Changes for separate unspecified foreground and background colors

on character terminals:

* dispextern.h (FACE_TTY_DEFAULT_FG_COLOR)
(FACE_TTY_DEFAULT_BG_COLOR):  New macros.

* xfaces.c (Qunspecified_fg, Qunspecified_bg): New variables.
(syms_of_xfaces): Initialize and staticpro them.
(tty_defined_color): If the color name is unspecified-fg or
unspecified-bg, return FACE_TTY_DEFAULT_FG_COLOR and
FACE_TTY_DEFAULT_BG_COLOR, respectively, as the pixel value.
(tty_color_name): If the color pixel value is either
FACE_TTY_DEFAULT_FG_COLOR or FACE_TTY_DEFAULT_BG_COLOR, return
Qunspecified_fg or Qunspecified_bg, respectively.
(Finternal_set_lisp_face_attribute): Allow values Qunspecified_fg
and Qunspecified_bg for foreground and background colors.
(realize_default_face): If the foreground and background colors
are not specified, default to Qunspecified_fg and Qunspecified_bg.
(realize_tty_face): By default, set the face colors to
FACE_TTY_DEFAULT_FG_COLOR and FACE_TTY_DEFAULT_BG_COLOR.
[MSDOS]: Handle FACE_TTY_DEFAULT_FG_COLOR and
FACE_TTY_DEFAULT_BG_COLOR when face colors are not defined.
Reverse the colors if the default colors were reversed.

* dispnew.c (init_display): Initialize the frame pixels of the
initial frame to FACE_TTY_DEFAULT_FG_COLOR and
FACE_TTY_DEFAULT_BG_COLOR.

* term.c (turn_on_face): If the default fore- and background
colors are reversed, enter inverse video mode.  Don't send color
escape sequences for unspecified foreground and background colors.
(turn_off_face): Handle unspecified-fg and unspecified-bg colors.

* dosfns.c (unspecified_colors): New variable.
(msdos_stdcolor_idx): Handle unspecified-fg and unspecified-bg
color names, return FACE_TTY_DEFAULT_FG_COLOR and
FACE_TTY_DEFAULT_BG_COLOR, respectively.
(msdos_stdcolor_name): Handle FACE_TTY_DEFAULT_FG_COLOR and
FACE_TTY_DEFAULT_BG_COLOR, return Qunspecified_fg and
Qunspecified_bg, respectively.

* msdos.c (IT_set_face): Support FACE_TTY_DEFAULT_FG_COLOR and
FACE_TTY_DEFAULT_BG_COLOR as pixel values.

* faces.el (face-read-integer, read-face-attribute)
(color-defined-p, color-values): Allow color values unspecified-fg
and unspecified-bg, handle them as unspecified.

2 files changed, 19 insertions, 8 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 40e6d0ccb80..799ed3b55b9 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,9 @@
+1999-12-15  Eli Zaretskii  <eliz@is.elta.co.il>
+
+        * faces.el (face-read-integer, read-face-attribute)
+        (color-defined-p, color-values): Allow color values unspecified-fg
+        and unspecified-bg, handle them as unspecified.
+
 1999-12-15  Kenichi Handa  <handa@etl.go.jp>
 
         The following changes are for the new composition mechanism.  We
diff --git a/lisp/faces.el b/lisp/faces.el
index 80ed7fc12a7..f4e071222d3 100644
--- a/lisp/faces.el
+++ b/lisp/faces.el
@@ -827,12 +827,14 @@ value to return if no new value is entered.  NAME is a descriptive
 name of the attribute for prompting.  Value is the new attribute value."
   (let ((new-value
          (face-read-string face
-                           (if (eq default 'unspecified)
-                               'unspecified
+                           (if (memq
+                                default
+                                '(unspecified unspecified-fg unspecified-bg))
+                               default
                              (int-to-string default))
                            name
                            (list (cons "unspecified" 'unspecified)))))
-    (if (eq new-value 'unspecified)
+    (if (memq new-value '(unspecified unspecified-fg unspecified-bg))
         new-value
       (string-to-int new-value))))
 
@@ -862,7 +864,8 @@ of a global face.  Value is the new attribute value."
            ;; in tty-colors.el.
            (if (and (memq attribute '(:foreground :background))
                     (not (memq window-system '(x w32 mac)))
-                    (not (eq new-value 'unspecified)))
+                    (not (memq new-value
+                               '(unspecified unspecified-fg unspecified-bg))))
                (setq new-value (car (tty-color-desc new-value))))
            (unless (eq new-value 'unspecified)
              (setq new-value (cdr (assoc new-value valid)))))
@@ -1164,8 +1167,9 @@ If FRAME doesn't support colors, the value is nil."
 (defun color-defined-p (color &optional frame)
   "Return non-nil if color COLOR is supported on frame FRAME.
 If FRAME is omitted or nil, use the selected frame.
-If COLOR is the symbol `unspecified', the value is nil."
-  (if (eq color 'unspecified)
+If COLOR is one of the symbols `unspecified', `unspecified-fg', or
+`unspecified-bg', the value is nil."
+  (if (memq color '(unspecified unspecified-bg unspecified-fg))
       nil
     (if (memq (framep (or frame (selected-frame))) '(x w32))
         (xw-color-defined-p color frame)
@@ -1179,8 +1183,9 @@ These values appear to range from 0 to 65280 or 65535, depending
 on the system; white is \(65280 65280 65280\) or \(65535 65535 65535\).
 If FRAME is omitted or nil, use the selected frame.
 If FRAME cannot display COLOR, the value is nil.
-If COLOR is the symbol `unspecified', the value is nil."
-  (if (eq color 'unspecified)
+If COLOR is one of the symbols `unspecified', `unspecified-fg', or
+`unspecified-bg', the value is nil."
+  (if (memq color '(unspecified unspecified-fg unspecified-bg))
       nil
     (if (memq (framep (or frame (selected-frame))) '(x w32))
         (xw-color-values color frame)