[bpt/emacs.git] / lisp / find-lisp.el

;;; find-lisp.el --- Emulation of find in Emacs Lisp

;; Author:  Peter Breton
;; Created: Fri Mar 26 1999
;; Keywords: unix
;; Time-stamp: <1999-04-19 16:37:01 pbreton>

;; Copyright (C) 1999, 2000 Free Software Foundation, Inc.

;; 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.

;;; Commentary:
;;
;; This is a very generalized form of find; it basically implements a
;; recursive directory descent. The conditions which bound the search
;; are expressed as predicates, and I have not addressed the question
;; of how to wrap up the common chores that find does in a simpler
;; format than writing code for all the various predicates.
;;
;; Some random thoughts are to express simple queries directly with
;; user-level functions, and perhaps use some kind of forms interface
;; for medium-level queries. Really complicated queries can be
;; expressed in Lisp.
;; 

;;; Todo
;;
;; It would be nice if we could sort the results without running the find
;; again. Maybe that could work by storing the original file attributes?

;;; Code:

;; Internal variables

(defvar find-lisp-regexp nil
  "Internal variable.")

(defconst find-lisp-line-indent "  "
  "Indentation for dired file lines.")

(defvar find-lisp-file-predicate nil
  "Predicate for choosing to include files.")

(defvar find-lisp-directory-predicate nil
  "Predicate for choosing to descend into directories.")

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Debugging Code
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(defvar find-lisp-debug-buffer "*Find Lisp Debug*"
  "Buffer for debugging information.")

(defvar find-lisp-debug nil
  "Whether debugging is enabled.")

(defun find-lisp-debug-message (message)
  "Print a debug message MESSAGE in `find-lisp-debug-buffer'."
  (set-buffer (get-buffer-create find-lisp-debug-buffer))
  (goto-char (point-max))
  (insert message "\n"))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Directory and File predicates
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(defun find-lisp-default-directory-predicate  (dir parent)
  "True if DIR is not a dot file, and not a symlink.
PARENT is the parent directory of DIR."
  (and find-lisp-debug
       (find-lisp-debug-message 
	(format "Processing directory %s in %s" dir parent)))
  ;; Skip current and parent directories
  (not (or (string= dir ".")
	   (string= dir "..")
	   ;; Skip directories which are symlinks
	   ;; Easy way to circumvent recursive loops
	   (file-symlink-p dir))))

(defun find-lisp-default-file-predicate  (file dir)
  "True if FILE matches `find-lisp-regexp'.
DIR is the directory containing FILE."
  (and find-lisp-debug
       (find-lisp-debug-message 
	(format "Processing file %s in %s" file dir)))
  (and (not (file-directory-p (expand-file-name file dir)))
       (string-match find-lisp-regexp file)))

(defun find-lisp-file-predicate-is-directory  (file dir)
  "True if FILE is a directory.
Argument DIR is the directory containing FILE."
  (and find-lisp-debug
       (find-lisp-debug-message 
	(format "Processing file %s in %s" file dir)))
  (and (file-directory-p (expand-file-name file dir))
       (not (or (string= file ".")
		(string= file "..")))))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Find functions
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(defun find-lisp-find-files (directory regexp)
  "Find files in DIRECTORY which match REGEXP."
  (let ((file-predicate      'find-lisp-default-file-predicate)
	(directory-predicate 'find-lisp-default-directory-predicate)
	(find-lisp-regexp regexp)
	)
    (find-lisp-find-files-internal 
     directory 
     file-predicate
     directory-predicate)))

;; Workhorse function
(defun find-lisp-find-files-internal (directory file-predicate 
						directory-predicate)
  "Find files under DIRECTORY which satisfy FILE-PREDICATE.
FILE-PREDICATE is a function which takes two arguments: the file and its 
directory.

