;;; debian-startup.el --- Debian specific emacsen startup code. ;; Copyright (C) 2006 R.Ramkumar ;; Maintainer: R.Ramkumar ;; Keywords: debian ;; This file is submitted for inclusion into the debian release of ;; GNU Emacs. It is released under the same terms, namely the GPL v2 ;; or later. ;; 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., 59 Temple Place - Suite 330, ;; Boston, MA 02111-1307, USA. ;;; Commentary: ;; This file contains startup code needed by all the various flavors ;; of Emacs for a Debian system. This package extends the original ;; package by Rob Browning. Some bits of code have been taken from the ;; original, but the implementation is largely from scratch. The ;; interface provided by this package is compatible with the original ;; with the following additions: ;; ;; * Per-user caching of all startup bits to a single byte-compiled file ;; so that future invocations get speeded up, while not losing the ;; flexibility that the "run-parts with bits for each package" scheme ;; offers. ;; * An optimized `debian-pkg-add-load-path-item' implementation. ;; * Ability for local configuration of packages to be loaded. ;; * Ability to run a part of the local startup procedure before debian ;; startup. Well, isn't Emacs all about flexibility? ;) (defconst debian-startup-site "/etc/emacs/site-debian-startup") (defconst debian-startup-cache-directory "~/.emacs.d") ;; Variables "customizable" from `debian-startup-site' (defvar debian-startup-selection-mode 'disable "Decide how packages to load are decided. This can be one of the two values `disable' or `enable', and affects how the variable `debian-startup-selected-packages' is interpreted. If the former is chosen, `debian-startup-selected-packages' is a black-list of packages to prevent from loading (of all startup bits in the startup directories), while `enable' makes it a white-list of bits to load.") (defvar debian-startup-selected-packages nil "Select packages to white/black-list during loading. A package is essentially the name of a package in the directories passed to `debian-run-directories', without the extension and the leading priority number. How this variable is used for selecting packages is decided by `debian-startup-selection-mode'.") ;; Customization ends here (defvar debian-startup-cache "") (defsubst debian-pkg-add-load-path-item (item) (or (stringp item) (signal 'wrong-type-argument (list 'stringp item))) (let ((ptr load-path) last) (while ptr (and (>= (length (car ptr)) 10) (string-equal (substring (car ptr) 0 10) "/usr/local") (setq last ptr)) (setq ptr (cdr ptr))) (if last (setcdr last (cons item (cdr last))) (setq load-path (cons item load-path))) load-path)) (defsubst xnor (a b) (or (and a b) (not (or a b)))) (defmacro debian-startup-ccheck (var check cache) (list 'setq var (list 'or var (list 'file-newer-than-file-p check cache)))) (eval-and-compile (if (fboundp 'display-warning) (defun debian-startup-error (fmt &rest args) (display-warning 'debian-startup (apply 'format fmt args) :error)) (defun debian-startup-error (fmt &rest args) (apply 'message (concat "Error (debian-startup): " fmt) args)))) (defun debian-run-directories (&rest dirs) (let ((ptr dirs) cur basename package files dirty (scache (concat debian-startup-cache ".el"))) ;; Check if I have changed since the last cache build (debian-startup-ccheck dirty (locate-library "debian-startup") scache) ;; Check if debian-startup-site has changed: this can decide files in cache (debian-startup-ccheck dirty (concat debian-startup-site ".el") scache) (debian-startup-ccheck dirty (concat debian-startup-site ".elc") scache) ;; Safety first! :) (unless (listp debian-startup-selected-packages) (setq debian-startup-selection-mode 'disable) (setq debian-startup-selected-packages nil)) (while ptr ;; Check if something has been added to or deleted from the directory (debian-startup-ccheck dirty (car ptr) scache) (setq cur (directory-files (car ptr) t "^[0-9][0-9].*\\.el$" t)) (while cur (setq basename (file-name-nondirectory (car cur))) (string-match "^[0-9][0-9]\\(.*\\)\\.el$" basename) (when (xnor (eq debian-startup-selection-mode 'enable) (member (match-string 1 basename) debian-startup-selected-packages)) ;; Never trust cache if we have unreadable files. ;; File mode changes cannot be captured by cache validation. (setq dirty (or dirty (not (file-readable-p (car cur))))) ;; Check if the file has changed since the last build (debian-startup-ccheck dirty (car cur) scache) (setq files (cons (cons (car cur) basename) files))) (setq cur (cdr cur))) (setq ptr (cdr ptr))) ;; Sort by basenames leaving the directories intact. ;; Stable sorting, so even if there are duplicates, ;; the (dir . basename) to be loaded stays at the top. (setq files (sort files '(lambda (first second) (string-lessp (cdr first) (cdr second))))) (if (not dirty) ;; We got lucky! Load the cache and be happy!! (let (debian-startup-module) (condition-case error (load debian-startup-cache) (error (debian-startup-error "Unable to load %s: %s" (or debian-startup-module debian-startup-cache) (error-message-string error))))) (message "Startup cache needs to be built. This might take some time, but future invocations would be faster.") (setq ptr "") (setq dirty nil) (with-temp-buffer (insert ";;; This is an automatically generated startup cache file ;;; Do not edit this file\n\n(defvar debian-startup-module)\n") (while files (setq cur (caar files) basename (cdar files)) ;; Weed out duplicates (unless (string-equal ptr basename) ;; Load the file (condition-case error (load cur) (error (debian-startup-error "Unable to load %s: %s" cur (error-message-string error)) (or dirty (debian-startup-error "Stopping cache build")) (setq dirty t) nil)) (unless dirty ;; Write file to cache buffer (insert (format "\n(setq debian-startup-module \"%s\")\n\n" cur)) (condition-case error (insert-file-contents cur) (error (debian-startup-error "Unable to include %s in cache: %s" cur (error-message-string error)) (or dirty (debian-startup-error "Stopping cache build")) (setq dirty t) nil)) (goto-char (point-max))) (setq ptr basename)) (setq files (cdr files))) (unless dirty ;; Write and byte-compile cache for future use (let ((state "write")) (condition-case error (progn (write-region (point-min) (point-max) scache) (setq state "compile") (require 'bytecomp) (byte-compile-file scache)) (error (debian-startup-error "Unable to %s cache: %s" state (error-message-string error)))))))))) (defun debian-startup (flavor) (if (not (boundp 'debian-emacs-flavor)) (defconst debian-emacs-flavor flavor "A symbol representing the particular debian flavor of emacs that's running. Something like 'emacs20, 'xemacs20, etc.") (load debian-startup-site t) (condition-case error (make-directory debian-startup-cache-directory t) (error (debian-startup-error "Unable to create cache directory %s: %s. \ Speeding up of startup by caching might not be possible." debian-startup-cache-directory (error-message-string error)))) (setq debian-startup-cache (expand-file-name (concat debian-startup-cache-directory "/" (symbol-name flavor) "-startup-cache"))) (let ((common-dir "/etc/emacs/site-start.d") (flavor-dir (concat "/etc/" (symbol-name flavor) "/site-start.d"))) (debian-run-directories flavor-dir common-dir)))) (provide 'debian-startup)