))) + + +;;; General network communication ;; +(defvar elpher-network-timer nil + "Timer used for network connections.") + +(defvar elpher-use-tls nil + "If non-nil, use TLS to communicate with gopher servers.") + +(defvar elpher-client-certificate nil + "If non-nil, contains client certificate details to use for TLS connections.") + +(defun elpher-process-cleanup () + "Immediately shut down any extant elpher process and timers." + (let ((p (get-process "elpher-process"))) + (if p (delete-process p))) + (if (timerp elpher-network-timer) + (cancel-timer elpher-network-timer))) + +(defun elpher-get-host-response (address default-port query-string response-processor + &optional use-tls force-ipv4) + "Generic function for retrieving data from ADDRESS. + +When ADDRESS lacks a specific port, DEFAULT-PORT is used instead. +QUERY-STRING is a string sent to the host specified by ADDRESS to +illicet a response. This response is passed as an argument to the +function RESPONSE-PROCESSOR. + +If non-nil, USE-TLS specifies that the connection is to be made over +TLS. If set to gemini, the certificate verification will be disabled +unless `elpher-gemini-TLS-cert-checks' is non-nil. + +If non-nil, FORCE-IPV4 causes the network connection to be made over +ipv4 only. (The default behaviour when this is not set depends on +the host operating system and the local network capabilities." + (if (and use-tls (not (gnutls-available-p))) + (error "Use of TLS requires Emacs to be compiled with GNU TLS support") + (unless (< (elpher-address-port address) 65536) + (error "Cannot establish network connection: port number > 65536")) + (when (and (eq use-tls 'gemini) (not elpher-gemini-TLS-cert-checks)) + (setq-local network-security-level 'low)) + (condition-case nil + (let* ((kill-buffer-query-functions nil) + (port (elpher-address-port address)) + (host (elpher-address-host address)) + (response-string-parts nil) + (bytes-received 0) + (hkbytes-received 0) + (proc (make-network-process :name "elpher-process" + :host host + :family (and force-ipv4 'ipv4) + :service (if (> port 0) port default-port) + :buffer nil + :coding 'binary + :noquery t + :nowait t + :tls-parameters + (and use-tls + (cons 'gnutls-x509pki + (gnutls-boot-parameters + :type 'gnutls-x509pki + :hostname host + :keylist + (elpher-get-current-keylist address)))))) + (timer (run-at-time elpher-connection-timeout nil + (lambda () + (elpher-process-cleanup) + (cond + ; Try again with IPv4 + ((not force-ipv4) + (message "Connection timed out. Retrying with IPv4.") + (elpher-get-host-response address default-port + query-string + response-processor + use-tls t)) + ((and use-tls + (not (eq use-tls 'gemini)) + (or elpher-auto-disengage-TLS + (y-or-n-p + "TLS connetion failed. Disable TLS mode and retry? "))) + (setq elpher-use-tls nil) + (elpher-get-host-response address default-port + query-string + response-processor + nil force-ipv4)) + (t + (elpher-network-error address "Connection time-out."))))))) + (setq elpher-network-timer timer) + (elpher-buffer-message (concat "Connecting to " host "..." + " (press 'u' to abort)")) + (set-process-filter proc + (lambda (_proc string) + (when timer + (cancel-timer timer) + (setq timer nil)) + (setq bytes-received (+ bytes-received (length string))) + (let ((new-hkbytes-received (/ bytes-received 102400))) + (when (> new-hkbytes-received hkbytes-received) + (setq hkbytes-received new-hkbytes-received) + (elpher-buffer-message + (concat "(" + (number-to-string (/ hkbytes-received 10.0)) + " MB read)") + 1))) + (setq response-string-parts + (cons string response-string-parts)))) + (set-process-sentinel proc + (lambda (proc event) + (when timer + (cancel-timer timer)) + (condition-case the-error + (cond + ((string-prefix-p "open" event) ; request URL + (elpher-buffer-message + (concat "Connected to " host ". Receiving data..." + " (press 'u' to abort)")) + (let ((inhibit-eol-conversion t)) + (process-send-string proc query-string))) + ((string-prefix-p "deleted" event)) ; do nothing + ((and (not response-string-parts) + (not (or elpher-ipv4-always force-ipv4))) + ; Try again with IPv4 + (message "Connection failed. Retrying with IPv4.") + (elpher-get-host-response address default-port + query-string + response-processor + use-tls t)) + (response-string-parts + (elpher-with-clean-buffer + (insert "Data received. Rendering...")) + (funcall response-processor + (apply #'concat (reverse response-string-parts))) + (elpher-restore-pos)) + (t + (error "No response from server"))) + (error + (elpher-network-error address the-error)))))) + (error + (error "Error initiating connection to server"))))) + + +;;; Client-side TLS Certificate Management +;; + +(defun elpher-generate-certificate (common-name key-file cert-file &optional temporary) + "Generate a key and a self-signed client TLS certificate using openssl. + +The Common Name field of the certificate is set to COMMON-NAME. The +arguments KEY-FILE and CERT-FILE should contain the absolute paths of +the key and certificate files to write. + +If TEMPORARY is non-nil, the certificate will be given an exporation +period of one day, and the key and certificate files will be deleted +when the certificate is no longer needed for the current session. + +Otherwise, the certificate will be given a 100 year expiration period +and the files will not be deleted. + +The function returns a list containing the current host name, the +temporary flag, and the key and cert file names in the form required +by `gnutls-boot-parameters`." + (let ((exp-key-file (expand-file-name key-file)) + (exp-cert-file (expand-file-name cert-file))) + (condition-case nil + (progn + (call-process elpher-openssl-command nil nil nil + "req" "-x509" "-newkey" "rsa:2048" + "-days" (if temporary "1" "36500") + "-nodes" + "-subj" (concat "/CN=" common-name) + "-keyout" exp-key-file + "-out" exp-cert-file) + (list (elpher-address-host (elpher-page-address elpher-current-page)) + temporary exp-key-file exp-cert-file)) + (error + (message "Check that openssl is installed, or customize `elpher-openssl-command`.") + (error "Program 'openssl', required for certificate generation, not found"))))) + +(defun elpher-generate-throwaway-certificate () + "Generate and return details of a throwaway certificate. +The key and certificate files will be deleted when they are no +longer needed for this session." + (let* ((file-base (make-temp-name "elpher")) + (key-file (concat temporary-file-directory file-base ".key")) + (cert-file (concat temporary-file-directory file-base ".crt"))) + (elpher-generate-certificate file-base key-file cert-file t))) + +(defun elpher-generate-persistent-certificate (file-base common-name) + "Generate and return details of a persistent certificate. +The argument FILE-BASE is used as the base for the key and certificate +files, while COMMON-NAME specifies the common name field of the +certificate. + +The key and certificate files are written to in `elpher-certificate-directory'." + (let* ((key-file (concat elpher-certificate-directory file-base ".key")) + (cert-file (concat elpher-certificate-directory file-base ".crt"))) + (elpher-generate-certificate common-name key-file cert-file))) + +(defun elpher-get-existing-certificate (file-base) + "Return a certificate object corresponding to an existing certificate. +It is assumed that the key files FILE-BASE.key and FILE-BASE.crt exist in +the directory `elpher-certificate-directory'." + (let* ((key-file (concat elpher-certificate-directory file-base ".key")) + (cert-file (concat elpher-certificate-directory file-base ".crt"))) + (list (elpher-address-host (elpher-page-address elpher-current-page)) + nil + (expand-file-name key-file) + (expand-file-name cert-file)))) + +(defun elpher-install-and-use-existing-certificate (key-file-src cert-file-src file-base) + "Install a key+certificate file pair in `elpher-certificate-directory'. +The strings KEY-FILE-SRC and CERT-FILE-SRC are the existing key and +certificate files to install. The argument FILE-BASE is used as the +base for the installed key and certificate files." + (let* ((key-file (concat elpher-certificate-directory file-base ".key")) + (cert-file (concat elpher-certificate-directory file-base ".crt"))) + (if (or (file-exists-p key-file) + (file-exists-p cert-file)) + (error "A certificate with base name %s is already installed" file-base)) + (copy-file key-file-src key-file) + (copy-file cert-file-src cert-file) + (list (elpher-address-host (elpher-page-address elpher-current-page)) + nil + (expand-file-name key-file) + (expand-file-name cert-file)))) + +(defun elpher-list-existing-certificates () + "Return a list of the persistent certificates in `elpher-certificate-directory'." + (unless (file-directory-p