DIRECTORY-PREDICATE is used to decide whether to descend into directories.
It is a function which takes two arguments, the directory and its parent."
  (let (results sub-results)
    (mapcar
     (function
      (lambda(file)
	(let ((fullname (expand-file-name file directory)))
	  (and (file-readable-p (expand-file-name file directory))
	       (progn
		 ;; If a directory, check it we should descend into it
		 (and (file-directory-p fullname)
		      (funcall directory-predicate file directory)
		      (progn
			(setq sub-results
			      (find-lisp-find-files-internal
			       fullname 
			       file-predicate
			       directory-predicate))
			(if results 
			    (nconc results sub-results)
			  (setq results sub-results))))
		 ;; For all files and directories, call the file predicate
		 (and (funcall file-predicate file directory)
		      (if results 
			  (nconc results (list fullname))
			(setq results (list fullname))))
		 )))))
     (directory-files directory nil nil t))
    results))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Find-dired all in Lisp
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(defun find-lisp-find-dired (dir regexp)
  "Find files in DIR, matching REGEXP."
  (interactive "DFind files in directory: \nsMatching regexp: ")
  (let ((find-lisp-regexp regexp))
    (find-lisp-find-dired-internal
     dir
     'find-lisp-default-file-predicate
     'find-lisp-default-directory-predicate
     "*Find Lisp Dired*")))

;; Just the subdirectories
(defun find-lisp-find-dired-subdirectories (dir)
  "Find all subdirectories of DIR."
  (interactive "DFind subdirectories of directory: ")
  (find-lisp-find-dired-internal
   dir
   'find-lisp-file-predicate-is-directory
   'find-lisp-default-directory-predicate
   "*Find Lisp Dired Subdirectories*"))

;; Most of this is lifted from find-dired.el
;; 
(defun find-lisp-find-dired-internal (dir file-predicate 
					  directory-predicate buffer-name)
  "Run find (Lisp version) and go into Dired mode on a buffer of the output."
  (let ((dired-buffers dired-buffers)
	buf
	(regexp find-lisp-regexp))
    ;; Expand DIR ("" means default-directory), and make sure it has a
    ;; trailing slash.
    (setq dir (abbreviate-file-name
	       (file-name-as-directory (expand-file-name dir))))
    ;; Check that it's really a directory.
    (or (file-directory-p dir)
	(error "find-dired needs a directory: %s" dir))
    (or 
     (and (buffer-name)
	  (string= buffer-name (buffer-name)))
	(switch-to-buffer (setq buf (get-buffer-create buffer-name))))
    (widen)
    (kill-all-local-variables)
    (setq buffer-read-only nil)
    (erase-buffer)
    (setq default-directory dir)
    (dired-mode dir)

    (use-local-map (append (make-sparse-keymap) (current-local-map)))

    (make-local-variable 'find-lisp-file-predicate)
    (setq find-lisp-file-predicate file-predicate)
    (make-local-variable 'find-lisp-directory-predicate)
    (setq find-lisp-directory-predicate directory-predicate)
    (make-local-variable 'find-lisp-regexp)
    (setq find-lisp-regexp regexp)

    (make-local-variable 'revert-buffer-function)
    (setq revert-buffer-function
	  (function
	   (lambda(ignore1 ignore2)
	     (find-lisp-insert-directory 
	      default-directory
	      find-lisp-file-predicate
	      find-lisp-directory-predicate
	      'ignore)
	     )
	   ))

    ;; Set subdir-alist so that Tree Dired will work:
    (if (fboundp 'dired-simple-subdir-alist)
	;; will work even with nested dired format (dired-nstd.el,v 1.15
	;; and later)
	(dired-simple-subdir-alist)
      ;; else we have an ancient tree dired (or classic dired, where
      ;; this does no harm) 
      (set (make-local-variable 'dired-subdir-alist)
	   (list (cons default-directory (point-min-marker)))))
    (find-lisp-insert-directory 
     dir file-predicate directory-predicate 'ignore)
    (goto-char (point-min))
    (dired-goto-next-file)))

