(set-language-environment): On MS-DOS

terminals, install DOS-specific nonascii-translation-table if the
language info doesn't specify one.  Pass the default eol-type to
set-language-environment-coding-systems.
(set-default-coding-systems): Copy the eol-type property for the
new default values of {buffer-file,process}-coding-system from the
old defaults.
(set-language-environment-coding-systems): Accept an optional
argument EOL-TYPE, and set the eol-type property of the default
coding systems accordingly.
(set-terminal-coding-system): Enable menu item on MS-DOS terminals.
(set-keyboard-coding-system): Likewise.
(set-default-coding-systems): Don't set
default-terminal-coding-system on MS-DOS to anything but nil.
(prefer-coding-system): Describe in the doc string that
default-terminal-coding-system is not changed on MS-DOS.
(set-language-environment): For MS-DOS, set standard syntax table
and display table for all characters with code above 127.
(standard-display-european-internal): For MS-DOS, pass all
characters with code above 127 directly to the terminal, and don't
remap characters 160 and 146 in the unibyte case.

diff --git a/lisp/international/mule-cmds.el b/lisp/international/mule-cmds.el
index 8fc2a6d1160162b0bddd3d7a03a6af12975e6c9d..ee5241d495b151f1546cff4cc8ffc2678f8fdb1e 100644 (file)
--- a/lisp/international/mule-cmds.el
+++ b/lisp/international/mule-cmds.el
@@ -131,11 +131,11 @@
 (define-key setup-language-environment-map
   [Default] '("Default" . setup-specified-language-environment))
 
-;; These are meaningless when running under X.
+;; These are meaningless when running under X and W32.
 (put 'set-terminal-coding-system 'menu-enable
-     '(not window-system))
+     '(or (not window-system) (eq window-system 'pc)))
 (put 'set-keyboard-coding-system 'menu-enable
-     '(not window-system))
+     '(or (not window-system) (eq window-system 'pc)))
 ;; This is meaningless when the current buffer has no process.
 (put 'set-buffer-process-coding-system 'menu-enable
      '(get-buffer-process (current-buffer)))
@@ -212,13 +212,16 @@ This sets the following coding systems:
   o default coding system for subprocess I/O
 This also sets the following values:
   o default value used as file-name-coding-system for converting file names.
-  o default value for the command `set-terminal-coding-system'
-  o default value for the command `set-keyboard-coding-system'"
+  o default value for the command `set-terminal-coding-system' (not on MSDOS)
+  o default value for the command `set-keyboard-coding-system'."
   (check-coding-system coding-system)
   (setq-default buffer-file-coding-system coding-system)
   (if default-enable-multibyte-characters
       (setq default-file-name-coding-system coding-system))
-  (setq default-terminal-coding-system coding-system)
+  ;; If coding-system is nil, honor that on MS-DOS as well, so
+  ;; that they could reset the terminal coding system.
+  (unless (and (eq window-system 'pc) coding-system)
+    (setq default-terminal-coding-system coding-system))
   (setq default-keyboard-coding-system coding-system)
   (setq default-process-coding-system (cons coding-system coding-system)))
 
@@ -232,8 +235,13 @@ This also sets the following coding systems:
   o default coding system for subprocess I/O
 This also sets the following values:
   o default value used as file-name-coding-system for converting file names.
-  o default value for the command `set-terminal-coding-system'
-  o default value for the command `set-keyboard-coding-system'"
+  o default value for the command `set-terminal-coding-system' (not on MSDOS)
+  o default value for the command `set-keyboard-coding-system'
+
+This command does not change the default value of terminal coding system
+for MS-DOS terminal, because DOS terminals only support a single coding
+system, and Emacs automatically sets the default to that coding system at
+startup."
   (interactive "zPrefer coding system: ")
   (if (not (and coding-system (coding-system-p coding-system)))
       (error "Invalid coding system `%s'" coding-system))
@@ -528,7 +536,7 @@ it asks the user to select a proper coding system."
                 (point-min) (point-max) coding)
       coding)))
 \f
-;;; Language support staffs.
+;;; Language support stuff.
 
