lisp/ob-eval.el

   1 ;;; ob-eval.el --- org-babel functions for external code evaluation
   2
   3 ;; Copyright (C) 2009-2012  Free Software Foundation, Inc.
   4
   5 ;; Author: Eric Schulte
   6 ;; Keywords: literate programming, reproducible research, comint
   7 ;; Homepage: http://orgmode.org
   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 3 of the License, or
  14 ;; (at your option) 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.  If not, see <http://www.gnu.org/licenses/>.
  23
  24 ;;; Commentary:
  25
  26 ;; These functions build existing Emacs support for executing external
  27 ;; shell commands.
  28
  29 ;;; Code:
  30 (eval-when-compile (require 'cl))
  31
  32 (defvar org-babel-error-buffer-name "*Org-Babel Error Output*")
  33
  34 (defun org-babel-eval-error-notify (exit-code stderr)
  35   "Open a buffer to display STDERR and a message with the value of EXIT-CODE."
  36   (let ((buf (get-buffer-create org-babel-error-buffer-name)))
  37     (with-current-buffer buf
  38       (goto-char (point-max))
  39       (save-excursion (insert stderr)))
  40     (display-buffer buf))
  41   (message "Babel evaluation exited with code %S" exit-code))
  42
  43 (defun org-babel-eval (cmd body)
  44   "Run CMD on BODY.
  45 If CMD succeeds then return its results, otherwise display
  46 STDERR with `org-babel-eval-error-notify'."
  47   (let ((err-buff (get-buffer-create " *Org-Babel Error*")) exit-code)
  48     (with-current-buffer err-buff (erase-buffer))
  49     (with-temp-buffer
  50       (insert body)
  51       (setq exit-code
  52             (org-babel-shell-command-on-region
  53              (point-min) (point-max) cmd t 'replace err-buff))
  54       (if (or (not (numberp exit-code)) (> exit-code 0))
  55           (progn
  56             (with-current-buffer err-buff
  57               (org-babel-eval-error-notify exit-code (buffer-string)))
  58             nil)
  59         (buffer-string)))))
  60
  61 (defun org-babel-eval-read-file (file)
  62   "Return the contents of FILE as a string."
  63   (with-temp-buffer (insert-file-contents file)
  64                     (buffer-string)))
  65
  66 (defun org-babel-shell-command-on-region (start end command
  67                                                 &optional output-buffer replace
  68                                                 error-buffer display-error-buffer)
  69   "Execute COMMAND in an inferior shell with region as input.
  70
  71 Fixes bugs in the emacs 23.1.1 version of `shell-command-on-region'
  72
  73 Normally display output (if any) in temp buffer `*Shell Command Output*';
  74 Prefix arg means replace the region with it.  Return the exit code of
  75 COMMAND.
  76
  77 To specify a coding system for converting non-ASCII characters in
  78 the input and output to the shell command, use
  79 \\[universal-coding-system-argument] before this command.  By
  80 default, the input (from the current buffer) is encoded in the
  81 same coding system that will be used to save the file,
  82 `buffer-file-coding-system'.  If the output is going to replace
  83 the region, then it is decoded from that same coding system.
  84
  85 The noninteractive arguments are START, END, COMMAND,
  86 OUTPUT-BUFFER, REPLACE, ERROR-BUFFER, and DISPLAY-ERROR-BUFFER.
  87 Noninteractive callers can specify coding systems by binding
  88 `coding-system-for-read' and `coding-system-for-write'.
  89
  90 If the command generates output, the output may be displayed
  91 in the echo area or in a buffer.
  92 If the output is short enough to display in the echo area
  93 \(determined by the variable `max-mini-window-height' if
  94 `resize-mini-windows' is non-nil), it is shown there.  Otherwise
  95 it is displayed in the buffer `*Shell Command Output*'.  The output
  96 is available in that buffer in both cases.
  97
  98 If there is output and an error, a message about the error
  99 appears at the end of the output.
 100
 101 If there is no output, or if output is inserted in the current buffer,
 102 then `*Shell Command Output*' is deleted.
 103
 104 If the optional fourth argument OUTPUT-BUFFER is non-nil,
 105 that says to put the output in some other buffer.
 106 If OUTPUT-BUFFER is a buffer or buffer name, put the output there.
 107 If OUTPUT-BUFFER is not a buffer and not nil,
 108 insert output in the current buffer.
 109 In either case, the output is inserted after point (leaving mark after it).
 110
 111 If REPLACE, the optional fifth argument, is non-nil, that means insert
 112 the output in place of text from START to END, putting point and mark
 113 around it.
 114
 115 If optional sixth argument ERROR-BUFFER is non-nil, it is a buffer
 116 or buffer name to which to direct the command's standard error output.
 117 If it is nil, error output is mingled with regular output.
 118 If DISPLAY-ERROR-BUFFER is non-nil, display the error buffer if there
 119 were any errors.  (This is always t, interactively.)
 120 In an interactive call, the variable `shell-command-default-error-buffer'
 121 specifies the value of ERROR-BUFFER."
 122   (interactive (let (string)
 123                  (unless (mark)
 124                    (error "The mark is not set now, so there is no region"))
 125                  ;; Do this before calling region-beginning
 126                  ;; and region-end, in case subprocess output
 127                  ;; relocates them while we are in the minibuffer.
 128                  (setq string (read-shell-command "Shell command on region: "))
 129                  ;; call-interactively recognizes region-beginning and
 130                  ;; region-end specially, leaving them in the history.
