locate.el

[Luc Teirlinck]

Below is my latest and probably final patch for locate.el.

The main visible changes is that the header now looks like:

  /:
 Matches for compdir:

Having `  /:' as first line is absolutely necessary when having
inserted subdirectories.  Otherwise, dired-subdir-alist can get
corrupted and then things _really_ go wrong.

The patch below also corrects a problem unrelated to subdirectories.
Currently, locate.el has _two_ `;;; Commentary' sections.  This does
not work.  Currently the only documentation one gets by following
links after `C-h p' are some MS Windows specific technical details,
whereas the more general stuff gets ignored.  I hardly believe that
this is intentional.  The patch below combines both `Commentary'
sections into one and puts the OS specific stuff at the end.

I will finally commit after waiting still a while to see if there are
any objections to the final version.

===File ~/locate-diff=======================================
*** locate.el   20 May 2004 17:14:36 -0500      1.22
--- locate.el   02 Jun 2004 21:18:19 -0500      
***************
*** 24,65 ****
  
  ;;; Commentary:
  
! ;; Search a database of files and use dired commands on
! ;; the result.
! ;;
! 
! ;;;;; Building a database of files ;;;;;;;;;
! ;;
! ;; You can create a simple files database with a port of the Unix find command
! ;; and one of the various Windows NT various scheduling utilities,
! ;; for example the AT command from the NT Resource Kit, WinCron which is
! ;; included with Microsoft FrontPage, or the shareware NTCron program.
! ;;
! ;; To set up a function which searches the files database, do something
! ;; like this:
! ;;
! ;; (defvar locate-fcodes-file       "c:/users/peter/fcodes")
! ;; (defvar locate-make-command-line 'nt-locate-make-command-line)
! ;;
! ;; (defun nt-locate-make-command-line (arg)
! ;;  (list "grep" "-i" arg locate-fcodes-file))
! ;;
! ;;;;;;;; ADVICE For dired-make-relative: ;;;;;;;;;
! ;;
! ;; For certain dired commands to work right, you should also include the
! ;; following in your _emacs/.emacs:
! ;;
! ;; (defadvice dired-make-relative (before set-no-error activate)
! ;;   "For locate mode and Windows, don't return errors"
! ;;   (if (and (eq   major-mode  'locate-mode)
! ;;       (memq system-type (list 'windows-nt 'ms-dos)))
! ;;       (ad-set-arg 2 t)
! ;;     ))
! ;;
! ;; Otherwise, `dired-make-relative' will give error messages like
! ;; "FILENAME: not in directory tree growing at /"
! 
! ;;; Commentary:
  ;;
  ;; Locate.el provides an interface to a program which searches a
  ;; database of file names. By default, this program is the GNU locate
--- 24,30 ----
  
  ;;; Commentary:
  
! ;; Search a database of files and use dired commands on the result.
  ;;
  ;; Locate.el provides an interface to a program which searches a
  ;; database of file names. By default, this program is the GNU locate
***************
*** 109,114 ****
--- 74,111 ----
  ;; regular expression; this is often useful to constrain a big search.
  ;;
  
+ ;;;;; Building a database of files ;;;;;;;;;
+ ;;
+ ;; You can create a simple files database with a port of the Unix find command
+ ;; and one of the various Windows NT various scheduling utilities,
+ ;; for example the AT command from the NT Resource Kit, WinCron which is
+ ;; included with Microsoft FrontPage, or the shareware NTCron program.
+ ;;
+ ;; To set up a function which searches the files database, do something
+ ;; like this:
+ ;;
+ ;; (defvar locate-fcodes-file       "c:/users/peter/fcodes")
+ ;; (defvar locate-make-command-line 'nt-locate-make-command-line)
+ ;;
+ ;; (defun nt-locate-make-command-line (arg)
+ ;;  (list "grep" "-i" arg locate-fcodes-file))
+ ;;
+ ;;;;;;;; ADVICE For dired-make-relative: ;;;;;;;;;
+ ;;
+ ;; For certain dired commands to work right, you should also include the
+ ;; following in your _emacs/.emacs:
+ ;;
+ ;; (defadvice dired-make-relative (before set-no-error activate)
+ ;;   "For locate mode and Windows, don't return errors"
+ ;;   (if (and (eq   major-mode  'locate-mode)
+ ;;       (memq system-type (list 'windows-nt 'ms-dos)))
+ ;;       (ad-set-arg 2 t)
+ ;;     ))
+ ;;
+ ;; Otherwise, `dired-make-relative' will give error messages like
+ ;; "FILENAME: not in directory tree growing at /"
+ 
+ 
  ;;; Code:
  