(defun find-lisp-insert-directory  (dir 
				    file-predicate 
				    directory-predicate 
				    sort-function)
  "Insert the results of `find-lisp-find-files' in the current buffer."
  (let ((buffer-read-only nil)
	(files (find-lisp-find-files-internal 
		dir 
		file-predicate 
		directory-predicate))
	(len (length dir)))
    (erase-buffer)
    ;; Subdir headlerline must come first because the first marker in
    ;; subdir-alist points there.
    (insert find-lisp-line-indent dir ":\n")
    ;; Make second line a ``find'' line in analogy to the ``total'' or
    ;; ``wildcard'' line. 
    ;;
    ;; No analog for find-lisp?
    (insert find-lisp-line-indent "\n")
    ;; Run the find function
    (mapcar
     (function
      (lambda(file)
	(find-lisp-find-dired-insert-file	 
	 (substring file len)
	 (current-buffer))))
     (sort files 'string-lessp))
    ;; FIXME: Sort function is ignored for now
    ;; (funcall sort-function files))
    (goto-char (point-min))
    (dired-goto-next-file)))

(defun find-lisp-find-dired-filter (regexp)
  "Change the filter on a find-lisp-find-dired buffer to REGEXP."
  (interactive "sSet filter to regexp: ")
  (setq find-lisp-regexp regexp)
  (revert-buffer))

(defun find-lisp-find-dired-insert-file (file buffer)
  (set-buffer buffer)
  (insert find-lisp-line-indent 
	  (find-lisp-format file (file-attributes file) (list "")
			  (current-time))))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Lifted from ls-lisp. We don't want to require it, because that
;; would alter the insert-directory function.
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(defun find-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))
			(user-login-name)
		      (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
		    )
	    (find-lisp-format-time file-attr switches now)
	    " "
	    file-name
	    (if (stringp file-type)	; is a symbolic link
		(concat " -> " file-type)
	      "")
	    "\n")))

(defun find-lisp-time-index (switches)
  ;; Return index into file-attributes according to ls SWITCHES.
  (cond
   ((memq ?c switches) 6)		; last mode change
   ((memq ?u switches) 4)		; last access
   ;; default is last modtime
   (t 5)))

(defun find-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 (find-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
    (format-time-string
     (if (and
	  (<= 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")
     time)))

(provide 'find-lisp)

