patch 8.0.1783: cannot use 256 colors in a MS-Windows console

Problem:    Cannot use 256 colors in a MS-Windows console.
Solution:   Add 256 color support. (Nobuhiro Takasaki, closes vim#2821)

src/misc1.c

@@ -3723,7 +3723,7 @@ vim_beep(
 		    /* No restore color information, refresh the screen. */
 		    if (has_vtp_working() != 0
 # ifdef FEAT_TERMGUICOLORS
-			    && p_tgc
+			    && (p_tgc || (!p_tgc && t_colors >= 256))
 # endif
 			)
 		    {

src/option.c

@@ -6082,6 +6082,9 @@ did_set_string_option(
     int		redraw_gui_only = FALSE;
 #endif
     int		ft_changed = FALSE;
+#if defined(FEAT_VTP) && defined(FEAT_TERMGUICOLORS)
+    int		did_swaptcap = FALSE;
+#endif
 
     /* Get the global option to compare with, otherwise we would have to check
      * two values for all local options. */
@@ -6821,6 +6824,13 @@ did_set_string_option(
 			vim_free(T_CCO);
 		    T_CCO = empty_option;
 		}
+#if defined(FEAT_VTP) && defined(FEAT_TERMGUICOLORS)
+		if (is_term_win32())
+		{
+		    swap_tcap();
+		    did_swaptcap = TRUE;
+		}
+#endif
 		/* We now have a different color setup, initialize it again. */
 		init_highlight(TRUE, FALSE);
 	    }
@@ -7674,6 +7684,16 @@ did_set_string_option(
 #endif
 	check_redraw(options[opt_idx].flags);
 
+#if defined(FEAT_VTP) && defined(FEAT_TERMGUICOLORS)
+    if (did_swaptcap)
+    {
+	if (t_colors < 256)
+	    p_tgc = 0;
+	set_termname((char_u *)"win32");
+	init_highlight(TRUE, FALSE);
+    }
+#endif
+
     return errmsg;
 }
 
@@ -8716,7 +8736,8 @@ set_bool_option(
 	    p_tgc = 0;
 	    return (char_u*)N_("E954: 24-bit colors are not supported on this environment");
 	}
-	swap_tcap();
+	if (is_term_win32())
+	    swap_tcap();
 # endif
 # ifdef FEAT_GUI
 	if (!gui.in_use && !gui.starting)
@@ -8725,7 +8746,7 @@ set_bool_option(
 # ifdef FEAT_VTP
 	control_console_color_rgb();
 	/* reset t_Co */
-	if (STRCMP(T_NAME, "win32") == 0)
+	if (is_term_win32())
 	    set_termname(T_NAME);
 # endif
     }

src/os_win32.c

@@ -214,7 +214,7 @@ static guicolor_T save_console_bg_rgb;
 static guicolor_T save_console_fg_rgb;
 
 # ifdef FEAT_TERMGUICOLORS
-#  define USE_VTP		(vtp_working && p_tgc)
+#  define USE_VTP		(vtp_working && is_term_win32() && (p_tgc || (!p_tgc && t_colors >= 256)))
 # else
 #  define USE_VTP		0
 # endif
@@ -2630,7 +2630,6 @@ mch_init(void)
 
     /* set termcap codes to current text attributes */
     update_tcap(g_attrCurrent);
-    swap_tcap();
 
     GetConsoleCursorInfo(g_hConOut, &g_cci);
     GetConsoleMode(g_hConIn,  &g_cmodein);
@@ -5763,7 +5762,11 @@ clear_chars(
     if (!USE_VTP)
 	FillConsoleOutputAttribute(g_hConOut, g_attrCurrent, n, coord, &dwDummy);
     else
-	FillConsoleOutputAttribute(g_hConOut, 0, n, coord, &dwDummy);
+    {
+	set_console_color_rgb();
+	gotoxy(coord.X + 1, coord.Y + 1);
+	vtp_printf("\033[%dX", n);
+    }
 }
 
 
@@ -7653,6 +7656,16 @@ vtp_sgr_bulks(
     vtp_printf((char *)buf);
 }
 
+    static int
+ctermtoxterm(
+    int cterm)
+{
+    uint8_t r, g, b, idx;
+
+    cterm_color2rgb(cterm, &r, &g, &b, &idx);
+    return (((int)r << 16) | ((int)g << 8) | (int)b);
+}
+
     static void
 set_console_color_rgb(void)
 {
@@ -7661,6 +7674,8 @@ set_console_color_rgb(void)
     int id;
     guicolor_T fg = INVALCOLOR;
     guicolor_T bg = INVALCOLOR;
+    int ctermfg;
+    int ctermbg;
 
     if (!USE_VTP)
 	return;
@@ -7669,9 +7684,19 @@ set_console_color_rgb(void)
     if (id > 0)
 	syn_id2colors(id, &fg, &bg);
     if (fg == INVALCOLOR)
-	fg = 0xc0c0c0;	    /* white text */
+    {
+	ctermfg = -1;
+	if (id > 0)
+	    syn_id2cterm_bg(id, &ctermfg, &ctermbg);
+	fg = ctermfg != -1 ? ctermtoxterm(ctermfg) : 0xc0c0c0; /* white */
+    }
     if (bg == INVALCOLOR)
-	bg = 0x000000;	    /* black background */
+    {
+	ctermbg = -1;
+	if (id > 0)
+	    syn_id2cterm_bg(id, &ctermfg, &ctermbg);
+	bg = ctermbg != -1 ? ctermtoxterm(ctermbg) : 0x000000; /* black */
+    }
     fg = (GetRValue(fg) << 16) | (GetGValue(fg) << 8) | GetBValue(fg);
     bg = (GetRValue(bg) << 16) | (GetGValue(bg) << 8) | GetBValue(bg);
 
@@ -7730,4 +7755,10 @@ use_vtp(void)
     return USE_VTP;
 }
 
+    int
+is_term_win32(void)
+{
+    return T_NAME != NULL && STRCMP(T_NAME, "win32") == 0;
+}
+
 #endif

src/proto/os_win32.pro

@@ -72,4 +72,5 @@ int mch_setenv(char *var, char *value, int x);
 void control_console_color_rgb(void);
 int has_vtp_working(void);
 int use_vtp(void);
+int is_term_win32(void);
 /* vim: set ft=c : */

src/proto/term.pro

@@ -76,4 +76,5 @@ void update_tcap(int attr);
 void swap_tcap(void);
 guicolor_T gui_get_color_cmn(char_u *name);
 guicolor_T gui_get_rgb_color_cmn(int r, int g, int b);
+void cterm_color2rgb(int nr, uint8_t *r, uint8_t *g, uint8_t *b, uint8_t *ansi_idx);
 /* vim: set ft=c : */