-(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."
- (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."))
- (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 "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
+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)))))
+ (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