lisp/vmsproc.el

   1 ;; -*- no-byte-compile: t -*-
   2 ;;; vmsproc.el --- run asynchronous VMS subprocesses under Emacs
   3
   4 ;; Copyright (C) 1986, 2001, 2002, 2003, 2004, 2005,
   5 ;;   2006, 2007, 2008 Free Software Foundation, Inc.
   6
   7 ;; Author: Mukesh Prasad
   8 ;; Maintainer: FSF
   9 ;; Keywords: vms
  10
  11 ;; This file is part of GNU Emacs.
  12
  13 ;; GNU Emacs is free software; you can redistribute it and/or modify
  14 ;; it under the terms of the GNU General Public License as published by
  15 ;; the Free Software Foundation; either version 3, or (at your option)
  16 ;; any later version.
  17
  18 ;; GNU Emacs is distributed in the hope that it will be useful,
  19 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  20 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21 ;; GNU General Public License for more details.
  22
  23 ;; You should have received a copy of the GNU General Public License
  24 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  25 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  26 ;; Boston, MA 02110-1301, USA.
  27
  28 ;;; Commentary:
  29
  30 ;;; Code:
  31
  32 (defvar display-subprocess-window nil
  33   "If non-nil, the subprocess window is displayed whenever input is received.")
  34
  35 (defvar command-prefix-string "$ "
  36   "String to insert to distinguish commands entered by user.")
  37
  38 (defvar subprocess-running nil)
  39 (defvar subprocess-buf nil)
  40
  41 (defvar command-mode-map
  42   (let ((map (make-sparse-keymap)))
  43     (define-key map "\C-m" 'command-send-input)
  44     (define-key map "\C-u" 'command-kill-line)
  45     map))
  46
  47 (defun subprocess-input (name str)
  48   "Handle input from a subprocess.  Called by Emacs."
  49   (if display-subprocess-window
  50       (display-buffer subprocess-buf))
  51   (with-current-buffer subprocess-buf
  52     (goto-char (point-max))
  53     (insert str ?\n)))
  54
  55 (defun subprocess-exit (name)
  56   "Called by Emacs upon subprocess exit."
  57   (setq subprocess-running nil))
  58
  59 (defun start-subprocess ()
  60   "Spawn an asynchronous subprocess with output redirected to
  61 the buffer *COMMAND*.  Within this buffer, use C-m to send
  62 the last line to the subprocess or to bring another line to
  63 the end."
  64   (if subprocess-running
  65       (return t))
  66   (setq subprocess-buf (get-buffer-create "*COMMAND*"))
  67   (with-current-buffer subprocess-buf
  68     (use-local-map command-mode-map))
  69   (setq subprocess-running (spawn-subprocess 1 'subprocess-input
  70                                              'subprocess-exit))
  71   ;; Initialize subprocess so it doesn't panic and die upon
  72   ;; encountering the first error.
  73   (and subprocess-running
  74        (send-command-to-subprocess 1 "ON SEVERE_ERROR THEN CONTINUE")))
  75
  76 (defun subprocess-command-to-buffer (command buffer)
  77   "Execute COMMAND and redirect output into BUFFER."
  78   (let (cmd args)
  79     (setq cmd (substring command 0 (string-match " " command)))
  80     (setq args (substring command (string-match " " command)))
  81     (call-process cmd nil buffer nil "*dcl*" args)))
  82   ;; BUGS: only the output up to the end of the first image activation is trapped.
  83   ;; (if (not subprocess-running)
  84   ;;     (start-subprocess))
  85   ;; (with-current-buffer buffer
  86   ;;   (let ((output-filename (concat "SYS$SCRATCH:OUTPUT-FOR-"
  87   ;;                               (getenv "USER") ".LISTING")))
  88   ;;     (while (file-exists-p output-filename)
  89   ;;       (delete-file output-filename))
  90   ;;     (define-logical-name "SYS$OUTPUT" (concat output-filename "-NEW"))
  91   ;;     (send-command-to-subprocess 1 command)
  92   ;;     (send-command-to-subprocess 1 (concat
  93   ;;                                 "RENAME " output-filename
  94   ;;                                 "-NEW " output-filename))
  95   ;;     (while (not (file-exists-p output-filename))
  96   ;;       (sleep-for 1))
  97   ;;     (define-logical-name "SYS$OUTPUT" nil)
  98   ;;     (insert-file output-filename)
  99   ;;     (delete-file output-filename))))
 100
 101 (defun subprocess-command ()
 102   "Start asynchronous subprocess if not running and switch to its window."
 103   (interactive)
 104   (if (not subprocess-running)
 105       (start-subprocess))
 106   (and subprocess-running
 107        (progn (pop-to-buffer subprocess-buf) (goto-char (point-max)))))
 108
 109 (defun command-send-input ()
 110   "If at last line of buffer, send the current line to
 111 the spawned subprocess.  Otherwise bring back current
 112 line to the last line for resubmission."
 113   (interactive)
 114   (beginning-of-line)
 115   (let ((current-line (buffer-substring (point) (line-end-position))))
 116     (if (eobp)
 117         (progn
 118           (if (not subprocess-running)
 119               (start-subprocess))
 120           (if subprocess-running
 121               (progn
 122                 (beginning-of-line)
 123                 (send-command-to-subprocess 1 current-line)
 124                 (if command-prefix-string
 125                     (progn (beginning-of-line) (insert command-prefix-string)))
 126                 (forward-line 1))))
 127       ;; else -- if not at last line in buffer
 128       (goto-char (point-max))
 129       (backward-char)
 130       (forward-line 1)
 131       (insert
 132        (if (compare-strings command-prefix-string nil nil
 133                             current-line 0 (length command-prefix-string))
 134            (substring current-line (length command-prefix-string))
 135          current-line)))))
 136
 137 (defun command-kill-line ()
 138   "Kill the current line.  Used in command mode."
 139   (interactive)
 140   (beginning-of-line)
 141   (kill-line))
 142
 143 (define-key esc-map "$" 'subprocess-command)
 144
 145 (provide 'vmsproc)
 146
 147 ;; arch-tag: 600b2512-f903-4887-bcd2-e76b306f5b66
 148 ;;; vmsproc.el ends here