-;;; elpher.el --- A friendly gopher client. -*- lexical-binding:t -*-
+;;; 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 <tgvaughan@gmail.com>
+;; Author: Tim Vaughan <plugd@thelambdalab.xyz>
;; Created: 11 April 2019
-;; Version: 2.4.4
+;; Version: 2.8.0
;; Keywords: comm gopher
;; Homepage: http://thelambdalab.xyz/elpher
-;; Package-Requires: ((emacs "26"))
+;; Package-Requires: ((emacs "26.1"))
;; This file is not part of GNU Emacs.
;;; 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,
;; - pleasant and configurable colouring of Gopher directories,
;; - direct visualisation of image files,
;; - a simple bookmark management system,
-;; - connections using TLS encryption,
-;; - support for the fledgling Gemini protocol.
+;; - 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
(require 'url-util)
(require 'subr-x)
(require 'dns)
+(require 'ansi-color)
+(require 'nsm)
+(require 'gnutls)
;;; Global constants
;;
-(defconst elpher-version "2.4.4"
+(defconst elpher-version "2.8.0"
"Current version of elpher.")
(defconst elpher-margin-width 6
((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)
"A gopher 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-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.")
(defface elpher-gemini
'((t :inherit font-lock-regexp-grouping-backslash))
- "Face used for html type directory records.")
+ "Face used for Gemini type directory records.")
(defface elpher-other-url
'((t :inherit font-lock-comment-face))
'((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 t
- "If non-nil, turns URLs matched in directories into clickable buttons."
- :type '(boolean))
-
-(defcustom elpher-use-header t
- "If non-nil, display current page information in buffer header."
- :type '(boolean))
+(defface elpher-gemini-heading1
+ '((t :inherit bold :height 1.8))
+ "Face used for gemini heading level 1.")
-(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-heading2
+ '((t :inherit bold :height 1.5))
+ "Face used for gemini heading level 2.")
-(defcustom elpher-connection-timeout 5
- "Specifies the number of seconds to wait for a network connection to time out."
- :type '(integer))
+(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
;;
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)))
(defun elpher-address-to-url (address)
"Get string representation of ADDRESS, or nil if ADDRESS is special."
- (if (not (elpher-address-special-p address))
- (url-encode-url (url-recreate-url address))
- nil))
+ (if (elpher-address-special-p address)
+ nil
+ (url-encode-url (url-recreate-url address))))
(defun elpher-address-type (address)
"Retrieve type of ADDRESS object.
'gemini)
((equal protocol "telnet")
'telnet)
+ ((equal protocol "finger")
+ 'finger)
(t 'other-url)))))
(defun elpher-address-protocol (address)
"Retrieve host from ADDRESS object."
(url-host address))
+(defun elpher-address-user (address)
+ "Retrieve user from ADDRESS object."
+ (url-user address))
+
(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.)"
"Retrieve gopher selector from ADDRESS object."
(if (member (url-filename address) '("" "/"))
""
- (substring (url-filename address) 2)))
+ (url-unhex-string (substring (url-filename address) 2))))
;; Cache
;; 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)
(defvar elpher-history nil)
(let ((previous-page (pop elpher-history)))
(if previous-page
(elpher-visit-page previous-page nil t)
- (error "No previous page."))))
+ (error "No previous page"))))
(defun elpher-reload-current-page ()
"Reload the current page, discarding any existing cached content."
(list 'with-current-buffer "*elpher*"
'(elpher-mode)
(append (list '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*"
+ (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
;;
"Press 'u' to return to the previous page.")))
-;;; Gopher selector retrieval
+;;; 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 (timerp elpher-network-timer)
(cancel-timer elpher-network-timer)))
-(defvar elpher-use-tls nil
- "If non-nil, use TLS to communicate with gopher servers.")
+(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 "..."))
+ (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..."))
+ (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")))))
-(defun elpher-get-selector (address renderer &optional force-ipv4)
- "Retrieve selector specified by ADDRESS, then render it using RENDERER.
-If FORCE-IPV4 is non-nil, explicitly look up and use IPv4 address corresponding
-to ADDRESS."
