Updated package header.

[elpher.git] / elpher.el

diff --git a/elpher.el b/elpher.el
index c0734ca..8e2e48e 100644 (file)
--- a/elpher.el
+++ b/elpher.el
@@ -4,7 +4,7 @@
 
 ;; Author: Tim Vaughan <tgvaughan@gmail.com>
 ;; Created: 11 April 2019
-;; Version: 1.4.2
+;; Version: 1.4.3
 ;; Keywords: comm gopher
 ;; Homepage: https://github.com/tgvaughan/elpher
 ;; Package-Requires: ((emacs "25"))
@@ -30,20 +30,19 @@
 ;; for GNU Emacs.  It supports:
 
 ;; - an intuitive keyboard and mouse-driven interface,
+;; - followable web and gopher links in plain text,
 ;; - caching of visited sites (both content and cursor position),
 ;; - pleasant and configurable colouring of Gopher directories,
 ;; - direct visualisation of image files,
 ;; - (m)enu key support, similar to Emacs' info browser,
-;; - clickable web and gopher links in plain text,
 ;; - a simple bookmark management system,
-;; - support for TLS gopherholes.
+;; - support for TLS.
 
 ;; To launch Elpher, simply use 'M-x elpher'.  This will open a start
 ;; page containing information on key bindings and suggested starting
 ;; points for your gopher exploration.
 
-;; Faces, caching and other options can be configured via
-;; the Elpher customization group in Applications.
+;; Further instructions can be found in the Elpher info manual.
 
 ;; Elpher is under active development, and any suggestions for
 ;; improvements are welcome!
@@ -58,7 +57,7 @@
 ;;; Global constants
 ;;
 
-(defconst elpher-version "1.4.2"
+(defconst elpher-version "1.4.3"
   "Current version of elpher.")
 
 (defconst elpher-margin-width 6
@@ -195,6 +194,13 @@ Otherwise, use the system browser via the BROWSE-URL function."
   "If non-nil, display current node 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))
+
+
 ;;; Model
 ;;
 
@@ -466,9 +472,14 @@ The contents of the record are dictated by DISPLAY-STRING and ADDRESS."
 
 (defvar elpher-selector-string)
 
-(defun elpher-get-selector (address after)
+(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’."
+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)
@@ -483,6 +494,7 @@ The result is stored as a string in the variable ‘elpher-selector-string’."
                                        (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
@@ -493,17 +505,21 @@ The result is stored as a string in the variable ‘elpher-selector-string’."
     (error
      (if (and (consp the-error)
               (eq (car the-error) 'gnutls-error)
-              (not (elpher-address-use-tls-p address)))
+              (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 "Could not establish TLS connection.  Disengaging TLS mode.")
+           (message "Disengaging TLS mode.")
            (setq elpher-use-tls nil)
            (elpher-get-selector address after))
        (elpher-process-cleanup)
-       (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."))))))
+       (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
 
@@ -707,13 +723,17 @@ calls, as is necessary if the match is performed by `string-match'."
                                        "gopher.file"))))
       (message "Downloading...")
       (setq elpher-download-filename filename)
-      (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)))))))))
+      (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)
+        (error
+         (error "Error downloading %s" elpher-download-filename))))))
 
 ;; URL retrieval