lisp/progmodes/executable.el

   1 ;;; executable.el --- base functionality for executable interpreter scripts -*- byte-compile-dynamic: t -*-
   2
   3 ;; Copyright (C) 1994-1996, 2000-2017 Free Software Foundation, Inc.
   4
   5 ;; Author: Daniel Pfeiffer <occitan@esperanto.org>
   6 ;; Keywords: languages, unix
   7
   8 ;; This file is part of GNU Emacs.
   9
  10 ;; GNU Emacs is free software: you can redistribute it and/or modify
  11 ;; it under the terms of the GNU General Public License as published by
  12 ;; the Free Software Foundation, either version 3 of the License, or
  13 ;; (at your option) any later version.
  14
  15 ;; GNU Emacs is distributed in the hope that it will be useful,
  16 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 ;; GNU General Public License for more details.
  19
  20 ;; You should have received a copy of the GNU General Public License
  21 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  22
  23 ;;; Commentary:
  24
  25 ;; executable.el is used by certain major modes to insert a suitable
  26 ;; #! line at the beginning of the file, if the file does not already
  27 ;; have one.
  28
  29 ;; Unless it has a magic number, a Unix file with executable mode is passed to
  30 ;; a new instance of the running shell (or to a Bourne shell if a csh is
  31 ;; running and the file starts with `:').  Only a shell can start such a file,
  32 ;; exec() cannot, which is why it is important to have a magic number in every
  33 ;; executable script.  Such a magic number is made up by the characters `#!'
  34 ;; the filename of an interpreter (in COFF, ELF or somesuch format) and one
  35 ;; optional argument.
  36
  37 ;; This library is for certain major modes like sh-, awk-, perl-, tcl- or
  38 ;; makefile-mode to insert or update a suitable #! line at the beginning of
  39 ;; the file, if the file does not already have one and the file is not a
  40 ;; default file of that interpreter (like .profile or makefile).  It also
  41 ;; makes the file executable if it wasn't, as soon as it's saved.
  42
  43 ;; It also allows debugging scripts, with an adaptation of compile, as far
  44 ;; as interpreters give out meaningful error messages.
  45
  46 ;; Modes that use this should nconc `executable-map' to the end of their own
  47 ;; keymap and `executable-font-lock-keywords' to the end of their own font
  48 ;; lock keywords.  Their mode-setting commands should call
  49 ;; `executable-set-magic'.
  50
  51 ;;; Code:
  52
  53 (defgroup executable nil
  54   "Base functionality for executable interpreter scripts."
  55   :group 'processes)
  56
  57 ;; This used to default to `other', but that doesn't seem to have any
  58 ;; significance.  fx 2000-02-11.
  59 (defcustom executable-insert t          ; 'other
  60   "Non-nil means offer to add a magic number to a file.
  61 This takes effect when you switch to certain major modes,
  62 including Shell-script mode (`sh-mode').
  63 When you type \\[executable-set-magic], it always offers to add or
  64 update the magic number."
  65 ;;;   :type '(choice (const :tag "off" nil)
  66 ;;;              (const :tag "on" t)
  67 ;;;              symbol)
  68   :type 'boolean
  69   :group 'executable)
  70
  71
  72 (defcustom executable-query 'function
  73   "If non-nil, ask user before changing an existing magic number.
  74 When this is `function', only ask when called non-interactively."
  75   :type '(choice (const :tag "Don't Ask" nil)
  76                  (const :tag "Ask when non-interactive" function)
  77                  (other :tag "Ask" t))
  78   :group 'executable)
  79
  80
  81 (defcustom executable-magicless-file-regexp "/[Mm]akefile$\\|/\\.\\(z?profile\\|bash_profile\\|z?login\\|bash_login\\|z?logout\\|bash_logout\\|.+shrc\\|esrc\\|rcrc\\|[kz]shenv\\)$"
  82   "On files with this kind of name no magic is inserted or changed."
  83   :type 'regexp
  84   :group 'executable)
  85
  86
  87 (defcustom executable-prefix "#!"
  88   "Interpreter magic number prefix inserted when there was no magic number."
  89   :version "24.3"                       ; "#! " -> "#!"
  90   :type 'string
  91   :group 'executable)
  92
  93
  94 (defcustom executable-chmod 73
  95   "After saving, if the file is not executable, set this mode.