  (eval-when-compile
***************
*** 223,246 ****
      (save-window-excursion
        (set-buffer (get-buffer-create locate-buffer-name))
        (locate-mode)
!       (erase-buffer)
  
!       (setq locate-current-filter filter)
  
!       (if run-locate-command
!         (shell-command search-string locate-buffer-name)
!       (apply 'call-process locate-cmd nil t nil locate-cmd-args))
  
!       (and filter
!         (locate-filter-output filter))
  
!       (locate-do-setup search-string)
!       )
      (and (not (string-equal (buffer-name) locate-buffer-name))
        (switch-to-buffer-other-window locate-buffer-name))
  
      (run-hooks 'dired-mode-hook)
!     (dired-next-line 2)                       ;move to first matching file.
      (run-hooks 'locate-post-command-hook)
      )
    )
--- 220,244 ----
      (save-window-excursion
        (set-buffer (get-buffer-create locate-buffer-name))
        (locate-mode)
!       (let ((inhibit-read-only t))
!       (erase-buffer)
  
!       (setq locate-current-filter filter)
  
!       (if run-locate-command
!           (shell-command search-string locate-buffer-name)
!         (apply 'call-process locate-cmd nil t nil locate-cmd-args))
  
!       (and filter
!            (locate-filter-output filter))
  
!       (locate-do-setup search-string)
!       ))
      (and (not (string-equal (buffer-name) locate-buffer-name))
        (switch-to-buffer-other-window locate-buffer-name))
  
      (run-hooks 'dired-mode-hook)
!     (dired-next-line 3)                       ;move to first matching file.
      (run-hooks 'locate-post-command-hook)
      )
    )
***************
*** 281,287 ****
     (define-key locate-mode-map [menu-bar mark directories] 'undefined)
     (define-key locate-mode-map [menu-bar mark symlinks]    'undefined)
  
!    (define-key locate-mode-map [mouse-2]   'locate-mouse-view-file)
     (define-key locate-mode-map "\C-c\C-t"  'locate-tags)
  
     (define-key locate-mode-map "U"       'dired-unmark-all-files)
--- 279,285 ----
     (define-key locate-mode-map [menu-bar mark directories] 'undefined)
     (define-key locate-mode-map [menu-bar mark symlinks]    'undefined)
  
!    (define-key locate-mode-map [M-mouse-2]   'locate-mouse-view-file)
     (define-key locate-mode-map "\C-c\C-t"  'locate-tags)
  
     (define-key locate-mode-map "U"       'dired-unmark-all-files)
***************
*** 318,329 ****
         (not (eq lineno 2))
         (buffer-substring (elt pos 0) (elt pos 1)))))
  
  (defun locate-mouse-view-file (event)
    "In Locate mode, view a file, using the mouse."
    (interactive "@e")
    (save-excursion
      (goto-char (posn-point (event-start event)))
!     (view-file (locate-get-filename))))
  
  ;; Define a mode for locate
  ;; Default directory is set to "/" so that dired commands, which
--- 316,339 ----
         (not (eq lineno 2))
         (buffer-substring (elt pos 0) (elt pos 1)))))
  
