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, 63 insertions, 19 deletions

diff --git a/src/xfaces.c b/src/xfaces.c
index 5fdb881bfc0..dd51df034ac 100644
--- a/src/xfaces.c
+++ b/src/xfaces.c
@@ -282,7 +282,7 @@ Lisp_Object Qsemi_condensed, Qsemi_expanded, Qexpanded, Qextra_expanded;
 Lisp_Object Qultra_expanded;
 Lisp_Object Qreleased_button, Qpressed_button;
 Lisp_Object QCstyle, QCcolor, QCline_width;
-Lisp_Object Qunspecified;
+Lisp_Object Qunspecified, Qunspecified_fg, Qunspecified_bg;
 
 /* The symbol `x-charset-registry'.  This property of charsets defines
    the X registry and encoding that fonts should have that are used to
@@ -1108,6 +1108,14 @@ tty_defined_color (f, color_name, color_def, alloc)
            load color" messages in the *Messages* buffer.  */
         status = 1;
     }
+  if (color_idx == FACE_TTY_DEFAULT_COLOR && *color_name)
+    {
+      if (strcmp (color_name, "unspecified-fg") == 0)
+        color_idx = FACE_TTY_DEFAULT_FG_COLOR;
+      else if (strcmp (color_name, "unspecified-bg") == 0)
+        color_idx = FACE_TTY_DEFAULT_BG_COLOR;
+    }
+
   color_def->pixel = (unsigned long) color_idx;
   color_def->red = red;
   color_def->green = green;
@@ -1179,7 +1187,10 @@ tty_color_name (f, idx)
      by index using the default color mapping on a Windows console.  */
 #endif
 
-  return Qunspecified;
+  return
+    idx == FACE_TTY_DEFAULT_FG_COLOR ? Qunspecified_fg
+    : idx == FACE_TTY_DEFAULT_BG_COLOR ? Qunspecified_bg
+    : Qunspecified;
 }
 
 /* Return non-zero if COLOR_NAME is a shade of gray (or white or
@@ -3427,7 +3438,8 @@ frame.")
     }
   else if (EQ (attr, QCforeground))
     {
-      if (!UNSPECIFIEDP (value))
+      if (!UNSPECIFIEDP (value)
+          && !EQ (value, Qunspecified_fg) && !EQ (value, Qunspecified_bg))
         {
           /* Don't check for valid color names here because it depends
              on the frame (display) whether the color will be valid
@@ -3441,7 +3453,8 @@ frame.")
     }
   else if (EQ (attr, QCbackground))
     {
-      if (!UNSPECIFIEDP (value))
+      if (!UNSPECIFIEDP (value)
+          && !EQ (value, Qunspecified_bg) && !EQ (value, Qunspecified_fg))
         {
           /* Don't check for valid color names here because it depends
              on the frame (display) whether the color will be valid
@@ -5686,7 +5699,9 @@ realize_default_face (f)
         LFACE_FOREGROUND (lface) = XCDR (color);
       else if (FRAME_X_P (f))
         return 0;
-      else if (!FRAME_TERMCAP_P (f) && !FRAME_MSDOS_P (f))
+      else if (FRAME_TERMCAP_P (f) || FRAME_MSDOS_P (f))
+        LFACE_FOREGROUND (lface) = Qunspecified_fg;
+      else
         abort ();
     }
   
@@ -5699,7 +5714,9 @@ realize_default_face (f)
         LFACE_BACKGROUND (lface) = XCDR (color);
       else if (FRAME_X_P (f))
         return 0;
-      else if (!FRAME_TERMCAP_P (f) && !FRAME_MSDOS_P (f))
+      else if (FRAME_TERMCAP_P (f) || FRAME_MSDOS_P (f))
+        LFACE_BACKGROUND (lface) = Qunspecified_bg;
+      else
         abort ();
     }
   
@@ -6072,7 +6089,8 @@ realize_tty_face (c, attrs, charset)
     face->tty_reverse_p = 1;
 
   /* Map color names to color indices.  */
-  face->foreground = face->background = FACE_TTY_DEFAULT_COLOR;
+  face->foreground = FACE_TTY_DEFAULT_FG_COLOR;
+  face->background = FACE_TTY_DEFAULT_BG_COLOR;
 
   color = attrs[LFACE_FOREGROUND_INDEX];
   if (STRINGP (color)
@@ -6084,7 +6102,7 @@ realize_tty_face (c, attrs, charset)
        (NAME INDEX R G B).  We need the INDEX part.  */
     face->foreground = XINT (XCAR (XCDR (color)));
 