- (when (equal (elpher-address-protocol address) "gophers")
- (if (gnutls-available-p)
- (when (not elpher-use-tls)
- (setq elpher-use-tls t)
- (message "Engaging TLS gopher mode."))
- (error "Cannot retrieve TLS gopher selector: GnuTLS not available")))
- (unless (< (elpher-address-port address) 65536)
- (error "Cannot retrieve gopher selector: port number > 65536"))
- (condition-case nil
- (let* ((kill-buffer-query-functions nil)
- (port (elpher-address-port address))
- (host (elpher-address-host address))
- (selector-string "")
- (proc (open-network-stream "elpher-process"
- nil
- (if force-ipv4 (dns-query host) host)
- (if (> port 0) port 70)
- :type (if elpher-use-tls 'tls 'plain)
- :nowait t))
- (timer (run-at-time elpher-connection-timeout
- nil
- (lambda ()
- (pcase (process-status proc)
- ('failed
- (if (and (not (equal (elpher-address-protocol address)
- "gophers"))
- elpher-use-tls
- (or elpher-auto-disengage-TLS
- (yes-or-no-p "Could not establish encrypted connection. Disable TLS mode?")))
- (progn
- (message "Disabling TLS mode.")
- (setq elpher-use-tls nil)
- (elpher-get-selector address renderer))
- (elpher-network-error address "Could not establish encrypted connection")))
- ('connect
- (elpher-process-cleanup)
- (unless force-ipv4
- (message "Connection timed out. Retrying with IPv4 address.")
- (elpher-get-selector address renderer t))))))))
- (setq elpher-network-timer timer)
- (set-process-coding-system proc 'binary)
- (set-process-filter proc
- (lambda (_proc string)
- (cancel-timer timer)
- (setq selector-string
- (concat selector-string string))))
- (set-process-sentinel proc
- (lambda (_proc event)
- (condition-case the-error
- (cond
- ((string-prefix-p "deleted" event))
- ((string-prefix-p "open" event)
- (let ((inhibit-eol-conversion t))
- (process-send-string
- proc
- (concat (elpher-gopher-address-selector address)
- "\r\n"))))
- (t
- (cancel-timer timer)
- (funcall renderer selector-string)
- (elpher-restore-pos)))
- (error
- (elpher-network-error address the-error))))))
- (error
- (error "Error initiating connection to server"))))
+(defun elpher-generate-certificate (name key-file cert-file &optional temporary)
+ (let ((exp-key-file (expand-file-name key-file))
+ (exp-cert-file (expand-file-name cert-file)))
+ (call-process "openssl" nil nil nil
+ "req" "-x509" "-newkey" "rsa:2048"
+ "-days" (if temporary "1" "36500")
+ "-nodes"
+ "-subj" (concat "/CN=" 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)))
+
+(defun elpher-generate-throwaway-certificate ()
+ (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-permanent-certificate (file-base)
+ (let* ((key-file (concat elpher-certificate-directory file-base ".key"))
+ (cert-file (concat elpher-certificate-directory file-base ".crt")))
+ (elpher-generate-certificate file-base key-file cert-file)))
+
+(defun elpher-get-existing-certificate (file-base)
+ (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-list-existing-certificates ()
+ (mapcar
+ (lambda (file)
+ (file-name-sans-extension file))
+ (directory-files elpher-certificate-directory nil "\.key$")))
+
+
+(defun elpher-get-current-keylist (address)
+ (if elpher-client-certificate
+ (if (string= (car elpher-client-certificate)
+ (elpher-address-host address))
+ (list (cddr elpher-client-certificate))
+ (when (cadr elpher-client-certificate)
+ (delete-file (elt elpher-client-certificate 2))
+ (delete-file (elt elpher-client-certificate 3)))
+ (setq elpher-client-certificate nil)
+ (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.
