lisp/vmsproc.el

   1 ;;; vmsproc.el --- run asynchronous VMS subprocesses under Emacs
   2
   3 ;; Copyright (C) 1986, 2001, 2002, 2003, 2004, 2005,
   4 ;;   2006, 2007 Free Software Foundation, Inc.
   5
   6 ;; Author: Mukesh Prasad
   7 ;; Maintainer: FSF
   8 ;; Keywords: vms
   9
  10 ;; This file is part of GNU Emacs.
  11
  12 ;; GNU Emacs is free software; you can redistribute it and/or modify
  13 ;; it under the terms of the GNU General Public License as published by
  14 ;; the Free Software Foundation; either version 3, or (at your option)
  15 ;; any later version.
  16
  17 ;; GNU Emacs is distributed in the hope that it will be useful,
  18 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 ;; GNU General Public License for more details.
  21
  22 ;; You should have received a copy of the GNU General Public License
  23 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  24 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  25 ;; Boston, MA 02110-1301, USA.
  26
  27 ;;; Commentary:
  28
  29 ;;; Code:
  30
  31 (defvar display-subprocess-window nil
  32   "If non-nil, the subprocess window is displayed whenever input is received.")
  33
  34 (defvar command-prefix-string "$ "
  35   "String to insert to distinguish commands entered by user.")
  36
  37 (defvar subprocess-running nil)
  38 (defvar subprocess-buf nil)
  39
  40 (defvar command-mode-map
  41   (let ((map (make-sparse-keymap)))
  42     (define-key map "\C-m" 'command-send-input)
  43     (define-key map "\C-u" 'command-kill-line)
  44     map))
  45
  46 (defun subprocess-input (name str)
  47   "Handle input from a subprocess.  Called by Emacs."
  48   (if display-subprocess-window
  49       (display-buffer subprocess-buf))
  50   (with-current-buffer subprocess-buf
  51     (goto-char (point-max))
  52     (insert str ?\n)))
  53
  54 (defun subprocess-exit (name)
  55   "Called by Emacs upon subprocess exit."
  56   (setq subprocess-running nil))
  57
  58 (defun start-subprocess ()
  59   "Spawn an asynchronous subprocess with output redirected to
  60 the buffer *COMMAND*.  Within this buffer, use C-m to send
  61 the last line to the subprocess or to bring another line to
  62 the end."
  63   (if subprocess-running
  64       (return t))
  65   (setq subprocess-buf (get-buffer-create "*COMMAND*"))
  66   (with-current-buffer subprocess-buf
  67     (use-local-map command-mode-map))
  68   (setq subprocess-running (spawn-subprocess 1 'subprocess-input
  69                                              'subprocess-exit))
  70   ;; Initialize subprocess so it doesn't panic and die upon
  71   ;; encountering the first error.
  72   (and subprocess-running
  73        (send-command-to-subprocess 1 "ON SEVERE_ERROR THEN CONTINUE")))
  74
  75 (defun subprocess-command-to-buffer (command buffer)
  76   "Execute COMMAND and redirect output into BUFFER."
  77   (let (cmd args)
  78     (setq cmd (substring command 0 (string-match " " command)))
  79     (setq args (substring command (string-match " " command)))
  80     (call-process cmd nil buffer nil "*dcl*" args)))
  81   ;; BUGS: only the output up to the end of the first image activation is trapped.
  82   ;; (if (not subprocess-running)
  83   ;;     (start-subprocess))
  84   ;; (with-current-buffer buffer
  85   ;;   (let ((output-filename (concat "SYS$SCRATCH:OUTPUT-FOR-"
  86   ;;                               (getenv "USER") ".LISTING")))
  87   ;;     (while (file-exists-p output-filename)
  88   ;;       (delete-file output-filename))
  89   ;;     (define-logical-name "SYS$OUTPUT" (concat output-filename "-NEW"))
  90   ;;     (send-command-to-subprocess 1 command)
  91   ;;     (send-command-to-subprocess 1 (concat
  92   ;;                                 "RENAME " output-filename
  93   ;;                                 "-NEW " output-filename))
  94   ;;     (while (not (file-exists-p output-filename))
  95   ;;       (sleep-for 1))
  96   ;;     (define-logical-name "SYS$OUTPUT" nil)
  97   ;;     (insert-file output-filename)
  98   ;;     (delete-file output-filename))))
  99
 100 (defun subprocess-command ()
 101   "Start asynchronous subprocess if not running and switch to its window."
 102   (interactive)
 103   (if (not subprocess-running)
 104       (start-subprocess))
 105   (and subprocess-running
 106        (progn (pop-to-buffer subprocess-buf) (goto-char (point-max)))))
 107
 108 (defun command-send-input ()
 109   "If at last line of buffer, send the current line to
 110 the spawned subprocess.  Otherwise bring back current
 111 line to the last line for resubmission."
 112   (interactive)
 113   (beginning-of-line)
 114   (let ((current-line (buffer-substring (point) (line-end-position))))
 115     (if (eobp)
 116         (progn
 117           (if (not subprocess-running)
 118               (start-subprocess))
 119           (if subprocess-running
 120               (progn
 121                 (beginning-of-line)
 122                 (send-command-to-subprocess 1 current-line)
 123                 (if command-prefix-string
 124                     (progn (beginning-of-line) (insert command-prefix-string)))
 125                 (forward-line 1))))
 126       ;; else -- if not at last line in buffer
 127       (goto-char (point-max))
 128       (backward-char)
 129       (forward-line 1)
 130       (insert
 131        (if (compare-strings command-prefix-string nil nil
 132                             current-line 0 (length command-prefix-string))
 133            (substring current-line (length command-prefix-string))
 134          current-line)))))
 135
 136 (defun command-kill-line ()
 137   "Kill the current line.  Used in command mode."
 138   (interactive)
 139   (beginning-of-line)
 140   (kill-line))
 141
 142 (define-key esc-map "$" 'subprocess-command)
 143
 144 (provide 'vmsproc)
 145
 146 ;; arch-tag: 600b2512-f903-4887-bcd2-e76b306f5b66
 147 ;;; vmsproc.el ends here