[menu] Add menu user interface

Inspired-by: Robin Smidsrød <robin@smidsrod.no>
Tested-by: Robin Smidsrød <robin@smidsrod.no>
Signed-off-by: Michael Brown <mcb30@ipxe.org>

src/hci/tui/menu_ui.c

+/*
+ * Copyright (C) 2012 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+/** @file
+ *
+ * Menu interface
+ *
+ */
+
+#include <string.h>
+#include <errno.h>
+#include <curses.h>
+#include <ipxe/keys.h>
+#include <ipxe/timer.h>
+#include <ipxe/console.h>
+#include <ipxe/menu.h>
+
+/* Colour pairs */
+#define CPAIR_NORMAL	1
+#define CPAIR_SELECT	2
+#define CPAIR_SEPARATOR	3
+
+/* Screen layout */
+#define TITLE_ROW	1
+#define MENU_ROW	3
+#define MENU_COL	1
+#define MENU_ROWS	18
+#define MENU_COLS	78
+#define MENU_PAD	2
+
+/** A menu user interface */
+struct menu_ui {
+	/** Menu */
+	struct menu *menu;
+	/** Number of menu items */
+	int count;
+	/** Currently selected item */
+	int selected;
+	/** First visible item */
+	int first_visible;
+	/** Timeout (0=indefinite) */
+	unsigned long timeout;
+};
+
+/**
+ * Return a numbered menu item
+ *
+ * @v menu		Menu
+ * @v index		Index
+ * @ret item		Menu item, or NULL
+ */
+static struct menu_item * menu_item ( struct menu *menu, unsigned int index ) {
+	struct menu_item *item;
+
+	list_for_each_entry ( item, &menu->items, list ) {
+		if ( index-- == 0 )
+			return item;
+	}
+
+	return NULL;
+}
+
+/**
+ * Draw a numbered menu item
+ *
+ * @v ui		Menu user interface
+ * @v index		Index
+ */
+static void draw_menu_item ( struct menu_ui *ui, int index ) {
+	struct menu_item *item;
+	unsigned int row_offset;
+	char buf[ MENU_COLS + 1 /* NUL */ ];
+	char timeout_buf[6]; /* "(xxx)" + NUL */
+	size_t timeout_len;
+	size_t max_len;
+	size_t len;
+
+	/* Move to start of row */
+	row_offset = ( index - ui->first_visible );
+	move ( ( MENU_ROW + row_offset ), MENU_COL );
+
+	/* Get menu item */
+	item = menu_item ( ui->menu, index );
+	if ( item ) {
+
+		/* Draw separators in a different colour */
+		if ( ! item->label )
+			color_set ( CPAIR_SEPARATOR, NULL );
+
+		/* Highlight if this is the selected item */
+		if ( index == ui->selected ) {
+			color_set ( CPAIR_SELECT, NULL );
+			attron ( A_BOLD );
+		}
+
+		/* Construct row */
+		memset ( buf, ' ', ( sizeof ( buf ) - 1 ) );
+		buf[ sizeof ( buf ) -1 ] = '\0';
+		len = strlen ( item->text );
+		max_len = ( sizeof ( buf ) - 1 /* NUL */ - ( 2 * MENU_PAD ) );
+		if ( len > max_len )
+			len = max_len;
+		memcpy ( ( buf + MENU_PAD ), item->text, len );
+
+		/* Add timeout if applicable */
+		timeout_len =
+			snprintf ( timeout_buf, sizeof ( timeout_buf ), "(%ld)",
+				   ( ( ui->timeout + TICKS_PER_SEC - 1 ) /
+				     TICKS_PER_SEC ) );
+		if ( ( index == ui->selected ) && ( ui->timeout != 0 ) ) {
+			memcpy ( ( buf + MENU_COLS - MENU_PAD - timeout_len ),
+				 timeout_buf, timeout_len );
+		}
+
+		/* Print row */
+		printw ( "%s", buf );
+
+		/* Reset attributes */
+		color_set ( CPAIR_NORMAL, NULL );