(insert content)
(elpher-restore-pos))
(elpher-with-clean-buffer
- (insert "LOADING... (use 'u' to cancel)"))
+ (insert "LOADING... (use 'u' to cancel)\n"))
(condition-case the-error
- (elpher-get-selector address renderer)
+ (elpher-get-gopher-response address renderer)
(error
(elpher-network-error address the-error))))))
(insert " "))
(insert (make-string elpher-margin-width ?\s))))
-(defun elpher-page-button-help (page)
- "Return a string containing the help text for a button corresponding to PAGE."
- (let ((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--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.
(if type-map-entry
(let* ((margin-code (elt type-map-entry 2))
(face (elt type-map-entry 3))
- (page (elpher-make-page display-string address)))
+ (filtered-display-string (ansi-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-page page
'action #'elpher-click-link
'follow-link t
- 'help-echo (elpher-page-button-help page)))
+ 'help-echo #'elpher--page-button-help))
(pcase type
- ((or '(gopher ?i) 'nil) ;; Information
+ ('nil ;; Information
(elpher-insert-margin)
(let ((propertized-display-string
(propertize display-string 'face 'elpher-info)))
- (insert (if elpher-buttonify-urls-in-directories
- (elpher-buttonify-urls propertized-display-string)
- propertized-display-string))))
+ (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
;; Text rendering
(defconst elpher-url-regex
- "\\([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 buttniofy URLs in text files loaded by elpher.")
+ "\\([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-buttonify-urls (string)
"Turn substrings which look like urls in STRING into clickable buttons."
'elpher-page page
'action #'elpher-click-link
'follow-link t
- 'help-echo (elpher-page-button-help page)
+ 'help-echo #'elpher--page-button-help
'face 'button)))
(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
+ (ansi-color-filter-apply string)
+ (ansi-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-buttonify-urls (elpher-preprocess-text-response data)))
+ (insert (elpher-process-text-for-display (elpher-preprocess-text-response data)))
(elpher-cache-content
(elpher-page-address elpher-current-page)
(buffer-string)))))
(elpher-with-clean-buffer
(insert "LOADING RESULTS... (use 'u' to cancel)"))
- (elpher-get-selector search-address renderer))
+ (elpher-get-gopher-response search-address renderer))
(if aborted
(elpher-visit-previous-page))))))
(if (not data)
nil
(let* ((address (elpher-page-address elpher-current-page))
- (selector (elpher-gopher-address-selector address)))
+ (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: "
(defvar elpher-gemini-redirect-chain)
-(defun elpher-get-gemini-response (address renderer &optional force-ipv4)
- "Retrieve gemini ADDRESS, then render using RENDERER.
-If FORCE-IPV4 is non-nil, explicitly look up and use IPv4 address corresponding
-to ADDRESS."
- (if (not (gnutls-available-p))
- (error "Cannot establish gemini connection: GnuTLS not available")
- (unless (< (elpher-address-port address) 65536)
- (error "Cannot establish gemini connection: port number > 65536"))
- (condition-case nil
- (let* ((kill-buffer-query-functions nil)
- (port (elpher-address-port address))
- (host (elpher-address-host address))
- (response-string "")
- (proc (open-network-stream "elpher-process"
- nil
- (if force-ipv4 (dns-query host) host)
- (if (> port 0) port 1965)
- :type 'tls
- :nowait t))
- (timer (run-at-time elpher-connection-timeout nil
- (lambda ()
- (elpher-process-cleanup)
- (unless force-ipv4
- ; Try again with IPv4
- (message "Connection timed out. Retrying with IPv4.")
- (elpher-get-gemini-response address renderer t))))))
- (setq elpher-network-timer timer)
- (set-process-coding-system proc 'binary)
- (set-process-filter proc
- (lambda (_proc string)
- (cancel-timer timer)
- (setq response-string
- (concat response-string string))))
- (set-process-sentinel proc
- (lambda (proc event)
- (condition-case the-error
- (cond
- ((string-prefix-p "open" event) ; request URL
- (let ((inhibit-eol-conversion t))
- (process-send-string
- proc
- (concat (elpher-address-to-url address)
- "\r\n"))))
- ((string-prefix-p "deleted" event)) ; do nothing
- ((and (string-empty-p response-string)
- (not force-ipv4))
- ; Try again with IPv4
- (message "Connection failed. Retrying with IPv4.")