;;; find-lisp.el ends here

;; Local Variables:
;; autocompile: t
;; End:
Commit	Line	Data
6344985d GM	1	;;; find-lisp.el --- Emulation of find in Emacs Lisp
	2
	3	;; Author: Peter Breton
	4	;; Created: Fri Mar 26 1999
	5	;; Keywords: unix
	6	;; Time-stamp: <1999-04-19 16:37:01 pbreton>
	7
	8	;; Copyright (C) 1999, 2000 Free Software Foundation, Inc.
	9
	10	;; This file is part of GNU Emacs.
	11
	12	;; GNU Emacs is free software; you can redistribute it and/or modify
	13	;; it under the terms of the GNU General Public License as published by
	14	;; the Free Software Foundation; either version 2, or (at your option)
	15	;; any later version.
	16
	17	;; GNU Emacs is distributed in the hope that it will be useful,
	18	;; but WITHOUT ANY WARRANTY; without even the implied warranty of
	19	;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	20	;; GNU General Public License for more details.
	21
	22	;; You should have received a copy of the GNU General Public License
	23	;; along with GNU Emacs; see the file COPYING. If not, write to the
	24	;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
	25	;; Boston, MA 02111-1307, USA.
	26
	27	;;; Commentary:
	28	;;
	29	;; This is a very generalized form of find; it basically implements a
	30	;; recursive directory descent. The conditions which bound the search
	31	;; are expressed as predicates, and I have not addressed the question
	32	;; of how to wrap up the common chores that find does in a simpler
	33	;; format than writing code for all the various predicates.
	34	;;
	35	;; Some random thoughts are to express simple queries directly with
	36	;; user-level functions, and perhaps use some kind of forms interface
	37	;; for medium-level queries. Really complicated queries can be
	38	;; expressed in Lisp.
	39	;;
	40
	41	;;; Todo
	42	;;
	43	;; It would be nice if we could sort the results without running the find
	44	;; again. Maybe that could work by storing the original file attributes?
	45
	46	;;; Code:
	47
	48	;; Internal variables
	49
	50	(defvar find-lisp-regexp nil
	51	"Internal variable.")
	52
	53	(defconst find-lisp-line-indent " "
	54	"Indentation for dired file lines.")
	55
	56	(defvar find-lisp-file-predicate nil
	57	"Predicate for choosing to include files.")
	58
	59	(defvar find-lisp-directory-predicate nil
	60	"Predicate for choosing to descend into directories.")
	61
	62	;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
	63	;; Debugging Code
	64	;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
65
66	(defvar find-lisp-debug-buffer "Find Lisp Debug"
67	"Buffer for debugging information.")
68
69	(defvar find-lisp-debug nil
70	"Whether debugging is enabled.")
71
72	(defun find-lisp-debug-message (message)
73	"Print a debug message MESSAGE in `find-lisp-debug-buffer'."
74	(set-buffer (get-buffer-create find-lisp-debug-buffer))
75	(goto-char (point-max))
76	(insert message "\n"))
77
78	;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
79	;; Directory and File predicates
80	;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
81
82	(defun find-lisp-default-directory-predicate (dir parent)
83	"True if DIR is not a dot file, and not a symlink.
84	PARENT is the parent directory of DIR."
85	(and find-lisp-debug
86	(find-lisp-debug-message
87	(format "Processing directory %s in %s" dir parent)))
88	;; Skip current and parent directories
89	(not (or (string= dir ".")
90	(string= dir "..")
91	;; Skip directories which are symlinks
92	;; Easy way to circumvent recursive loops
93	(file-symlink-p dir))))
94
95	(defun find-lisp-default-file-predicate (file dir)
96	"True if FILE matches `find-lisp-regexp'.
97	DIR is the directory containing FILE."
98	(and find-lisp-debug
99	(find-lisp-debug-message
100	(format "Processing file %s in %s" file dir)))
101	(and (not (file-directory-p (expand-file-name file dir)))
102	(string-match find-lisp-regexp file)))
103
104	(defun find-lisp-file-predicate-is-directory (file dir)
105	"True if FILE is a directory.
106	Argument DIR is the directory containing FILE."
107	(and find-lisp-debug
108	(find-lisp-debug-message
109	(format "Processing file %s in %s" file dir)))
110	(and (file-directory-p (expand-file-name file dir))
111	(not (or (string= file ".")
112	(string= file "..")))))
113
114	;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
115	;; Find functions