elpher-certificate-directory) + (make-directory elpher-certificate-directory)) + (mapcar + (lambda (file) + (file-name-sans-extension file)) + (directory-files elpher-certificate-directory nil "\.key$"))) + +(defun elpher-forget-current-certificate () + "Causes any current certificate to be forgotten.) +In the case of throwaway certificates, the key and certificate files +are also deleted." + (interactive) + (when elpher-client-certificate + (unless (and (called-interactively-p 'any) + (not (y-or-n-p (concat "Really forget client certificate? " + "(Throwaway certificates will be deleted.)")))) + (when (cadr elpher-client-certificate) + (delete-file (elt elpher-client-certificate 2)) + (delete-file (elt elpher-client-certificate 3))) + (setq elpher-client-certificate nil) + (if (called-interactively-p 'any) + (message "Client certificate forgotten."))))) + +(defun elpher-get-current-keylist (address) + "Retrieve the `gnutls-boot-parameters'-compatable keylist. + +This is obtained from the client certificate described by +`elpher-current-certificate', if one is available and the host for +that certificate matches the host in ADDRESS. + +If `elpher-current-certificate' is non-nil, and its host name doesn't +match that of ADDRESS, the certificate is forgotten." + (if elpher-client-certificate + (if (string= (car elpher-client-certificate) + (elpher-address-host address)) + (list (cddr elpher-client-certificate)) + (elpher-forget-current-certificate) + (message "Disabling client certificate for new host") + nil) + nil)) + + +;;; Gopher selector retrieval +;; + +(defun elpher-get-gopher-response (address renderer) + "Get response string from gopher server at ADDRESS and render using RENDERER." + (elpher-get-host-response address 70 + (concat (elpher-gopher-address-selector address) "\r\n") + renderer + (or (string= (elpher-address-protocol address) "gophers") + elpher-use-tls))) + +(defun elpher-get-gopher-page (renderer) + "Getter function for gopher pages. +The RENDERER procedure is used to display the contents of the page +once they are retrieved from the gopher server." + (let* ((address (elpher-page-address elpher-current-page)) + (content (elpher-get-cached-content address))) + (if (and content (funcall renderer nil)) + (elpher-with-clean-buffer + (insert content) + (elpher-restore-pos)) + (elpher-with-clean-buffer + (insert "LOADING... (use 'u' to cancel)\n")) + (condition-case the-error + (elpher-get-gopher-response address renderer) + (error + (elpher-network-error address the-error)))))) + +;; Index rendering + (defun elpher-insert-index (string) "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-processed (elpher-preprocess-text-response string))) (dolist (line (split-string str-processed "\n")) - (unless (= (length line) 0) - (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)))))) + (ignore-errors + (unless (= (length line) 0) + (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-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." @@ -406,386 +929,595 @@ away CRs and any terminating period." (insert " ")) (insert (make-string elpher-margin-width ?\s)))) -(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 address) +(defun elpher--page-button-help (_window buffer pos) + "Function called by Emacs to generate mouse-over text. +The arguments specify the BUFFER and the POS within the buffer of the item +for which help is required. The function returns the help to be +displayed. The _WINDOW argument is currently unused." + (with-current-buffer buffer + (let ((button (button-at pos))) + (when button + (let* ((page (button-get button 'elpher-page)) + (address (elpher-page-address page))) + (format "mouse-1, RET: open '%s'" (if (elpher-address-special-p address) + address + (elpher-address-to-url address)))))))) + +(defun elpher-insert-index-record (display-string &optional 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))) +The contents of the record are dictated by DISPLAY-STRING and ADDRESS. +If ADDRESS is not supplied or nil the record is rendered as an +'information' line." + (let* ((type (if address (elpher-address-type address) nil)) + (type-map-entry (cdr (assoc type elpher-type-map)))) (if type-map-entry - (let* ((margin-code (elt type-map-entry 1)) - (face (elt type-map-entry 2)) - (node (elpher-make-node display-string address))) + (let* ((margin-code (elt type-map-entry 2)) + (face (elt type-map-entry 3)) + (filtered-display-string (elpher-color-filter-apply display-string)) + (page (elpher-make-page filtered-display-string address))) (elpher-insert-margin margin-code) - (insert-text-button display-string + (insert-text-button filtered-display-string 'face face - 'elpher-node node + 'elpher-page page 'action #'elpher-click-link 'follow-link t - 'help-echo (elpher-node-button-help node))) + 'help-echo #'elpher--page-button-help)) (pcase type - (?i ;; Information + ('nil ;; 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) "?")) + (let ((propertized-display-string + (propertize display-string 'face 'elpher-info))) + (insert (elpher-process-text-for-display propertized-display-string)))) + (`(gopher ,selector-type) ;; Unknown + (elpher-insert-margin (concat (char-to-string selector-type) "?")) (insert (propertize display-string 'face 'elpher-unknown))))) (insert "\n"))) (defun elpher-click-link (button) "Function called when the gopher link BUTTON is activated (via mouse or keypress)." - (let ((node (button-get button 'elpher-node))) - (elpher-visit-node node))) - - -;;; Selector retrieval (all kinds) -;; - -(defun elpher-process-cleanup () - "Immediately shut down any extant elpher process." - (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.") + (let ((page (button-get button 'elpher-page))) + (elpher-visit-page page))) -(defvar elpher-selector-string) - -(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’. - -Usually errors result in an error page being displayed. This is only -appropriate if the selector is to be directly viewed. If PROPAGATE-ERROR -is non-nil, this message is not displayed. Instead, the error propagates -up to the calling function." - (setq elpher-selector-string "") - (when (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-render-index (data &optional _mime-type-string) + "Render DATA as an index. MIME-TYPE-STRING is unused." + (elpher-with-clean-buffer + (if (not data) + t + (elpher-insert-index data) + (elpher-cache-content (elpher-page-address elpher-current-page) + (buffer-string))))) -(defun elpher-get-index-node () - "Getter which retrieves the current node contents as an index." - (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))) - (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 +;; Text rendering (defconst elpher-url-regex - "\\([a-zA-Z]+\\)://\\([a-zA-Z0-9.\-]+\\|\[[a-zA-Z0-9:]+\]\\)\\(?3::[0-9]+\\)?\\(?4:/[^ \r\n\t(),]*\\)?" + "\\([a-zA-Z]+\\)://\\([a-zA-Z0-9.\-]*[a-zA-Z0-9\-]\\|\[[a-zA-Z0-9:]+\]\\)\\(:[0-9]+\\)?\\(/\\([0-9a-zA-Z\-_~?/@|:.%#=&]*[0-9a-zA-Z\-_~?/@|#]\\)?\\)?" "Regexp used to locate and buttinofy URLs in text files loaded by elpher.") -(defun elpher-make-node-from-matched-url (&optional string) - "Convert most recent `elpher-url-regex' match to a 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 (or (string= protocol "gopher") - (string= protocol "gophers")) - (let* ((bare-host (match-string 2 string)) - (host (if (string-prefix-p "[" bare-host) - (substring bare-host 1 (- (length bare-host) 1)) - bare-host)) - (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 (decode-coding-string - (url-unhex-string - (if (> (length type-and-selector) 1) - (substring type-and-selector 2) - "")) 'utf-8)) - (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 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))) + (let ((page (elpher-make-page (substring-no-properties (match-string 0)) + (elpher-address-from-url (match-string 0))))) (make-text-button (match-beginning 0) (match-end 0) - 'elpher-node node + 'elpher-page page 'action #'elpher-click-link 'follow-link t - 'help-echo (elpher-node-button-help node)))) + 'help-echo #'elpher--page-button-help + 'face 'button))) (buffer-string))) -(defun elpher-get-text-node () - "Getter which retrieves the current node contents as a text document." - (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))) - (progn - (elpher-with-clean-buffer - (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-buttonify-urls - (elpher-preprocess-text-response - elpher-selector-string))) - (elpher-restore-pos) - (elpher-cache-content - (elpher-node-address elpher-current-node) - (buffer-string)))))))))) +(defconst elpher-ansi-regex "\x1b\\[[^m]*m" + "Wildly incomplete regexp used to strip out some troublesome ANSI escape sequences.") + +(defun elpher-process-text-for-display (string) + "Perform any desired processing of STRING prior to display as text. +Currently includes buttonifying URLs and processing ANSI escape codes." + (elpher-buttonify-urls (if elpher-filter-ansi-from-text + (elpher-color-filter-apply string) + (elpher-color-apply string)))) + +(defun elpher-render-text (data &optional _mime-type-string) + "Render DATA as text. MIME-TYPE-STRING is unused." + (elpher-with-clean-buffer + (if (not data) + t + (insert (elpher-process-text-for-display (elpher-preprocess-text-response data))) + (elpher-cache-content + (elpher-page-address elpher-current-page) + (buffer-string))))) ;; Image retrieval -(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 +(defun elpher-render-image (data &optional _mime-type-string) + "Display DATA as image. MIME-TYPE-STRING is unused." + (if (not data) + nil + (if (display-images-p) (progn - (elpher-with-clean-buffer - (insert-image content) - (elpher-restore-pos))) - (if (display-images-p) - (progn + (let ((image (create-image + data + nil t))) (elpher-with-clean-buffer - (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)) - (if elpher-cache-images - (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* ((address (elpher-node-address elpher-current-node)) - (content (elpher-get-cached-content address)) - (aborted t)) - (if content - (progn - (elpher-with-clean-buffer - (insert content) - (elpher-restore-pos)) - (message "Displaying cached search results. Reload to perform a new search.")) + (insert-image image) + (elpher-restore-pos)))) + (elpher-render-download data)))) + +;; Search retrieval and rendering + +(defun elpher-get-gopher-query-page (renderer) + "Getter for gopher addresses requiring input. +The response is rendered using the rendering function RENDERER." + (let* ((address (elpher-page-address elpher-current-page)) + (content (elpher-get-cached-content address)) + (aborted t)) + (if (and content (funcall renderer nil)) + (elpher-with-clean-buffer + (insert content) + (elpher-restore-pos) + (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 - (elpher-address-host address) - (elpher-address-port address)))) + (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) + (equal (elpher-address-type address) "gophers")))) (setq aborted nil) + (elpher-with-clean-buffer (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-cache-content - (elpher-node-address elpher-current-node) - (buffer-string)))))) + (elpher-get-gopher-response search-address renderer)) (if aborted - (elpher-visit-parent-node)))))) - -;; Raw server response retrieval + (elpher-visit-previous-page)))))) + +;; Raw server response rendering -(defun elpher-get-node-raw () - "Getter which retrieves the raw server response for the current node." - (let ((address (elpher-node-address elpher-current-node))) +(defun elpher-render-raw (data &optional mime-type-string) + "Display raw DATA in buffer. MIME-TYPE-STRING is also displayed if provided." + (if (not data) + nil (elpher-with-clean-buffer - (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 - -(defvar elpher-download-filename) - -(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))) - (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: " - nil nil nil - (if (> (length filename-proposal) 0) - filename-proposal - "gopher.file")))) - (message "Downloading...") - (setq elpher-download-filename filename) + (when mime-type-string + (insert "MIME type specified by server: '" mime-type-string "'\n")) + (insert data) + (goto-char (point-min))) + (message "Displaying raw server response. Reload or redraw to return to standard view."))) + +;; File save "rendering" + +(defun elpher-render-download (data &optional _mime-type-string) + "Save DATA to file. MIME-TYPE-STRING is unused." + (if (not data) + nil + (let* ((address (elpher-page-address elpher-current-page)) + (selector (if (elpher-address-gopher-p address) + (elpher-gopher-address-selector address) + (elpher-address-filename address)))) + (elpher-visit-previous-page) ; Do first in case of non-local exits. + (let* ((filename-proposal (file-name-nondirectory selector)) + (filename (read-file-name "Download complete. Save file as: " + nil nil nil + (if (> (length filename-proposal) 0) + filename-proposal + "download.file")))) + (let ((coding-system-for-write 'binary)) + (with-temp-file filename + (insert data))) + (message (format "Saved to file %s." filename)))))) + +;; HTML rendering + +(defun elpher-render-html (data &optional _mime-type-string) + "Render DATA as HTML using shr. MIME-TYPE-STRING is unused." + (elpher-with-clean-buffer + (if (not data) + t + (let ((dom (with-temp-buffer + (insert data) + (libxml-parse-html-region (point-min) (point-max))))) + (shr-insert-document dom))))) + +;; Gemini page retrieval + +(defvar elpher-gemini-redirect-chain) + +(defun elpher-get-gemini-response (address renderer) + "Get response string from gemini server at ADDRESS and render using RENDERER." + (elpher-get-host-response address 1965 + (concat (elpher-address-to-url address) "\r\n") + (lambda (response-string) + (elpher-process-gemini-response response-string renderer)) + 'gemini)) + +(defun elpher-parse-gemini-response (response) + "Parse the RESPONSE string and return a list of components. +The list is of the form (code meta body). A response of nil implies +that the response was malformed." + (let ((header-end-idx (string-match "\r\n" response))) + (if header-end-idx + (let ((header (string-trim (substring response 0 header-end-idx))) + (body (substring response (+ header-end-idx 2)))) + (if (>= (length header) 2) + (let ((code (substring header 0 2)) + (meta (string-trim (substring header 2)))) + (list code meta body)) + (error "Malformed response: No response status found in header %s" header))) + (error "Malformed response: No CRLF-delimited header found in response %s" response)))) + +(defun elpher-process-gemini-response (response-string renderer) + "Process the gemini response RESPONSE-STRING and pass the result to RENDERER." + (let ((response-components (elpher-parse-gemini-response response-string))) + (let ((response-code (elt response-components 0)) + (response-meta (elt response-components 1)) + (response-body (elt response-components 2))) + (pcase (elt response-code 0) + (?1 ; Input required + (elpher-with-clean-buffer + (insert "Gemini server is requesting input.")) + (let* ((query-string + (if (eq (elt response-code 1) ?1) + (read-passwd (concat response-meta ": ")) + (read-string (concat response-meta ": ")))) + (query-address (seq-copy (elpher-page-address elpher-current-page))) + (old-fname (url-filename query-address))) + (setf (url-filename query-address) + (concat old-fname "?" (url-build-query-string `((,query-string))))) + (elpher-get-gemini-response query-address renderer))) + (?2 ; Normal response + (funcall renderer response-body response-meta)) + (?3 ; Redirect + (message "Following redirect to %s" response-meta) + (if (>= (length elpher-gemini-redirect-chain) 5) + (error "More than 5 consecutive redirects followed")) + (let ((redirect-address (elpher-address-from-gemini-url response-meta))) + (if (member redirect-address elpher-gemini-redirect-chain) + (error "Redirect loop detected")) + (if (not (string= (elpher-address-protocol redirect-address) + "gemini")) + (error "Server tried to automatically redirect to non-gemini URL: %s" + response-meta)) + (elpher-page-set-address elpher-current-page redirect-address) + (add-to-list 'elpher-gemini-redirect-chain redirect-address) + (elpher-get-gemini-response redirect-address renderer))) + (?4 ; Temporary failure + (error "Gemini server reports TEMPORARY FAILURE for this request: %s %s" + response-code response-meta)) + (?5 ; Permanent failure + (error "Gemini server reports PERMANENT FAILURE for this request: %s %s" + response-code response-meta)) + (?6 ; Client certificate required + (elpher-with-clean-buffer + (if elpher-client-certificate + (insert "Gemini server does not recognise the provided TLS certificate:\n\n") + (insert "Gemini server is requesting a valid TLS certificate:\n\n")) + (auto-fill-mode 1) + (elpher-gemini-insert-text response-meta)) + (let ((chosen-certificate (elpher-choose-client-certificate))) + (unless chosen-certificate + (error "Gemini server requires a client certificate and none was provided")) + (setq elpher-client-certificate chosen-certificate)) + (elpher-with-clean-buffer) + (elpher-get-gemini-response (elpher-page-address elpher-current-page) renderer)) + (_other + (error "Gemini server response unknown: %s %s" + response-code response-meta)))))) + +(defun elpher-choose-client-certificate () + "Prompt for a client certificate to use to establish a TLS connection." + (let* ((read-answer-short t)) + (pcase (read-answer "What do you want to do? " + '(("throwaway" ?t + "generate and use throw-away certificate") + ("persistent" ?p + "generate new or use existing persistent certificate") + ("abort" ?a + "stop immediately"))) + ("throwaway" + (setq elpher-client-certificate (elpher-generate-throwaway-certificate))) + ("persistent" + (let* ((existing-certificates (elpher-list-existing-certificates)) + (file-base (completing-read + "Nickname for new or existing certificate (autocompletes, empty response aborts): " + existing-certificates))) + (if (string-empty-p (string-trim file-base)) + nil + (if (member file-base existing-certificates) + (setq elpher-client-certificate + (elpher-get-existing-certificate file-base)) + (pcase (read-answer "Generate new certificate or install externally-generated one? " + '(("new" ?n + "generate new certificate") + ("install" ?i + "install existing certificate") + ("abort" ?a + "stop immediately"))) + ("new" + (let ((common-name (read-string "Common Name field for new certificate: " + file-base))) + (message "New key and self-signed certificate written to %s" + elpher-certificate-directory) + (elpher-generate-persistent-certificate file-base common-name))) + ("install" + (let* ((cert-file (read-file-name "Certificate file: " nil nil t)) + (key-file (read-file-name "Key file: " nil nil t))) + (message "Key and certificate installed in %s for future use" + elpher-certificate-directory) + (elpher-install-and-use-existing-certificate key-file + cert-file + file-base))) + ("abort" nil)))))) + ("abort" nil)))) + +(defun elpher-get-gemini-page (renderer) + "Getter which retrieves and renders a Gemini page and renders it using RENDERER." + (let* ((address (elpher-page-address elpher-current-page)) + (content (elpher-get-cached-content address))) + (condition-case the-error + (if (and content (funcall renderer nil)) + (elpher-with-clean-buffer + (insert content) + (elpher-restore-pos)) + (elpher-with-clean-buffer + (insert "LOADING GEMINI... (use 'u' to cancel)\n")) + (setq elpher-gemini-redirect-chain nil) + (elpher-get-gemini-response address renderer)) + (error + (elpher-network-error address the-error))))) + +(defun elpher-render-gemini (body &optional mime-type-string) + "Render gemini response BODY with rendering MIME-TYPE-STRING." + (if (not body) + t + (let* ((mime-type-string* (if (or (not mime-type-string) + (string-empty-p mime-type-string)) + "text/gemini; charset=utf-8" + mime-type-string)) + (mime-type-split (split-string mime-type-string* ";" t)) + (mime-type (string-trim (car mime-type-split))) + (parameters (mapcar (lambda (s) + (let ((key-val (split-string s "="))) + (list (downcase (string-trim (car key-val))) + (downcase (string-trim (cadr key-val)))))) + (cdr mime-type-split)))) + (when (string-prefix-p "text/" mime-type) + (setq body (decode-coding-string + body + (if (assoc "charset" parameters) + (intern (cadr (assoc "charset" parameters))) + 'utf-8))) + (setq body (replace-regexp-in-string "\r" "" body))) + (pcase mime-type + ((or "text/gemini" "") + (elpher-render-gemini-map body parameters)) + ("text/html" + (elpher-render-html body)) + ((pred (string-prefix-p "text/")) + (elpher-render-gemini-plain-text body parameters)) + ((pred (string-prefix-p "image/")) + (elpher-render-image body)) + (_other + (elpher-render-download body)))))) + +(defun elpher-gemini-get-link-url (link-line) + "Extract the url portion of LINK-LINE, a gemini map file link line. +Returns nil in the event that the contents of the line following the +=> prefix are empty." + (let ((l (split-string (substring link-line 2)))) + (if l + (string-trim (elt l 0)) + nil))) + +(defun elpher-gemini-get-link-display-string (link-line) + "Extract the display string portion of LINK-LINE, a gemini map file link line. +Returns the url portion in the event that the display-string portion is empty." + (let* ((rest (string-trim (elt (split-string link-line "=>") 1))) + (idx (string-match "[ \t]" rest))) + (string-trim (if idx + (substring rest (+ idx 1)) + rest)))) + +(defun elpher-collapse-dot-sequences (filename) + "Collapse dot sequences in FILENAME. +For instance, the filename /a/b/../c/./d will reduce to /a/c/d" + (let* ((path (split-string filename "/")) + (path-reversed-normalized + (seq-reduce (lambda (a b) + (cond ((and a (equal b "..") (cdr a))) + ((and (not a) (equal b "..")) a) ;leading .. are dropped + ((equal b ".") a) + (t (cons b a)))) + path nil))) + (string-join (reverse path-reversed-normalized) "/"))) + +(defun elpher-address-from-gemini-url (url) + "Extract address from URL with defaults as per gemini map files. +While there's obviously some redundancy here between this function and +`elpher-address-from-url', gemini map file URLs require enough special +treatment that a separate function is warranted." + (let ((address (url-generic-parse-url url)) + (current-address (elpher-page-address elpher-current-page))) + (unless (and (url-type address) (not (url-fullness address))) ;avoid mangling mailto: urls + (setf (url-fullness address) t) + (if (url-host address) ;if there is an explicit host, filenames are absolute + (if (string-empty-p (url-filename address)) + (setf (url-filename address) "/")) ;ensure empty filename is marked as absolute + (setf (url-host address) (url-host current-address)) + (setf (url-port address) (url-port current-address)) + (unless (string-prefix-p "/" (url-filename address)) ;deal with relative links + (setf (url-filename address) + (concat (file-name-directory (url-filename current-address)) + (url-filename address))))) + (unless (url-type address) + (setf (url-type address) "gemini")) + (when (equal (url-type address) "gemini") + (setf (url-filename address) + (elpher-collapse-dot-sequences (url-filename address))))) + (elpher-remove-redundant-ports address))) + +(defun elpher-gemini-insert-link (link-line) + "Insert link described by LINK-LINE into a text/gemini document." + (let* ((url (elpher-gemini-get-link-url link-line)) + (display-string (elpher-gemini-get-link-display-string link-line)) + (address (elpher-address-from-gemini-url url)) + (type (if address (elpher-address-type address) nil)) + (type-map-entry (cdr (assoc type elpher-type-map)))) + (when display-string + (insert elpher-gemini-link-string) + (if type-map-entry + (let* ((face (elt type-map-entry 3)) + (filtered-display-string (elpher-color-filter-apply display-string)) + (page (elpher-make-page filtered-display-string address))) + (insert-text-button filtered-display-string + 'face face + 'elpher-page page + 'action #'elpher-click-link + 'follow-link t + 'help-echo #'elpher--page-button-help)) + (insert (propertize display-string 'face 'elpher-unknown))) + (insert "\n")))) + +(defun elpher-gemini-insert-header (header-line) + "Insert header described by HEADER-LINE into a text/gemini document. +The gemini map file line describing the header is given +by HEADER-LINE." + (when (string-match "^\\(#+\\)[ \t]*" header-line) + (let* ((level (length (match-string 1 header-line))) + (header (substring header-line (match-end 0))) + (face (pcase level + (1 'elpher-gemini-heading1) + (2 'elpher-gemini-heading2) + (3 'elpher-gemini-heading3) + (_ 'default))) + (fill-column (/ (* fill-column + (font-get (font-spec :name (face-font 'default)) :size)) + (font-get (font-spec :name (face-font face)) :size)))) + (unless (display-graphic-p) + (insert (make-string level ?#) " ")) + (insert (propertize header 'face face)) + (newline)))) + +(defun elpher-gemini-insert-text (text-line) + "Insert a plain non-preformatted TEXT-LINE into a text/gemini document. +This function uses Emacs' auto-fill to wrap text sensibly to a maximum +width defined by elpher-gemini-max-fill-width." + (string-match "\\(^[ \t]*\\)\\(\*[ \t]+\\|>[ \t]*\\)?" text-line) + (let* ((processed-text-line (if (match-string 2 text-line) + (concat + (replace-regexp-in-string "\*" + elpher-gemini-bullet-string + (match-string 0 text-line)) + (substring text-line (match-end 0))) + text-line)) + (adaptive-fill-mode nil) + (fill-prefix (if (match-string 2 text-line) + (replace-regexp-in-string "[>\*]" " " (match-string 0 text-line)) + nil))) + (insert (elpher-process-text-for-display processed-text-line)) + (newline))) + +(defun elpher-render-gemini-map (data _parameters) + "Render DATA as a gemini map file, PARAMETERS is currently unused." + (elpher-with-clean-buffer + (let ((preformatted nil)) + (auto-fill-mode 1) + (setq-local fill-column (min (window-width) elpher-gemini-max-fill-width)) + (dolist (line (split-string data "\n")) + (cond + ((string-prefix-p "```" line) (setq preformatted (not preformatted))) + (preformatted (insert (elpher-process-text-for-display + (propertize line 'face 'elpher-gemini-preformatted)) + "\n")) + ((string-prefix-p "=>" line) (elpher-gemini-insert-link line)) + ((string-prefix-p "#" line) (elpher-gemini-insert-header line)) + (t (elpher-gemini-insert-text line))))) + (elpher-cache-content + (elpher-page-address elpher-current-page) + (buffer-string)))) + +(defun elpher-render-gemini-plain-text (data _parameters) + "Render DATA as plain text file. PARAMETERS is currently unused." + (elpher-with-clean-buffer + (insert (elpher-process-text-for-display data)) + (elpher-cache-content + (elpher-page-address elpher-current-page) + (buffer-string)))) + + +;; Finger page connection + +(defun elpher-get-finger-page (renderer) + "Opens a finger connection to the current page address. +The result is rendered using RENDERER." + (let* ((address (elpher-page-address elpher-current-page)) + (content (elpher-get-cached-content address))) + (if (and content (funcall renderer nil)) + (elpher-with-clean-buffer + (insert content) + (elpher-restore-pos)) + (elpher-with-clean-buffer + (insert "LOADING... (use 'u' to cancel)\n")) (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) + (let* ((kill-buffer-query-functions nil) + (user (let ((filename (elpher-address-filename address))) + (if (> (length filename) 1) + (substring filename 1) + (elpher-address-user address))))) + (elpher-get-host-response address 79 + (concat user "\r\n") + renderer)) (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))) - (let ((url (elt (split-string selector "URL:") 1))) - (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 - -(defun elpher-get-telnet-node () - "Getter which opens a telnet connection to the server specified by the current node." - (let* ((address (elpher-node-address elpher-current-node)) - (host (elpher-address-host address)) - (port (elpher-address-port address))) - (elpher-visit-parent-node) - (telnet host port))) + (elpher-network-error address the-error)))))) -;; Start page node retrieval -(defun elpher-get-start-node () - "Getter which displays the start page." +;; Telnet page connection + +(defun elpher-get-telnet-page (renderer) + "Opens a telnet connection to the current page address (RENDERER must be nil)." + (when renderer + (elpher-visit-previous-page) + (error "Command not supported for telnet URLs")) + (let* ((address (elpher-page-address elpher-current-page)) + (host (elpher-address-host address)) + (port (elpher-address-port address))) + (elpher-visit-previous-page) + (if (> port 0) + (telnet host port) + (telnet host)))) + + +;; Other URL page opening + +(defun elpher-get-other-url-page (renderer) + "Getter which attempts to open the URL specified by the current page (RENDERER must be nil)." + (when renderer + (elpher-visit-previous-page) + (error "Command not supported for general URLs")) + (let* ((address (elpher-page-address elpher-current-page)) + (url (elpher-address-to-url address))) + (progn + (elpher-visit-previous-page) ; Do first in case of non-local exits. + (message "Opening URL...") + (if elpher-open-urls-with-eww + (browse-web url) + (browse-url url))))) + + +;; Start page page retrieval + +(defun elpher-get-start-page (renderer) + "Getter which displays the start page (RENDERER must be nil)." + (when renderer + (elpher-visit-previous-page) + (error "Command not supported for start page")) (elpher-with-clean-buffer (insert " --------------------------------------------\n" - " Elpher Gopher Client \n" + " Elpher Gopher and Gemini Client \n" " version " elpher-version "\n" " --------------------------------------------\n" "\n" @@ -794,9 +1526,10 @@ calls, as is necessary if the match is performed by `string-match'." " - 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" + " - u/mouse-3/U: return to previous page or to the start page\n" " - o/O: visit different selector or the root menu of the current server\n" - " - g: go to a particular gopher address\n" + " - g: go to a particular address (gopher, gemini, finger)\n" + " - d/D: download item under cursor or current page\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" @@ -804,24 +1537,38 @@ calls, as is necessary if the match is performed by `string-match'." " - 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" - " - w: display the raw server response for the current page\n" - " - S: set an explicit character coding system (default is to autodetect)\n" + " - S: set character coding system for gopher (default is to autodetect)\n" + " - T: toggle TLS gopher mode\n" + " - F: forget/discard current TLS client certificate\n" + " - .: display the raw server response for the current page\n" "\n" - "Start your exploration of gopher space:\n") + "Start your exploration of gopher space and gemini:\n") (elpher-insert-index-record "Floodgap Systems Gopher Server" - (elpher-make-address ?1 "" "gopher.floodgap.com" 70)) + (elpher-make-gopher-address ?1 "" "gopher.floodgap.com" 70)) + (elpher-insert-index-record "Project Gemini home page" + (elpher-address-from-url "gemini://gemini.circumlunar.space/")) + (insert "\n" + "Alternatively, select a search engine and enter some search terms:\n") + (elpher-insert-index-record "Gopher Search Engine (Veronica-2)" + (elpher-make-gopher-address ?7 "/v2/vs" "gopher.floodgap.com" 70)) + (elpher-insert-index-record "Gemini Search Engine (GUS)" + (elpher-address-from-url "gemini://gus.guru/search")) (insert "\n" - "Alternatively, select the following item and enter some search terms:\n") - (elpher-insert-index-record "Veronica-2 Gopher Search Engine" - (elpher-make-address ?7 "/v2/vs" "gopher.floodgap.com" 70)) + "This page contains your bookmarked sites (also visit with B):\n") + (elpher-insert-index-record "Your Bookmarks" 'bookmarks) + (insert "\n" + "For Elpher release news or to leave feedback, visit:\n") + (elpher-insert-index-record "The Elpher Project Page" + (elpher-make-gopher-address ?1 + "/projects/elpher/" + "thelambdalab.xyz" + 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) + 'action (lambda (_) (interactive) (info "(elpher)")) 'follow-link t @@ -829,40 +1576,54 @@ calls, as is necessary if the match is performed by `string-match'." (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.)") + " MELPA. Otherwise you will have to install the manual yourself.)\n") 'face 'shadow)) (elpher-restore-pos))) -;; Bookmarks page node retrieval +;; Bookmarks page page retrieval -(defun elpher-get-bookmarks-node () - "Getter to load and display the current bookmark list." +(defun elpher-get-bookmarks-page (renderer) + "Getter to load and display the current bookmark list (RENDERER must be nil)." + (when renderer + (elpher-visit-previous-page) + (error "Command not supported for bookmarks page")) (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))) + (address (elpher-address-from-url (elpher-bookmark-url bookmark)))) (elpher-insert-index-record display-string address))) (insert "No bookmarks found.\n"))) - (insert "\n-----------------------\n\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")) + "- a: rename selected bookmark\n" + "\n" + "Bookmarks are stored in the file ") + (let ((filename elpher-bookmarks-file) + (help-string "RET,mouse-1: Open bookmarks file in new buffer for editing.")) + (insert-text-button filename + 'face 'link + 'action (lambda (_) + (interactive) + (find-file filename)) + 'follow-link t + 'help-echo help-string)) + (insert "\n") (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)) +bookmark list, while URL is the url of the entry." + (list display-string url)) (defun elpher-bookmark-display-string (bookmark) "Get the display string of BOOKMARK." @@ -872,46 +1633,57 @@ 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 elpher-bookmarks-file (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") + (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")) - (goto-char (point-min)) - (read (current-buffer))))) + (let ((bookmarks + (with-temp-buffer + (ignore-errors + (insert-file-contents elpher-bookmarks-file) + (goto-char (point-min)) + (read (current-buffer)))))) + (if (and bookmarks (listp (cadar bookmarks))) + (progn + (message "Reading old bookmark file. (Will be updated on write.)") + (mapcar (lambda (old-bm) + (list (car old-bm) + (elpher-address-to-url (apply #'elpher-make-gopher-address + (cadr old-bm))))) + bookmarks)) + bookmarks))) (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)))) + (push (elpher-make-bookmark display-string url) bookmarks))) (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 ;; @@ -931,110 +1703,100 @@ If ADDRESS is already bookmarked, update the label only." (interactive) (push-button)) -(defun elpher-go () - "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 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-make-address ?1 selector host-or-url - (string-to-number port-string)))))))) - (switch-to-buffer "*elpher*") - (elpher-visit-node node))) +(defun elpher-go (host-or-url) + "Go to a particular gopher site HOST-OR-URL. +When run interactively HOST-OR-URL is read from the minibuffer." + (interactive "sGopher or Gemini URL: ") + (let* ((cleaned-host-or-url (string-trim host-or-url)) + (address (elpher-address-from-url cleaned-host-or-url)) + (page (elpher-make-page cleaned-host-or-url address))) + (switch-to-buffer elpher-buffer-name) + (elpher-visit-page page) + nil)) (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))) + (let ((address (elpher-page-address elpher-current-page))) (if (elpher-address-special-p address) - (error "Command not valid for this page") - (let ((url (read-string "URL: " (elpher-get-address-url address)))) - (if (string-match elpher-url-regex url) - (let ((new-node (elpher-make-node-from-matched-url url))) - (unless (equal (elpher-node-address new-node) address) - (elpher-visit-node new-node))) - (error "Could not parse URL %s" url)))))) + (error "Command invalid for this page") + (let ((url (read-string "Gopher or Gemini URL: " (elpher-address-to-url address)))) + (elpher-visit-page (elpher-make-page 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."))) + (elpher-visit-page elpher-current-page)) (defun elpher-reload () "Reload current page." (interactive) - (if elpher-current-node - (elpher-reload-current-node) - (message "No current site."))) + (elpher-reload-current-page)) (defun elpher-toggle-tls () - "Toggle TLS encryption mode." + "Toggle TLS encryption mode for gopher." (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.)") + (message "TLS gopher 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.)"))) + (error "Cannot enable TLS gopher mode: GnuTLS not available")) + (message "TLS gopher mode disabled. (Will not affect current page until reload.)"))) (defun elpher-view-raw () "View raw server response for current page." (interactive) - (if elpher-current-node - (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."))) + (if (elpher-address-special-p (elpher-page-address elpher-current-page)) + (error "This page was not generated by a server") + (elpher-visit-page elpher-current-page + #'elpher-render-raw))) (defun elpher-back () "Go to previous site." (interactive) - (if (elpher-node-parent elpher-current-node) - (elpher-visit-parent-node) - (error "No previous site"))) + (elpher-visit-previous-page)) + +(defun elpher-back-to-start () + "Go all the way back to the start page." + (interactive) + (setq-local elpher-current-page nil) + (setq-local elpher-history nil) + (let ((start-page (elpher-make-page "Elpher Start Page" + (elpher-make-special-address 'start)))) + (elpher-visit-page start-page))) (defun elpher-download () "Download the link at point." (interactive) (let ((button (button-at (point)))) (if button - (let ((node (button-get button 'elpher-node))) - (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))) + (let ((page (button-get button 'elpher-page))) + (if (elpher-address-special-p (elpher-page-address page)) + (error "Cannot download %s" + (elpher-page-display-string page)) + (elpher-visit-page (button-get button 'elpher-page) + #'elpher-render-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 + (if (elpher-address-special-p (elpher-page-address elpher-current-page)) + (error "Cannot download %s" + (elpher-page-display-string elpher-current-page)) + (elpher-visit-page (elpher-make-page + (elpher-page-display-string elpher-current-page) + (elpher-page-address elpher-current-page)) + #'elpher-render-download t))) (defun elpher-build-link-map () - "Build alist mapping link names to destination nodes in current buffer." + "Build alist mapping link names to destination pages in current buffer." (let ((link-map nil) (b (next-button (point-min) t))) (while b - (add-to-list 'link-map (cons (button-label b) b)) + (push (cons (button-label b) b) link-map) (setq b (next-button (button-start b)))) link-map)) @@ -1054,36 +1816,33 @@ host, selector and port." (defun elpher-root-dir () "Visit root of current server." (interactive) - (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))) - (if (> (length selector) 0) - (let ((root-address (elpher-make-address ?1 "" host port))) - (elpher-visit-node - (elpher-make-node (concat "gopher://" host - ":" (number-to-string port) - "/1/") - root-address))) - (error "Already at root directory of current server"))) - (error "Command invalid for this page")))) + (let ((address (elpher-page-address elpher-current-page))) + (if (not (elpher-address-special-p address)) + (if (or (member (url-filename address) '("/" "")) + (and (elpher-address-gopher-p address) + (= (length (elpher-gopher-address-selector address)) 0))) + (error "Already at root directory of current server") + (let ((address-copy (elpher-address-from-url + (elpher-address-to-url address)))) + (setf (url-filename address-copy) "") + (elpher-go (elpher-address-to-url address-copy)))) + (error "Command invalid for %s" (elpher-page-display-string elpher-current-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)) + "Return non-nil if current page is a bookmarks page." + (equal (elpher-address-type (elpher-page-address elpher-current-page)) + '(special bookmarks))) (defun elpher-reload-bookmarks () - "Reload bookmarks if current node is a bookmarks page." + "Reload bookmarks if current page is a bookmarks page." (if (elpher-bookmarks-current-p) - (elpher-reload-current-node))) + (elpher-reload-current-page))) (defun elpher-bookmark-current () - "Bookmark the current node." + "Bookmark the current page." (interactive) - (let ((address (elpher-node-address elpher-current-node)) - (display-string (elpher-node-display-string elpher-current-node))) + (let ((address (elpher-page-address elpher-current-page)) + (display-string (elpher-page-display-string elpher-current-page))) (if (not (elpher-address-special-p address)) (let ((bookmark-display-string (read-string "Bookmark display string: " display-string))) @@ -1096,9 +1855,9 @@ host, selector and port." (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))) + (let* ((page (button-get button 'elpher-page)) + (address (elpher-page-address page)) + (display-string (elpher-page-display-string page))) (if (not (elpher-address-special-p address)) (let ((bookmark-display-string (read-string "Bookmark display string: " display-string))) @@ -1109,10 +1868,11 @@ host, selector and port." (error "No link selected")))) (defun elpher-unbookmark-current () - "Remove bookmark for the current node." + "Remove bookmark for the current page." (interactive) - (let ((address (elpher-node-address elpher-current-node))) - (unless (elpher-address-special-p address) + (let ((address (elpher-page-address elpher-current-page))) + (when (and (not (elpher-address-special-p address)) + (y-or-n-p "Really remove bookmark for the current page? ")) (elpher-remove-address-bookmark address) (message "Bookmark removed.")))) @@ -1121,49 +1881,47 @@ host, selector and port." (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.")) + (when (y-or-n-p "Really remove bookmark for this link? ") + (let ((page (button-get button 'elpher-page))) + (elpher-remove-address-bookmark (elpher-page-address page)) + (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 (not (elpher-address-special-p address)) - (message "`%s' on %s port %s" - (elpher-address-selector address) - (elpher-address-host address) - (elpher-address-port address)) - (message "%s" display-string)))) + (switch-to-buffer elpher-buffer-name) + (elpher-visit-page + (elpher-make-page "Bookmarks Page" (elpher-make-special-address 'bookmarks)))) + +(defun elpher-info-page (page) + "Display information on PAGE." + (let ((display-string (elpher-page-display-string page)) + (address (elpher-page-address page))) + (if (elpher-address-special-p address) + (message "Special page: %s" display-string) + (message "%s" (elpher-address-to-url address))))) (defun elpher-info-link () - "Display information on node corresponding to link at point." + "Display information on page corresponding to link at point." (interactive) (let ((button (button-at (point)))) (if button - (elpher-info-node (button-get button 'elpher-node)) + (elpher-info-page (button-get button 'elpher-page)) (error "No item selected")))) (defun elpher-info-current () - "Display information on current node." + "Display information on current page." (interactive) - (elpher-info-node elpher-current-node)) + (elpher-info-page elpher-current-page)) -(defun elpher-copy-node-url (node) - "Copy URL representation of address of NODE to `kill-ring'." - (let ((address (elpher-node-address node))) +(defun elpher-copy-page-url (page) + "Copy URL representation of address of PAGE to `kill-ring'." + (let ((address (elpher-page-address page))) (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))) + (error (format "Cannot represent %s as URL" (elpher-page-display-string page))) + (let ((url (elpher-address-to-url address))) (message "Copied \"%s\" to kill-ring/clipboard." url) (kill-new url))))) @@ -1172,22 +1930,22 @@ host, selector and port." (interactive) (let ((button (button-at (point)))) (if button - (elpher-copy-node-url (button-get button 'elpher-node)) + (elpher-copy-page-url (button-get button 'elpher-page)) (error "No item selected")))) (defun elpher-copy-current-url () - "Copy URL of current node to `kill-ring'." + "Copy URL of current page to `kill-ring'." (interactive) - (elpher-copy-node-url elpher-current-node)) + (elpher-copy-page-url elpher-current-page)) -(defun elpher-set-coding-system () - "Specify an explicit character coding system." +(defun elpher-set-gopher-coding-system () + "Specify an explicit character coding system for gopher selectors." (interactive) - (let ((system (read-coding-system "Set coding system to use (default is to autodetect): " nil))) + (let ((system (read-coding-system "Set coding system to use for gopher (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).")))) + (message "Gopher coding system fixed to %s. (Reload to see effect)." system) + (message "Gopher coding system set to autodetect. (Reload to see effect).")))) ;;; Mode and keymap @@ -1197,14 +1955,17 @@ host, selector and port." (let ((map (make-sparse-keymap))) (define-key map (kbd "TAB") 'elpher-next-link) (define-key map (kbd "") 'elpher-prev-link) + (define-key map (kbd "C-M-i") 'elpher-prev-link) (define-key map (kbd "u") 'elpher-back) + (define-key map (kbd "U") 'elpher-back-to-start) + (define-key map [mouse-3] '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 "T") 'elpher-toggle-tls) - (define-key map (kbd "w") 'elpher-view-raw) + (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) @@ -1217,20 +1978,22 @@ host, selector and port." (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 + (define-key map (kbd "S") 'elpher-set-gopher-coding-system) + (define-key map (kbd "F") 'elpher-forget-current-certificate) + (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 "U") 'elpher-back-to-start + [mouse-3] 'elpher-back (kbd "g") 'elpher-go (kbd "o") 'elpher-go-current (kbd "r") 'elpher-redraw (kbd "R") 'elpher-reload (kbd "T") 'elpher-toggle-tls - (kbd "w") 'elpher-view-raw + (kbd ".") 'elpher-view-raw (kbd "d") 'elpher-download (kbd "D") 'elpher-download-current (kbd "m") 'elpher-jump @@ -1243,7 +2006,8 @@ host, selector and port." (kbd "x") 'elpher-unbookmark-link (kbd "X") 'elpher-unbookmark-current (kbd "B") 'elpher-bookmarks - (kbd "S") 'elpher-set-coding-system)) + (kbd "S") 'elpher-set-gopher-coding-system + (kbd "F") 'elpher-forget-current-certificate)) map) "Keymap for gopher client.") @@ -1252,26 +2016,355 @@ host, selector and port." This mode is automatically enabled by the interactive functions which initialize the gopher client, namely -`elpher', `elpher-go' and `elpher-bookmarks'.") +`elpher', `elpher-go' and `elpher-bookmarks'." + (setq-local elpher-current-page nil) + (setq-local elpher-history nil) + (setq-local elpher-buffer-name (buffer-name))) (when (fboundp 'evil-set-initial-state) (evil-set-initial-state 'elpher-mode 'motion)) +;;; Menu +;; + +(defun elpher-menu (&optional arg) + "Show a list of all your `elpher' buffers. +With an optional argument, add all the history items, too." + (interactive "P") + (switch-to-buffer (get-buffer-create "*Elpher Menu*")) + (elpher-menu-mode) + (elpher-menu-refresh arg) + (tabulated-list-print)) + +(defvar elpher-menu-mode-map + (let ((map (make-sparse-keymap)) + (menu-map (make-sparse-keymap))) + (set-keymap-parent map tabulated-list-mode-map) + (define-key map "v" 'Buffer-menu-select) + (define-key map "2" 'Buffer-menu-2-window) + (define-key map "1" 'Buffer-menu-1-window) + (define-key map "f" 'Buffer-menu-this-window) + (define-key map "e" 'Buffer-menu-this-window) + (define-key map "\C-m" 'elpher-menu-this-window) + (define-key map "o" 'elpher-menu-other-window) + (define-key map "\C-o" 'elpher-menu-switch-other-window) + (define-key map "c" 'elpher-menu-copy-current-url) + (define-key map "d" 'Buffer-menu-delete) + (define-key map "k" 'Buffer-menu-delete) + (define-key map "\C-k" 'Buffer-menu-delete) + (define-key map "\C-d" 'Buffer-menu-delete-backwards) + (define-key map "x" 'Buffer-menu-execute) + (define-key map " " 'next-line) + (define-key map "\177" 'Buffer-menu-backup-unmark) + (define-key map "u" 'Buffer-menu-unmark) + (define-key map "m" 'Buffer-menu-mark) + (define-key map "b" 'Buffer-menu-bury) + (define-key map (kbd "M-s a C-s") 'Buffer-menu-isearch-buffers) + (define-key map (kbd "M-s a M-C-s") 'Buffer-menu-isearch-buffers-regexp) + (define-key map (kbd "M-s a C-o") 'Buffer-menu-multi-occur) + (define-key map [mouse-2] 'Buffer-menu-mouse-select) + (define-key map [follow-link] 'mouse-face) + (define-key map [menu-bar elpher-menu-mode] (cons (purecopy "Elpher-Menu") menu-map)) + (bindings--define-key menu-map [quit] + '(menu-item "Quit" quit-window + :help "Remove the elpher menu from the display")) + (bindings--define-key menu-map [rev] + '(menu-item "Refresh" revert-buffer + :help "Refresh the *Elpher Menu* buffer contents")) + (bindings--define-key menu-map [s0] menu-bar-separator) + (bindings--define-key menu-map [sel] + '(menu-item "Select Marked" Buffer-menu-select + :help "Select this line's buffer; also display buffers marked with `>'")) + (bindings--define-key menu-map [bm2] + '(menu-item "Select Two" Buffer-menu-2-window + :help "Select this line's buffer, with previous buffer in second window")) + (bindings--define-key menu-map [bm1] + '(menu-item "Select Current" Buffer-menu-1-window + :help "Select this line's buffer, alone, in full frame")) + (bindings--define-key menu-map [ow] + '(menu-item "Select in Other Window" elpher-menu-other-window + :help "Select this line's buffer in other window, leaving buffer menu visible")) + (bindings--define-key menu-map [tw] + '(menu-item "Select in Current Window" elpher-menu-this-window + :help "Select this line's buffer in this window")) + (bindings--define-key menu-map [s2] menu-bar-separator) + (bindings--define-key menu-map [is] + '(menu-item "Regexp Isearch Marked Buffers..." Buffer-menu-isearch-buffers-regexp + :help "Search for a regexp through all marked buffers using Isearch")) + (bindings--define-key menu-map [ir] + '(menu-item "Isearch Marked Buffers..." Buffer-menu-isearch-buffers + :help "Search for a string through all marked buffers using Isearch")) + (bindings--define-key menu-map [mo] + '(menu-item "Multi Occur Marked Buffers..." Buffer-menu-multi-occur + :help "Show lines matching a regexp in marked buffers using Occur")) + (bindings--define-key menu-map [s3] menu-bar-separator) + (bindings--define-key menu-map [by] + '(menu-item "Bury" Buffer-menu-bury + :help "Bury the buffer listed on this line")) + (bindings--define-key menu-map [ex] + '(menu-item "Execute" Buffer-menu-execute + :help "Delete buffers marked with k commands")) + (bindings--define-key menu-map [s4] menu-bar-separator) + (bindings--define-key menu-map [delb] + '(menu-item "Mark for Delete and Move Backwards" Buffer-menu-delete-backwards + :help "Mark buffer on this line to be deleted by x command and move up one line")) + (bindings--define-key menu-map [del] + '(menu-item "Mark for Delete" Buffer-menu-delete + :help "Mark buffer on this line to be deleted by x command")) + (bindings--define-key menu-map [umk] + '(menu-item "Unmark" Buffer-menu-unmark + :help "Cancel all requested operations on buffer on this line and move down")) + (bindings--define-key menu-map [mk] + '(menu-item "Mark" Buffer-menu-mark + :help "Mark buffer on this line for being displayed by v command")) + map) + "Local keymap for `elpher-menu-mode' buffers.") + +(define-derived-mode elpher-menu-mode tabulated-list-mode "Elpher Menu" + "Major mode for Elpher Menu buffers. +The Elpher Menu is invoked by the command \\[elpher-menu]. When +invoked with a prefix, the command also shows history items. +Since history items are no longer showing in a buffer, many of +the commands shown below will not work on them. + +In Elpher Menu mode, the following commands are defined: +\\ +\\[quit-window] Remove the Buffer Menu from the display. +\\[tabulated-list-sort] Sorts buffers according to the current + column. With a numerical argument, sort by that column. +\\[elpher-menu-this-window] Select current line's buffer in place of the buffer menu. +\\[elpher-menu-other-window] Select that buffer in another window, + so the Buffer Menu remains visible in its window. +\\[elpher-menu-switch-other-window] Make another window display that buffer. +\\[Buffer-menu-mark] Mark current line's buffer to be