- (cancel-timer timer)
- (elpher-get-gemini-response address renderer t))
- (t
- (funcall #'elpher-process-gemini-response
- response-string
- renderer)
- (elpher-restore-pos)))
- (error
- (elpher-network-error address the-error))))))
- (error
- (error "Error initiating connection to server")))))
+(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.
(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"))))
+ (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."
(elpher-with-clean-buffer
(insert "Gemini server is requesting input."))
(let* ((query-string (read-string (concat response-meta ": ")))
- (url (elpher-address-to-url (elpher-page-address elpher-current-page)))
- (query-address (elpher-address-from-url (concat url "?" query-string))))
+ (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))
"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 PERMANENT FAILURE for this request: %s %s"
response-code response-meta))
(?6 ; Client certificate required
- (error "Gemini server requires client certificate (unsupported at this time)"))
+ (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* ((read-answer-short t)
+ (res (read-answer "What do you want to do? "
+ '(("throwaway" ?t "generate and use throw-away certificate")
+ ("permanent" ?p "generate and use permanent certificate")
+ ("existing" ?e "use existing certificate")
+ ("abort" ?a "stop immediately")))))
+ (pcase res
+ ("throwaway"
+ (setq elpher-client-certificate (elpher-generate-throwaway-certificate)))
+ ("permanent"
+ (let ((file-base (read-string "Name for certificate: ")))
+ (setq elpher-client-certificate
+ (elpher-generate-permanent-certificate file-base))))
+ ("existing"
+ (let ((file-base (completing-read "Name of existing certificate (autocompletes, empty response aborts): "
+ (elpher-list-existing-certificates)
+ nil t)))
+ (if (string-empty-p file-base)
+ (error "Gemini server requires a client certificate and none was provided")
+ (setq elpher-client-certificate
+ (elpher-get-existing-certificate file-base)))))
+ ;; TODO
+ ("abort"
+ (error "Gemini server requires a client certificate and none was provided")))
+ (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))))))
(insert content)
(elpher-restore-pos))
(elpher-with-clean-buffer
- (insert "LOADING GEMINI... (use 'u' to cancel)"))
+ (insert "LOADING GEMINI... (use 'u' to cancel)\n"))
(setq elpher-gemini-redirect-chain nil)
(elpher-get-gemini-response address renderer))
(error
((pred (string-prefix-p "image/"))
(elpher-render-image body))
(_other
- (error "Unsupported MIME type %S" mime-type))))))
-
-(defun elpher-gemini-get-link-url (line)
- "Extract the url portion of LINE, a gemini map file link line."
- (string-trim (elt (split-string (substring line 2)) 0)))
-
-(defun elpher-gemini-get-link-display-string (line)
- "Extract the display string portion of LINE, a gemini map file link line."
- (let* ((rest (string-trim (elt (split-string line "=>") 1)))
+ (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)))
- (if idx
- (string-trim (substring rest (+ idx 1)))
- "")))
+ (string-trim (if idx
+ (substring rest (+ idx 1))
+ rest))))
(defun elpher-collapse-dot-sequences (filename)
"Collapse dot sequences in FILENAME.
(defun elpher-address-from-gemini-url (url)
"Extract address from URL with defaults as per gemini map files."
