;;; rlogin.el --- remote login interface

;; Maintainer: Noah Friedman <friedman@prep.ai.mit.edu>
;; Keywords: unix

;;; Copyright (C) 1992 Free Software Foundation, Inc.
;;;
;;; This program is free software; you can redistribute it and/or modify
;;; it under the terms of the GNU General Public License as published by
;;; the Free Software Foundation; either version 2, or (at your option)
;;; any later version.
;;;
;;; This program is distributed in the hope that it will be useful,
;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;;; GNU General Public License for more details.
;;;
;;; You should have received a copy of the GNU General Public License
;;; along with this program; if not, you can either send email to this
;;; program's author (see below) or write to:
;;;
;;;              The Free Software Foundation, Inc.
;;;              675 Massachusetts Avenue.
;;;              Cambridge, MA 02139, USA. 
;;;

;;; Todo: add directory tracking using ange-ftp style patchnames for the cwd.

;;; Code:

(require 'comint)

(defvar rlogin-program "rlogin"
  "*Name of program to invoke rlogin")

(defvar rlogin-mode-hook nil
  "*Hooks to run after setting current buffer to rlogin-mode.")

;; Initialize rlogin mode map.
(defvar rlogin-mode-map '())
(cond ((not rlogin-mode-map)
       (setq rlogin-mode-map (full-copy-sparse-keymap comint-mode-map))
       ;(define-key rlogin-mode-map "\M-\t" 'comint-dynamic-complete)
       ;(define-key rlogin-mode-map "\M-?"  'comint-dynamic-list-completions)
       (define-key rlogin-mode-map "\C-c\C-c" 'rlogin-send-Ctrl-C)
       (define-key rlogin-mode-map "\C-c\C-z" 'rlogin-send-Ctrl-Z)
       (define-key rlogin-mode-map "\C-c\C-\\" 'rlogin-send-Ctrl-backslash)
       (define-key rlogin-mode-map "\C-d" 'rlogin-delchar-or-send-Ctrl-D)))

(defun rlogin (host)
  (interactive "sOpen rlogin connection to host: ")
  (let* ((buffer-name (concat "rlogin-" host))
         (*buffer-name* (concat "*" buffer-name "*")))
    (cond ((not (comint-check-proc *buffer-name*))
           (let* ((xargs-name (intern-soft "explicit-rlogin-args"))
                  (xargs (and xargs-name (boundp xargs-name) (symbol-value xargs-name)))
                  (process-connection-type nil)
                  proc)
             (if xargs
                 (setq xargs (append xargs host))
               (setq xargs (list host)))
             (set-buffer (apply 'make-comint buffer-name rlogin-program nil xargs))
             (setq proc (get-process buffer-name))
             (set-process-filter proc 'rlogin-filter)
             (rlogin-mode))))
    (switch-to-buffer *buffer-name*)))

(defun rlogin-mode ()
  (interactive)
  (comint-mode)
  (setq comint-prompt-regexp shell-prompt-pattern)
  (setq major-mode 'rlogin-mode)
  (setq mode-name "Rlogin")
  (use-local-map rlogin-mode-map)
  (run-hooks 'rlogin-mode-hook))

(defun rlogin-filter (proc string)
  (let ((process-buffer (process-buffer proc))
        (at-eobp (eobp)))
    (save-excursion
      (set-buffer process-buffer)
      (goto-char (point-max))
      (let ((now (point))
            process-mark)
        (insert string)
        (subst-char-in-region now (point) ?\C-m ?\ )
        (subst-char-in-region now (point) ?\M-r ?\ )
        (setq process-mark (process-mark proc))
        (and process-mark
            (set-marker process-mark (point)))))
    (and at-eobp
         (eq process-buffer (current-buffer))
         (goto-char (point-max)))))

(defun rlogin-send-Ctrl-C ()
  (interactive)
  (send-string nil "\C-c"))

(defun rlogin-send-Ctrl-Z ()
  (interactive)
  (send-string nil "\C-z"))

(defun rlogin-send-Ctrl-backslash ()
  (interactive)
  (send-string nil "\C-\\"))

(defun rlogin-delchar-or-send-Ctrl-D (arg)
  "Delete ARG characters forward, or send a C-d to process if at end of
buffer."  
  (interactive "p") 
  (if (eobp)
      (send-string nil "\C-d")
    (delete-char arg)))

;;; rlogin.el ends here