  96 This mode passed to `set-file-modes' is taken absolutely when negative, or
  97 relative to the files existing modes.  Do nothing if this is nil.
  98 Typical values are 73 (+x) or -493 (rwxr-xr-x)."
  99   :type '(choice integer
 100                  (const nil))
 101   :group 'executable)
 102
 103
 104 (defvar executable-command nil)
 105
 106 (defcustom executable-self-display "tail"
 107   "Command you use with argument `-n+2' to make text files self-display.
 108 Note that the like of `more' doesn't work too well under Emacs \\[shell]."
 109   :type 'string
 110   :group 'executable)
 111
 112 (make-obsolete-variable 'executable-self-display nil "25.1" 'set)
 113
 114
 115 (defvar executable-font-lock-keywords
 116   '(("\\`#!.*/\\([^ \t\n]+\\)" 1 font-lock-keyword-face t))
 117   "Rules for highlighting executable scripts' magic number.
 118 This can be included in `font-lock-keywords' by modes that call `executable'.")
 119
 120
 121 (defvar executable-error-regexp-alist
 122   '(;; /bin/xyz: syntax error at line 14: `(' unexpected
 123     ;; /bin/xyz[5]: syntax error at line 8 : ``' unmatched
 124     ("^\\(.*[^[/]\\)\\(\\[[0-9]+\\]\\)?: .* error .* line \\([0-9]+\\)" 1 3)
 125     ;; /bin/xyz[27]: ehco:  not found
 126     ("^\\(.*[^/]\\)\\[\\([0-9]+\\)\\]: .*: " 1 2)
 127     ;; /bin/xyz: syntax error near unexpected token `)'
 128     ;; /bin/xyz: /bin/xyz: line 2: `)'
 129     ("^\\(.*[^/]\\): [^0-9\n]+\n\\1: \\1: line \\([0-9]+\\):" 1 2)
 130     ;; /usr/bin/awk: syntax error at line 5 of file /bin/xyz
 131     (" error .* line \\([0-9]+\\) of file \\(.+\\)$" 2 1)
 132     ;; /usr/bin/awk: calling undefined function toto
 133     ;;  input record number 3, file awktestdata
 134     ;;  source line 4 of file /bin/xyz
 135     ("^[^ ].+\n\\( .+\n\\)* line \\([0-9]+\\) of file \\(.+\\)$" 3 2)
 136     ;; makefile:1: *** target pattern contains no `%'.  Stop.
 137     ("^\\(.+\\):\\([0-9]+\\): " 1 2))
 138   "Alist of regexps used to match script errors.
 139 See `compilation-error-regexp-alist'.")
 140
 141 ;; The C function openp slightly modified would do the trick fine
 142 (defvaralias 'executable-binary-suffixes 'exec-suffixes)
 143
 144 ;;;###autoload
 145 (defun executable-command-find-posix-p (&optional program)
 146   "Check if PROGRAM handles arguments Posix-style.
 147 If PROGRAM is non-nil, use that instead of \"find\"."
 148   ;;  Pick file to search from location we know
 149   (let* ((dir (file-truename data-directory))
 150          (file (car (directory-files dir nil "^[^.]"))))
 151     (with-temp-buffer
 152       (call-process (or program "find")
 153                     nil
 154                     (current-buffer)
 155                     nil
 156                     dir
 157                     "-name"
 158                     file
 159                     "-maxdepth"
 160                     "1")
 161         (goto-char (point-min))
 162         (if (search-forward file nil t)
 163             t))))
 164
 165 (defun executable-chmod ()
 166   "This gets called after saving a file to assure that it be executable.
 167 You can set the absolute or relative mode in variable `executable-chmod' for
 168 non-executable files."
 169   (and executable-chmod
 170        buffer-file-name
 171        (or (file-executable-p buffer-file-name)
 172            (set-file-modes buffer-file-name
 173                            (if (< executable-chmod 0)
 174                                (- executable-chmod)
 175                              (logior executable-chmod
 176                                      (file-modes buffer-file-name)))))))
 177
 178
 179 (defvar compilation-error-regexp-alist) ; from compile.el
 180
 181 ;;;###autoload
 182 (defun executable-interpret (command)
 183   "Run script with user-specified args, and collect output in a buffer.
 184 While script runs asynchronously, you can use the \\[next-error]
 185 command to find the next error.  The buffer is also in `comint-mode' and
 186 `compilation-shell-minor-mode', so that you can answer any prompts."
