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.

1 files changed, 11 insertions, 3 deletions

diff --git a/src/term.c b/src/term.c
index 7900643dfdc..04f7a64866d 100644
--- a/src/term.c
+++ b/src/term.c
@@ -1959,7 +1959,9 @@ turn_on_face (f, face_id)
       && TN_magic_cookie_glitch_ul <= 0)
     OUTPUT1_IF (TS_enter_underline_mode);
 
-  if (face->tty_reverse_p)
+  if (face->tty_reverse_p
+      || face->foreground == FACE_TTY_DEFAULT_BG_COLOR
+      || face->background == FACE_TTY_DEFAULT_FG_COLOR)
     OUTPUT1_IF (TS_enter_reverse_mode);
 
   if (TN_max_colors > 0)
@@ -1967,6 +1969,8 @@ turn_on_face (f, face_id)
       char *p;
       
       if (face->foreground != FACE_TTY_DEFAULT_COLOR
+          && face->foreground != FACE_TTY_DEFAULT_FG_COLOR
+          && face->foreground != FACE_TTY_DEFAULT_BG_COLOR
           && TS_set_foreground)
         {
           p = tparam (TS_set_foreground, NULL, 0, (int) face->foreground);
@@ -1975,6 +1979,8 @@ turn_on_face (f, face_id)
         }
 
       if (face->background != FACE_TTY_DEFAULT_COLOR
+          && face->background != FACE_TTY_DEFAULT_BG_COLOR
+          && face->background != FACE_TTY_DEFAULT_FG_COLOR
           && TS_set_background)
         {
           p = tparam (TS_set_background, NULL, 0, (int) face->background);
@@ -2027,8 +2033,10 @@ turn_off_face (f, face_id)
 
   /* Switch back to default colors.  */
   if (TN_max_colors > 0
-      && (face->foreground != FACE_TTY_DEFAULT_COLOR
-          || face->background != FACE_TTY_DEFAULT_COLOR))
+      && ((face->foreground != FACE_TTY_DEFAULT_COLOR
+           && face->foreground != FACE_TTY_DEFAULT_FG_COLOR)
+          || (face->background != FACE_TTY_DEFAULT_COLOR
+              && face->background != FACE_TTY_DEFAULT_BG_COLOR)))
     OUTPUT1_IF (TS_orig_pair);
 }