lisp/obsolete/uncompress.el

   1 ;;; uncompress.el --- auto-decompression hook for visiting .Z files
   2
   3 ;; Copyright (C) 1992, 1994, 2001, 2002, 2003, 2004,
   4 ;;   2005, 2006, 2007 Free Software Foundation, Inc.
   5
   6 ;; Maintainer: FSF
   7 ;; Keywords: files
   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, or (at your option)
  14 ;; 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; see the file COPYING.  If not, write to the
  23 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  24 ;; Boston, MA 02110-1301, USA.
  25
  26 ;;; Commentary:
  27
  28 ;; This package can be used to arrange for automatic uncompress of
  29 ;; compressed files when they are visited.
  30 ;; All that's necessary is to load it.  This can conveniently be done from
  31 ;; your .emacs file.
  32
  33 ;; M-x auto-compression-mode is a more modern replacement for this package.
  34
  35 ;;; Code:
  36
  37 ;; When we are about to make a backup file,
  38 ;; uncompress the file we visited
  39 ;; so that making the backup can work properly.
  40 ;; This is used as a write-file-hook.
  41
  42 (defvar uncompress-program "gunzip"
  43   "Program to use for uncompression.")
  44
  45 (defun uncompress-backup-file ()
  46   (and buffer-file-name make-backup-files (not buffer-backed-up)
  47        (not (file-exists-p buffer-file-name))
  48        (call-process uncompress-program nil nil nil buffer-file-name))
  49   nil)
  50
  51 (or (assoc "\\.Z$" auto-mode-alist)
  52     (setq auto-mode-alist
  53           (cons '("\\.Z$" . uncompress-while-visiting) auto-mode-alist)))
  54 (or (assoc "\\.gz$" auto-mode-alist)
  55     (setq auto-mode-alist
  56           (cons '("\\.gz$" . uncompress-while-visiting) auto-mode-alist)))
  57 (or (assoc "\\.tgz$" auto-mode-alist)
  58     (setq auto-mode-alist
  59           (cons '("\\.tgz$" . uncompress-while-visiting) auto-mode-alist)))
  60
  61 (defun uncompress-while-visiting ()
  62   "Temporary \"major mode\" used for .Z and .gz files, to uncompress them.
  63 It then selects a major mode from the uncompressed file name and contents."
  64   (if (and (not (null buffer-file-name))
  65            (string-match "\\.Z$" buffer-file-name))
  66       (set-visited-file-name
  67        (substring buffer-file-name 0 (match-beginning 0)))
  68     (if (and (not (null buffer-file-name))
  69              (string-match "\\.gz$" buffer-file-name))
  70         (set-visited-file-name
  71          (substring buffer-file-name 0 (match-beginning 0)))
  72       (if (and (not (null buffer-file-name))
  73                (string-match "\\.tgz$" buffer-file-name))
  74           (set-visited-file-name
  75            (concat (substring buffer-file-name 0 (match-beginning 0)) ".tar")))))
  76   (message "Uncompressing...")
  77   (let ((buffer-read-only nil)
  78         (coding-system-for-write 'no-conversion)
  79         (coding-system-for-read
  80          (car (find-operation-coding-system
  81                'insert-file-contents
  82                buffer-file-name t))))
  83     (shell-command-on-region (point-min) (point-max) uncompress-program t))
  84   (goto-char (point-min))
  85   (message "Uncompressing...done")
  86   (set-buffer-modified-p nil)
  87   (add-hook 'write-file-functions 'uncompress-backup-file nil t)
  88   (normal-mode))
  89
  90 (add-hook 'find-file-not-found-functions 'find-compressed-version)
  91
  92 (defun find-compressed-version ()
  93   "Hook to read and uncompress the compressed version of a file."
  94   ;; Just pretend we had visited the compressed file,
  95   ;; and uncompress-while-visiting will do the rest.
  96   (let (name)
  97     (if (file-exists-p (setq name (concat buffer-file-name ".Z")))
  98         (setq buffer-file-name name)
  99       (if (file-exists-p (setq name (concat buffer-file-name ".gz")))
 100           (setq buffer-file-name name)))
 101     (if (eq name buffer-file-name)
 102         (progn
 103           (insert-file-contents buffer-file-name t)
 104           (goto-char (point-min))
 105           ;; No need for this, because error won't be set to t
 106           ;; if this function returns t.
 107           ;; (setq error nil)
 108           t))))
 109
 110 (message "The uncompress package is obsolete; use M-x auto-compression-mode")
 111
 112 (provide 'uncompress)
 113
 114 ;;; arch-tag: 626658d4-fcce-499a-990d-d165f2ed7da3
 115 ;;; uncompress.el ends here