- (let ((address (url-generic-parse-url url)))
+ (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 (elpher-page-address elpher-current-page)))
+ (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 (elpher-page-address elpher-current-page)))
+ (concat (file-name-directory (url-filename current-address))
(url-filename address)))))
(unless (url-type address)
(setf (url-type address) "gemini"))
(elpher-collapse-dot-sequences (url-filename address)))))
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 (ansi-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))))
+ (unless (display-graphic-p)
+ (insert (make-string level ?#) " "))
+ (insert (propertize header 'face
+ (pcase level
+ (1 'elpher-gemini-heading1)
+ (2 'elpher-gemini-heading2)
+ (3 'elpher-gemini-heading3)
+ (_ 'default)))
+ "\n"))))
+
+(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
- (dolist (line (split-string data "\n"))
- (if (string-prefix-p "=>" line)
- (let* ((url (elpher-gemini-get-link-url line))
- (display-string (elpher-gemini-get-link-display-string line))
- (address (elpher-address-from-gemini-url url)))
- (if (> (length display-string) 0)
- (elpher-insert-index-record display-string address)
- (elpher-insert-index-record url address)))
- (elpher-insert-index-record line)))
+ (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-buttonify-urls data))
+ (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
+ (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
+ (elpher-network-error address the-error))))))
+
+
;; Other URL page opening
(defun elpher-get-other-url-page (renderer)
(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"
" - 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/mouse-3: 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"
" - T: toggle TLS gopher mode\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-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 the following item and enter some search terms:\n")
- (elpher-insert-index-record "Veronica-2 Gopher Search Engine"
+ "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"
"This page contains your bookmarked sites (also visit with B):\n")
(elpher-insert-index-record "Your Bookmarks" 'bookmarks)
"- a: rename selected bookmark\n"
"\n"
"Bookmarks are stored in the file ")
- (let ((filename (locate-user-emacs-file "elpher-bookmarks"))
+ (let ((filename elpher-bookmarks-file)
(help-string "RET,mouse-1: Open bookmarks file in new buffer for editing."))
(insert-text-button filename
'face 'link
(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 bookmarks file\n\n"
"; Bookmarks are stored as a list of (label URL) items.\n"
(let ((bookmarks
(with-temp-buffer
(ignore-errors
- (insert-file-contents (locate-user-emacs-file "elpher-bookmarks"))
+ (insert-file-contents elpher-bookmarks-file)
(goto-char (point-min))
(read (current-buffer))))))
(if (and bookmarks (listp (cadar bookmarks)))
(interactive)
(push-button))
-(defun elpher-go ()
- "Go to a particular gopher site read from the minibuffer."
- (interactive)
- (let ((page
- (let ((host-or-url (read-string "Gopher or Gemini URL: ")))
- (elpher-make-page host-or-url
- (elpher-address-from-url host-or-url)))))
+(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*")
- (elpher-visit-page page)))
+ (elpher-visit-page page)
+ nil))
(defun elpher-go-current ()
"Go to a particular site read from the minibuffer, initialized with the current URL."
(interactive)
(elpher-visit-previous-page))
+(defun elpher-back-to-start ()
+ "Go all the way back to the start page."
+ (interactive)
+ (setq elpher-current-page nil)
+ (setq 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)
(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-current-page)
+ (elpher-page-address elpher-current-page))
#'elpher-render-download
t)))
(let ((address-copy (elpher-address-from-url
(elpher-address-to-url address))))
(setf (url-filename address-copy) "")
- (elpher-visit-page
- (elpher-make-page (elpher-address-to-url address-copy)
- 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 ()
"Remove bookmark for the current page."
(interactive)
(let ((address (elpher-page-address elpher-current-page)))
- (unless (elpher-address-special-p address)
+ (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."))))
(interactive)
(let ((button (button-at (point))))
(if button
- (let ((page (button-get button 'elpher-page)))
- (elpher-remove-address-bookmark (elpher-page-address page))
- (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 ()
(let ((map (make-sparse-keymap)))
(define-key map (kbd "TAB") 'elpher-next-link)
(define-key map (kbd "<backtab>") '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)
(kbd "C-") 'elpher-follow-current-link
(kbd "C-t") 'elpher-back
(kbd "u") 'elpher-back
+ (kbd "U") 'elpher-back-to-start
[mouse-3] 'elpher-back
(kbd "g") 'elpher-go
(kbd "o") 'elpher-go-current
(switch-to-buffer "*elpher*")
(switch-to-buffer "*elpher*")
(setq elpher-current-page nil)
+ (setq elpher-history nil)
(let ((start-page (elpher-make-page "Elpher Start Page"
(elpher-make-special-address 'start))))
(elpher-visit-page start-page)))