+ (defun locate-main-listing-line-p ()
+   "Return t if current line contains a file name listed by locate.
+ This function returns nil if the current line either contains no
+ file name or is inside a subdirectory."
+   (save-excursion
+     (forward-line 0)
+     (looking-at (concat "."
+                       (make-string (1- locate-filename-indentation) ?\ )
+                       "\\(/\\|[A-Za-z]:\\)"))))
+ 
  (defun locate-mouse-view-file (event)
    "In Locate mode, view a file, using the mouse."
    (interactive "@e")
    (save-excursion
      (goto-char (posn-point (event-start event)))
!     (if (locate-main-listing-line-p)
!       (view-file (locate-get-filename))
!       (message "This command only works inside main listing."))))
  
  ;; Define a mode for locate
  ;; Default directory is set to "/" so that dired commands, which
***************
*** 333,362 ****
  In that buffer, you can use almost all the usual dired bindings.
  \\[locate-find-directory] visits the directory of the file on the current 
line.
  
  \\{locate-mode-map}"
    (kill-all-local-variables)
!   ;; Avoid clobbering this variables
    (make-local-variable 'dired-subdir-alist)
    (use-local-map             locate-mode-map)
    (setq major-mode          'locate-mode
          mode-name           "Locate"
!         default-directory   "/")
    (dired-alist-add-1 default-directory (point-min-marker))
    (make-local-variable 'dired-move-to-filename-regexp)
    ;; This should support both Unix and Windoze style names
    (setq dired-move-to-filename-regexp
!       (concat "."
                (make-string (1- locate-filename-indentation) ?\ )
!               "\\(/\\|[A-Za-z]:\\)"))
    (make-local-variable 'dired-actual-switches)
    (setq dired-actual-switches "")
    (make-local-variable 'dired-permission-flags-regexp)
    (setq dired-permission-flags-regexp
        (concat "^.\\("
                (make-string (1- locate-filename-indentation) ?\ )
!               "\\)"))
    (make-local-variable 'revert-buffer-function)
    (setq revert-buffer-function 'locate-update)
    (run-hooks 'locate-mode-hook))
  
  (defun locate-do-setup (search-string)
--- 343,396 ----
  In that buffer, you can use almost all the usual dired bindings.
  \\[locate-find-directory] visits the directory of the file on the current 
line.
  
+ As usual, you can insert subdirectories using \
+ \\[dired-maybe-insert-subdir] and update them
+ using \
+ \\[dired-do-redisplay].  However, \\[dired-do-redisplay]. only works on \
+ subdirectory header lines.
+ At other places, it may cause strange results.  These can be undone
+ using \\[dired-undo].  Specific `locate-mode' commands, such as \
+ \\[locate-find-directory],
+ do not work in subdirectories.  Reverting the buffer using
+ \\[revert-buffer] deletes all inserted subdirectories.
+ 
+ Operating on listed files works, but does not always
+ automatically update the buffer as in ordinary Dired.
+ This is true both for the main listing and for subdirectories.
+ 
  \\{locate-mode-map}"
+   ;; Not to be called interactively.
    (kill-all-local-variables)
!   ;; Avoid clobbering this variable
    (make-local-variable 'dired-subdir-alist)
    (use-local-map             locate-mode-map)
    (setq major-mode          'locate-mode
          mode-name           "Locate"
!         default-directory   "/"
!       buffer-read-only    t
!       selective-display   t)
    (dired-alist-add-1 default-directory (point-min-marker))
+   (set (make-local-variable 'dired-directory) "/")
+   (set (make-local-variable 'dired-subdir-switches) "-al")
+   (set (make-local-variable 'dired-switches-alist) nil)
    (make-local-variable 'dired-move-to-filename-regexp)
    ;; This should support both Unix and Windoze style names
    (setq dired-move-to-filename-regexp
!       (concat "^."
                (make-string (1- locate-filename-indentation) ?\ )
!               "\\(/\\|[A-Za-z]:\\)\\|"
!               (default-value 'dired-move-to-filename-regexp)))
    (make-local-variable 'dired-actual-switches)
    (setq dired-actual-switches "")
    (make-local-variable 'dired-permission-flags-regexp)
    (setq dired-permission-flags-regexp
        (concat "^.\\("
                (make-string (1- locate-filename-indentation) ?\ )
!               "\\)\\|"
!               (default-value 'dired-permission-flags-regexp)))
    (make-local-variable 'revert-buffer-function)
    (setq revert-buffer-function 'locate-update)
+   (set (make-local-variable 'page-delimiter) "\n\n")
    (run-hooks 'locate-mode-hook))
  
