(magic-mode-alist): Use optimization for SGML mode too.

(set-auto-mode): Doc fix.  Remove unused variable `xml'.

diff --git a/lisp/files.el b/lisp/files.el
index a9a63019997ce9a28fbc17dd18a35871235c66cf..ad77688b6bcb43cef549a36b122cc62718edd248 100644 (file)
--- a/lisp/files.el
+++ b/lisp/files.el
@@ -1876,7 +1876,9 @@ with that interpreter in `interpreter-mode-alist'.")
                "[Hh][Tt][Mm][Ll]")) . html-mode)
     ;; These two must come after html, because they are more general:
     ("<\\?xml " . xml-mode)
-    ("\\s *<\\(?:!--\\(?:.\\|\n\\)*?-->\\s *<\\)*!DOCTYPE " . sgml-mode)
+    (,(let* ((incomment-re "\\(?:[^-]\\|-[^-]\\)")
+            (comment-re (concat "\\(?:!--" incomment-re "*-->\\s *<\\)")))
+       (concat "\\s *<" comment-re "*!DOCTYPE ")) . sgml-mode)
     ("%![^V]" . ps-mode)
     ("# xmcd " . conf-unix-mode))
   "Alist of buffer beginnings vs. corresponding major mode functions.
@@ -1888,9 +1890,8 @@ called, unless it is nil (to allow `auto-mode-alist' to override).")
 
 This checks for a -*- mode tag in the buffer's text, checks the
 interpreter that runs this file against `interpreter-mode-alist',
-compares the buffer beginning against `magic-mode-alist',
-or compares the filename against the entries in
-`auto-mode-alist'.
+compares the buffer beginning against `magic-mode-alist', or
+compares the filename against the entries in `auto-mode-alist'.
 
 It does not check for the `mode:' local variable in the
 Local Variables section of the file; for that, use `hack-local-variables'.
@@ -1901,13 +1902,11 @@ If `enable-local-variables' is nil, this function does not check for a
 If the optional argument KEEP-MODE-IF-SAME is non-nil, then we
 only set the major mode, if that would change it."
   ;; Look for -*-MODENAME-*- or -*- ... mode: MODENAME; ... -*-
-  (let (end done mode modes xml)
+  (let (end done mode modes)
     ;; Find a -*- mode tag
     (save-excursion
       (goto-char (point-min))
       (skip-chars-forward " \t\n")
-      ;; While we're at this point, check xml for later.
-      (setq xml (looking-at "<\\?xml \\|<!DOCTYPE"))
       (and enable-local-variables
           (setq end (set-auto-mode-1))
           (if (save-excursion (search-forward ":" end t))
@@ -1951,9 +1950,10 @@ only set the major mode, if that would change it."
            ;; same time.
            done (assoc (file-name-nondirectory mode)
                        interpreter-mode-alist))
+      ;; If we found an interpreter mode to use, invoke it now.
       (if done
          (set-auto-mode-0 (cdr done) keep-mode-if-same)))
-    ;; If we found an interpreter mode to use, invoke it now.
+    ;; If we didn't, match the buffer beginning against magic-mode-alist.
     (unless done
       (if (setq done (save-excursion
                       (goto-char (point-min))
@@ -1961,6 +1961,7 @@ only set the major mode, if that would change it."
                                      (lambda (re dummy)
                                        (looking-at re)))))
          (set-auto-mode-0 done keep-mode-if-same)
+       ;; Compare the filename against the entries in auto-mode-alist.
        (if buffer-file-name
            (let ((name buffer-file-name))
              ;; Remove backup-suffixes from file name.
@@ -1970,7 +1971,7 @@ only set the major mode, if that would change it."
                (let ((case-fold-search
                       (memq system-type '(vax-vms windows-nt cygwin))))
                  (if (and (setq mode (assoc-default name auto-mode-alist
-                                                'string-match))
+                                                    'string-match))
                           (consp mode)
                           (cadr mode))
                      (setq mode (car mode)
@@ -1979,7 +1980,6 @@ only set the major mode, if that would change it."
                (when mode
                  (set-auto-mode-0 mode keep-mode-if-same)))))))))
 
-
 ;; When `keep-mode-if-same' is set, we are working on behalf of
 ;; set-visited-file-name.  In that case, if the major mode specified is the
 ;; same one we already have, don't actually reset it.  We don't want to lose
@@ -1998,7 +1998,6 @@ same, do nothing and return nil."
     (funcall mode)
     mode))
 
-
 (defun set-auto-mode-1 ()
   "Find the -*- spec in the buffer.
 Call with point at the place to start searching from.