;;; etags.el --- etags facility for Emacs
-
-;; Copyright (C) 1985, 1986, 1988, 1989, 1992, 1993, 1994, 1995
+;; Copyright (C) 1985, 1986, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1998
;; Free Software Foundation, Inc.
;; Author: Roland McGrath <roland@gnu.ai.mit.edu>
;;; Code:
+(require 'ring)
+
;;;###autoload
(defvar tags-file-name nil
"*File name of tags table.
;; Make M-x set-variable tags-file-name like M-x visit-tags-table.
;;;###autoload (put 'tags-file-name 'variable-interactive "fVisit tags table: ")
+(defgroup etags nil "Tags tables"
+ :group 'tools)
+
;;;###autoload
;; Use `visit-tags-table-buffer' to cycle through tags tables in this list.
-(defvar tags-table-list nil
+(defcustom tags-table-list nil
"*List of file names of tags tables to search.
An element that is a directory means the file \"TAGS\" in that directory.
To switch to a new list of tags tables, setting this variable is sufficient.
If you set this variable, do not also set `tags-file-name'.
-Use the `etags' program to make a tags table file.")
+Use the `etags' program to make a tags table file."
+ :group 'etags
+ :type '(repeat file))
;;;###autoload
-(defvar tags-add-tables 'ask-user
+(defcustom tags-add-tables 'ask-user
"*Control whether to add a new tags table to the current list.
t means do; nil means don't (always start a new list).
Any other value means ask the user whether to add a new tags table
-to the current list (as opposed to starting a new list).")
+to the current list (as opposed to starting a new list)."
+ :group 'etags
+ :type '(choice (const :tag "Do" t)
+ (const :tag "Don't" nil)
+ (other :tag "Ask" ask-user)))
+
+(defcustom tags-revert-without-query nil
+ "*Non-nil means reread a TAGS table without querying, if it has changed."
+ :group 'etags
+ :type 'boolean)
(defvar tags-table-computed-list nil
"List of tags tables to search, computed from `tags-table-list'.
Each element is a list of strings which are file names.")
;;;###autoload
-(defvar find-tag-hook nil
+(defcustom find-tag-hook nil
"*Hook to be run by \\[find-tag] after finding a tag. See `run-hooks'.
The value in the buffer in which \\[find-tag] is done is used,
-not the value in the buffer \\[find-tag] goes to.")
+not the value in the buffer \\[find-tag] goes to."
+ :group 'etags
+ :type 'hook)
;;;###autoload
-(defvar find-tag-default-function nil
+(defcustom find-tag-default-function nil
"*A function of no arguments used by \\[find-tag] to pick a default tag.
If nil, and the symbol that is the value of `major-mode'
has a `find-tag-default-function' property (see `put'), that is used.
-Otherwise, `find-tag-default' is used.")
+Otherwise, `find-tag-default' is used."
+ :group 'etags
+ :type 'function)
+
+(defcustom find-tag-marker-ring-length 16
+ "*Length of marker rings `find-tag-marker-ring' and `tags-location-ring'."
+ :group 'etags
+ :type 'integer
+ :version "20.3")
+
+(defvar find-tag-marker-ring (make-ring find-tag-marker-ring-length)
+ "Ring of markers which are locations from which \\[find-tag] was invoked.")
(defvar default-tags-table-function nil
"If non-nil, a function to choose a default tags file for a buffer.
This function receives no arguments and should return the default
tags table file to use for the current buffer.")
-(defvar tags-location-stack nil
- "List of markers which are locations visited by \\[find-tag].
+(defvar tags-location-ring (make-ring find-tag-marker-ring-length)
+ "Ring of markers which are locations visited by \\[find-tag].
Pop back to the last location with \\[negative-argument] \\[find-tag].")
\f
;; Tags table state.
;; These variables are local in tags table buffers.
-(defvar tag-lines-already-matched nil
- "List of positions of beginnings of lines within the tags table
-that are already matched.")
