;;; ls-lisp.el --- emulate insert-directory completely in Emacs Lisp
;; Copyright (C) 1992, 1994 by Sebastian Kremer <email@example.com>
;; Author: Sebastian Kremer <firstname.lastname@example.org>
;; Keywords: unix
;; This file is part of GNU Emacs.
;; 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.
;; INSTALLATION =======================================================
;; Put this file into your load-path. To use it, load it
;; with (load "ls-lisp").
;; OVERVIEW ===========================================================
;; This file overloads the function insert-directory to implement it
;; directly from Emacs lisp, without running `ls' in a subprocess.
;; It is useful if you cannot afford to fork Emacs on a real memory UNIX,
;; under VMS, or if you don't have the ls program, or if you want
;; different format from what ls offers.
;; This function uses regexps instead of shell
;; wildcards. If you enter regexps remember to double each $ sign.
;; For example, to include files *.el, enter `.*\.el$$',
;; resulting in the regexp `.*\.el$'.
;; RESTRICTIONS =====================================================
;; * many ls switches are ignored, see docstring of `insert-directory'.
;; * Only numeric uid/gid
;; TODO ==============================================================
;; Recognize some more ls switches: R F
(defvar ls-lisp-support-shell-wildcards t
"*Non-nil means file patterns are treated as shell wildcards.
nil means they are treated as Emacs regexps (for backward compatibility).
This variable is checked by \\[insert-directory] only when `ls-lisp.el'
package is used.")
(defun insert-directory (file &optional switches wildcard full-directory-p)
"Insert directory listing for FILE, formatted according to SWITCHES.
Leaves point after the inserted text.
Optional third arg WILDCARD means treat FILE as shell wildcard.
Optional fourth arg FULL-DIRECTORY-P means file is a directory and
switches do not contain `d', so that a full listing is expected.
This version of the function comes from `ls-lisp.el'. It doesn not
run any external programs or shells. It supports ordinary shell
wildcards if `ls-lisp-support-shell-wildcards' variable is non-nil;
otherwise, it interprets wildcards as regular expressions to match
Not all `ls' switches are supported. The switches that work
are: A a c i r S s t u"
(let ((handler (find-file-name-handler file 'insert-directory)))
(funcall handler 'insert-directory file switches
;; Sometimes we get ".../foo*/" as FILE. While the shell and
;; `ls' don't mind, we certainly do, because it makes us think
;; there is no wildcard, only a directory name.
(if (and ls-lisp-support-shell-wildcards
(string-match "[[?*]" file))
(or (not (eq (aref file (1- (length file))) ?/))
(setq file (substring file 0 (1- (length file)))))
(setq wildcard t)))
;; Convert SWITCHES to a list of characters.
(setq switches (append switches nil))
(wildcard-to-regexp (file-name-nondirectory file))
file (file-name-directory file)))
(if (or wildcard
(let* ((dir (file-name-as-directory file))
(default-directory dir);; so that file-attributes works
(file-list (directory-files dir nil wildcard))
;; do all bindings here for speed
(cond ((memq ?A switches)
(ls-lisp-delete-matching "^\\.\\.?$" file-list)))
((not (memq ?a switches))
;; if neither -A nor -a, flush . files
(ls-lisp-delete-matching "^\\." file-list))))
;; file-attributes("~bogus") bombs
(cons x (file-attributes (expand-file-name x)))))
;; inserting the call to directory-files right here
;; seems to stimulate an Emacs bug
;; ILLEGAL DATATYPE (#o37777777727) or #o67
;; ``Total'' line (filled in afterwards).
(insert (if (car-safe file-alist)
;; Shell says ``No match'' if no files match
;; the wildcard; let's say something similar.
