;;
(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.")))
;;
(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)
+(defvar elpher-network-timer)
(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."
- (setq elpher-selector-string "")
(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")))
+ (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)
(timer (run-at-time elpher-connection-timeout
nil
(lambda ()
- (message "timeout (status %s)" (process-status proc))
(pcase (process-status proc)
('failed
(if (and (not (equal (elpher-address-protocol address)
(progn
(message "Disabling TLS mode.")
(setq elpher-use-tls nil)
- (elpher-get-selector address renderer))))
+ (elpher-get-selector address renderer))
+ (elpher-network-error "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)
- (message "filter")
(cancel-timer timer)
- (setq elpher-selector-string
- (concat elpher-selector-string string))))
+ (setq selector-string
+ (concat selector-string string))))
(set-process-sentinel proc
(lambda (_proc event)
- (message "Event: %s" event)
- (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)
- (condition-case the-error
- (progn
- (funcall renderer elpher-selector-string)
- (elpher-restore-pos))
- (error
- (message "sentinel %s" the-error)
- (elpher-network-error address the-error)))))))))
+ (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.
;; Gemini node retrieval
-(defvar elpher-gemini-response)
(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."
- (setq elpher-gemini-response "")
(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 the-error
(let* ((kill-buffer-query-functions nil)
(network-security-level 'medium)
(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)
(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 elpher-gemini-response
- (concat elpher-gemini-response string))))
+ (setq response-string
+ (concat response-string string))))
(set-process-sentinel proc
(lambda (proc event)
- (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 elpher-gemini-response)
- (not force-ipv4))
+ (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
- (cancel-timer timer)
- (elpher-get-gemini-response address renderer t))
- (t
- (funcall #'elpher-process-gemini-response
- renderer)
- (elpher-restore-pos))))))
+ (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 the-error
+ (elpher-network-error address the-error))))))
(error
(error "Error initiating connection to server")))))
(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 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)))))
- (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."