displayed. +\\[Buffer-menu-select] Select current line's buffer. + Also show buffers marked with m, in other windows. +\\[Buffer-menu-1-window] Select that buffer in full-frame window. +\\[Buffer-menu-2-window] Select that buffer in one window, together with the + buffer selected before this one in another window. +\\[Buffer-menu-isearch-buffers] Incremental search in the marked buffers. +\\[Buffer-menu-isearch-buffers-regexp] Isearch for regexp in the marked buffers. +\\[Buffer-menu-multi-occur] Show lines matching regexp in the marked buffers. +\\[Buffer-menu-delete] Mark that buffer to be deleted, and move down. +\\[Buffer-menu-delete-backwards] Mark that buffer to be deleted, and move up. +\\[Buffer-menu-execute] Delete or save marked buffers. +\\[Buffer-menu-unmark] Remove all marks from current line. + With prefix argument, also move up one line. +\\[Buffer-menu-backup-unmark] Back up a line and remove marks. +\\[revert-buffer] Update the list of buffers. +\\[Buffer-menu-bury] Bury the buffer listed on this line." + (add-hook 'tabulated-list-revert-hook 'elpher-menu-refresh nil t)) + +(defun elpher-menu-this-window () + "Select this line’s buffer in this window. +Switch to the buffer, if possible. If there is no buffer, chances +are that we're looking at a history item. Let's visit the item +instead of complaining that their buffers have been killed." + (interactive) + (elpher-menu-handle-buffer-or-data 'switch-to-buffer)) + +(defun elpher-menu-other-window () + "Select this line’s buffer in other window, leaving buffer menu visible." + (interactive) + (elpher-menu-handle-buffer-or-data 'switch-to-buffer-other-window)) + +(defun elpher-menu-switch-other-window () + "Make the other window select this line's buffer. +The current window remains selected." + (interactive) + (elpher-menu-handle-buffer-or-data + (lambda (buf) (display-buffer buf t)))) + +(defun elpher-menu-handle-buffer-or-data (buffer-func) + "Handle an item in `elpher-menu-mode'. +Determine the entry ID of the Tabulated List entry at point. If +ID is a buffer, invoke BUFFER-FUNC on it. Otherwise, ID is a +list (BUFFER FUNC ARGS...). Switch to BUFFER using BUFFER-FUNC +and apply FUNC to ARGS." + (let ((data (tabulated-list-get-id))) + (cond ((bufferp data) + (funcall buffer-func data)) + ((and (listp data) + (buffer-live-p (nth 0 data)) + (fboundp (nth 1 data))) + (funcall buffer-func (nth 0 data)) + (apply (nth 1 data) (nthcdr 2 data))) + (t + (error "There's no entry on this line of the menu"))))) + +(defun elpher-menu-copy-current-url () + "Copy the URL of the current menu item." + (interactive) + (let ((data (tabulated-list-get-id))) + (cond ((bufferp data) + (with-current-buffer data + (elpher-copy-page-url elpher-current-page))) + ((listp data) + (elpher-copy-page-url (nth 2 data))) + (t + (error "There's no entry on this line of the menu"))))) + + (defun elpher-copy-current-url () + "Copy URL of current page to `kill-ring'." + (interactive) + (elpher-copy-page-url elpher-current-page)) + +(defvar elpher-title nil) + +(defun elpher-find-title () + "Return the first heading1." + (if elpher-title + elpher-title + (let ((start (text-property-any + (point-min) (point-max) + 'face 'elpher-gemini-heading1))) + (when start + (save-excursion + (goto-char start) + (setq-local elpher-title + (buffer-substring-no-properties + start (line-end-position)))))))) + +(defun elpher-menu-refresh (&optional arg) + "Refresh the list of buffers. +With an optional argument, add all the history items, too. Note +that there are no buffers for history items so many of the buffer +menu commands won't work on them." + (setq tabulated-list-format + (vector '("T" 1 t) + '("Name" 30 t) + '("URL" 40 t)) + tabulated-list-sort-key nil) + ;; Collect info for each buffer we're interested in. + (let (entries) + (dolist (buf (buffer-list)) + (with-current-buffer buf + (when (memq major-mode '(elpher-mode eww-mode gemini-mode)) + (if arg + (setq entries (nconc (elpher-menu-refresh-history) entries)) + (push (elpher-menu-refresh-current) entries))))) + (setq tabulated-list-entries (nreverse entries))) + (tabulated-list-init-header)) + +(defun elpher-menu-refresh-current () + "Returns an item for `elpher-menu-refresh' +based on the current buffer. + +An item is a list (BUFFER VECTOR) where BUFFER is the buffer this +item refers to and VECTOR is what to display in the tabulated +list established by `elpher-menu-refresh'. See +`tabulated-list-format'." + (list (current-buffer) + (cond ((eq major-mode 'elpher-mode) + (vector "G" + (or (elpher-find-title) + (elpher-page-display-string elpher-current-page) + (buffer-name)) + (or (elpher-address-to-url + (elpher-page-address elpher-current-page)) + "none"))) + ((eq major-mode 'gemini-mode) + (vector "E" + (or (elpher-page-display-string elpher-current-page) + (buffer-name)) + (or (elpher-address-to-url + (elpher-page-address elpher-current-page)) + "none"))) + ((eq major-mode 'eww-mode) + (vector "W" + (or (plist-get eww-data :title) + (buffer-name)) + (or (eww-current-url) + "none")))))) + +(defun elpher-menu-refresh-history () + "Return current entries for `elpher-menu-refresh'. +This returns a list of items for the current buffer, based on the +buffer's history. + +An item is a list (BUFFER VECTOR) where BUFFER is the buffer this +item refers to and VECTOR is what to display in the tabulated +list established by `elpher-menu-refresh'. See +`tabulated-list-format'." + ;; Every section starts with the current page, followed by some + ;; history items, and ends with the separator. + (let ((separator (list nil + (vector "-" + (make-string 25 ?-) + (make-string 25 ?-))))) + (cond ((eq major-mode 'elpher-mode) + ;; A pair is (BUFFER-OR-DATA . PAGE) where BUFFER-OR-DTA is + ;; the current buffer, if possible, or list (BUFFER FUNC + ;; &rest ARGS) telling us which BUFFER to switch to, and + ;; what function to call. The last item of elpher-history + ;; has a nil page, so when that shows up, use the separator + (mapcar (lambda (pair) + (if (cdr pair) + (list (car pair) + (vector "G" + (or (elpher-page-display-string (cdr pair)) "?") + (or (elpher-address-to-url + (elpher-page-address (cdr pair))) "none"))) + separator)) + (cons (cons (current-buffer) elpher-current-page) + (mapcar (lambda (page) + (cons (list (current-buffer) 'elpher-visit-page page) + page)) + elpher-history)))) + ((eq major-mode 'gemini-mode) + ;; No history means a list of one item. Add a separator. + (list (list (current-buffer) + (vector "E" + (or (elpher-page-display-string elpher-current-page) + (buffer-name)) + (or (elpher-address-to-url + (elpher-page-address elpher-current-page))))) + separator)) + ((eq major-mode 'eww-mode) + ;; A pair is (BUFFER-OR-DATA . PAGE) where BUFFER-OR-DTA is + ;; the current buffer, if possible, or list (BUFFER FUNC + ;; &rest ARGS) telling us which BUFFER to switch to, and + ;; what function to call. Add the separator at the end. + (nconc (cons (list (current-buffer) + (vector "W" + (or (plist-get eww-data :title) "none") + (or (plist-get eww-data :url) "none"))) + (mapcar (lambda (data) + (list + (list (current-buffer) 'eww-restore-history data) + (vector "W" + (or (plist-get data :title) "none") + (or (plist-get data :url) "none")))) + eww-history)) + (list separator)))))) ;;; Main start procedure ;; ;;;###autoload -(defun elpher () - "Start elpher with default landing page." - (interactive) - (if (get-buffer "*elpher*") - (switch-to-buffer "*elpher*") - (switch-to-buffer "*elpher*") - (setq elpher-current-node nil) - (let ((start-node (elpher-make-node "Elpher Start Page" - (elpher-make-address 'start)))) - (elpher-visit-node start-node))) - "Started Elpher.") ; Otherwise (elpher) evaluates to start page string. +(defun elpher (&optional arg) + "Start elpher with default landing page. +The buffer used for Elpher sessions is determined by the value of +‘elpher-buffer-name’. If there is already an Elpher session active in +that buffer, Emacs will simply switch to it. Otherwise, a new session +will begin. A numeric prefix arg (as in ‘C-u 42 M-x elpher RET’) +switches to the session with that number, creating it if necessary. A +nonnumeric prefix arg means to create a new session. Returns the +buffer selected (or created)." + (interactive "P") + (let* ((name (default-value 'elpher-buffer-name)) + (buf (cond ((numberp arg) + (get-buffer-create (format "%s<%d>" name arg))) + (arg + (generate-new-buffer name)) + (t + (get-buffer-create name))))) + (pop-to-buffer-same-window buf) + (unless (buffer-modified-p) + (elpher-mode) + (let ((start-page (elpher-make-page "Elpher Start Page" + (elpher-make-special-address 'start)))) + (elpher-visit-page start-page)) + "Started Elpher."))); Otherwise (elpher) evaluates to start page string. ;;; elpher.el ends here