"(No match)\ntotal \007\n"))
(ls-lisp-handle-switches file-alist switches))
(setq elt (car file-alist)
file-alist (cdr file-alist)
short (car elt)
attr (cdr elt))
(setq sum (+ sum (nth 7 attr)))
(insert (ls-lisp-format short attr switches now))))
;; Fill in total size of all files:
(search-backward "total \007")
(goto-char (match-end 0))
(insert (format "%d" (if (zerop sum) 0 (1+ (/ sum 1024)))))))
;; if not full-directory-p, FILE *must not* end in /, as
;; file-attributes will not recognize a symlink to a directory
;; must make it a relative filename as ls does:
(setq file (file-name-nondirectory file))
(insert (ls-lisp-format file (file-attributes file) switches
(defun ls-lisp-delete-matching (regexp list)
;; Delete all elements matching REGEXP from LIST, return new list.
;; Should perhaps use setcdr for efficiency.
(or (string-match regexp (car list))
(setq result (cons (car list) result)))
(setq list (cdr list)))
(defun ls-lisp-handle-switches (file-alist switches)
;; FILE-ALIST's elements are (FILE . FILE-ATTRIBUTES).
;; Return new alist sorted according to SWITCHES which is a list of
;; characters. Default sorting is alphabetically.
(cond ((memq ?S switches) ; sorted on size
(lambda (x y)
;; 7th file attribute is file size
;; Make largest file come first
(< (nth 7 (cdr y))
(nth 7 (cdr x))))))
((memq ?t switches) ; sorted on time
(setq index (ls-lisp-time-index switches))
(lambda (x y)
(ls-lisp-time-lessp (nth index (cdr y))
(nth index (cdr x))))))
(t ; sorted alphabetically
(lambda (x y)
(string-lessp (car x)
(if (memq ?r switches) ; reverse sort order
(setq file-alist (nreverse file-alist)))
;; From Roland McGrath. Can use this to sort on time.
(defun ls-lisp-time-lessp (time0 time1)
(let ((hi0 (car time0))
(hi1 (car time1))
(lo0 (car (cdr time0)))
(lo1 (car (cdr time1))))
(or (< hi0 hi1)
(and (= hi0 hi1)
(< lo0 lo1)))))
(defun ls-lisp-format (file-name file-attr switches now)
(let ((file-type (nth 0 file-attr)))
(concat (if (memq ?i switches) ; inode number
(format "%6d " (nth 10 file-attr)))
;; nil is treated like "" in concat
(if (memq ?s switches) ; size in K
(format "%4d " (1+ (/ (nth 7 file-attr) 1024))))
(nth 8 file-attr) ; permission bits
;; numeric uid/gid are more confusing than helpful
;; Emacs should be able to make strings of them.
;; user-login-name and user-full-name could take an
;; optional arg.
(format " %3d %-8s %-8s %8d "
(nth 1 file-attr) ; no. of links
(if (= (user-uid) (nth 2 file-attr))
(int-to-string (nth 2 file-attr))) ; uid
(if (eq system-type 'ms-dos)
"root" ; everything is root on MSDOS.
(int-to-string (nth 3 file-attr))) ; gid
(nth 7 file-attr) ; size in bytes
(ls-lisp-format-time file-attr switches now)
(if (stringp file-type) ; is a symbolic link
(concat " -> " file-type)
(defun ls-lisp-time-index (switches)
;; Return index into file-attributes according to ls SWITCHES.
((memq ?c switches) 6) ; last mode change
((memq ?u switches) 4) ; last access
;; default is last modtime
(defun ls-lisp-format-time (file-attr switches now)
;; Format time string for file with attributes FILE-ATTR according
;; to SWITCHES (a list of ls option letters of which c and u are recognized).
;; Use the same method as `ls' to decide whether to show time-of-day or year,
;; depending on distance between file date and NOW.
(let* ((time (nth (ls-lisp-time-index switches) file-attr))
(diff16 (- (car time) (car now)))
(diff (+ (ash diff16 16) (- (car (cdr time)) (car (cdr now)))))
(past-cutoff (- (* 6 30 24 60 60))) ; 6 30-day months
(future-cutoff (* 60 60))) ; 1 hour
(<= past-cutoff diff) (<= diff future-cutoff)
;; Sanity check in case `diff' computation overflowed.
(<= (1- (ash past-cutoff -16)) diff16)
(<= diff16 (1+ (ash future-cutoff -16))))
"%b %e %H:%M"
"%b %e %Y")
;;; ls-lisp.el ends here