-  if (face->foreground == FACE_TTY_DEFAULT_COLOR
+  if (face->foreground == FACE_TTY_DEFAULT_FG_COLOR
       && STRINGP (attrs[LFACE_FOREGROUND_INDEX]))
     {
       face->foreground = load_color (c->f, face,
@@ -6093,12 +6111,23 @@ realize_tty_face (c, attrs, charset)
 #ifdef MSDOS
       /* If the foreground of the default face is the default color,
          use the foreground color defined by the frame.  */
-      if (FRAME_MSDOS_P (c->f) && face->foreground == FACE_TTY_DEFAULT_COLOR)
+      if (FRAME_MSDOS_P (c->f))
         {
-          face->foreground = FRAME_FOREGROUND_PIXEL (f);
-          attrs[LFACE_FOREGROUND_INDEX] =
-            msdos_stdcolor_name (face->foreground);
-          face_colors_defaulted = 1;
+          if (face->foreground == FACE_TTY_DEFAULT_FG_COLOR
+              || face->foreground == FACE_TTY_DEFAULT_COLOR)
+            {
+              face->foreground = FRAME_FOREGROUND_PIXEL (f);
+              attrs[LFACE_FOREGROUND_INDEX] =
+                msdos_stdcolor_name (face->foreground);
+              face_colors_defaulted = 1;
+            }
+          else if (face->foreground == FACE_TTY_DEFAULT_BG_COLOR)
+            {
+              face->foreground = FRAME_BACKGROUND_PIXEL (f);
+              attrs[LFACE_FOREGROUND_INDEX] =
+                msdos_stdcolor_name (face->foreground);
+              face_colors_defaulted = 1;
+            }
         }
 #endif
     }
@@ -6113,7 +6142,7 @@ realize_tty_face (c, attrs, charset)
        (NAME INDEX R G B).  We need the INDEX part.  */
     face->background = XINT (XCAR (XCDR (color)));
 
-  if (face->background == FACE_TTY_DEFAULT_COLOR
+  if (face->background == FACE_TTY_DEFAULT_BG_COLOR
       && STRINGP (attrs[LFACE_BACKGROUND_INDEX]))
     {
       face->background = load_color (c->f, face,
@@ -6122,12 +6151,23 @@ realize_tty_face (c, attrs, charset)
 #ifdef MSDOS
       /* If the background of the default face is the default color,
          use the background color defined by the frame.  */
-      if (FRAME_MSDOS_P (c->f) && face->background == FACE_TTY_DEFAULT_COLOR)
+      if (FRAME_MSDOS_P (c->f))
         {
-          face->background = FRAME_BACKGROUND_PIXEL (f);
-          attrs[LFACE_BACKGROUND_INDEX] =
-            msdos_stdcolor_name (face->background);
-          face_colors_defaulted = 1;
+          if (face->background == FACE_TTY_DEFAULT_BG_COLOR
+              || face->background == FACE_TTY_DEFAULT_COLOR)
+            {
+              face->background = FRAME_BACKGROUND_PIXEL (f);
+              attrs[LFACE_BACKGROUND_INDEX] =
+                msdos_stdcolor_name (face->background);
+              face_colors_defaulted = 1;
+            }
+          else if (face->background == FACE_TTY_DEFAULT_FG_COLOR)
+            {
+              face->background = FRAME_FOREGROUND_PIXEL (f);
+              attrs[LFACE_BACKGROUND_INDEX] =
+                msdos_stdcolor_name (face->background);
+              face_colors_defaulted = 1;
+            }
         }
 #endif
     }
@@ -6611,6 +6651,10 @@ syms_of_xfaces ()
   staticpro (&Qforeground_color);
   Qunspecified = intern ("unspecified");
   staticpro (&Qunspecified);
+  Qunspecified_fg = intern ("unspecified-fg");
+  staticpro (&Qunspecified_fg);
+  Qunspecified_bg = intern ("unspecified-bg");
+  staticpro (&Qunspecified_bg);
 
   Qx_charset_registry = intern ("x-charset-registry");
   staticpro (&Qx_charset_registry);