116	;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
117
118	(defun find-lisp-find-files (directory regexp)
119	"Find files in DIRECTORY which match REGEXP."
120	(let ((file-predicate 'find-lisp-default-file-predicate)
121	(directory-predicate 'find-lisp-default-directory-predicate)
122	(find-lisp-regexp regexp)
123	)
124	(find-lisp-find-files-internal
125	directory
126	file-predicate
127	directory-predicate)))
128
129	;; Workhorse function
130	(defun find-lisp-find-files-internal (directory file-predicate
131	directory-predicate)
132	"Find files under DIRECTORY which satisfy FILE-PREDICATE.
133	FILE-PREDICATE is a function which takes two arguments: the file and its
134	directory.
135
136	DIRECTORY-PREDICATE is used to decide whether to descend into directories.
137	It is a function which takes two arguments, the directory and its parent."
138	(let (results sub-results)
139	(mapcar
140	(function
141	(lambda(file)
142	(let ((fullname (expand-file-name file directory)))
143	(and (file-readable-p (expand-file-name file directory))
144	(progn
145	;; If a directory, check it we should descend into it
146	(and (file-directory-p fullname)
147	(funcall directory-predicate file directory)
148	(progn
149	(setq sub-results
150	(find-lisp-find-files-internal
151	fullname
152	file-predicate
153	directory-predicate))
154	(if results
155	(nconc results sub-results)
156	(setq results sub-results))))
157	;; For all files and directories, call the file predicate
158	(and (funcall file-predicate file directory)
159	(if results
160	(nconc results (list fullname))
161	(setq results (list fullname))))
162	)))))
163	(directory-files directory nil nil t))
164	results))
165
166	;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
167	;; Find-dired all in Lisp
168	;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
169
170	(defun find-lisp-find-dired (dir regexp)
171	"Find files in DIR, matching REGEXP."
172	(interactive "DFind files in directory: \nsMatching regexp: ")
173	(let ((find-lisp-regexp regexp))
174	(find-lisp-find-dired-internal
175	dir
176	'find-lisp-default-file-predicate
177	'find-lisp-default-directory-predicate
178	"Find Lisp Dired")))
179
180	;; Just the subdirectories
181	(defun find-lisp-find-dired-subdirectories (dir)
182	"Find all subdirectories of DIR."
183	(interactive "DFind subdirectories of directory: ")
184	(find-lisp-find-dired-internal
185	dir
186	'find-lisp-file-predicate-is-directory
187	'find-lisp-default-directory-predicate
188	"Find Lisp Dired Subdirectories"))
189
190	;; Most of this is lifted from find-dired.el
191	;;
192	(defun find-lisp-find-dired-internal (dir file-predicate
193	directory-predicate buffer-name)
194	"Run find (Lisp version) and go into Dired mode on a buffer of the output."
195	(let ((dired-buffers dired-buffers)
196	buf
197	(regexp find-lisp-regexp))
198	;; Expand DIR ("" means default-directory), and make sure it has a
199	;; trailing slash.
200	(setq dir (abbreviate-file-name
201	(file-name-as-directory (expand-file-name dir))))
202	;; Check that it's really a directory.
203	(or (file-directory-p dir)
204	(error "find-dired needs a directory: %s" dir))
205	(or
206	(and (buffer-name)
207	(string= buffer-name (buffer-name)))
208	(switch-to-buffer (setq buf (get-buffer-create buffer-name))))
209	(widen)
210	(kill-all-local-variables)
211	(setq buffer-read-only nil)
212	(erase-buffer)
213	(setq default-directory dir)
214	(dired-mode dir)
215
216	(use-local-map (append (make-sparse-keymap) (current-local-map)))
217
218	(make-local-variable 'find-lisp-file-predicate)
219	(setq find-lisp-file-predicate file-predicate)
220	(make-local-variable 'find-lisp-directory-predicate)
221	(setq find-lisp-directory-predicate directory-predicate)
222	(make-local-variable 'find-lisp-regexp)
223	(setq find-lisp-regexp regexp)
224
225	(make-local-variable 'revert-buffer-function)
226	(setq revert-buffer-function
227	(function
228	(lambda(ignore1 ignore2)
229	(find-lisp-insert-directory
230	default-directory
231	find-lisp-file-predicate
232	find-lisp-directory-predicate
233	'ignore)
234	)
235	))
236
237	;; Set subdir-alist so that Tree Dired will work:
238	(if (fboundp 'dired-simple-subdir-alist)
239	;; will work even with nested dired format (dired-nstd.el,v 1.15
240	;; and later)
241	(dired-simple-subdir-alist)
