Add a cursor-colour option, from Alexis Hildebrandt in GitHub issue

2959.

input.c

@@ -137,10 +137,12 @@ static void	input_reset_cell(struct input_ctx *);
 static void	input_osc_4(struct input_ctx *, const char *);
 static void	input_osc_10(struct input_ctx *, const char *);
 static void	input_osc_11(struct input_ctx *, const char *);
+static void	input_osc_12(struct input_ctx *, const char *);
 static void	input_osc_52(struct input_ctx *, const char *);
 static void	input_osc_104(struct input_ctx *, const char *);
 static void	input_osc_110(struct input_ctx *, const char *);
 static void	input_osc_111(struct input_ctx *, const char *);
+static void	input_osc_112(struct input_ctx *, const char *);
 
 /* Transition entry/exit handlers. */
 static void	input_clear(struct input_ctx *);
@@ -2310,8 +2312,7 @@ input_exit_osc(struct input_ctx *ictx)
 		input_osc_11(ictx, p);
 		break;
 	case 12:
-		if (utf8_isvalid(p) && *p != '?') /* ? is colour request */
-			screen_set_cursor_colour(sctx->s, p);
+		input_osc_12(ictx, p);
 		break;
 	case 52:
 		input_osc_52(ictx, p);
@@ -2326,8 +2327,7 @@ input_exit_osc(struct input_ctx *ictx)
 		input_osc_111(ictx, p);
 		break;
 	case 112:
-		if (*p == '\0') /* no arguments allowed */
-			screen_set_cursor_colour(sctx->s, "");
+		input_osc_112(ictx, p);
 		break;
 	default:
 		log_debug("%s: unknown '%u'", __func__, option);
@@ -2489,7 +2489,9 @@ input_osc_colour_reply(struct input_ctx *ictx, u_int n, int c)
     u_char	 r, g, b;
     const char	*end;
 
-    if (c == 8 || (~c & COLOUR_FLAG_RGB))
+    if (c != -1)
+	    c = colour_force_rgb(c);
+    if (c == -1)
 	    return;
     colour_split_rgb(c, &r, &g, &b);
 
@@ -2564,7 +2566,7 @@ input_osc_10(struct input_ctx *ictx, const char *p)
 	}
 }
 
-/* Handle the OSC 110 sequence for resetting background colour. */
+/* Handle the OSC 110 sequence for resetting foreground colour. */
 static void
 input_osc_110(struct input_ctx *ictx, const char *p)
 {
@@ -2624,6 +2626,39 @@ input_osc_111(struct input_ctx *ictx, const char *p)
 	}
 }
 
+/* Handle the OSC 12 sequence for setting and querying cursor colour. */
+static void
+input_osc_12(struct input_ctx *ictx, const char *p)
+{
+	struct window_pane	*wp = ictx->wp;
+	int			 c;
+
+	if (strcmp(p, "?") == 0) {
+		if (wp != NULL) {
+			c = ictx->ctx.s->ccolour;
+			if (c == -1)
+				c = ictx->ctx.s->default_ccolour;
+			input_osc_colour_reply(ictx, 12, c);
+		}
+		return;
+	}
+
+	if ((c = input_osc_parse_colour(p)) == -1) {
+		log_debug("bad OSC 12: %s", p);
+		return;
+	}
+	screen_set_cursor_colour(ictx->ctx.s, c);
+}
+
+/* Handle the OSC 112 sequence for resetting cursor colour. */
+static void
+input_osc_112(struct input_ctx *ictx, const char *p)
+{
+	if (*p == '\0') /* no arguments allowed */
+		screen_set_cursor_colour(ictx->ctx.s, -1);
+}
+
+
 /* Handle the OSC 52 sequence for setting the clipboard. */
 static void
 input_osc_52(struct input_ctx *ictx, const char *p)

options-table.c

@@ -188,6 +188,7 @@ const struct options_name_map options_other_names[] = {
 	{ "display-panes-color", "display-panes-colour" },
 	{ "display-panes-active-color", "display-panes-active-colour" },
 	{ "clock-mode-color", "clock-mode-colour" },
+	{ "cursor-color", "cursor-colour" },
 	{ "pane-colors", "pane-colours" },
 	{ NULL, NULL }
 };
@@ -235,6 +236,13 @@ const struct options_table_entry options_table[] = {
 		  "If empty, no command is run."
 	},
 
