mirror of
https://git.savannah.gnu.org/git/emacs.git
synced 2024-12-29 11:02:01 +00:00
209 lines
7.3 KiB
EmacsLisp
209 lines
7.3 KiB
EmacsLisp
;;; image-file.el --- support for visiting image files
|
|
;;
|
|
;; Copyright (C) 2000, 2001, 2002, 2003, 2004,
|
|
;; 2005 Free Software Foundation, Inc.
|
|
;;
|
|
;; Author: Miles Bader <miles@gnu.org>
|
|
;; Keywords: multimedia
|
|
|
|
;; This file is part of GNU Emacs.
|
|
|
|
;; GNU Emacs is free software; you can redistribute it and/or modify
|
|
;; it under the terms of the GNU General Public License as published by
|
|
;; the Free Software Foundation; either version 2, or (at your option)
|
|
;; any later version.
|
|
|
|
;; GNU Emacs is distributed in the hope that it will be useful,
|
|
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
;; GNU General Public License for more details.
|
|
|
|
;; You should have received a copy of the GNU General Public License
|
|
;; along with GNU Emacs; see the file COPYING. If not, write to the
|
|
;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
|
|
;; Boston, MA 02110-1301, USA.
|
|
|
|
;;; Commentary:
|
|
|
|
;; Defines a file-name-handler hook that transforms visited (or
|
|
;; inserted) image files so that they are displayed by Emacs as
|
|
;; images. This is done by putting a `display' text-property on the
|
|
;; image data, with the image-data still present underneath; if the
|
|
;; resulting buffer file is saved to another name it will correctly save
|
|
;; the image data to the new file.
|
|
|
|
;;; Code:
|
|
|
|
(require 'image)
|
|
|
|
|
|
;;;###autoload
|
|
(defcustom image-file-name-extensions
|
|
'("png" "jpeg" "jpg" "gif" "tiff" "tif" "xbm" "xpm" "pbm" "pgm" "ppm" "pnm")
|
|
"*A list of image-file filename extensions.
|
|
Filenames having one of these extensions are considered image files,
|
|
in addition to those matching `image-file-name-regexps'.
|
|
|
|
See `auto-image-file-mode'; if `auto-image-file-mode' is enabled,
|
|
setting this variable directly does not take effect unless
|
|
`auto-image-file-mode' is re-enabled; this happens automatically when
|
|
the variable is set using \\[customize]."
|
|
:type '(repeat string)
|
|
:set (lambda (sym val)
|
|
(set-default sym val)
|
|
(when auto-image-file-mode
|
|
;; Re-initialize the image-file handler
|
|
(auto-image-file-mode t)))
|
|
:initialize 'custom-initialize-default
|
|
:group 'image)
|
|
|
|
;;;###autoload
|
|
(defcustom image-file-name-regexps nil
|
|
"*List of regexps matching image-file filenames.
|
|
Filenames matching one of these regexps are considered image files,
|
|
in addition to those with an extension in `image-file-name-extensions'.
|
|
|
|
See function `auto-image-file-mode'; if `auto-image-file-mode' is
|
|
enabled, setting this variable directly does not take effect unless
|
|
`auto-image-file-mode' is re-enabled; this happens automatically when
|
|
the variable is set using \\[customize]."
|
|
:type '(repeat regexp)
|
|
:set (lambda (sym val)
|
|
(set-default sym val)
|
|
(when auto-image-file-mode
|
|
;; Re-initialize the image-file handler
|
|
(auto-image-file-mode t)))
|
|
:initialize 'custom-initialize-default
|
|
:group 'image)
|
|
|
|
|
|
;;;###autoload
|
|
(defun image-file-name-regexp ()
|
|
"Return a regular expression matching image-file filenames."
|
|
(let ((exts-regexp
|
|
(and image-file-name-extensions
|
|
(concat "\\."
|
|
(regexp-opt (nconc (mapcar #'upcase
|
|
image-file-name-extensions)
|
|
image-file-name-extensions)
|
|
t)
|
|
"\\'"))))
|
|
(if image-file-name-regexps
|
|
(mapconcat 'identity
|
|
(if exts-regexp
|
|
(cons exts-regexp image-file-name-regexps)
|
|
image-file-name-regexps)
|
|
"\\|")
|
|
exts-regexp)))
|
|
|
|
|
|
;;;###autoload
|
|
(defun insert-image-file (file &optional visit beg end replace)
|
|
"Insert the image file FILE into the current buffer.
|
|
Optional arguments VISIT, BEG, END, and REPLACE are interpreted as for
|
|
the command `insert-file-contents'."
