;;; loadhist.el --- lisp functions for working with feature groups
-;; Copyright (C) 1995, 1998, 2000 Free Software Foundation, Inc.
+;; Copyright (C) 1995, 1998, 2000, 2002, 2003, 2004,
+;; 2005, 2006 Free Software Foundation, Inc.
;; Author: Eric S. Raymond <esr@snark.thyrsus.com>
;; Maintainer: FSF
;; 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., 59 Temple Place - Suite 330,
-;; Boston, MA 02111-1307, USA.
+;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+;; Boston, MA 02110-1301, USA.
;;; Commentary:
;;; Code:
+(eval-when-compile (require 'cl))
+
(defun feature-symbols (feature)
"Return the file and list of definitions associated with FEATURE.
The value is actually the element of `load-history'
(error "%S is not a currently loaded feature" feature)
(car (feature-symbols feature))))
+(defun file-loadhist-lookup (file)
+ "Return the `load-history' element for FILE.
+FILE can be a file name, or a library name.
+A library name is equivalent to the file name that `load-library' would load."
+ ;; First look for FILE as given.
+ (let ((symbols (assoc file load-history)))
+ ;; Try converting a library name to an absolute file name.
+ (and (null symbols)
+ (let ((absname
+ (locate-file file load-path (get-load-suffixes))))
+ (and absname (not (equal absname file))
+ (setq symbols (cdr (assoc absname load-history))))))
+ symbols))
+
(defun file-provides (file)
- "Return the list of features provided by FILE."
- (let ((symbols (cdr (assoc file load-history)))
+ "Return the list of features provided by FILE as it was loaded.
+FILE can be a file name, or a library name.
+A library name is equivalent to the file name that `load-library' would load."
+ (let ((symbols (file-loadhist-lookup file))
provides)
(mapc (lambda (x)
(if (and (consp x) (eq (car x) 'provide))
provides))
(defun file-requires (file)
- "Return the list of features required by FILE."
- (let ((symbols (cdr (assoc file load-history)))
+ "Return the list of features required by FILE as it was loaded.
+FILE can be a file name, or a library name.
+A library name is equivalent to the file name that `load-library' would load."
+ (let ((symbols (file-loadhist-lookup file))
requires)
(mapc (lambda (x)
(if (and (consp x) (eq (car x) 'require))
(defun file-dependents (file)
"Return the list of loaded libraries that depend on FILE.
-This can include FILE itself."
+This can include FILE itself.
+FILE can be a file name, or a library name.
+A library name is equivalent to the file name that `load-library' would load."
(let ((provides (file-provides file))
(dependents nil))
(dolist (x load-history dependents)
features)
nil t)))
-(defvar loadhist-hook-functions
+(defvaralias 'loadhist-hook-functions 'unload-feature-special-hooks)
+(defvar unload-feature-special-hooks
'(after-change-functions
after-insert-file-functions auto-fill-function
before-change-functions blink-paren-function
`-hook' or `-hooks', from which `unload-feature' tries to remove
pertinent symbols.")
+(defvar unload-hook-features-list nil
+ "List of features of the package being unloaded.
+
+This is meant to be used by FEATURE-unload-hook hooks, see the
+documentation of `unload-feature' for details.")
+
;;;###autoload
(defun unload-feature (feature &optional force)
"Unload the library that provided FEATURE, restoring all its autoloads.
If the feature is required by any other loaded code, and prefix arg FORCE
-is nil, raise an error."
+is nil, raise an error.
+
+This function tries to undo modifications made by the package to
+hooks. Packages may define a hook FEATURE-unload-hook that is called
+instead of the normal heuristics for doing this. Such a hook should
+undo all the relevant global state changes that may have been made by
+loading the package or executing functions in it. It has access to
+the package's feature list (before anything is unbound) in the
+variable `unload-hook-features-list' and could remove features from it
+in the event that the package has done something normally-ill-advised,
+such as redefining an Emacs function."
(interactive (list (read-feature "Feature: ") current-prefix-arg))
- (if (not (featurep feature))
- (error "%s is not a currently loaded feature" (symbol-name feature)))
- (if (not force)
- (let* ((file (feature-file feature))
- (dependents (delete file (copy-sequence (file-dependents file)))))
- (if dependents
- (error "Loaded libraries %s depend on %s"
- (prin1-to-string dependents) file))))
- (let* ((flist (feature-symbols feature))
- (file (car flist))
+ (unless (featurep feature)
+ (error "%s is not a currently loaded feature" (symbol-name feature)))
+ (unless force
+ (let* ((file (feature-file feature))
+ (dependents (delete file (copy-sequence (file-dependents file)))))
+ (when dependents
+ (error "Loaded libraries %s depend on %s"
+ (prin1-to-string dependents) file))))
+ (let* ((unload-hook-features-list (feature-symbols feature))
+ (file (pop unload-hook-features-list))
(unload-hook (intern-soft (concat (symbol-name feature)
"-unload-hook"))))
;; Try to avoid losing badly when hooks installed in critical
;; places go away. (Some packages install things on
;; `kill-buffer-hook', `activate-menubar-hook' and the like.)