+	{ .name = "cursor-colour",
+	  .type = OPTIONS_TABLE_COLOUR,
+	  .scope = OPTIONS_TABLE_WINDOW|OPTIONS_TABLE_PANE,
+	  .default_num = -1,
+	  .text = "Colour of the cursor."
+	},
+
 	{ .name = "default-terminal",
 	  .type = OPTIONS_TABLE_STRING,
 	  .scope = OPTIONS_TABLE_SERVER,

options.c

@@ -1106,15 +1106,22 @@ options_push_changes(const char *name)
 	struct session		*s;
 	struct window		*w;
 	struct window_pane	*wp;
+	int			 c;
 
 	if (strcmp(name, "automatic-rename") == 0) {
 		RB_FOREACH(w, windows, &windows) {
 			if (w->active == NULL)
 				continue;
-			if (options_get_number(w->options, "automatic-rename"))
+			if (options_get_number(w->options, name))
 				w->active->flags |= PANE_CHANGED;
 		}
 	}
+	if (strcmp(name, "cursor-colour") == 0) {
+		RB_FOREACH(wp, window_pane_tree, &all_window_panes) {
+			c = options_get_number(wp->options, name);
+			wp->screen->default_ccolour = c;
+		}
+	}
 	if (strcmp(name, "key-table") == 0) {
 		TAILQ_FOREACH(loop, &clients, entry)
 			server_client_set_key_table(loop, NULL);

screen.c

@@ -82,7 +82,8 @@ screen_init(struct screen *s, u_int sx, u_int sy, u_int hlimit)
 	s->path = NULL;
 
 	s->cstyle = SCREEN_CURSOR_DEFAULT;
-	s->ccolour = xstrdup("");
+	s->ccolour = -1;
+	s->default_ccolour = -1;
 	s->tabs = NULL;
 	s->sel = NULL;
 
@@ -126,7 +127,6 @@ screen_free(struct screen *s)
 	free(s->tabs);
 	free(s->path);
 	free(s->title);
-	free(s->ccolour);
 
 	if (s->write_list != NULL)
 		screen_write_free_list(s);
@@ -190,10 +190,9 @@ screen_set_cursor_style(struct screen *s, u_int style)
 
 /* Set screen cursor colour. */
 void
-screen_set_cursor_colour(struct screen *s, const char *colour)
+screen_set_cursor_colour(struct screen *s, int colour)
 {
-	free(s->ccolour);
-	s->ccolour = xstrdup(colour);
+	s->ccolour = colour;
 }
 
 /* Set screen title. */

tmux.1

@@ -4416,6 +4416,9 @@ The alternate screen feature preserves the contents of the window when an
 interactive application starts and restores it on exit, so that any output
 visible before the application starts reappears unchanged after it exits.
 .Pp
+.It Ic cursor-colour Ar colour
+Set the colour of the cursor.
+.Pp
 .It Ic pane-colours[] Ar colour
 The default colour palette.
 Each entry in the array defines the colour

tmux.h

@@ -779,7 +779,8 @@ struct screen {
 	u_int				 cy;	  /* cursor y */
 
 	enum screen_cursor_style	 cstyle;  /* cursor style */
-	char				*ccolour; /* cursor colour */
+	int				 ccolour; /* cursor colour */
+	int				 default_ccolour;
 
 	u_int				 rupper;  /* scroll region top */
 	u_int				 rlower;  /* scroll region bottom */
@@ -1276,7 +1277,7 @@ struct tty {
 	u_int		 cx;
 	u_int		 cy;
 	enum screen_cursor_style cstyle;
-	char		*ccolour;
+	int		 ccolour;
 