242	;; else we have an ancient tree dired (or classic dired, where
243	;; this does no harm)
244	(set (make-local-variable 'dired-subdir-alist)
245	(list (cons default-directory (point-min-marker)))))
246	(find-lisp-insert-directory
247	dir file-predicate directory-predicate 'ignore)
248	(goto-char (point-min))
249	(dired-goto-next-file)))
250
251	(defun find-lisp-insert-directory (dir
252	file-predicate
253	directory-predicate
254	sort-function)
255	"Insert the results of `find-lisp-find-files' in the current buffer."
256	(let ((buffer-read-only nil)
257	(files (find-lisp-find-files-internal
258	dir
259	file-predicate
260	directory-predicate))
261	(len (length dir)))
262	(erase-buffer)
263	;; Subdir headlerline must come first because the first marker in
264	;; subdir-alist points there.
265	(insert find-lisp-line-indent dir ":\n")
266	;; Make second line a ``find'' line in analogy to the ``total'' or
267	;; ``wildcard'' line.
268	;;
269	;; No analog for find-lisp?
270	(insert find-lisp-line-indent "\n")
271	;; Run the find function
272	(mapcar
273	(function
274	(lambda(file)
275	(find-lisp-find-dired-insert-file
276	(substring file len)
277	(current-buffer))))
278	(sort files 'string-lessp))
279	;; FIXME: Sort function is ignored for now
280	;; (funcall sort-function files))
281	(goto-char (point-min))
282	(dired-goto-next-file)))
283
284	(defun find-lisp-find-dired-filter (regexp)
285	"Change the filter on a find-lisp-find-dired buffer to REGEXP."
286	(interactive "sSet filter to regexp: ")
287	(setq find-lisp-regexp regexp)
288	(revert-buffer))
289
290	(defun find-lisp-find-dired-insert-file (file buffer)
291	(set-buffer buffer)
292	(insert find-lisp-line-indent
293	(find-lisp-format file (file-attributes file) (list "")
294	(current-time))))
295
296	;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
297	;; Lifted from ls-lisp. We don't want to require it, because that
298	;; would alter the insert-directory function.
299	;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
300
301	(defun find-lisp-format (file-name file-attr switches now)
302	(let ((file-type (nth 0 file-attr)))
303	(concat (if (memq ?i switches) ; inode number
304	(format "%6d " (nth 10 file-attr)))
305	;; nil is treated like "" in concat
306	(if (memq ?s switches) ; size in K
307	(format "%4d " (1+ (/ (nth 7 file-attr) 1024))))
308	(nth 8 file-attr) ; permission bits
309	;; numeric uid/gid are more confusing than helpful
310	;; Emacs should be able to make strings of them.
311	;; user-login-name and user-full-name could take an
312	;; optional arg.
313	(format " %3d %-8s %-8s %8d "
314	(nth 1 file-attr) ; no. of links
315	(if (= (user-uid) (nth 2 file-attr))
316	(user-login-name)
317	(int-to-string (nth 2 file-attr))) ; uid
318	(if (eq system-type 'ms-dos)
319	"root" ; everything is root on MSDOS.
320	(int-to-string (nth 3 file-attr))) ; gid
321	(nth 7 file-attr) ; size in bytes
322	)
323	(find-lisp-format-time file-attr switches now)
324	" "
325	file-name
326	(if (stringp file-type) ; is a symbolic link
327	(concat " -> " file-type)
328	"")
329	"\n")))
330
331	(defun find-lisp-time-index (switches)
332	;; Return index into file-attributes according to ls SWITCHES.
333	(cond
334	((memq ?c switches) 6) ; last mode change
335	((memq ?u switches) 4) ; last access
336	;; default is last modtime
337	(t 5)))
338
339	(defun find-lisp-format-time (file-attr switches now)
340	;; Format time string for file with attributes FILE-ATTR according
341	;; to SWITCHES (a list of ls option letters of which c and u are recognized).
342	;; Use the same method as `ls' to decide whether to show time-of-day or year,
343	;; depending on distance between file date and NOW.
344	(let* ((time (nth (find-lisp-time-index switches) file-attr))
345	(diff16 (- (car time) (car now)))
346	(diff (+ (ash diff16 16) (- (car (cdr time)) (car (cdr now)))))
347	(past-cutoff (- (* 6 30 24 60 60))) ; 6 30-day months
348	(future-cutoff (* 60 60))) ; 1 hour
349	(format-time-string
350	(if (and
351	(<= past-cutoff diff) (<= diff future-cutoff)
352	;; Sanity check in case `diff' computation overflowed.
353	(<= (1- (ash past-cutoff -16)) diff16)
354	(<= diff16 (1+ (ash future-cutoff -16))))
355	"%b %e %H:%M"
356	"%b %e %Y")
357	time)))
358
359	(provide 'find-lisp)
360
361	;;; find-lisp.el ends here
362
363	;; Local Variables:
364	;; autocompile: t
365	;; End: