Added a comment explaining the various ways to save a game score on POSIX

systems.
(gamegrid-add-score-with-update-game-score): Use `cond' instead of `if'.
Provide for the case that FILE is an absolute filename.  Create the directory
"$HOME/.emacs.d/games", if necessary.

2 files changed, 61 insertions, 22 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 9c828d92dfa..ba620b86eb0 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,11 @@
+2003-04-29  Oliver Scholz  <epameinondas@gmx.de>
+
+        * play/gamegrid.el: Added a comment explaining the various ways to
+        save a game score on POSIX systems.
+        (gamegrid-add-score-with-update-game-score): Use `cond' instead of
+        `if'.  Provide for the case that FILE is an absolute filename.
+        Create the directory "$HOME/.emacs.d/games", if necessary.
+
 2003-04-29  John Paul Wallington  <jpw@gnu.org>
 
         * emacs-lisp/bytecomp.el (byte-compile-cl-warn): Use `string-match'.
diff --git a/lisp/play/gamegrid.el b/lisp/play/gamegrid.el
index 677b3e45268..540498d0971 100644
--- a/lisp/play/gamegrid.el
+++ b/lisp/play/gamegrid.el
@@ -450,6 +450,31 @@ FILE is created there."
     (t
      (gamegrid-add-score-with-update-game-score file score))))
 
+
+;; On POSIX systems there are four cases to distinguish:
+
+;;     1. FILE is an absolute filename.  Then it should be a file in
+;;        temporary file directory.  This is the way,
+;;        `gamegrid-add-score' was supposed to be used in the past and
+;;        is covered here for backward-compatibility.
+;;
+;;     2. The helper program "update-game-score" is setuid and the
+;;        file FILE does already exist in a system wide shared game
+;;        directory.  This should be the normal case on POSIX systems,
+;;        if the game was installed system wide.  Use
+;;        "update-game-score" to add the score to the file in the
+;;        shared game directory.
+;;
+;;     3. "update-game-score" is setuid, but the file FILE does *not*
+;;        exist in the system wide shared game directory.  Use
+;;        `gamegrid-add-score-insecure' to create--if necessary--and
+;;        update FILE.  This is for the case that a user has installed
+;;        a game on her own.
+;;
+;;     4. "update-game-score" is not setuid.  Use it to create/update
+;;        FILE in the user's home directory.  There is presumably no
+;;        shared game directory.
+
 (defun gamegrid-add-score-with-update-game-score (file score)
   (let* ((result nil) ;; What is this good for? -- os
          (have-shared-game-dir
@@ -457,28 +482,34 @@ FILE is created there."
                                (expand-file-name "update-game-score"
                                                  exec-directory))
                               #o4000)))))
-    (if (and have-shared-game-dir
-             (file-exists-p (expand-file-name file shared-game-score-directory)))
-        ;; Use the setuid update-gamescore program to update a
-        ;; system-wide score file.
-        (gamegrid-add-score-with-update-game-score-1
-         (expand-file-name file shared-game-score-directory) score)
-      ;; Else: Add the score to a score file in the user's home
-      ;; directory. If `have-shared-game-dir' is non-nil, the
-      ;; "update-gamescore" program is setuid, so don't use it.
-      (if have-shared-game-dir
-          (gamegrid-add-score-insecure file score
-                                       gamegrid-user-score-file-directory)
-        (let ((f (expand-file-name
-                  gamegrid-user-score-file-directory)))
-          (when (file-writable-p f)
-            (unless (eq (car-safe (file-attributes f))
-                        t)
-              (make-directory f))
-            (setq f (expand-file-name file f))
-            (unless (file-exists-p f)
-              (write-region "" nil f nil 'silent nil 'excl)))
-          (gamegrid-add-score-with-update-game-score-1 f score))))))
+    (cond ((file-name-absolute-p file)
+           (gamegrid-add-score-insecure file score))
+          ((and have-shared-game-dir
+                (file-exists-p (expand-file-name file shared-game-score-directory)))
+           ;; Use the setuid "update-game-score" program to update a
+           ;; system-wide score file.
+           (gamegrid-add-score-with-update-game-score-1
+            (expand-file-name file shared-game-score-directory) score))
+          ;; Else: Add the score to a score file in the user's home
+          ;; directory.
+          (have-shared-game-dir
+           ;; If `have-shared-game-dir' is non-nil, then
+           ;; "update-gamescore" program is setuid, so don't use it.
+           (unless (file-exists-p
+                    (directory-file-name gamegrid-user-score-file-directory))
+             (make-directory gamegrid-user-score-file-directory t))
+           (gamegrid-add-score-insecure file score
+                                        gamegrid-user-score-file-directory))
+          (t (let ((f (expand-file-name
+                       gamegrid-user-score-file-directory)))
+               (when (file-writable-p f)
+                 (unless (eq (car-safe (file-attributes f))
+                             t)
+                   (make-directory f))
+                 (setq f (expand-file-name file f))
+                 (unless (file-exists-p f)
+                   (write-region "" nil f nil 'silent nil 'excl)))
+               (gamegrid-add-score-with-update-game-score-1 f score))))))
 
 (defun gamegrid-add-score-with-update-game-score-1 (target score)
   (let ((default-directory "/")