-
(defvar tags-table-files nil
"List of file names covered by current tags table.
nil means it has not yet been computed; use `tags-table-files' to do so.")
(defvar tags-table-format-hooks '(etags-recognize-tags-table
recognize-empty-tags-table)
- "List of functions to be called in a tags table buffer to identify
-the type of tags table. The functions are called in order, with no arguments,
+ "List of functions to be called in a tags table buffer to identify the type of tags table.
+The functions are called in order, with no arguments,
until one returns non-nil. The function should make buffer-local bindings
of the format-parsing tags function variables if successful.")
(defvar tags-included-tables-function nil
"Function to do the work of `tags-included-tables' (which see).")
(defvar verify-tags-table-function nil
- "Function to return t iff the current buffer contains a valid
-\(already initialized\) tags file.")
+ "Function to return t iff current buffer contains valid tags file.")
\f
;; Initialize the tags table in the current buffer.
;; Returns non-nil iff it is a valid tags table. On
;; non-nil return, the tags table state variable are
;; made buffer-local and initialized to nil.
(defun initialize-new-tags-table ()
- (set (make-local-variable 'tag-lines-already-matched) nil)
(set (make-local-variable 'tags-table-files) nil)
(set (make-local-variable 'tags-completion-table) nil)
(set (make-local-variable 'tags-included-tables) nil)
+ (setq find-tag-marker-ring (make-ring find-tag-marker-ring-length))
+ (setq tags-location-ring (make-ring find-tag-marker-ring-length))
;; Value is t if we have found a valid tags table buffer.
(let ((hooks tags-table-format-hooks))
(while (and hooks
(set-buffer (get-file-buffer file))
(setq win (or verify-tags-table-function (initialize-new-tags-table)))
(if (or (verify-visited-file-modtime (current-buffer))
- (not (yes-or-no-p
- (format "Tags file %s has changed, read new contents? "
- file))))
- (and win (funcall verify-tags-table-function))
+ ;; Decide whether to revert the file.
+ ;; revert-without-query can say to revert
+ ;; or the user can say to revert.
+ (not (or (let ((tail revert-without-query)
+ (found nil))
+ (while tail
+ (if (string-match (car tail) buffer-file-name)
+ (setq found t))
+ (setq tail (cdr tail)))
+ found)
+ tags-revert-without-query
+ (yes-or-no-p
+ (format "Tags file %s has changed, read new contents? "
+ file)))))
+ (and verify-tags-table-function
+ (funcall verify-tags-table-function))
(revert-buffer t t)
(initialize-new-tags-table)))
(and (file-exists-p file)
(cond ((eq cont 'same)
;; Use the ambient value of tags-file-name.
(or tags-file-name
- (error (substitute-command-keys
- (concat "No tags table in use! "
- "Use \\[visit-tags-table] to select one.")))))
+ (error "%s"
+ (substitute-command-keys
+ (concat "No tags table in use; "
+ "use \\[visit-tags-table] to select one")))))
((eq t cont)
;; Find the next table.
(error "File %s is not a valid tags table" local-tags-file-name)))))
(defun tags-reset-tags-tables ()
- "Reset tags state to cancel effect of any previous \\[visit-tags-table]
-or \\[find-tag]."
+ "Reset tags state to cancel effect of any previous \\[visit-tags-table] or \\[find-tag]."
(interactive)
(setq tags-file-name nil
- tags-location-stack nil
+ tags-location-ring (progn
+ (mapcar (lambda (m)
+ (set-marker m nil))
+ tags-location-ring)
+ (make-ring find-tag-marker-ring-length))
+ find-tag-marker-ring (progn
+ (mapcar (lambda (m)
+ (set-marker m nil))
+ find-tag-marker-ring)
+ (make-ring find-tag-marker-ring-length))
tags-table-list nil
tags-table-computed-list nil
tags-table-computed-list-for nil
(spec (completing-read (if default
(format "%s(default %s) " string default)
string)
- 'tags-complete-tag)))
+ 'tags-complete-tag
+ nil nil nil nil default)))
(if (equal spec "")
(or default (error "There is no default tag"))
spec)))
If third arg REGEXP-P is non-nil, treat TAGNAME as a regexp.
