X-Git-Url: https://thelambdalab.xyz/gitweb/index.cgi?p=elpher.git;a=blobdiff_plain;f=elpher.el;h=a3ff573a2385994e8729bffad4da94cb8b1ceaa4;hp=acb7083e3ceff81a814b5b7d821fc76a7db643ad;hb=1d6fca7dc2254ac37d4f2984823e5b887f8bde56;hpb=c0ff9d26c2e5cf62ade93852e7eb8a0f081bf028 diff --git a/elpher.el b/elpher.el index acb7083..a3ff573 100644 --- a/elpher.el +++ b/elpher.el @@ -4,7 +4,7 @@ ;; Author: Tim Vaughan ;; Created: 11 April 2019 -;; Version: 2.3.5 +;; Version: 2.3.6 ;; Keywords: comm gopher ;; Homepage: https://github.com/tgvaughan/elpher ;; Package-Requires: ((emacs "26")) @@ -60,12 +60,13 @@ (require 'shr) (require 'url-util) (require 'subr-x) +(require 'dns) ;;; Global constants ;; -(defconst elpher-version "2.3.5" +(defconst elpher-version "2.3.6" "Current version of elpher.") (defconst elpher-margin-width 6 @@ -88,7 +89,7 @@ (gemini elpher-get-gemini-node elpher-render-gemini "gem" elpher-gemini) (telnet elpher-get-telnet-node nil "tel" elpher-telnet) (other-url elpher-get-other-url-node nil "url" elpher-other-url) - ((special bookmarks) elpher-get-bookmarks-node nil) + ((special bookmarks) elpher-get-bookmarks-node nil "/" elpher-index) ((special start) elpher-get-start-node nil)) "Association list from types to getters, renderers, margin codes and index faces.") @@ -175,6 +176,9 @@ 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)) ;;; Model ;; @@ -282,16 +286,11 @@ For gopher addresses this is a combination of the selector type and selector." (url-host address)) (defun elpher-address-port (address) - "Retrieve port from ADDRESS object." + "Retrieve port from ADDRESS object. +If no address is defined, returns 0. (This is for compatibility with the URL library.)" (if (symbolp address) - nil) - (if (> (url-port address) 0) - (url-port address) - (or (and (or (equal (url-type address) "gopher") - (equal (url-type address) "gophers")) - 70) - (and (equal (url-type address) "gemini") - 1965)))) + 0 + (url-port address))) (defun elpher-address-special-p (address) "Return non-nil if ADDRESS object is special (e.g. start page, bookmarks page)." @@ -426,11 +425,13 @@ unless PRESERVE-PARENT is non-nil." (if elpher-use-header (let* ((display-string (elpher-node-display-string elpher-current-node)) (address (elpher-node-address elpher-current-node)) - (url-string (if (elpher-address-special-p address) - "" - (concat " - " (elpher-address-to-url address) ""))) - (header (replace-regexp-in-string "%" "%%" (concat display-string - url-string)))) + (tls-string (if (and (not (elpher-address-special-p address)) + (member (elpher-address-protocol address) + '("gophers" "gemini"))) + " [TLS encryption]" + "")) + (header (concat display-string + (propertize tls-string 'face 'bold)))) (setq header-line-format header)))) (defmacro elpher-with-clean-buffer (&rest args) @@ -468,11 +469,12 @@ away CRs and any terminating period." ;; (defun elpher-network-error (address error) - "Display ERROR message following unsuccessful negotiation with ADDRESS." + "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" - (error-message-string error) "\n" + (if (stringp error) error (error-message-string error)) "\n" (propertize "\n----------------\n\n" 'face 'error) "Press 'u' to return to the previous page."))) @@ -480,65 +482,86 @@ away CRs and any terminating period." ;;; Gopher selector retrieval ;; +(defvar elpher-network-timer nil + "Timer used for network connections.") + (defun elpher-process-cleanup () - "Immediately shut down any extant elpher process." + "Immediately shut down any extant elpher process and timers." (let ((p (get-process "elpher-process"))) - (if p (delete-process p)))) + (if p (delete-process p))) + (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.") -(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 "") +(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"))) - (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) - (let ((inhibit-eol-conversion t)) - (process-send-string proc - (concat (elpher-gopher-address-selector address) "\r\n")))) - (error - (if (and (consp the-error) - (eq (car the-error) 'gnutls-error) - (not (equal (elpher-address-protocol address) "gophers")) - (or elpher-auto-disengage-TLS - (yes-or-no-p "Could not establish encrypted connection. Disable TLS mode? "))) - (progn - (message "Disengaging TLS gopher mode.") - (setq elpher-use-tls nil) - (elpher-get-selector address after)) - (elpher-process-cleanup) - (if propagate-error - (error the-error) - (elpher-with-clean-buffer - (insert (propertize "\n---- ERROR -----\n\n" 'face 'error) - "Failed to connect to " (elpher-address-to-url address) ".