[hci] Provide a general concept of a text widget set

Create a generic abstraction of a text widget, refactor the existing
editable text box widget to use this abstraction, add an
implementation of a non-editable text label widget, and generalise the
login user interface to use this generic widget abstraction.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

src/include/ipxe/editbox.h

@@ -11,51 +11,39 @@ FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 
 #include <curses.h>
 #include <ipxe/editstring.h>
+#include <ipxe/widget.h>
 
 /** An editable text box widget */
 struct edit_box {
+	/** Text widget */
+	struct widget widget;
 	/** Editable string */
 	struct edit_string string;
-	/** Containing window */
-	WINDOW *win;
-	/** Row */
-	unsigned int row;
-	/** Starting column */
-	unsigned int col;
-	/** Width */
-	unsigned int width;
 	/** First displayed character */
 	unsigned int first;
-	/** Flags */
-	unsigned int flags;
 };
 
-/** Editable text box widget flags */
-enum edit_box_flags {
-	/** Show stars instead of contents (for password widgets) */
-	EDITBOX_STARS = 0x0001,
-};
-
-extern void init_editbox ( struct edit_box *box, char **buf,
-			   WINDOW *win, unsigned int row, unsigned int col,
-			   unsigned int width, unsigned int flags )
-			   __attribute__ (( nonnull (1, 2) ));
-extern void draw_editbox ( struct edit_box *box ) __nonnull;
-static inline int edit_editbox ( struct edit_box *box, int key ) __nonnull;
+extern struct widget_operations editbox_operations;
 
 /**
- * Edit text box widget
+ * Initialise text box widget
  *
  * @v box		Editable text box widget
- * @v key		Key pressed by user
- * @ret key		Key returned to application, or zero
- *
- * You must call draw_editbox() to update the display after calling
- * edit_editbox().
- *
+ * @v row		Row
+ * @v col		Starting column
+ * @v width		Width
+ * @v flags		Flags
+ * @v buf		Dynamically allocated string buffer
  */
-static inline int edit_editbox ( struct edit_box *box, int key ) {
-	return edit_string ( &box->string, key );
+static inline __attribute__ (( always_inline )) void
+init_editbox ( struct edit_box *box, unsigned int row, unsigned int col,
+	       unsigned int width, unsigned int flags, char **buf ) {
+
+	init_widget ( &box->widget, &editbox_operations, row, col,
+		      width, ( flags | WIDGET_EDITABLE ) );
+	init_editstring ( &box->string, buf );
+	if ( *buf )
+		box->string.cursor = strlen ( *buf );
 }
 
 #endif /* _IPXE_EDITBOX_H */

src/include/ipxe/errfile.h

@@ -417,6 +417,7 @@ FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 #define ERRFILE_x25519		      ( ERRFILE_OTHER | 0x005f0000 )
 #define ERRFILE_des		      ( ERRFILE_OTHER | 0x00600000 )
 #define ERRFILE_editstring	      ( ERRFILE_OTHER | 0x00610000 )
+#define ERRFILE_widget_ui	      ( ERRFILE_OTHER | 0x00620000 )
 
 /** @} */
 

src/include/ipxe/label.h

@@ -0,0 +1,42 @@
+#ifndef _IPXE_LABEL_H
+#define _IPXE_LABEL_H
+
+/** @file
+ *
+ * Text label widget
+ *
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
+
+#include <curses.h>
+#include <ipxe/widget.h>
+
+/** A text label widget */
+struct label {
+	/** Text widget */
+	struct widget widget;
+	/** Label text */
+	const char *text;
+};
+
+extern struct widget_operations label_operations;
+
+/**
+ * Initialise text label widget
+ *
+ * @v label		Text label widget
+ * @v row		Row
+ * @v col		Starting column
+ * @v width		Width
+ * @v text		Label text
+ */
+static inline __attribute__ (( always_inline )) void
+init_label ( struct label *label, unsigned int row, unsigned int col,
+	     unsigned int width, const char *text ) {
+
+	init_widget ( &label->widget, &label_operations, row, col, width, 0 );
+	label->text = text;
+}
+
+#endif /* _IPXE_LABEL_H */

