view lisp/itimer-autosave.el @ 5882:bbe4146603db

Reduce regexp usage, now CL-oriented non-regexp code available, core Lisp lisp/ChangeLog addition: 2015-04-01 Aidan Kehoe <kehoea@parhasard.net> When calling #'string-match with a REGEXP without regular expression special characters, call #'search, #'mismatch, #'find, etc. instead, making our code less likely to side-effect other functions' match data and a little faster. * apropos.el (apropos-command): * apropos.el (apropos): Call (position ?\n ...) rather than (string-match "\n" ...) here. * buff-menu.el: * buff-menu.el (buffers-menu-omit-invisible-buffers): Don't fire up the regexp engine just to check if a string starts with a space. * buff-menu.el (select-buffers-tab-buffers-by-mode): Don't fire up the regexp engine just to compare mode basenames. * buff-menu.el (format-buffers-tab-line): * buff-menu.el (build-buffers-tab-internal): Moved to being a label within the following. * buff-menu.el (buffers-tab-items): Use the label. * bytecomp.el (byte-compile-log-1): Don't fire up the regexp engine just to look for a newline. * cus-edit.el (get): Ditto. * cus-edit.el (custom-variable-value-create): Ditto, but for a colon. * descr-text.el (describe-text-sexp): Ditto. * descr-text.el (describe-char-unicode-data): Use #'split-string-by-char given that we're just looking for a semicolon. * descr-text.el (describe-char): Don't fire up the regexp engine just to look for a newline. * disass.el (disassemble-internal): Ditto. * files.el (file-name-sans-extension): Implement this using #'position. * files.el (file-name-extension): Correct this function's docstring, implement it in terms of #'position. * files.el (insert-directory): Don't fire up the regexp engine to split a string by space; don't reverse the list of switches, this is actually a longstand bug as far as I can see. * gnuserv.el (gnuserv-process-filter): Use #'position here, instead of consing inside #'split-string needlessly. * gtk-file-dialog.el (gtk-file-dialog-update-dropdown): Use #'split-string-by-char here, don't fire up #'split-string for directory-sep-char. * gtk-font-menu.el (hack-font-truename): Implement this more cheaply in terms of #'find, #'split-string-by-char, #'equal, rather than #'string-match, #'split-string, #'string-equal. * hyper-apropos.el (hyper-apropos-grok-functions): * hyper-apropos.el (hyper-apropos-grok-variables): Look for a newline using #'position rather than #'string-match in these functions. * info.el (Info-insert-dir): * info.el (Info-insert-file-contents): * info.el (Info-follow-reference): * info.el (Info-extract-menu-node-name): * info.el (Info-menu): Look for fixed strings using #'position or #'search as appropriate in this file. * ldap.el (ldap-decode-string): * ldap.el (ldap-encode-string): #'encode-coding-string, #'decode-coding-string are always available, don't check if they're fboundp. * ldap.el (ldap-decode-address): * ldap.el (ldap-encode-address): Use #'split-string-by-char in these functions. * lisp-mnt.el (lm-creation-date): * lisp-mnt.el (lm-last-modified-date): Don't fire up the regexp engine just to look for spaces in this file. * menubar-items.el (default-menubar): Use (not (mismatch ...)) rather than #'string-match here, for simple regexp. Use (search "beta" ...) rather than (string-match "beta" ...) * menubar-items.el (sort-buffers-menu-alphabetically): * menubar-items.el (sort-buffers-menu-by-mode-then-alphabetically): * menubar-items.el (group-buffers-menu-by-mode-then-alphabetically): Don't fire up the regexp engine to check if a string starts with a space or an asterisk. Use the more fine-grained results of #'compare-strings; compare case-insensitively for the buffer menu. * menubar-items.el (list-all-buffers): * menubar-items.el (tutorials-menu-filter): Use #'equal rather than #'string-equal, which, in this context, has the drawback of not having a bytecode, and no redeeming features. * minibuf.el: * minibuf.el (un-substitute-in-file-name): Use #'count, rather than counting the occurences of $ using the regexp engine. * minibuf.el (read-file-name-internal-1): Don't fire up the regexp engine to search for ?=. * mouse.el (mouse-eval-sexp): Check for newline with #'find. * msw-font-menu.el (mswindows-reset-device-font-menus): Split a string by newline with #'split-string-by-char. * mule/japanese.el: * mule/japanese.el ("Japanese"): Use #'search rather than #'string-match; canoncase before comparing; fix a bug I had introduced where I had been making case insensitive comparisons where the case mattered. * mule/korea-util.el (default-korean-keyboard): Look for ?3 using #'find, not #'string-march. * mule/korea-util.el (quail-hangul-switch-hanja): Search for a fixed string using #'search. * mule/mule-cmds.el (set-locale-for-language-environment): #'position, #'substitute rather than #'string-match, #'replace-in-string. * newcomment.el (comment-make-extra-lines): Use #'search rather than #'string-match for a simple string. * package-get.el (package-get-remote-filename): Use #'position when looking for ?@ * process.el (setenv): * process.el (read-envvar-name): Use #'position when looking for ?=. * replace.el (map-query-replace-regexp): Use #'split-string-by-char instead of using an inline implementation of it. * select.el (select-convert-from-cf-text): * select.el (select-convert-from-cf-unicodetext): Use #'position rather than #'string-match in these functions. * setup-paths.el (paths-emacs-data-root-p): Use #'search when looking for simple string. * sound.el (load-sound-file): Use #'split-string-by-char rather than an inline reimplementation of same. * startup.el (splash-screen-window-body): * startup.el (splash-screen-tty-body): Search for simple strings using #'search. * version.el (emacs-version): Ditto. * x-font-menu.el (hack-font-truename): Implement this more cheaply in terms of #'find, #'split-string-by-char, #'equal, rather than #'string-match, #'split-string, #'string-equal. * x-font-menu.el (x-reset-device-font-menus-core): Use #'split-string-by-char here. * x-init.el (x-initialize-keyboard): Search for a simple string using #'search.
author Aidan Kehoe <kehoea@parhasard.net>
date Wed, 01 Apr 2015 14:28:20 +0100
parents 308d34e9f07d
children
line wrap: on
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;;; itimer-autosave.el --- Autosave functions with itimers