 	int		 oflag;
 	u_int		 oox;
@@ -2793,7 +2794,7 @@ void	 screen_reinit(struct screen *);
 void	 screen_free(struct screen *);
 void	 screen_reset_tabs(struct screen *);
 void	 screen_set_cursor_style(struct screen *, u_int);
-void	 screen_set_cursor_colour(struct screen *, const char *);
+void	 screen_set_cursor_colour(struct screen *, int);
 int	 screen_set_title(struct screen *, const char *);
 void	 screen_set_path(struct screen *, const char *);
 void	 screen_push_title(struct screen *);

tty.c

@@ -38,7 +38,7 @@ static int	tty_client_ready(struct client *);
 
 static void	tty_set_italics(struct tty *);
 static int	tty_try_colour(struct tty *, int, const char *);
-static void	tty_force_cursor_colour(struct tty *, const char *);
+static void	tty_force_cursor_colour(struct tty *, int);
 static void	tty_cursor_pane(struct tty *, const struct tty_ctx *, u_int,
 		    u_int);
 static void	tty_cursor_pane_unless_wrap(struct tty *,
@@ -105,7 +105,7 @@ tty_init(struct tty *tty, struct client *c)
 	tty->client = c;
 
 	tty->cstyle = SCREEN_CURSOR_DEFAULT;
-	tty->ccolour = xstrdup("");
+	tty->ccolour = -1;
 
 	if (tcgetattr(c->fd, &tty->tio) != 0)
 		return (-1);
@@ -341,8 +341,8 @@ tty_start_tty(struct tty *tty)
 	tty->flags |= TTY_STARTED;
 	tty_invalidate(tty);
 
-	if (*tty->ccolour != '\0')
-		tty_force_cursor_colour(tty, "");
+	if (tty->ccolour != -1)
+		tty_force_cursor_colour(tty, -1);
 
 	tty->mouse_drag_flag = 0;
 	tty->mouse_drag_update = NULL;
@@ -406,7 +406,7 @@ tty_stop_tty(struct tty *tty)
 	}
 	if (tty->mode & MODE_BRACKETPASTE)
 		tty_raw(tty, tty_term_string(tty->term, TTYC_DSBP));
-	if (*tty->ccolour != '\0')
+	if (tty->ccolour != -1)
 		tty_raw(tty, tty_term_string(tty->term, TTYC_CR));
 
 	tty_raw(tty, tty_term_string(tty->term, TTYC_CNORM));
@@ -451,7 +451,6 @@ void
 tty_free(struct tty *tty)
 {
 	tty_close(tty);
-	free(tty->ccolour);
 }
 
 void
@@ -650,24 +649,38 @@ tty_set_title(struct tty *tty, const char *title)
 }
 
 static void
-tty_force_cursor_colour(struct tty *tty, const char *ccolour)
+tty_force_cursor_colour(struct tty *tty, int c)
 {
-	if (*ccolour == '\0')
+	u_char	r, g, b;
+	char	s[13] = "";
+
+	if (c != -1)
+		c = colour_force_rgb(c);
+	if (c == tty->ccolour)
+		return;
+	if (c == -1)
 		tty_putcode(tty, TTYC_CR);
-	else
-		tty_putcode_ptr1(tty, TTYC_CS, ccolour);
-	free(tty->ccolour);
-	tty->ccolour = xstrdup(ccolour);
+	else {
+		colour_split_rgb(c, &r, &g, &b);
+		xsnprintf(s, sizeof s, "rgb:%02hhx/%02hhx/%02hhx", r, g, b);
+		tty_putcode_ptr1(tty, TTYC_CS, s);
+	}
+	tty->ccolour = c;
 }
 
 static void
 tty_update_cursor(struct tty *tty, int mode, int changed, struct screen *s)
 {
-	enum screen_cursor_style cstyle;
+	enum screen_cursor_style	cstyle;
+	int				ccolour;
 
 	/* Set cursor colour if changed. */
-	if (s != NULL && strcmp(s->ccolour, tty->ccolour) != 0)
-		tty_force_cursor_colour(tty, s->ccolour);
+	if (s != NULL) {
+		ccolour = s->ccolour;
+		if (s->ccolour == -1)
+			ccolour = s->default_ccolour;
+		tty_force_cursor_colour(tty, ccolour);
+	}
 
 	/* If cursor is off, set as invisible. */
 	if (~mode & MODE_CURSOR) {