lisp/vmsproc.el

   1 ;;; vmsproc.el --- run asynchronous VMS subprocesses under Emacs
   2
   3 ;; Copyright (C) 1986, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
   4
   5 ;; Author: Mukesh Prasad
   6 ;; Maintainer: FSF
   7 ;; Keywords: vms
   8
   9 ;; This file is part of GNU Emacs.
  10
  11 ;; GNU Emacs is free software; you can redistribute it and/or modify
  12 ;; it under the terms of the GNU General Public License as published by
  13 ;; the Free Software Foundation; either version 2, or (at your option)
  14 ;; any later version.
  15
  16 ;; GNU Emacs is distributed in the hope that it will be useful,
  17 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 ;; GNU General Public License for more details.
  20
  21 ;; You should have received a copy of the GNU General Public License
  22 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  23 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  24 ;; Boston, MA 02110-1301, USA.
  25
  26 ;;; Commentary:
  27
  28 ;;; Code:
  29
  30 (defvar display-subprocess-window nil
  31   "If non-nil, the subprocess window is displayed whenever input is received.")
  32
  33 (defvar command-prefix-string "$ "
  34   "String to insert to distinguish commands entered by user.")
  35
  36 (defvar subprocess-running nil)
  37 (defvar subprocess-buf nil)
  38
  39 (defvar command-mode-map
  40   (let ((map (make-sparse-keymap)))
  41     (define-key map "\C-m" 'command-send-input)
  42     (define-key map "\C-u" 'command-kill-line)
  43     map))
  44
  45 (defun subprocess-input (name str)
  46   "Handles input from a subprocess.  Called by Emacs."
  47   (if display-subprocess-window
  48       (display-buffer subprocess-buf))
  49   (with-current-buffer subprocess-buf
  50     (goto-char (point-max))
  51     (insert str ?\n)))
  52
  53 (defun subprocess-exit (name)
  54   "Called by Emacs upon subprocess exit."
  55   (setq subprocess-running nil))
  56
  57 (defun start-subprocess ()
  58   "Spawns an asynchronous subprocess with output redirected to
  59 the buffer *COMMAND*.  Within this buffer, use C-m to send
  60 the last line to the subprocess or to bring another line to
  61 the end."
  62   (if subprocess-running
  63       (return t))
  64   (setq subprocess-buf (get-buffer-create "*COMMAND*"))
  65   (with-current-buffer subprocess-buf
  66     (use-local-map command-mode-map))
  67   (setq subprocess-running (spawn-subprocess 1 'subprocess-input
  68                                              'subprocess-exit))
  69   ;; Initialize subprocess so it doesn't panic and die upon
  70   ;; encountering the first error.
  71   (and subprocess-running
  72        (send-command-to-subprocess 1 "ON SEVERE_ERROR THEN CONTINUE")))
  73
  74 (defun subprocess-command-to-buffer (command buffer)
  75   "Execute COMMAND and redirect output into BUFFER."
  76   (let (cmd args)
  77     (setq cmd (substring command 0 (string-match " " command)))
  78     (setq args (substring command (string-match " " command)))
  79     (call-process cmd nil buffer nil "*dcl*" args)))
  80   ;; BUGS: only the output up to the end of the first image activation is trapped.
  81   ;; (if (not subprocess-running)
  82   ;;     (start-subprocess))
  83   ;; (with-current-buffer buffer
  84   ;;   (let ((output-filename (concat "SYS$SCRATCH:OUTPUT-FOR-"
  85   ;;                               (getenv "USER") ".LISTING")))
  86   ;;     (while (file-exists-p output-filename)
  87   ;;       (delete-file output-filename))
  88   ;;     (define-logical-name "SYS$OUTPUT" (concat output-filename "-NEW"))
  89   ;;     (send-command-to-subprocess 1 command)
  90   ;;     (send-command-to-subprocess 1 (concat
  91   ;;                                 "RENAME " output-filename
  92   ;;                                 "-NEW " output-filename))
  93   ;;     (while (not (file-exists-p output-filename))
  94   ;;       (sleep-for 1))
  95   ;;     (define-logical-name "SYS$OUTPUT" nil)
  96   ;;     (insert-file output-filename)
  97   ;;     (delete-file output-filename))))
  98
  99 (defun subprocess-command ()
 100   "Starts asynchronous subprocess if not running and switches to its window."
 101   (interactive)
 102   (if (not subprocess-running)
 103       (start-subprocess))
 104   (and subprocess-running
 105        (progn (pop-to-buffer subprocess-buf) (goto-char (point-max)))))
 106
 107 (defun command-send-input ()
 108   "If at last line of buffer, sends the current line to
 109 the spawned subprocess.  Otherwise brings back current
 110 line to the last line for resubmission."
 111   (interactive)
 112   (beginning-of-line)
 113   (let ((current-line (buffer-substring (point) (line-end-position))))
 114     (if (eobp)
 115         (progn
 116           (if (not subprocess-running)
 117               (start-subprocess))
 118           (if subprocess-running
 119               (progn
 120                 (beginning-of-line)
 121                 (send-command-to-subprocess 1 current-line)
 122                 (if command-prefix-string
 123                     (progn (beginning-of-line) (insert command-prefix-string)))
 124                 (next-line 1))))
 125       ;; else -- if not at last line in buffer
 126       (goto-char (point-max))
 127       (backward-char)
 128       (next-line 1)
 129       (insert
 130        (if (compare-strings command-prefix-string nil nil
 131                             current-line 0 (length command-prefix-string))
 132            (substring current-line (length command-prefix-string))
 133          current-line)))))
 134
 135 (defun command-kill-line ()
 136   "Kills the current line.  Used in command mode."
 137   (interactive)
 138   (beginning-of-line)
 139   (kill-line))
 140
 141 (define-key esc-map "$" 'subprocess-command)
 142
 143 ;; arch-tag: 600b2512-f903-4887-bcd2-e76b306f5b66
 144 ;;; vmsproc.el ends here