|
|
(let ((rval
|
|
(image-file-call-underlying #'insert-file-contents-literally
|
|
'insert-file-contents
|
|
file visit beg end replace)))
|
|
;; Turn the image data into a real image, but only if the whole file
|
|
;; was inserted
|
|
(when (and (or (null beg) (zerop beg)) (null end))
|
|
(let* ((ibeg (point))
|
|
(iend (+ (point) (cadr rval)))
|
|
(visitingp (and visit (= ibeg (point-min)) (= iend (point-max))))
|
|
(data
|
|
(string-make-unibyte
|
|
(buffer-substring-no-properties ibeg iend)))
|
|
(image
|
|
(create-image data nil t))
|
|
(props
|
|
`(display ,image
|
|
yank-handler
|
|
(image-file-yank-handler nil t)
|
|
intangible ,image
|
|
rear-nonsticky (display intangible)
|
|
;; This a cheap attempt to make the whole buffer
|
|
;; read-only when we're visiting the file (as
|
|
;; opposed to just inserting it).
|
|
,@(and visitingp
|
|
'(read-only t front-sticky (read-only))))))
|
|
(add-text-properties ibeg iend props)
|
|
(when visitingp
|
|
;; Inhibit the cursor when the buffer contains only an image,
|
|
;; because cursors look very strange on top of images.
|
|
(setq cursor-type nil)
|
|
;; This just makes the arrow displayed in the right fringe
|
|
;; area look correct when the image is wider than the window.
|
|
(setq truncate-lines t))))
|
|
rval))
|
|
|
|
;; We use a yank-handler to make yanked images unique, so that
|
|
;; yanking two copies of the same image next to each other are
|
|
;; recognized as two different images.
|
|
(defun image-file-yank-handler (string)
|
|
"Yank handler for inserting an image into a buffer."
|
|
(let ((len (length string))
|
|
(image (get-text-property 0 'display string)))
|
|
(remove-text-properties 0 len yank-excluded-properties string)
|
|
(if (consp image)
|
|
(add-text-properties 0
|
|
(or (next-single-property-change 0 'image-counter string)
|
|
(length string))
|
|
`(display
|
|
,(cons (car image) (cdr image))
|
|
yank-handler
|
|
,(cons 'image-file-yank-handler '(nil t)))
|
|
string))
|
|
(insert string)))
|
|
|
|
(put 'image-file-handler 'safe-magic t)
|
|
(defun image-file-handler (operation &rest args)
|
|
"Filename handler for inserting image files.
|
|
OPERATION is the operation to perform, on ARGS.
|
|
See `file-name-handler-alist' for details."
|
|
(if (and (eq operation 'insert-file-contents)
|
|
auto-image-file-mode)
|
|
(apply #'insert-image-file args)
|
|
;; We don't handle OPERATION, use another handler or the default
|
|
(apply #'image-file-call-underlying operation operation args)))
|
|
|
|
(defun image-file-call-underlying (function operation &rest args)
|
|
"Call FUNCTION with `image-file-handler' and OPERATION inhibited.
|
|
Optional argument ARGS are the arguments to call FUNCTION with."
|
|
(let ((inhibit-file-name-handlers
|
|
(cons 'image-file-handler
|
|
(and (eq inhibit-file-name-operation operation)
|
|
inhibit-file-name-handlers)))
|
|
(inhibit-file-name-operation operation))
|
|
(apply function args)))
|
|
|
|
|
|
;;;###autoload
|
|
(define-minor-mode auto-image-file-mode
|
|
"Toggle visiting of image files as images.
|
|
With prefix argument ARG, turn on if positive, otherwise off.
|
|
Returns non-nil if the new state is enabled.
|
|
|
|
Image files are those whose name has an extension in
|
|
`image-file-name-extensions', or matches a regexp in
|
|
`image-file-name-regexps'."
|
|
:global t
|
|
:group 'image
|
|
;; Remove existing handler
|
|
(let ((existing-entry
|
|
(rassq 'image-file-handler file-name-handler-alist)))
|
|
(when existing-entry
|
|
(setq file-name-handler-alist
|
|
(delq existing-entry file-name-handler-alist))))
|
|
;; Add new handler, if enabled
|
|
(when auto-image-file-mode
|
|
(push (cons (image-file-name-regexp) 'image-file-handler)
|
|
file-name-handler-alist)))
|
|
|
|
|
|
(provide 'image-file)
|
|
|
|
;;; arch-tag: 04cafe36-f7ba-4c80-9f47-4cb656520ce1
|
|
;;; image-file.el ends here
|