X-Git-Url: https://code.delx.au/gnu-emacs/blobdiff_plain/51f32106f2de16e15de19e15ae714ff7f3e82b22..62b84d364597b0bd88864fc5e1ed689ef0b3e866:/lisp/dos-fns.el

diff --git a/lisp/dos-fns.el b/lisp/dos-fns.el
index 09267c28c1..c66cbc7933 100644
--- a/lisp/dos-fns.el
+++ b/lisp/dos-fns.el
@@ -1,6 +1,7 @@
-;;; dos-fns.el --- MS-Dos specific functions.
+;;; dos-fns.el --- MS-Dos specific functions
 
-;; Copyright (C) 1991, 1993, 1995, 1996 Free Software Foundation, Inc.
+;; Copyright (C) 1991, 1993, 1995, 1996, 2001, 2002, 2003, 2004,
+;;   2005, 2006, 2007 Free Software Foundation, Inc.
 
 ;; Maintainer: Morten Welinder <terra@diku.dk>
 ;; Keywords: internal
@@ -9,7 +10,7 @@
 
 ;; 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)
+;; the Free Software Foundation; either version 3, or (at your option)
 ;; any later version.
 
 ;; GNU Emacs is distributed in the hope that it will be useful,
@@ -19,8 +20,8 @@
 
 ;; 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.
+;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+;; Boston, MA 02110-1301, USA.
 
 ;;; Commentary:
 
@@ -31,9 +32,13 @@
 ;; This overrides a trivial definition in files.el.
 (defun convert-standard-filename (filename)
   "Convert a standard file's name to something suitable for the current OS.
-This function's standard definition is trivial; it just returns the argument.
-However, on some systems, the function is redefined
-with a definition that really does change some file names."
+This means to guarantee valid names and perhaps to canonicalize
+certain patterns.
+
+On Windows and DOS, replace invalid characters.  On DOS, make
+sure to obey the 8.3 limitations.  On Windows, turn Cygwin names
+into native names, and also turn slashes into backslashes if the
+shell requires it (see `w32-shell-dos-semantics')."
   (if (or (not (stringp filename))
 	  ;; This catches the case where FILENAME is "x:" or "x:/" or
 	  ;; "/", thus preventing infinite recursion.
@@ -42,7 +47,7 @@ with a definition that really does change some file names."
     (let ((flen (length filename)))
       ;; If FILENAME has a trailing slash, remove it and recurse.
       (if (memq (aref filename (1- flen)) '(?/ ?\\))
-	  (concat (convert-standard-filename 
+	  (concat (convert-standard-filename
 		   (substring filename 0 (1- flen)))
 		  "/")
 	(let* (;; ange-ftp gets in the way for names like "/foo:bar".
@@ -74,18 +79,25 @@ with a definition that really does change some file names."
 	    ;; Change a leading period to a leading underscore.
 	    (if (= (aref string 0) ?.)
 		(aset string 0 ?_))
+	    ;; If the name is longer than 8 chars, and doesn't have a
+	    ;; period, and we have a dash or underscore that isn't too
+	    ;; close to the beginning, change that to a period.  This
+	    ;; is so we could salvage more characters of the original
+	    ;; name by pushing them into the extension.
+	    (if (and (not (string-match "\\." string))
+		     (> (length string) 8)
+		     ;; We don't gain anything if we put the period closer
+		     ;; than 5 chars from the beginning (5 + 3 = 8).
+		     (setq i (string-match "[-_]" string 5)))
+		(aset string i ?\.))
 	    ;; Get rid of invalid characters.
 	    (while (setq i (string-match
 			    "[^-a-zA-Z0-9_.%~^$!#&{}@`'()\200-\376]"
 			    string))
 	      (aset string i ?_))
-	    ;; If we don't have a period,
-	    ;; and we have a dash or underscore that isn't the first char,
-	    ;; change that to a period.
-	    (if (and (not (string-match "\\." string))
-		     (setq i (string-match "[-_]" string 1)))
-		(aset string i ?\.))
 	    ;; If we don't have a period in the first 8 chars, insert one.
+	    ;; This enables to have 3 more characters from the original
+	    ;; name in the extension.
 	    (if (> (or (string-match "\\." string) (length string))
 		   8)
 		(setq string
@@ -98,13 +110,14 @@ with a definition that really does change some file names."
 	    (if (> (length string) (+ firstdot 4))
 		(setq string (substring string 0 (+ firstdot 4))))
 	    ;; Change all periods except the first one into underscores.
+	    ;; (DOS doesn't allow more than one period.)
 	    (while (string-match "\\." string (1+ firstdot))
 	      (setq i (string-match "\\." string (1+ firstdot)))
 	      (aset string i ?_))
-	    ;; If the last character of the original filename was `~',
-	    ;; make sure the munged name ends with it also.  This is so
-	    ;; a backup file retains its final `~'.
-	    (if (equal lastchar ?~)
+	    ;; If the last character of the original filename was `~' or `#',
+	    ;; make sure the munged name ends with it also.  This is so that
+	    ;; backup and auto-save files retain their telltale form.
+	    (if (memq lastchar '(?~ ?#))
 		(aset string (1- (length string)) lastchar))))
 	  (concat (if (and (stringp dir)
 			   (memq (aref dir dlen-m-1) '(?/ ?\\)))
@@ -244,4 +257,5 @@ that your video hardware might not support 50-line mode."
 
 (provide 'dos-fns)
 
-; dos-fns.el ends here
+;;; arch-tag: 00b03579-8ebb-4a02-8762-5c5a929774ad
+;;; dos-fns.el ends here