;; Copyright status unknown

;; Maintainer: XEmacs Development Team
;; Keywords: internal, dumped

;; This file is part of XEmacs.

;; XEmacs 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 3 of the License, or (at your
;; option) any later version.

;; XEmacs 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 XEmacs.  If not, see <http://www.gnu.org/licenses/>.

;;; Synched up with: Not in FSF.

;;; Commentary:

;; This file is dumped with XEmacs.

;; itimer-driven auto-saves

;;; Code:

;jwz: this is preloaded so don't ;;;###autoload
(defvar auto-save-timeout 960
  "*Number of seconds idle time before auto-save.
Zero or nil means disable auto-saving due to idleness.

The actual amount of idle time between auto-saves is logarithmically related
to the size of the current buffer.  This variable is the number of seconds
after which an auto-save will happen when the current buffer is 50k or less;
the timeout will be 2 1/4 times this in a 200k buffer, 3 3/4 times this in a
1000k buffer, and 4 1/2 times this in a 2000k buffer.

See also the variable `auto-save-interval', which controls auto-saving based
on the number of characters typed.")

;jwz: this is preloaded so don't ;;;###autoload
(defvar auto-gc-threshold (/ gc-cons-threshold 3)
  "*GC when this many bytes have been consed since the last GC, 
and the user has been idle for `auto-save-timeout' seconds.")

(defun auto-save-itimer ()
  "For use as a itimer callback function.
Auto-saves and garbage-collects based on the size of the current buffer
and the value of `auto-save-timeout', `auto-gc-threshold', and the current
keyboard idle-time."
  (if (or (null auto-save-timeout)
	  (<= auto-save-timeout 0)
	  (eq (minibuffer-window) (selected-window)))
      nil
    (let ((buf-size (1+ (ash (buffer-size) -8)))
	  (delay-level 0)
	  (now (current-time))
	  delay)
      (while (> buf-size 64)
	(setq delay-level (1+ delay-level)
	      buf-size (- buf-size (ash buf-size -2))))
      (if (< delay-level 4)
	  (setq delay-level 4))
      ;; delay_level is 4 for files under around 50k, 7 at 100k, 9 at 200k,
      ;; 11 at 300k, and 12 at 500k, 15 at 1 meg, and 17 at 2 meg.
      (setq delay (/ (* delay-level auto-save-timeout) 4))
      (let ((idle-time (if (or (not (consp last-input-time))
			       (/= (car now) (car last-input-time)))
			   (1+ delay)
			 (- (car (cdr now)) (cdr last-input-time)))))
	(and (> idle-time delay)
	     (do-auto-save))
	(and (> idle-time auto-save-timeout)
	     (> (consing-since-gc) auto-gc-threshold)
	     (garbage-collect)))))
  ;; Look at the itimer that's currently running; if the user has changed
  ;; the value of auto-save-timeout, modify this itimer to have the correct
  ;; restart time.  There will be some latency between when the user changes
  ;; this variable and when it takes effect, but it will happen eventually.
  (let ((self (get-itimer "auto-save")))
    (or self (error "auto-save-itimer can't find itself"))
    (if (and auto-save-timeout (> auto-save-timeout 4))
	(or (= (itimer-restart self) (/ auto-save-timeout 4))
	    (set-itimer-restart self (/ auto-save-timeout 4)))))
  nil)

(defun itimer-init-auto-gc ()
  (or noninteractive ; may be being run from after-init-hook in -batch mode.
      (get-itimer "auto-save")
      ;; the time here is just the first interval; if the user changes it
      ;; later, it will adjust.
      (let ((time (max 2 (/ (or auto-save-timeout 30) 4))))
	(start-itimer "auto-save" 'auto-save-itimer time time))))

(cond (purify-flag
       ;; This file is being preloaded into an emacs about to be dumped.
       ;; So arrange for the auto-save itimer to be started once emacs
       ;; is launched.
       (add-hook 'after-init-hook 'itimer-init-auto-gc))
      (t
       ;; Otherwise, this file is being loaded into a normal, interactive
       ;; emacs.  Start the auto-save timer now.
       (itimer-init-auto-gc)))


;;; itimer-autosave.el ends here