src/include/ipxe/widget.h

@@ -0,0 +1,151 @@
+#ifndef _IPXE_WIDGET_H
+#define _IPXE_WIDGET_H
+
+/** @file
+ *
+ * Text widgets
+ *
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
+
+#include <curses.h>
+#include <ipxe/list.h>
+
+/** A text widget set */
+struct widgets {
+	/** List of widgets (in tab order) */
+	struct list_head list;
+	/** Containing window */
+	WINDOW *win;
+};
+
+/** A text widget */
+struct widget {
+	/** List of widgets (in tab order) */
+	struct list_head list;
+	/** Widget operations */
+	struct widget_operations *op;
+
+	/** Row */
+	unsigned int row;
+	/** Starting column */
+	unsigned int col;
+	/** Width */
+	unsigned int width;
+	/** Flags */
+	unsigned int flags;
+};
+
+/** Text widget flags */
+enum widget_flags {
+	/** Widget may have input focus */
+	WIDGET_EDITABLE = 0x0001,
+	/** Widget contains a secret */
+	WIDGET_SECRET = 0x0002,
+};
+
+/** Text widget operations */
+struct widget_operations {
+	/**
+	 * Draw widget
+	 *
+	 * @v widgets		Text widget set
+	 * @v widget		Text widget
+	 */
+	void ( * draw ) ( struct widgets *widgets, struct widget *widget );
+	/**
+	 * Edit widget
+	 *
+	 * @v widgets		Text widget set
+	 * @v widget		Text widget
+	 * @v key		Key pressed by user
+	 * @ret key		Key returned to application, or zero
+	 *
+	 * This will not update the display: you must call the draw()
+	 * method to ensure that any changes to an editable widget are
+	 * displayed to the user.
+	 */
+	int ( * edit ) ( struct widgets *widgets, struct widget *widget,
+			 int key );
+};
+
+/**
+ * Initialise text widget set
+ *
+ * @v widgets		Text widget set
+ * @v win		Containing window
+ */
+static inline __attribute__ (( always_inline )) void
+init_widgets ( struct widgets *widgets, WINDOW *win ) {
+
+	INIT_LIST_HEAD ( &widgets->list );
+	widgets->win = ( win ? win : stdscr );
+}
+
+/**
+ * Initialise text widget
+ *
+ * @v widget		Text widget
+ * @v op		Text widget operations
+ * @v row		Row
+ * @v col		Starting column
+ * @v width		Width
+ */
+static inline __attribute__ (( always_inline )) void
+init_widget ( struct widget *widget, struct widget_operations *op,
+	      unsigned int row, unsigned int col, unsigned int width,
+	      unsigned int flags ) {
+
+	widget->op = op;
+	widget->row = row;
+	widget->col = col;
+	widget->width = width;
+	widget->flags = flags;
+}
+
+/**
+ * Append text widget
+ *
+ * @v widgets		Text widget set
+ * @v widget		Text widget
+ */
+static inline __attribute__ (( always_inline )) void
+add_widget ( struct widgets *widgets, struct widget *widget ) {
+
+	list_add_tail ( &widget->list, &widgets->list );
+}
+
+/**
+ * Draw text widget
+ *
+ * @v widgets		Text widget set
+ * @v widget		Text widget
+ */
+static inline __attribute__ (( always_inline )) void
+draw_widget ( struct widgets *widgets, struct widget *widget ) {
+
+	widget->op->draw ( widgets, widget );
+}
+
+/**
+ * Edit text widget
+ *
+ * @v widgets		Text widget set
+ * @v widget		Text widget
+ * @v key		Key pressed by user
+ * @ret key		Key returned to application, or zero
+ *
+ * This will not update the display: you must call draw_widget() to
+ * ensure that any changes to an editable widget are displayed to the
+ * user.
+ */
+static inline __attribute__ (( always_inline )) int
+edit_widget ( struct widgets *widgets, struct widget *widget, int key ) {
+
+	return widget->op->edit ( widgets, widget, key );
+}
+
+extern int widget_ui ( struct widgets *widgets );
+
+#endif /* _IPXE_WIDGET_H */