(defgroup savehist nil
"Save minibuffer history."
(defcustom savehist-mode nil
"Mode for automatic saving of minibuffer history.
Set this by calling the `savehist-mode' function or using the customize
:set (lambda (symbol value) (savehist-mode (or value 0)))
(defcustom savehist-save-minibuffer-history t
"*If non-nil, save all recorded minibuffer histories.
If you want to save only specific histories, use `savehist-save-hook' to
modify the value of `savehist-minibuffer-history-variables'."
(defcustom savehist-additional-variables ()
"*List of additional variables to save.
Each element is a symbol whose value will be persisted across Emacs
sessions that use savehist. The contents of variables should be
printable with the Lisp printer. You don't need to add minibuffer
history variables to this list, all minibuffer histories will be
saved automatically as long as `savehist-save-minibuffer-history' is
User options should be saved with the customize interface. This
list is useful for saving automatically updated variables that are not
minibuffer histories, such as `compile-command' or `kill-ring'."
:type '(repeat variable)
(defcustom savehist-ignored-variables nil "*List of additional variables not to save."
:type '(repeat variable)
((file-exists-p "~/.emacs-history") "~/.emacs-history")
((and (not (featurep 'xemacs)) (file-directory-p "~/.emacs.d/"))
((and (featurep 'xemacs) (file-directory-p "~/.xemacs/"))
"*File name where minibuffer history is saved to and loaded from.
The minibuffer history is a series of Lisp expressions loaded
automatically when `savehist-mode' is turned on. See `savehist-mode'
for more details.
If you want your minibuffer history shared between Emacs and XEmacs,
customize this value and make sure that `savehist-coding-system' is
set to a coding system that exists in both emacsen."
(defcustom savehist-file-modes #o600
"*Default permissions of the history file.
This is decimal, not octal. The default is 384 (0600 in octal).
Set to nil to use the default permissions that Emacs uses, typically
mandated by umask. The default is a bit more restrictive to protect
the user's privacy."
(defcustom savehist-autosave-interval (* 5 60)
"*The interval between autosaves of minibuffer history.
If set to nil, disables timer-based autosaving."
(defcustom savehist-mode-hook nil
"Hook called when `savehist-mode' is turned on."
(defcustom savehist-save-hook nil
"Hook called by `savehist-save' before saving the variables.
You can use this hook to influence choice and content of variables to
(defvar savehist-coding-system (if (and (featurep 'xemacs)
(<= emacs-major-version 21)
(< emacs-minor-version 5))
"The coding system savehist uses for saving the minibuffer history.
Changing this value while Emacs is running is supported, but considered
unwise, unless you know what you are doing.")
(defvar savehist-timer nil)
(defvar savehist-last-checksum nil)
(defvar savehist-minibuffer-history-variables nil
"List of minibuffer histories.
The contents of this variable is built while Emacs is running, and saved
along with minibuffer history. You can change its value off
`savehist-save-hook' to influence which variables are saved.")
(defconst savehist-no-conversion (if (featurep 'xemacs) 'binary 'no-conversion)
"Coding system without any conversion.
This is used for calculating an internal checksum. Should be as fast
as possible, ideally simply exposing the internal representation of
(defvar savehist-loaded nil
"Whether the history has already been loaded.
This prevents toggling `savehist-mode' from destroying existing
(when (featurep 'xemacs)
(defvar history-length 100))
(defun savehist-mode (arg)
Positive ARG turns on `savehist-mode'. When on, savehist-mode causes
minibuffer history to be saved periodically and when exiting Emacs.
When turned on for the first time in an Emacs session, it causes the
previous minibuffer history to be loaded from `savehist-file'.
This mode should normally be turned on from your Emacs init file.
Calling it at any other time replaces your current minibuffer histories,
which is probably undesirable."