 187   (interactive (list (read-string "Run script: "
 188                                   (or executable-command
 189                                       buffer-file-name))))
 190   (require 'compile)
 191   (save-some-buffers (not compilation-ask-about-save))
 192   (set (make-local-variable 'executable-command) command)
 193   (let ((compilation-error-regexp-alist executable-error-regexp-alist))
 194     (compilation-start command t (lambda (_x) "*interpretation*"))))
 195
 196
 197
 198 ;;;###autoload
 199 (defun executable-set-magic (interpreter &optional argument
 200                                          no-query-flag insert-flag)
 201   "Set this buffer's interpreter to INTERPRETER with optional ARGUMENT.
 202 The variables `executable-magicless-file-regexp', `executable-prefix',
 203 `executable-insert', `executable-query' and `executable-chmod' control
 204 when and how magic numbers are inserted or replaced and scripts made
 205 executable."
 206   (interactive
 207    (let* ((name (read-string "Name or file name of interpreter: "))
 208           (arg (read-string (format "Argument for %s: " name))))
 209      (list name arg (eq executable-query 'function) t)))
 210
 211   (setq interpreter (if (file-name-absolute-p interpreter)
 212                         interpreter
 213                       (or (executable-find interpreter)
 214                           (error "Interpreter %s not recognized"
 215                                  interpreter))))
 216
 217   (setq argument (concat (if (string-match "\\`/:" interpreter)
 218                              (replace-match "" nil nil interpreter)
 219                            interpreter)
 220                          (and argument (string< "" argument) " ")
 221                          argument))
 222
 223   (or buffer-read-only
 224       (if buffer-file-name
 225           (string-match executable-magicless-file-regexp
 226                         buffer-file-name))
 227       (not (or insert-flag executable-insert))
 228       (> (point-min) 1)
 229       (save-excursion
 230         (goto-char (point-min))
 231         (add-hook 'after-save-hook 'executable-chmod nil t)
 232         (if (looking-at "#![ \t]*\\(.*\\)$")
 233             (and (goto-char (match-beginning 1))
 234                  ;; If the line ends in a space,
 235                  ;; don't offer to change it.
 236                  (not (= (char-after (1- (match-end 1))) ?\s))
 237                  (not (string= argument
 238                                (buffer-substring (point) (match-end 1))))
 239                  (if (or (not executable-query) no-query-flag
 240                          (save-window-excursion
 241                            ;; Make buffer visible before question.
 242                            (switch-to-buffer (current-buffer))
 243                            (y-or-n-p (format-message
 244                                       "Replace magic number by `%s%s'? "
 245                                       executable-prefix argument))))
 246                      (progn
 247                        (replace-match argument t t nil 1)
 248                        (message "Magic number changed to `%s'"
 249                                 (concat executable-prefix argument)))))
 250           (insert executable-prefix argument ?\n)
 251           (message "Magic number changed to `%s'"
 252                    (concat executable-prefix argument)))))
 253     interpreter)
 254
 255
 256
 257 (defun executable-self-display ()
 258   "Turn a text file into a self-displaying Un*x command.
 259 The magic number of such a command displays all lines but itself."
 260   (declare (obsolete nil "25.1"))
 261   (interactive)
 262   (if (eq this-command 'executable-self-display)
 263       (setq this-command 'executable-set-magic))
 264   (executable-set-magic executable-self-display "-n+2"))
 265
 266 ;;;###autoload
 267 (defun executable-make-buffer-file-executable-if-script-p ()
 268   "Make file executable according to umask if not already executable.
 269 If file already has any execute bits set at all, do not change existing
 270 file modes."
 271   (and (>= (buffer-size) 2)
 272        (save-restriction
 273          (widen)
 274          (string= "#!" (buffer-substring (point-min) (+ 2 (point-min)))))
 275        ;; Eg file-modes can return nil (bug#9879).  It should not,
 276        ;; in this context, but we should handle it all the same.
 277        (with-demoted-errors "Unable to make file executable: %s"
 278          (let* ((current-mode (file-modes (buffer-file-name)))
 279                 (add-mode (logand ?\111 (default-file-modes))))
 280            (or (/= (logand ?\111 current-mode) 0)
 281                (zerop add-mode)
 282                (set-file-modes (buffer-file-name)
 283                                (logior current-mode add-mode)))))))
 284
 285 (provide 'executable)
 286
 287 ;;; executable.el ends here