\n" - (propertize "\n----------------\n\n" 'face 'error) - "Press 'u' to return to the previous page."))))))) + (if (gnutls-available-p) + (when (not elpher-use-tls) + (setq elpher-use-tls t) + (message "Engaging TLS gopher mode.")) + (elpher-network-error "Cannot retrieve TLS gopher selector: GnuTLS not available"))) + (unless (< (elpher-address-port address) 65536) + (elpher-network-error "Cannot retrieve gopher selector: port number > 65536")) + (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 + (error-message-string the-error)))))))) (defun elpher-get-gopher-node (renderer) "Getter function for gopher nodes. @@ -552,11 +575,7 @@ once they are retrieved from the gopher server." (elpher-restore-pos)) (elpher-with-clean-buffer (insert "LOADING... (use 'u' to cancel)")) - (elpher-get-selector address - (lambda (_proc event) - (unless (string-prefix-p "deleted" event) - (funcall renderer elpher-selector-string) - (elpher-restore-pos))))))) + (elpher-get-selector address renderer)))) ;; Index rendering @@ -594,7 +613,9 @@ once they are retrieved from the gopher server." (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))) - (format "mouse-1, RET: open '%s'" (elpher-address-to-url address)))) + (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. @@ -654,7 +675,7 @@ If ADDRESS is not supplied or nil the record is rendered as an (insert string) (goto-char (point-min)) (while (re-search-forward elpher-url-regex nil t) - (let ((node (elpher-make-node (match-string 0) + (let ((node (elpher-make-node (substring-no-properties (match-string 0)) (elpher-address-from-url (match-string 0))))) (make-text-button (match-beginning 0) (match-end 0) @@ -716,21 +737,19 @@ The response is rendered using the rendering function RENDERER." (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) - (funcall renderer elpher-selector-string) - (elpher-restore-pos))))) + (elpher-get-selector search-address renderer)) (if aborted (elpher-visit-parent-node)))))) ;; Raw server response rendering -(defun elpher-render-raw (data &optional _mime-type-string) - "Display raw DATA in buffer. MIME-TYPE-STRING is unused." +(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 + (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."))) @@ -769,36 +788,71 @@ The response is rendered using the rendering function RENDERER." ;; Gemini node retrieval -(defvar elpher-gemini-response) +(defvar elpher-gemini-redirect-chain) -(defun elpher-get-gemini-response (address after) - "Retrieve gemini ADDRESS, then execute AFTER. -The response is stored in the variable ‘elpher-gemini-response’." - (setq elpher-gemini-response "") +(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") - (condition-case the-error + (unless (< (elpher-address-port address) 65536) + (error "Cannot establish gemini connection: port number > 65536")) + (condition-case _the-error (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 - (elpher-address-host address) - (elpher-address-port address) - :type 'tls))) + (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) - (setq elpher-gemini-response - (concat elpher-gemini-response string)))) - (set-process-sentinel proc after) - (let ((inhibit-eol-conversion t)) - (process-send-string proc - (concat (elpher-address-to-url address) "\r\n")))) + (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-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 + "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 @@ -811,53 +865,46 @@ that the response was malformed." (error "Malformed response: No response status found in header %s" header))) (error "Malformed response: No CRLF-delimited header found")))) - -(defun elpher-process-gemini-response (renderer) - "Process the gemini response and pass the result to RENDERER. -The response is assumed to be in the variable `elpher-gemini-response'." - (condition-case the-error - (let ((response-components (elpher-parse-gemini-response elpher-gemini-response))) - (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 (read-string (concat response-meta ": "))) - (url (elpher-address-to-url (elpher-node-address elpher-current-node))) - (query-address (elpher-address-from-url (concat url "?" query-string)))) - (elpher-get-gemini-response query-address - (lambda (_proc event) - (unless (string-prefix-p "deleted" event) - (funcall #'elpher-process-gemini-response - renderer) - (elpher-restore-pos)))))) - (?2 ; Normal response - ;; (message response-header) - (funcall renderer response-body response-meta)) - (?3 ; Redirect - (message "Following redirect to %s" response-meta) - (let ((redirect-address (elpher-address-from-gemini-url response-meta))) - (elpher-get-gemini-response redirect-address - (lambda (_proc event) - (unless (string-prefix-p "deleted" event) - (funcall #'elpher-process-gemini-response - renderer) - (elpher-restore-pos)))))) - (?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 - (error "Gemini server requires client certificate (unsupported at this time)")) - (_other - (error "Gemini server response unknown: %s %s" - response-code response-meta))))) - (error - (elpher-network-error (elpher-node-address elpher-current-node) the-error)))) +(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 (read-string (concat response-meta ": "))) + (url (elpher-address-to-url (elpher-node-address elpher-current-node))) + (query-address (elpher-address-from-url (concat url "?" 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)) + (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 + (error "Gemini server requires client certificate (unsupported at this time)")) + (_other + (error "Gemini server response unknown: %s %s" + response-code response-meta)))))) (defun elpher-get-gemini-node (renderer) "Getter which retrieves and renders a Gemini node and renders it using RENDERER." @@ -870,12 +917,8 @@ The response is assumed to be in the variable `elpher-gemini-response'." (elpher-restore-pos)) (elpher-with-clean-buffer (insert "LOADING GEMINI... (use 'u' to cancel)")) - (elpher-get-gemini-response address - (lambda (_proc event) - (unless (string-prefix-p "deleted" event) - (funcall #'elpher-process-gemini-response - renderer) - (elpher-restore-pos))))) + (setq elpher-gemini-redirect-chain nil) + (elpher-get-gemini-response address renderer)) (error (elpher-network-error address the-error))))) @@ -905,6 +948,8 @@ The response is assumed to be in the variable `elpher-gemini-response'." (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/")) @@ -942,7 +987,9 @@ For instance, the filename /a/b/../c/./d will reduce to /a/c/d" (let ((address (url-generic-parse-url url))) (unless (and (url-type address) (not (url-fullness address))) ;avoid mangling mailto: urls (setf (url-fullness address) t) - (unless (url-host address) ;if there is an explicit host, filenames are absolute + (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-node-address elpher-current-node))) (unless (string-prefix-p "/" (url-filename address)) ;deal with relative links (setf (url-filename address) @@ -1007,7 +1054,9 @@ For instance, the filename /a/b/../c/./d will reduce to /a/c/d" (host (elpher-address-host address)) (port (elpher-address-port address))) (elpher-visit-parent-node) - (telnet host port))) + (if (> port 0) + (telnet host port) + (telnet host)))) ;; Start page node retrieval @@ -1049,6 +1098,9 @@ For instance, the filename /a/b/../c/./d will reduce to /a/c/d" "Alternatively, select the following item and enter some search terms:\n") (elpher-insert-index-record "Veronica-2 Gopher Search Engine" (elpher-make-gopher-address ?7 "/v2/vs" "gopher.floodgap.com" 70)) + (insert "\n" + "This page contains your bookmarked sites (also visit with B):\n") + (elpher-insert-index-record "Your Bookmarks" 'bookmarks) (insert "\n" "** Refer to the ") (let ((help-string "RET,mouse-1: Open Elpher info manual (if available)")) @@ -1082,12 +1134,23 @@ For instance, the filename /a/b/../c/./d will reduce to /a/c/d" (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 (locate-user-emacs-file "elpher-bookmarks")) + (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)))