- ;; First off, provide a clean way for package `foo' to arrange
- ;; this by defining `foo-unload-hook'.
+ ;; First off, provide a clean way for package FOO to arrange
+ ;; this by adding hooks on the variable `FOO-unload-hook'.
(if unload-hook
(run-hooks unload-hook)
;; Otherwise, do our best. Look through the obarray for symbols
;; normally works.
(mapatoms
(lambda (x)
- (if (or (and (boundp x) ; Random hooks.
- (consp (symbol-value x))
- (string-match "-hooks?\\'" (symbol-name x)))
- (and (boundp x) ; Known abnormal hooks etc.
- (memq x loadhist-hook-functions)))
- (dolist (y (cdr flist))
- (remove-hook x y))))))
- (if (fboundp 'elp-restore-function) ; remove ELP stuff first
- (dolist (elt (cdr flist))
- (if (symbolp elt)
- (elp-restore-function elt))))
- (mapc
- (lambda (x)
- (cond ((stringp x) nil)
- ((consp x)
- ;; Remove any feature names that this file provided.
- (if (eq (car x) 'provide)
- (setq features (delq (cdr x) features)))
- (when (eq (car x) 'defvar)
- ;; Kill local values as much as possible.
- (dolist (buf (buffer-list))
- (with-current-buffer buf
- (kill-local-variable (cdr x))))
- ;; Get rid of the default binding if we can.
- (unless (local-variable-if-set-p (cdr x))
- (makunbound (cdr x)))))
- (t
- (when (fboundp x)
- (if (fboundp 'ad-unadvise)
- (ad-unadvise x))
- (fmakunbound x)
- (let ((aload (get x 'autoload)))
- (if aload (fset x (cons 'autoload aload))))))))
- (cdr flist))
+ (when (and (boundp x)
+ (or (and (consp (symbol-value x)) ; Random hooks.
+ (string-match "-hooks?\\'" (symbol-name x)))
+ (memq x unload-feature-special-hooks))) ; Known abnormal hooks etc.
+ (dolist (y unload-hook-features-list)
+ (when (and (eq (car-safe y) 'defun)
+ (not (get (cdr y) 'autoload)))
+ (remove-hook x (cdr y)))))))
+ ;; Remove any feature-symbols from auto-mode-alist as well.
+ (dolist (y unload-hook-features-list)
+ (when (and (eq (car-safe y) 'defun)
+ (not (get (cdr y) 'autoload)))
+ (setq auto-mode-alist
+ (rassq-delete-all (cdr y) auto-mode-alist)))))
+ (when (fboundp 'elp-restore-function) ; remove ELP stuff first
+ (dolist (elt unload-hook-features-list)
+ (when (symbolp elt)
+ (elp-restore-function elt))))
+ (dolist (x unload-hook-features-list)
+ (if (consp x)
+ (case (car x)
+ ;; Remove any feature names that this file provided.
+ (provide
+ (setq features (delq (cdr x) features)))
+ (defun
+ (let ((fun (cdr x)))
+ (when (fboundp fun)
+ (when (fboundp 'ad-unadvise)
+ (ad-unadvise fun))
+ (let ((aload (get fun 'autoload)))
+ (if aload
+ (fset fun (cons 'autoload aload))
+ (fmakunbound fun))))))
+ (require nil)
+ (t (message "Unexpected element %s in load-history" x)))
+ ;; Kill local values as much as possible.
+ (dolist (buf (buffer-list))
+ (with-current-buffer buf
+ (if (and (boundp x) (timerp (symbol-value x)))
+ (cancel-timer (symbol-value x)))
+ (kill-local-variable x)))
+ (if (and (boundp x) (timerp (symbol-value x)))
+ (cancel-timer (symbol-value x)))
+ ;; Get rid of the default binding if we can.
+ (unless (local-variable-if-set-p x)
+ (makunbound x))))
;; Delete the load-history element for this file.
- (let ((elt (assoc file load-history)))
- (setq load-history (delq elt load-history)))))
+ (setq load-history (delq (assoc file load-history) load-history))))
(provide 'loadhist)
-;;; arch-tag: 70bb846a-c413-4f01-bf88-78dba4ac0798
+;; arch-tag: 70bb846a-c413-4f01-bf88-78dba4ac0798
;;; loadhist.el ends here