diff options
Diffstat (limited to 'lisp/image.el')
| -rw-r--r-- | lisp/image.el | 34 |
1 files changed, 26 insertions, 8 deletions
diff --git a/lisp/image.el b/lisp/image.el index 22fa704d220..c9269abce3e 100644 --- a/lisp/image.el +++ b/lisp/image.el @@ -65,13 +65,16 @@ a non-nil value, TYPE is the image's type.") When the name of an image file match REGEXP, it is assumed to be of image type IMAGE-TYPE.") +;; We rely on `auto-mode-alist' to detect xbm and xpm files, instead +;; of content autodetection. Their contents are just C code, so it is +;; easy to generate false matches. (defvar image-type-auto-detectable '((pbm . t) - (xbm . t) + (xbm . nil) (bmp . maybe) (gif . maybe) (png . maybe) - (xpm . maybe) + (xpm . nil) (jpeg . maybe) (tiff . maybe) (postscript . nil)) @@ -340,15 +343,30 @@ Image types are symbols like `xbm' or `jpeg'." ;;;###autoload (defun image-type-auto-detected-p () "Return t iff the current buffer contains an auto-detectable image. -Whether image types are auto-detectable or not depends on the setting -of the variable `image-type-auto-detectable'. - -This function is intended to be used from `magic-mode-alist' (which see)." +This function is intended to be used from `magic-mode-alist' (which see). + +First, compare the beginning of the buffer with `image-type-header-regexps'. +If an appropriate image type is found, check if that image type can be +autodetected using the variable `image-type-auto-detectable'. Finally, +if `buffer-file-name' is non-nil, check if it matches another major mode +in `auto-mode-alist' apart from `image-mode'; if there is another match, +the autodetection is considered to have failed. Return t if all the above +steps succeed." (let* ((type (image-type-from-buffer)) (auto (and type (cdr (assq type image-type-auto-detectable))))) (and auto - (or (eq auto t) - (image-type-available-p type))))) + (or (eq auto t) (image-type-available-p type)) + (or (null buffer-file-name) + (not (assoc-default + buffer-file-name + (delq nil (mapcar + (lambda (elt) + (unless (memq (or (car-safe (cdr elt)) + (cdr elt)) + '(image-mode image-mode-maybe)) + elt)) + auto-mode-alist)) + 'string-match)))))) ;;;###autoload |