+A marker representing the point when this command is onvoked is pushed
+onto a ring and may be popped back to with \\[pop-tag-mark].
+Contrast this with the ring of marks gone to by the command.
+
See documentation of variable `tags-file-name'."
(interactive (find-tag-interactive "Find tag: "))
(let ((local-find-tag-hook find-tag-hook))
(if (eq '- next-p)
;; Pop back to a previous location.
- (if (null tags-location-stack)
+ (if (ring-empty-p tags-location-ring)
(error "No previous tag locations")
- (let ((marker (car tags-location-stack)))
- ;; Pop the stack.
- (setq tags-location-stack (cdr tags-location-stack))
+ (let ((marker (ring-remove tags-location-ring 0)))
(prog1
;; Move to the saved location.
- (set-buffer (marker-buffer marker))
+ (set-buffer (or (marker-buffer marker)
+ (error "The marked buffer has been deleted")))
(goto-char (marker-position marker))
;; Kill that marker so it doesn't slow down editing.
(set-marker marker nil nil)
;; Run the user's hook. Do we really want to do this for pop?
(run-hooks 'local-find-tag-hook))))
+ ;; Record whence we came.
+ (ring-insert find-tag-marker-ring (point-marker))
(if next-p
;; Find the same table we last used.
(visit-tags-table-buffer 'same)
(not next-p)))
(set-marker marker (point))
(run-hooks 'local-find-tag-hook)
- (setq tags-location-stack
- (cons marker tags-location-stack))
+ (ring-insert tags-location-ring marker)
(current-buffer))))))
;;;###autoload
is the atom `-' (interactively, with prefix arg that is a negative number
or just \\[negative-argument]), pop back to the previous tag gone to.
+If third arg REGEXP-P is non-nil, treat TAGNAME as a regexp.
+
+A marker representing the point when this command is onvoked is pushed
+onto a ring and may be popped back to with \\[pop-tag-mark].
+Contrast this with the ring of marks gone to by the command.
+
See documentation of variable `tags-file-name'."
(interactive (find-tag-interactive "Find tag: "))
(switch-to-buffer (find-tag-noselect tagname next-p regexp-p)))
is negative (interactively, with prefix arg that is a negative number or
just \\[negative-argument]), pop back to the previous tag gone to.
+If third arg REGEXP-P is non-nil, treat TAGNAME as a regexp.
+
+A marker representing the point when this command is onvoked is pushed
+onto a ring and may be popped back to with \\[pop-tag-mark].
+Contrast this with the ring of marks gone to by the command.
+
See documentation of variable `tags-file-name'."
(interactive (find-tag-interactive "Find tag other window: "))
is negative (interactively, with prefix arg that is a negative number or
just \\[negative-argument]), pop back to the previous tag gone to.
+If third arg REGEXP-P is non-nil, treat TAGNAME as a regexp.
+
+A marker representing the point when this command is onvoked is pushed
+onto a ring and may be popped back to with \\[pop-tag-mark].
+Contrast this with the ring of marks gone to by the command.
+
See documentation of variable `tags-file-name'."
(interactive (find-tag-interactive "Find tag other frame: "))
(let ((pop-up-frames t))
If third arg OTHER-WINDOW is non-nil, select the buffer in another window.
+A marker representing the point when this command is onvoked is pushed
+onto a ring and may be popped back to with \\[pop-tag-mark].
+Contrast this with the ring of marks gone to by the command.
+
See documentation of variable `tags-file-name'."
(interactive (find-tag-interactive "Find tag regexp: " t))
;; We go through find-tag-other-window to do all the display hair there.
(funcall (if other-window 'find-tag-other-window 'find-tag)
regexp next-p t))
;;;###autoload (define-key esc-map [?\C-.] 'find-tag-regexp)
+
+;;;###autoload (define-key esc-map "*" 'pop-tag-mark)
+
+;;;###autoload
+(defun pop-tag-mark ()
+ "Pop back to where \\[find-tag] was last invoked.
+
+This is distinct from invoking \\[find-tag] with a negative argument
+since that pops a stack of markers at which tags were found, not from
+where they were found."
+ (interactive)
+ (if (ring-empty-p find-tag-marker-ring)
+ (error "No previous locations for find-tag invocation"))
+ (let ((marker (ring-remove find-tag-marker-ring 0)))
+ (switch-to-buffer (or (marker-buffer marker)
+ (error "The marked buffer has been deleted")))
+ (goto-char (marker-position marker))
+ (set-marker marker nil nil)))
\f
;; Internal tag finding function.
;; specified source file and return. Qualified matches are remembered to
;; avoid repetition. State is saved so that the loop can be continued.
+(defvar tag-lines-already-matched nil) ;matches remembered here between calls
+
(defun find-tag-in-order (pattern
search-forward-func
order
tag-info ;where to find the tag in FILE
(first-table t)
(tag-order order)
+ (match-marker (make-marker))
goto-func
)
(save-excursion
- (or first-search ;find-tag-noselect has already done it.
- (visit-tags-table-buffer 'same))
+
+ (if first-search
+ ;; This is the start of a search for a fresh tag.
+ ;; Clear the list of tags matched by the previous search.
+ ;; find-tag-noselect has already put us in the first tags table
+ ;; buffer before we got called.
+ (setq tag-lines-already-matched nil)
+ ;; Continuing to search for the tag specified last time.
+ ;; tag-lines-already-matched lists locations matched in previous
+ ;; calls so we don't visit the same tag twice if it matches twice
+ ;; during two passes with different qualification predicates.
+ ;; Switch to the current tags table buffer.
+ (visit-tags-table-buffer 'same))
;; Get a qualified match.
(catch 'qualified-match-found
(while (or first-table
(visit-tags-table-buffer t))
- (if first-search
- (setq tag-lines-already-matched nil))
-
(and first-search first-table
;; Start at beginning of tags file.
(goto-char (point-min)))
;; Naive match found. Qualify the match.
(and (funcall (car order) pattern)
;; Make sure it is not a previous qualified match.
- ;; Use of `memq' depends on numbers being eq.
- (not (memq (save-excursion (beginning-of-line) (point))
- tag-lines-already-matched))
+ (not (member (set-marker match-marker (save-excursion
+ (beginning-of-line)
+ (point)))
+ tag-lines-already-matched))
(throw 'qualified-match-found nil))
(if next-line-after-failure-p
(forward-line 1)))
(goto-char (point-min)))
(setq order tag-order))
;; We throw out on match, so only get here if there were no matches.
+ ;; Clear out the markers we use to avoid duplicate matches so they
+ ;; don't slow down editting and are immediately available for GC.
+ (while tag-lines-already-matched
+ (set-marker (car tag-lines-already-matched) nil nil)
+ (setq tag-lines-already-matched (cdr tag-lines-already-matched)))
+ (set-marker match-marker nil nil)
(error "No %stags %s %s" (if first-search "" "more ")
matching pattern))
;; Found a tag; extract location info.
(beginning-of-line)
- (setq tag-lines-already-matched (cons (point)
+ (setq tag-lines-already-matched (cons match-marker
tag-lines-already-matched))
;; Expand the filename, using the tags table buffer's default-directory.
(setq file (expand-file-name (file-of-tag))
(defun etags-file-of-tag ()
(save-excursion
- (if (looking-at "./")
- (re-search-forward "\\([^\n]+\\),[0-9]*\n")
- (re-search-backward "\f\n\\([^\n]+\\),[0-9]*\n"))
- (buffer-substring (match-beginning 1) (match-end 1))))
+ (re-search-backward "\f\n\\([^\n]+\\),[0-9]*\n")
+ (expand-file-name (buffer-substring (match-beginning 1) (match-end 1))
+ (file-truename default-directory))))
(defun etags-tags-completion-table ()
;; a search window which expands until it hits the start of file.
(defun etags-goto-tag-location (tag-info)
(let ((startpos (cdr (cdr tag-info)))
+ (line (car (cdr tag-info)))
offset found pat)
(if (eq (car tag-info) t)
;; Direct file tag.
(cond (line (goto-line line))
- (position (goto-char position))
+ (startpos (goto-char startpos))
(t (error "etags.el BUG: bogus direct file tag")))
;; This constant is 1/2 the initial search window.
;; There is no sense in making it too small,
(if startpos (setq startpos (1+ startpos)))
;; If no char pos was given, try the given line number.
(or startpos
- (if (car (cdr tag-info))
- (setq startpos (progn (goto-line (car (cdr tag-info)))
+ (if line
+ (setq startpos (progn (goto-line line)
(point)))))
(or startpos
(setq startpos (point-min)))
(point)))))
(princ (if (looking-at "[^\n]+\001")
;; There is an explicit tag name; use that.
- (buffer-substring (point)
+ (buffer-substring (1+ (point)) ;skip \177
(progn (skip-chars-forward "^\001")
(point)))
tag)))
;; point should be just after a string that matches TAG.
(defun tag-word-match-p (tag)
(and (looking-at "\\b.*\177")
- (save-excursion (backward-char (1+ (length tag)))
+ (save-excursion (backward-char (length tag))
(looking-at "\\b"))))
(defun tag-exact-file-name-match-p (tag)
(and (looking-at ",")
- (save-excursion (backward-char (1+ (length tag)))
+ (save-excursion (backward-char (length tag))
(looking-at "\f\n"))))
;; t if point is in a tag line with a tag containing TAG as a substring.
(and novisit
(get-buffer " *next-file*")
(kill-buffer " *next-file*"))
- (error "All files processed."))
+ (error "All files processed"))
(let* ((next (car next-file-list))
(new (not (get-file-buffer next))))
;; Advance the list before trying to find the file.
"Form for `tags-loop-continue' to eval to change one file.")
(defvar tags-loop-scan
- '(error (substitute-command-keys
- "No \\[tags-search] or \\[tags-query-replace] in progress."))
+ '(error "%s"
+ (substitute-command-keys
+ "No \\[tags-search] or \\[tags-query-replace] in progress"))
"Form for `tags-loop-continue' to eval to scan one file.
If it returns non-nil, this file needs processing by evalling
\`tags-loop-operate'. Otherwise, move on to the next file.")
(defun select-tags-table-quit ()
"Kill the buffer and delete the selected window."
(interactive)
- (kill-buffer (current-buffer))
- (or (one-window-p)
- (delete-window)))
+ (quit-window t (selected-window)))
\f
+;;; Note, there is another definition of this function in bindings.el.
;;;###autoload
(defun complete-tag ()
"Perform tags completion on the text around point.
(interactive)
(or tags-table-list
tags-file-name
- (error (substitute-command-keys
- "No tags table loaded. Try \\[visit-tags-table].")))
+ (error "%s"
+ (substitute-command-keys
+ "No tags table loaded; try \\[visit-tags-table]")))
(let ((pattern (funcall (or find-tag-default-function
(get major-mode 'find-tag-default-function)
'find-tag-default)))
(display-completion-list
(all-completions pattern 'tags-complete-tag nil)))
(message "Making completion list...%s" "done")))))
-
-;;;###autoload (define-key esc-map "\t" 'complete-tag)
\f
(provide 'etags)