  (defun locate-do-setup (search-string)
***************
*** 386,392 ****
        (dired-insert-set-properties (elt pos 0) (elt pos 1)))))
  
  (defun locate-insert-header (search-string)
!   (let ((locate-format-string "Matches for %s")
        (locate-regexp-match
         (concat " *Matches for \\(" (regexp-quote search-string) "\\)"))
        (locate-format-args (list search-string))
--- 420,429 ----
        (dired-insert-set-properties (elt pos 0) (elt pos 1)))))
  
  (defun locate-insert-header (search-string)
!   ;; There needs to be a space before `Matches, because otherwise,
!   ;; `*!" would erase the `M'.  We can not use two spaces, or the line
!   ;; would mistakenly fit `dired-subdir-regexp'.
!   (let ((locate-format-string "  /:\n Matches for %s")
        (locate-regexp-match
         (concat " *Matches for \\(" (regexp-quote search-string) "\\)"))
        (locate-format-args (list search-string))
***************
*** 424,429 ****
--- 461,467 ----
  
      (save-excursion
        (goto-char (point-min))
+       (forward-line 1)
        (if (not (looking-at locate-regexp-match))
          nil
        (add-text-properties (match-beginning 1) (match-end 1)
***************
*** 439,447 ****
  (defun locate-tags ()
    "Visit a tags table in `*Locate*' mode."
    (interactive)
!   (let ((tags-table (locate-get-filename)))
!     (and (y-or-n-p (format "Visit tags table %s? " tags-table))
!        (visit-tags-table tags-table))))
  
  ;; From Stephen Eglen <address@hidden>
  (defun locate-update (ignore1 ignore2)
--- 477,487 ----
  (defun locate-tags ()
    "Visit a tags table in `*Locate*' mode."
    (interactive)
!   (if (locate-main-listing-line-p)
!       (let ((tags-table (locate-get-filename)))
!       (and (y-or-n-p (format "Visit tags table %s? " tags-table))
!            (visit-tags-table tags-table)))
!     (message "This command only works inside main listing.")))
  
  ;; From Stephen Eglen <address@hidden>
  (defun locate-update (ignore1 ignore2)
***************
*** 460,471 ****
  (defun locate-find-directory ()
    "Visit the directory of the file mentioned on this line."
    (interactive)
!   (let ((directory-name (locate-get-dirname)))
!     (if (file-directory-p directory-name)
!       (find-file directory-name)
!       (if (file-symlink-p directory-name)
!         (error "Directory is a symlink to a nonexistent target")
!       (error "Directory no longer exists; run `updatedb' to update 
database")))))
  
  (defun locate-find-directory-other-window ()
    "Visit the directory of the file named on this line in other window."
--- 500,513 ----
  (defun locate-find-directory ()
    "Visit the directory of the file mentioned on this line."
    (interactive)
!   (if (locate-main-listing-line-p)
!       (let ((directory-name (locate-get-dirname)))
!       (if (file-directory-p directory-name)
!           (find-file directory-name)
!         (if (file-symlink-p directory-name)
!             (error "Directory is a symlink to a nonexistent target")
!           (error "Directory no longer exists; run `updatedb' to update 
database"))))
!     (message "This command only works inside main listing.")))
  
  (defun locate-find-directory-other-window ()
    "Visit the directory of the file named on this line in other window."
============================================================