 131                  (list (region-beginning) (region-end)
 132                        string
 133                        current-prefix-arg
 134                        current-prefix-arg
 135                        shell-command-default-error-buffer
 136                        t)))
 137   (let ((error-file
 138          (if error-buffer
 139              (make-temp-file
 140               (expand-file-name "scor"
 141                                 (if (featurep 'xemacs)
 142                                     (temp-directory)
 143                                   temporary-file-directory)))
 144            nil))
 145         exit-status)
 146     (if (or replace
 147             (and output-buffer
 148                  (not (or (bufferp output-buffer) (stringp output-buffer)))))
 149         ;; Replace specified region with output from command.
 150         (let ((swap (and replace (< start end))))
 151           ;; Don't muck with mark unless REPLACE says we should.
 152           (goto-char start)
 153           (and replace (push-mark (point) 'nomsg))
 154           (setq exit-status
 155                 (call-process-region start end shell-file-name t
 156                                      (if error-file
 157                                          (list output-buffer error-file)
 158                                        t)
 159                                      nil shell-command-switch command))
 160           ;; It is rude to delete a buffer which the command is not using.
 161           ;; (let ((shell-buffer (get-buffer "*Shell Command Output*")))
 162           ;;   (and shell-buffer (not (eq shell-buffer (current-buffer)))
 163           ;;     (kill-buffer shell-buffer)))
 164           ;; Don't muck with mark unless REPLACE says we should.
 165           (and replace swap (exchange-point-and-mark)))
 166       ;; No prefix argument: put the output in a temp buffer,
 167       ;; replacing its entire contents.
 168       (let ((buffer (get-buffer-create
 169                      (or output-buffer "*Shell Command Output*"))))
 170         (unwind-protect
 171             (if (eq buffer (current-buffer))
 172                 ;; If the input is the same buffer as the output,
 173                 ;; delete everything but the specified region,
 174                 ;; then replace that region with the output.
 175                 (progn (setq buffer-read-only nil)
 176                        (delete-region (max start end) (point-max))
 177                        (delete-region (point-min) (min start end))
 178                        (setq exit-status
 179                              (call-process-region (point-min) (point-max)
 180                                                   shell-file-name t
 181                                                   (if error-file
 182                                                       (list t error-file)
 183                                                     t)
 184                                                   nil shell-command-switch
 185                                                   command)))
 186               ;; Clear the output buffer, then run the command with
 187               ;; output there.
 188               (let ((directory default-directory))
 189                 (with-current-buffer buffer
 190                   (setq buffer-read-only nil)
 191                   (if (not output-buffer)
 192                       (setq default-directory directory))
 193                   (erase-buffer)))
 194               (setq exit-status
 195                     (call-process-region start end shell-file-name nil
 196                                          (if error-file
 197                                              (list buffer error-file)
 198                                            buffer)
 199                                          nil shell-command-switch command)))
 200           ;; Report the output.
 201           (with-current-buffer buffer
 202             (setq mode-line-process
 203                   (cond ((null exit-status)
 204                          " - Error")
 205                         ((stringp exit-status)
 206                          (format " - Signal [%s]" exit-status))
 207                         ((not (equal 0 exit-status))
 208                          (format " - Exit [%d]" exit-status)))))
 209           (if (with-current-buffer buffer (> (point-max) (point-min)))
 210               ;; There's some output, display it
 211               (display-message-or-buffer buffer)
 212             ;; No output; error?
 213             (let ((output
 214                    (if (and error-file
 215                             (< 0 (nth 7 (file-attributes error-file))))
 216                        "some error output"
 217                      "no output")))
 218               (cond ((null exit-status)
 219                      (message "(Shell command failed with error)"))
 220                     ((equal 0 exit-status)
 221                      (message "(Shell command succeeded with %s)"
 222                               output))
 223                     ((stringp exit-status)
 224                      (message "(Shell command killed by signal %s)"
 225                               exit-status))
 226                     (t
 227                      (message "(Shell command failed with code %d and %s)"
 228                               exit-status output))))
 229             ;; Don't kill: there might be useful info in the undo-log.
 230             ;; (kill-buffer buffer)
 231             ))))
 232
 233     (when (and error-file (file-exists-p error-file))
 234       (if (< 0 (nth 7 (file-attributes error-file)))
 235           (with-current-buffer (get-buffer-create error-buffer)
 236             (let ((pos-from-end (- (point-max) (point))))
 237               (or (bobp)
 238                   (insert "\f\n"))
 239               ;; Do no formatting while reading error file,
 240               ;; because that can run a shell command, and we
 241               ;; don't want that to cause an infinite recursion.
 242               (format-insert-file error-file nil)
 243               ;; Put point after the inserted errors.
 244               (goto-char (- (point-max) pos-from-end)))
 245             (and display-error-buffer
 246                  (display-buffer (current-buffer)))))
 247       (delete-file error-file))
 248     exit-status))
 249
 250 (defun org-babel-eval-wipe-error-buffer ()
 251   "Delete the contents of the Org code block error buffer.
 252 This buffer is named by `org-babel-error-buffer-name'."
 253   (when (get-buffer org-babel-error-buffer-name)
 254     (with-current-buffer org-babel-error-buffer-name
 255       (delete-region (point-min) (point-max)))))
 256
 257 (provide 'ob-eval)
 258
 259
 260
 261 ;;; ob-eval.el ends here