(U-000200B5): Use `->denotational'; use
[chise/xemacs-chise.git.1] / lisp / find-paths.el
1 ;;; find-paths.el --- setup various XEmacs paths
2
3 ;; Copyright (C) 1985-1986, 1990, 1992-1997 Free Software Foundation, Inc.
4 ;; Copyright (c) 1993, 1994 Sun Microsystems, Inc.
5 ;; Copyright (C) 1995 Board of Trustees, University of Illinois
6
7 ;; Author: Mike Sperber <sperber@informatik.uni-tuebingen.de>
8 ;; Maintainer: XEmacs Development Team
9 ;; Keywords: internal, dumped
10
11 ;; This file is part of XEmacs.
12
13 ;; XEmacs is free software; you can redistribute it and/or modify it
14 ;; under the terms of the GNU General Public License as published by
15 ;; the Free Software Foundation; either version 2, or (at your option)
16 ;; any later version.
17
18 ;; XEmacs is distributed in the hope that it will be useful, but
19 ;; WITHOUT ANY WARRANTY; without even the implied warranty of
20 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
21 ;; General Public License for more details.
22
23 ;; You should have received a copy of the GNU General Public License
24 ;; along with XEmacs; see the file COPYING.  If not, write to the 
25 ;; Free Software Foundation, 59 Temple Place - Suite 330,
26 ;; Boston, MA 02111-1307, USA.
27
28 ;;; Synched up with: Not in FSF.
29
30 ;;; Commentary:
31
32 ;; This file is dumped with XEmacs.
33
34 ;; This file contains the library functionality to find paths into the
35 ;; XEmacs hierarchy.
36 \f
37 ;;; Code:
38
39 (defvar paths-version-control-filename-regexp
40   "^\\(RCS\\|CVS\\|SCCS\\)$"
41   "File bases associated with version control.")
42
43 (defvar paths-lisp-filename-regexp
44   "^\\(.*\\.elc?\\)$"
45   "File bases that contain Lisp file.")
46
47 (defvar paths-no-lisp-directory-regexp
48   (concat "\\(" paths-version-control-filename-regexp "\\)"
49           "\\|"
50           "\\(" paths-lisp-filename-regexp "\\)")
51   "File bases that may not be directories containing Lisp code.")
52
53 (defun paths-find-recursive-path (directories &optional max-depth exclude-regexp)
54   "Return a list of the directory hierarchy underneath DIRECTORIES.
55 The returned list is sorted by pre-order and lexicographically.
56 MAX-DEPTH limits the depth of the search to MAX-DEPTH level,
57 if it is a number.  If MAX-DEPTH is NIL, the search depth is unlimited.
58 EXCLUDE-REGEXP is a regexp that matches directory names to exclude
59 from the search."
60   (let ((path '()))
61     (while directories
62       (let ((directory (file-name-as-directory
63                         (expand-file-name
64                          (car directories)))))
65         (if (paths-file-readable-directory-p directory)
66             (let ((raw-entries
67                    (if (equal 0 max-depth)
68                        '()
69                      (directory-files directory nil "^[^.-]")))
70                   (reverse-dirs '()))
71               (while raw-entries
72                 (if (not (and exclude-regexp
73                               (string-match exclude-regexp (car raw-entries))))
74                     (setq reverse-dirs
75                           (cons (expand-file-name (car raw-entries) directory)
76                                 reverse-dirs)))
77                 (setq raw-entries (cdr raw-entries)))
78
79               (let ((sub-path
80                      (paths-find-recursive-path (reverse reverse-dirs)
81                                                 (if (numberp max-depth)
82                                                     (- max-depth 1)
83                                                   max-depth)
84                                                 exclude-regexp)))
85                 (setq path (nconc path
86                                   (list directory)
87                                   sub-path))))))
88       (setq directories (cdr directories)))
89     path))
90
91 (defun paths-file-readable-directory-p (filename)
92   "Check if filename is a readable directory."
93   (and (file-directory-p filename)
94        (file-readable-p filename)))
95
96 (defun paths-find-recursive-load-path (directories &optional max-depth)
97   "Construct a recursive load path underneath DIRECTORIES."
98   (paths-find-recursive-path directories
99                              max-depth paths-no-lisp-directory-regexp))
100
101 (defun paths-emacs-root-p (directory)
102   "Check if DIRECTORY is a plausible installation root for XEmacs."
103   (or
104    ;; installed
105    (paths-file-readable-directory-p (paths-construct-path (list directory
106                                                                 "lib"
107                                                                 emacs-program-name)))
108    ;; in-place or windows-nt
109    (and
110     (paths-file-readable-directory-p (paths-construct-path (list directory "lisp")))
111     (paths-file-readable-directory-p (paths-construct-path (list directory "etc"))))
112
113    ;; searching for a package directory on Windows
114    (and
115     (string-match "win32\\|cygwin" system-configuration)
116     (paths-file-readable-directory-p (paths-construct-path (list directory "xemacs-packages"))))))
117
118 (defun paths-root-in-place-p (root)
119   "Check if ROOT is an in-place installation root for XEmacs."
120   (paths-file-readable-directory-p (paths-construct-path (list root "lisp"))))
121
122 (defun paths-chase-symlink (file-name)
123   "Chase a symlink until the bitter end."
124       (let ((maybe-symlink (file-symlink-p file-name)))
125         (if maybe-symlink
126             (let* ((directory (file-name-directory file-name))
127                    (destination (expand-file-name maybe-symlink directory)))
128               (paths-chase-symlink destination))
129           file-name)))
130
131 (defun paths-find-invocation-roots (invocation-directory invocation-name)
132   "Find the list of run-time roots of XEmacs.
133 INVOCATION-DIRECTORY is a directory containing the XEmacs executable.
134 INVOCATION-NAME is the name of the executable itself."
135   (let* ((executable-file-name (paths-chase-symlink
136                                 (concat invocation-directory
137                                         invocation-name)))
138          (executable-directory (file-name-directory executable-file-name))
139          (maybe-root-1 (file-name-as-directory
140                         (paths-construct-path '("..") executable-directory)))
141          (maybe-root-2 (file-name-as-directory
142                         (paths-construct-path '(".." "..") executable-directory))))
143
144     (paths-filter #'paths-emacs-root-p
145                   (list maybe-root-1 maybe-root-2))))
146
147 (defun paths-construct-path (components &optional expand-directory)
148   "Convert list of path components COMPONENTS into a path.
149 If EXPAND-DIRECTORY is non-NIL, use it as a directory to feed
150 to EXPAND-FILE-NAME."
151   (let* ((reverse-components (reverse components))
152          (last-component (car reverse-components))
153          (first-components (reverse (cdr reverse-components)))
154          (path
155           (apply #'concat
156                  (append (mapcar #'file-name-as-directory first-components)
157                          (list last-component)))))
158     (if expand-directory
159         (expand-file-name path expand-directory)
160       path)))
161
162 (defun paths-construct-emacs-directory (root suffix base)
163   "Construct a directory name within the XEmacs hierarchy."
164   (file-name-as-directory
165    (expand-file-name
166     (concat
167      (file-name-as-directory root)
168      suffix
169      base))))
170
171 (defun paths-find-emacs-directory (roots suffix base
172                                    &optional envvar default keep-suffix
173                                              in-place-external)
174   "Find a directory in the XEmacs hierarchy.
175 ROOTS must be a list of installation roots.
176 SUFFIX is the subdirectory from there.
177 BASE is the base to look for.
178 ENVVAR is the name of the environment variable that might also
179 specify the directory.
180 DEFAULT is the preferred value.
181 If KEEP-SUFFIX is non-nil, the suffix must be respected in searching
182 the directory.
183 If IN-PLACE-EXTERNAL is non-nil, the directory might be found outside
184 an in-place root-hierarchy."
185   (let ((preferred-value (or (and envvar (getenv envvar))
186                              default)))
187     (if (and preferred-value
188              (paths-file-readable-directory-p preferred-value))
189         (file-name-as-directory preferred-value)
190       (catch 'gotcha
191         (while roots
192           (let ((root (car roots)))
193             ;; installed
194             (let ((path (paths-construct-emacs-directory root suffix base)))
195               (if (paths-file-readable-directory-p path)
196                   (throw 'gotcha path)))
197             ;; in-place
198             (if (null keep-suffix)
199                 (let ((path (paths-construct-emacs-directory root "" base)))
200                   (if (paths-file-readable-directory-p path)
201                       (throw 'gotcha path))))
202             (if (and in-place-external
203                      (paths-root-in-place-p root))
204                 (let ((path (paths-construct-emacs-directory
205                              (paths-construct-path '("..") root)
206                              "" base)))
207                   (if (paths-file-readable-directory-p path)
208                       (throw 'gotcha path)))))
209           (setq roots (cdr roots)))
210         nil))))
211
212 (defun paths-find-site-directory (roots base &optional envvar default in-place-external)
213   "Find a site-specific directory in the XEmacs hierarchy.
214 If IN-PLACE-EXTERNAL is non-nil, the directory might be found outside
215 an in-place root-hierarchy."
216   (paths-find-emacs-directory roots
217                               (file-name-as-directory
218                                (paths-construct-path (list
219                                                       "lib"
220                                                       emacs-program-name)))
221                               base
222                               envvar default
223                               nil
224                               in-place-external))
225
226 (defun paths-find-version-directory (roots base
227                                      &optional envvar default enforce-version)
228   "Find a version-specific directory in the XEmacs hierarchy.
229 If ENFORCE-VERSION is non-nil, the directory must contain the XEmacs version."
230   (paths-find-emacs-directory roots
231                               (file-name-as-directory
232                                (paths-construct-path
233                                 (list "lib"
234                                       (construct-emacs-version-name))))
235                               base
236                               envvar default
237                               enforce-version))
238
239 (defun paths-find-architecture-directory (roots base &optional envvar default)
240   "Find an architecture-specific directory in the XEmacs hierarchy."
241   (or
242    ;; from more to less specific
243    (paths-find-version-directory roots
244                                  (paths-construct-path
245                                   (list system-configuration base))
246                                  envvar default)
247    (paths-find-version-directory roots
248                                  base
249                                  envvar)
250    (paths-find-version-directory roots
251                                  system-configuration
252                                  envvar)))
253
254 (defun construct-emacs-version-name ()
255   "Construct the raw XEmacs version number."
256   (concat emacs-program-name "-" emacs-program-version))
257
258 (defun paths-directories-which-exist (directories)
259   "Return the directories among DIRECTORIES."
260   (let ((reverse-directories '()))
261     (while directories
262       (if (paths-file-readable-directory-p (car directories))
263           (setq reverse-directories
264                 (cons (car directories)
265                       reverse-directories)))
266       (setq directories (cdr directories)))
267     (reverse reverse-directories)))
268
269 (defun paths-uniq-append (list-1 list-2)
270   "Append LIST-1 and LIST-2, omitting duplicates."
271   (let ((reverse-survivors '()))
272     (while list-2
273       (if (null (member (car list-2) list-1))
274           (setq reverse-survivors (cons (car list-2) reverse-survivors)))
275       (setq list-2 (cdr list-2)))
276     (append list-1
277             (reverse reverse-survivors))))
278
279 (defun paths-filter (predicate list)
280   "Delete all matches of PREDICATE from LIST."
281   (let ((reverse-result '()))
282     (while list
283       (if (funcall predicate (car list))
284           (setq reverse-result (cons (car list) reverse-result)))
285       (setq list (cdr list)))
286     (nreverse reverse-result)))
287
288 (defun paths-decode-directory-path (string &optional drop-empties)
289   "Split STRING at path separators into a directory list.
290 Non-\"\" components are converted into directory form.
291 If DROP-EMPTIES is non-NIL, \"\" components are dropped from the output.
292 Otherwise, they are left alone."
293   (let* ((components (split-path string))
294          (directories
295           (mapcar #'(lambda (component)
296                       (if (string-equal "" component)
297                           component
298                         (file-name-as-directory component)))
299                   components)))
300     (if drop-empties
301         (paths-filter #'(lambda (component)
302                           (null (string-equal "" component)))
303                       directories)
304       directories)))
305
306 (defun paths-find-emacs-roots (invocation-directory
307                                invocation-name)
308   "Find all plausible installation roots for XEmacs."
309   (let* ((invocation-roots
310           (paths-find-invocation-roots invocation-directory invocation-name))
311          (potential-installation-roots
312           (paths-uniq-append
313            (and configure-exec-prefix-directory
314                 (list (file-name-as-directory
315                        configure-exec-prefix-directory)))
316            (and configure-prefix-directory
317                 (list (file-name-as-directory
318                        configure-prefix-directory)))))
319          (installation-roots
320           (paths-filter #'paths-emacs-root-p potential-installation-roots)))
321     (paths-uniq-append invocation-roots
322                        installation-roots)))
323
324 ;;; find-paths.el ends here