+		attroff ( A_BOLD );
+
+	} else {
+		/* Clear row if there is no corresponding menu item */
+		clrtoeol();
+	}
+
+	/* Move cursor back to start of row */
+	move ( ( MENU_ROW + row_offset ), MENU_COL );
+}
+
+/**
+ * Draw the current block of menu items
+ *
+ * @v ui		Menu user interface
+ */
+static void draw_menu_items ( struct menu_ui *ui ) {
+	unsigned int i;
+
+	/* Jump scroll to correct point in list */
+	while ( ui->first_visible < ui->selected )
+		ui->first_visible += MENU_ROWS;
+	while ( ui->first_visible > ui->selected )
+		ui->first_visible -= MENU_ROWS;
+
+	/* Draw ellipses before and/or after the list as necessary */
+	color_set ( CPAIR_SEPARATOR, NULL );
+	mvaddstr ( ( MENU_ROW - 1 ), ( MENU_COL + MENU_PAD ),
+		   ( ( ui->first_visible > 0 ) ? "..." : "   " ) );
+	mvaddstr ( ( MENU_ROW + MENU_ROWS ), ( MENU_COL + MENU_PAD ),
+		   ( ( ( ui->first_visible + MENU_ROWS ) < ui->count ) ?
+		     "..." : "   " ) );
+	color_set ( CPAIR_NORMAL, NULL );
+
+	/* Draw visible items */
+	for ( i = 0 ; i < MENU_ROWS ; i++ )
+		draw_menu_item ( ui, ( ui->first_visible + i ) );
+}
+
+/**
+ * Menu main loop
+ *
+ * @v ui		Menu user interface
+ * @ret selected	Selected item
+ * @ret rc		Return status code
+ */
+static int menu_loop ( struct menu_ui *ui, struct menu_item **selected ) {
+	struct menu_item *item;
+	unsigned long timeout;
+	unsigned int delta;
+	int current;
+	int key;
+	int i;
+	int move;
+	int chosen = 0;
+	int rc = 0;
+
+	do {
+		/* Record current selection */
+		current = ui->selected;
+
+		/* Calculate timeout as remainder of current second */
+		timeout = ( ui->timeout % TICKS_PER_SEC );
+		if ( ( timeout == 0 ) && ( ui->timeout != 0 ) )
+			timeout = TICKS_PER_SEC;
+		ui->timeout -= timeout;
+
+		/* Get key */
+		move = 0;
+		key = getkey ( timeout );
+		if ( key < 0 ) {
+			/* Choose default if we finally time out */
+			if ( ui->timeout == 0 )
+				chosen = 1;
+		} else {
+			/* Cancel any timeout */
+			ui->timeout = 0;
+
+			/* Handle key */
+			switch ( key ) {
+			case KEY_UP:
+				move = -1;
+				break;
+			case KEY_DOWN:
+				move = +1;
+				break;
+			case KEY_PPAGE:
+				move = ( ui->first_visible - ui->selected - 1 );
+				break;
+			case KEY_NPAGE:
+				move = ( ui->first_visible - ui->selected
+					 + MENU_ROWS );
+				break;
+			case KEY_HOME:
+				move = -ui->count;
+				break;
+			case KEY_END:
+				move = +ui->count;
+				break;
+			case ESC:
+			case CTRL_C:
+				rc = -ECANCELED;
+				break;
+			case CR:
+			case LF:
+				chosen = 1;
+				break;
+			default:
+				i = 0;
+				list_for_each_entry ( item, &ui->menu->items,
+						      list ) {
+					if ( item->shortcut == key ) {
+						ui->selected = i;
+						chosen = 1;
+						break;
+					}
+					i++;
+				}
+				break;
+			}
+		}
+
+		/* Move selection, if applicable */
+		while ( move ) {
+			ui->selected += move;
+			if ( ui->selected < 0 ) {
+				ui->selected = 0;
+				move = +1;