 (defvar language-info-alist nil
   "Alist of language environment definitions.
@@ -1162,10 +1170,12 @@ specifies the character set for the major languages of Western Europe."
                                     'exit-function)))
        (run-hooks 'exit-language-environment-hook)
        (if (fboundp func) (funcall func))))
-  (reset-language-environment)
+  (let ((default-eol-type (coding-system-eol-type
+                          default-buffer-file-coding-system)))
+    (reset-language-environment)
 
-  (setq current-language-environment language-name)
-  (set-language-environment-coding-systems language-name)
+    (setq current-language-environment language-name)
+    (set-language-environment-coding-systems language-name default-eol-type))
   (let ((input-method (get-language-info language-name 'input-method)))
     (when input-method
       (setq default-input-method input-method)
@@ -1174,10 +1184,20 @@ specifies the character set for the major languages of Western Europe."
                (cons input-method
                      (delete input-method input-method-history))))))
   (let ((nonascii (get-language-info language-name 'nonascii-translation)))
-    (if (char-table-p nonascii)
-       (setq nonascii-translation-table nonascii)      
-      (if (charsetp nonascii)
-         (setq nonascii-insert-offset (- (make-char nonascii) 128)))))
+    (cond
+     ((char-table-p nonascii)
+      (setq nonascii-translation-table nonascii))
+     ((eq window-system 'pc)
+      ;; DOS terminals' default is to use a special non-ASCII translation
+      ;; table as appropriate for the installed codepage.
+      (setq
+       nonascii-translation-table (symbol-value
+                                  (intern
+                                   (concat "cp"
+                                           dos-codepage
+                                           "-nonascii-translation-table")))))
+     ((charsetp nonascii)
+      (setq nonascii-insert-offset (- (make-char nonascii) 128)))))
 
   (setq charset-origin-alist
        (get-language-info language-name 'charset-origin-alist))
@@ -1192,7 +1212,7 @@ specifies the character set for the major languages of Western Europe."
        ;; No information for syntax and case.  Reset to the defaults.
        (let ((syntax-table (standard-syntax-table))
              (case-table (standard-case-table))
-             (ch 160))
+             (ch (if (eq window-system 'pc) 128 160)))
          (while (< ch 256)
            (modify-syntax-entry ch " " syntax-table)
            (aset case-table ch ch)
@@ -1209,12 +1229,11 @@ specifies the character set for the major languages of Western Europe."
     ;; Display table and coding system for terminal.
     (let ((coding (get-language-info language-name 'unibyte-display)))
       (if coding
-         (progn
-           (standard-display-european-internal)
-           (set-terminal-coding-system coding))
-       (standard-display-default 160 255)
-       (aset standard-display-table 146 nil)
-       (set-terminal-coding-system nil))))
+         (standard-display-european-internal)
+       (standard-display-default (if (eq window-system 'pc) 128 160) 255)
+       (aset standard-display-table 146 nil))
+      (or (eq window-system 'pc)
+         (set-terminal-coding-system coding))))
 
   (let ((required-features (get-language-info language-name 'features)))
     (while required-features
@@ -1228,22 +1247,34 @@ specifies the character set for the major languages of Western Europe."
 
 (defun standard-display-european-internal ()
   ;; Actually set up direct output of non-ASCII characters.
-  (standard-display-8bit 160 255)
-  ;; Make non-line-break space display as a plain space.
-  ;; Most X fonts do the wrong thing for code 160.
-  (aset standard-display-table 160 [32])
-  ;; Most Windows programs send out apostrophe's as \222.  Most X fonts
-  ;; don't contain a character at that position.  Map it to the ASCII
-  ;; apostrophe.
-  (aset standard-display-table 146 [39]))
-
-(defun set-language-environment-coding-systems (language-name)
-  "Do various coding system setups for language environment LANGUAGE-NAME."
+  (standard-display-8bit (if (eq window-system 'pc) 128 160) 255)
+  ;; Unibyte Emacs on MS-DOS wants to display all 8-bit characters with
+  ;; the native font, and codes 160 and 146 stand for something very
+  ;; different there.
+  (or (and (eq window-system 'pc) (not default-enable-multibyte-characters))
+      (progn
+       ;; Make non-line-break space display as a plain space.
+       ;; Most X fonts do the wrong thing for code 160.
+       (aset standard-display-table 160 [32])
+       ;; Most Windows programs send out apostrophe's as \222.  Most X fonts
+       ;; don't contain a character at that position.  Map it to the ASCII
+       ;; apostrophe.
+       (aset standard-display-table 146 [39]))))
+
+(defun set-language-environment-coding-systems (language-name
+                                               &optional eol-type)
+  "Do various coding system setups for language environment LANGUAGE-NAME.
+
+The optional arg EOL-TYPE specifies the eol-type of the default value
+of buffer-file-coding-system set by this function."
   (let* ((priority (get-language-info language-name 'coding-priority))
         (default-coding (car priority)))
     (if priority
        (let ((categories (mapcar 'coding-system-category priority)))
-         (set-default-coding-systems default-coding)
+         (set-default-coding-systems
+          (if (memq eol-type '(0 1 2 unix dos mac))
+              (coding-system-change-eol-conversion default-coding eol-type)
+            default-coding))
          (setq default-sendmail-coding-system default-coding)
          (set-coding-priority categories)
          (while priority