(if (null arg)
(> (prefix-numeric-value arg) 0)))
(if (not savehist-mode)
(when (and (not savehist-loaded)
(load savehist-file nil (not (interactive-p)))
(setq savehist-loaded t))
(setq savehist-mode nil)
(signal (car errvar) (cdr errvar)))))
(add-minor-mode 'savehist-mode "")
(defun savehist-load ()
"Obsolete function provided for transition from old versions of savehist.
Don't call this from new code, use (savehist-mode 1) instead.
This function loads the variables stored in `savehist-file' and turns on
`savehist-mode'. If `savehist-file' is in the old format that doesn't
record the value of `savehist-minibuffer-history-variables', that value
is deducted from the contents of the file."
(when (null savehist-minibuffer-history-variables)
(let ((vars ()) form)
(while (setq form (condition-case nil
(read (current-buffer)) (error nil)))
(push (nth 1 form) vars))
(make-obsolete 'savehist-load 'savehist-mode)
(defun savehist-install ()
"Hook savehist into Emacs.
Normally invoked by calling `savehist-mode' to set the minor mode.
Installs `savehist-autosave' in `kill-emacs-hook' and on a timer.
To undo this, call `savehist-uninstall'."
(add-hook 'minibuffer-setup-hook 'savehist-minibuffer-hook)
(add-hook 'kill-emacs-hook 'savehist-autosave)
(when (and savehist-autosave-interval
(if (featurep 'xemacs)
"savehist" 'savehist-autosave savehist-autosave-interval
(defun savehist-uninstall ()
"Undo installing savehist.
Normally invoked by calling `savehist-mode' to unset the minor mode."
(remove-hook 'minibuffer-setup-hook 'savehist-minibuffer-hook)
(remove-hook 'kill-emacs-hook 'savehist-autosave)
(if (featurep 'xemacs)
(setq savehist-timer nil)))
(defun savehist-save (&optional auto-save)
"Save the values of minibuffer history variables.
Unbound symbols referenced in `savehist-additional-variables' are ignored.
If AUTO-SAVE is non-nil, compare the saved contents to the one last saved,
and don't save the buffer if they are the same."
(format ";; -*- mode: emacs-lisp; coding: %s -*-\n" savehist-coding-system)
";; Minibuffer history file, automatically generated by `savehist'.\n\n")
(let ((print-length nil)
(prin1 `(setq savehist-minibuffer-history-variables
(dolist (symbol savehist-minibuffer-history-variables)
(when (boundp symbol)
(let ((value (savehist-trim-history (symbol-value symbol))))
(when value (prin1 `(setq ,symbol ',value) (current-buffer))
(dolist (symbol savehist-additional-variables)
(when (boundp symbol)
(let ((value (symbol-value symbol)))
(when (savehist-printable value)
(prin1 `(setq ,symbol ',value) (current-buffer))
(let ((checksum (md5 (current-buffer) nil nil savehist-no-conversion)))
(unless (and auto-save (equal checksum savehist-last-checksum))
(let ((file-precious-flag t)
(write-region (point-min) (point-max) savehist-file nil
(unless (interactive-p) 'quiet)))
(set-file-modes savehist-file savehist-file-modes))
(setq savehist-last-checksum checksum)))))
(defun savehist-autosave ()
"Save the minibuffer history if it has been modified since the last save.
Does nothing if `savehist-mode' is off."
(defun savehist-trim-history (value)
"Retain only the first `history-length' items in VALUE.
Only used under XEmacs, which doesn't (yet) implement automatic
trimming of history lists to `history-length' items."
(if (and (featurep 'xemacs)
(> (length value) history-length))
(loop repeat history-length collect (pop value))
(defun savehist-printable (value)
"Return non-nil if VALUE is printable."
(let ((print-readably t) (print-level nil))
(prin1 value (current-buffer))
(defun savehist-minibuffer-hook ()
(unless (or (eq minibuffer-history-variable t)
(memq minibuffer-history-variable savehist-ignored-variables))