menuconfig: Add "breadcrumbs" navigation aid

Displays a trail of the menu entries used to get to the current menu.

Signed-off-by: Benjamin Poirier <bpoirier@suse.de>
Tested-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
[yann.morin.1998@free.fr: small, trivial code re-ordering]
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>

scripts/kconfig/lxdialog/dialog.h

@@ -106,8 +106,14 @@ struct dialog_color {
 	int hl;		/* highlight this item */
 };
 
+struct subtitle_list {
+	struct subtitle_list *next;
+	const char *text;
+};
+
 struct dialog_info {
 	const char *backtitle;
+	struct subtitle_list *subtitles;
 	struct dialog_color screen;
 	struct dialog_color shadow;
 	struct dialog_color dialog;
@@ -196,6 +202,7 @@ int on_key_resize(void);
 
 int init_dialog(const char *backtitle);
 void set_dialog_backtitle(const char *backtitle);
+void set_dialog_subtitles(struct subtitle_list *subtitles);
 void end_dialog(int x, int y);
 void attr_clear(WINDOW * win, int height, int width, chtype attr);
 void dialog_clear(void);

scripts/kconfig/lxdialog/util.c

@@ -257,12 +257,48 @@ void dialog_clear(void)
 	attr_clear(stdscr, LINES, COLS, dlg.screen.atr);
 	/* Display background title if it exists ... - SLH */
 	if (dlg.backtitle != NULL) {
-		int i;
+		int i, len = 0, skip = 0;
+		struct subtitle_list *pos;
 
 		wattrset(stdscr, dlg.screen.atr);
 		mvwaddstr(stdscr, 0, 1, (char *)dlg.backtitle);
+
+		for (pos = dlg.subtitles; pos != NULL; pos = pos->next) {
+			/* 3 is for the arrow and spaces */
+			len += strlen(pos->text) + 3;
+		}
+
 		wmove(stdscr, 1, 1);
-		for (i = 1; i < COLS - 1; i++)
+		if (len > COLS - 2) {
+			const char *ellipsis = "[...] ";
+			waddstr(stdscr, ellipsis);
+			skip = len - (COLS - 2 - strlen(ellipsis));
+		}
+
+		for (pos = dlg.subtitles; pos != NULL; pos = pos->next) {
+			if (skip == 0)
+				waddch(stdscr, ACS_RARROW);
+			else
+				skip--;
+
+			if (skip == 0)
+				waddch(stdscr, ' ');
+			else
+				skip--;
+
+			if (skip < strlen(pos->text)) {
+				waddstr(stdscr, pos->text + skip);
+				skip = 0;
+			} else
+				skip -= strlen(pos->text);
+
+			if (skip == 0)
+				waddch(stdscr, ' ');
+			else
+				skip--;
+		}
+
+		for (i = len + 1; i < COLS - 1; i++)
 			waddch(stdscr, ACS_HLINE);
 	}
 	wnoutrefresh(stdscr);
@@ -302,6 +338,11 @@ void set_dialog_backtitle(const char *backtitle)
 	dlg.backtitle = backtitle;
 }
 
+void set_dialog_subtitles(struct subtitle_list *subtitles)
+{
+	dlg.subtitles = subtitles;
+}
+
 /*
  * End using dialog functions.
  */