+			} else if ( ui->selected >= ui->count ) {
+				ui->selected = ( ui->count - 1 );
+				move = -1;
+			}
+			item = menu_item ( ui->menu, ui->selected );
+			if ( item->label )
+				break;
+			move = ( ( move > 0 ) ? +1 : -1 );
+		}
+
+		/* Redraw selection if necessary */
+		if ( ( ui->selected != current ) || ( timeout != 0 ) ) {
+			draw_menu_item ( ui, current );
+			delta = ( ui->selected - ui->first_visible );
+			if ( delta >= MENU_ROWS )
+				draw_menu_items ( ui );
+			draw_menu_item ( ui, ui->selected );
+		}
+
+		/* Refuse to choose unlabelled items (i.e. separators) */
+		item = menu_item ( ui->menu, ui->selected );
+		if ( ! item->label )
+			chosen = 0;
+
+		/* Record selection */
+		*selected = item;
+
+	} while ( ( rc == 0 ) && ! chosen );
+
+	return rc;
+}
+
+/**
+ * Show menu
+ *
+ * @v menu		Menu
+ * @v wait_ms		Time to wait, in milliseconds (0=indefinite)
+ * @ret selected	Selected item
+ * @ret rc		Return status code
+ */
+int show_menu ( struct menu *menu, unsigned int timeout_ms,
+		struct menu_item **selected ) {
+	struct menu_item *item;
+	struct menu_ui ui;
+	int labelled_count = 0;
+	int rc;
+
+	/* Initialise UI */
+	memset ( &ui, 0, sizeof ( ui ) );
+	ui.menu = menu;
+	ui.timeout = ( ( timeout_ms * TICKS_PER_SEC ) / 1000 );
+	list_for_each_entry ( item, &menu->items, list ) {
+		if ( item->label ) {
+			labelled_count++;
+			if ( ! ui.selected )
+				ui.selected = ui.count;
+			if ( item->is_default )
+				ui.selected = ui.count;
+		}
+		ui.count++;
+	}
+	if ( ! labelled_count ) {
+		/* Menus with no labelled items cannot be selected
+		 * from, and will seriously confuse the navigation
+		 * logic.  Refuse to display any such menus.
+		 */
+		return -ENOENT;
+	}
+
+	/* Initialise screen */
+	initscr();
+	start_color();
+	init_pair ( CPAIR_NORMAL, COLOR_WHITE, COLOR_BLUE );
+	init_pair ( CPAIR_SELECT, COLOR_WHITE, COLOR_RED );
+	init_pair ( CPAIR_SEPARATOR, COLOR_CYAN, COLOR_BLUE );
+	color_set ( CPAIR_NORMAL, NULL );
+	erase();
+
+	/* Draw initial content */
+	attron ( A_BOLD );
+	mvprintw ( TITLE_ROW, ( ( COLS - strlen ( ui.menu->title ) ) / 2 ),
+		   "%s", ui.menu->title );
+	attroff ( A_BOLD );
+	draw_menu_items ( &ui );
+	draw_menu_item ( &ui, ui.selected );
+
+	/* Enter main loop */
+	rc = menu_loop ( &ui, selected );
+	assert ( *selected );
+
+	/* Clear screen */
+	endwin();
+
+	return rc;
+}

src/include/ipxe/errfile.h

 #define ERRFILE_x509_test	      ( ERRFILE_OTHER | 0x00290000 )
 #define ERRFILE_cms		      ( ERRFILE_OTHER | 0x002a0000 )
 #define ERRFILE_imgtrust	      ( ERRFILE_OTHER | 0x002b0000 )
+#define ERRFILE_menu_ui		      ( ERRFILE_OTHER | 0x002c0000 )
 
 /** @} */
 

src/include/ipxe/menu.h

 					  int is_default );
 extern void destroy_menu ( struct menu *menu );
 extern struct menu * find_menu ( const char *name );
+extern int show_menu ( struct menu *menu, unsigned int timeout_ms,
+		       struct menu_item **selected );
 
 #endif /* _IPXE_MENU_H */