lisp/ob-screen.el

   1 ;;; ob-screen.el --- org-babel support for interactive terminal
   2
   3 ;; Copyright (C) 2009, 2010  Free Software Foundation
   4
   5 ;; Author: Benjamin Andresen
   6 ;; Keywords: literate programming, interactive shell
   7 ;; Homepage: http://orgmode.org
   8 ;; Version: 7.01
   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 of the License, or
  15 ;; (at your option) 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.  If not, see <http://www.gnu.org/licenses/>.
  24
  25 ;;; Commentary:
  26
  27 ;; Org-Babel support for interactive terminals. Mostly shell scripts.
  28 ;; Heavily inspired by 'eev' from Eduardo Ochs
  29 ;;
  30 ;; Adding :cmd and :terminal as header arguments
  31 ;; :terminal must support the -T (title) and -e (command) parameter
  32 ;;
  33 ;; You can test the default setup. (xterm + sh) with
  34 ;; M-x org-babel-screen-test RET
  35
  36 ;;; Code:
  37 (require 'ob)
  38 (require 'ob-ref)
  39
  40 (defvar org-babel-screen-location "screen"
  41   "The command location for screen.
  42 In case you want to use a different screen than one selected by your $PATH")
  43
  44 (defvar org-babel-default-header-args:screen
  45   '((:results . "silent") (:session . "default") (:cmd . "sh") (:terminal . "xterm"))
  46   "Default arguments to use when running screen source blocks.")
  47
  48 (defun org-babel-expand-body:screen (body params &optional processed-params)
  49   "Expand BODY according to PARAMS, return the expanded body." body)
  50
  51 (defun org-babel-execute:screen (body params)
  52   "Send a block of code via screen to a terminal using Babel.
  53 \"default\" session is be used when none is specified."
  54   (message "Sending source code block to interactive terminal session...")
  55   (save-window-excursion
  56     (let* ((processed-params (org-babel-process-params params))
  57            (session (nth 0 processed-params))
  58            (socket (org-babel-screen-session-socketname session)))
  59       (unless socket (org-babel-prep-session:screen session params))
  60       (org-babel-screen-session-execute-string
  61        session (org-babel-expand-body:screen body params)))))
  62
  63 (defun org-babel-prep-session:screen (session params)
  64   "Prepare SESSION according to the header arguments specified in PARAMS."
  65   (let* ((processed-params (org-babel-process-params params))
  66          (session (nth 0 processed-params))
  67          (vars (nth 1 processed-params))
  68          (socket (org-babel-screen-session-socketname session))
  69          (vars (org-babel-ref-variables params))
  70          (cmd (cdr (assoc :cmd params)))
  71          (terminal (cdr (assoc :terminal params)))
  72          (process-name (concat "org-babel: terminal (" session ")")))
  73     (apply 'start-process process-name "*Messages*"
  74            terminal `("-T" ,(concat "org-babel: " session) "-e" ,org-babel-screen-location
  75                            "-c" "/dev/null" "-mS" ,(concat "org-babel-session-" session)
  76                            ,cmd))
  77     ;; XXX: Is there a better way than the following?
  78     (while (not (org-babel-screen-session-socketname session))
  79       ;; wait until screen session is available before returning
  80       )))
  81
  82 ;; helper functions
  83
  84 (defun org-babel-screen-session-execute-string (session body)
  85   "If SESSION exists, send BODY to it."
  86   (let ((socket (org-babel-screen-session-socketname session)))
  87     (when socket
  88       (let ((tmpfile (org-babel-screen-session-write-temp-file session body)))
  89         (apply 'start-process (concat "org-babel: screen (" session ")") "*Messages*"
  90                org-babel-screen-location
  91                `("-S" ,socket "-X" "eval" "msgwait 0"
  92                       ,(concat "readreg z " tmpfile)
  93                       "paste z"))))))
  94
  95 (defun org-babel-screen-session-socketname (session)
  96   "Check if SESSION exists by parsing output of \"screen -ls\"."
  97   (let* ((screen-ls (shell-command-to-string "screen -ls"))
  98          (sockets (delq
  99                    nil
 100                    (mapcar
 101                     (lambda (x)
 102                       (when (string-match (rx (or "(Attached)" "(Detached)")) x)
 103                         x))
 104                     (split-string screen-ls "\n"))))
 105          (match-socket (car
 106                         (delq
 107                          nil
 108                          (mapcar
 109                           (lambda (x)
 110                             (when (string-match
 111                                    (concat "org-babel-session-" session) x)
 112                               x))
 113                           sockets)))))
 114     (when match-socket (car (split-string match-socket)))))
 115
 116 (defun org-babel-screen-session-write-temp-file (session body)
 117   "Save BODY in a temp file that is named after SESSION."
 118   (let ((tmpfile (concat "/tmp/screen.org-babel-session-" session)))
 119     (with-temp-file tmpfile
 120       (insert body)
 121
 122       ;; org-babel has superflous spaces
 123       (goto-char (point-min))
 124       (delete-matching-lines "^ +$"))
 125     tmpfile))
 126
 127 (defun org-babel-screen-test ()
 128   "Test if the default setup works.
 129 The terminal should shortly flicker."
 130   (interactive)
 131   (let* ((session "org-babel-testing")
 132          (random-string (format "%s" (random 99999)))
 133          (tmpfile "/tmp/org-babel-screen.test")
 134          (body (concat "echo '" random-string "' > " tmpfile "\nexit\n"))
 135          process tmp-string)
 136     (org-babel-execute:screen body org-babel-default-header-args:screen)
 137     ;; XXX: need to find a better way to do the following
 138     (while (not (file-readable-p tmpfile))
 139       ;; do something, otherwise this will be optimized away
 140       (format "org-babel-screen: File not readable yet."))
 141     (setq tmp-string (with-temp-buffer
 142                        (insert-file-contents-literally tmpfile)
 143                        (buffer-substring (point-min) (point-max))))
 144     (delete-file tmpfile)
 145     (message (concat "org-babel-screen: Setup "
 146                      (if (string-match random-string tmp-string)
 147                          "WORKS."
 148                          "DOESN'T work.")))))
 149
 150 (provide 'ob-screen)
 151
 152 ;; arch-tag: 908e5afe-89a0-4f27-b982-23f1f2e3bac9
 153
 154 ;;; ob-screen.el ends here