1 /*
2  *  menubox.c -- implements the menu box
3  *
4  *  ORIGINAL AUTHOR: Savio Lam (lam836@cs.cuhk.hk)
5  *  MODIFIED FOR LINUX KERNEL CONFIG BY: William Roadcap (roadcapw@cfw.com)
6  *
7  *  This program is free software; you can redistribute it and/or
8  *  modify it under the terms of the GNU General Public License
9  *  as published by the Free Software Foundation; either version 2
10  *  of the License, or (at your option) any later version.
11  *
12  *  This program is distributed in the hope that it will be useful,
13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  *  GNU General Public License for more details.
16  *
17  *  You should have received a copy of the GNU General Public License
18  *  along with this program; if not, write to the Free Software
19  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20  */
21 
22 /*
23  *  Changes by Clifford Wolf (god@clifford.at)
24  *
25  *  [ 1998-06-13 ]
26  *
27  *    *)  A bugfix for the Page-Down problem
28  *
29  *    *)  Formerly when I used Page Down and Page Up, the cursor would be set
30  *        to the first position in the menu box.  Now lxdialog is a bit
31  *        smarter and works more like other menu systems (just have a look at
32  *        it).
33  *
34  *    *)  Formerly if I selected something my scrolling would be broken because
35  *        lxdialog is re-invoked by the Menuconfig shell script, can't
36  *        remember the last scrolling position, and just sets it so that the
37  *        cursor is at the bottom of the box.  Now it writes the temporary file
38  *        lxdialog.scrltmp which contains this information. The file is
39  *        deleted by lxdialog if the user leaves a submenu or enters a new
40  *        one, but it would be nice if Menuconfig could make another "rm -f"
41  *        just to be sure.  Just try it out - you will recognise a difference!
42  *
43  *  [ 1998-06-14 ]
44  *
45  *    *)  Now lxdialog is crash-safe against broken "lxdialog.scrltmp" files
46  *        and menus change their size on the fly.
47  *
48  *    *)  If for some reason the last scrolling position is not saved by
49  *        lxdialog, it sets the scrolling so that the selected item is in the
50  *        middle of the menu box, not at the bottom.
51  *
52  * 02 January 1999, Michael Elizabeth Chastain (mec@shout.net)
53  * Reset 'scroll' to 0 if the value from lxdialog.scrltmp is bogus.
54  * This fixes a bug in Menuconfig where using ' ' to descend into menus
55  * would leave mis-synchronized lxdialog.scrltmp files lying around,
56  * fscanf would read in 'scroll', and eventually that value would get used.
57  */
58 
59 #include "dialog.h"
60 
61 static int menu_width, item_x;
62 
63 /*
64  * Print menu item
65  */
66 static void do_print_item(WINDOW * win, const char *item, int line_y,
67 			  int selected, int hotkey)
68 {
69 	int j;
70 	char *menu_item = malloc(menu_width + 1);
71 
72 	strncpy(menu_item, item, menu_width - item_x);
73 	menu_item[menu_width - item_x] = '\0';
74 	j = first_alpha(menu_item, "YyNnMmHh");
75 
76 	/* Clear 'residue' of last item */
77 	wattrset(win, dlg.menubox.atr);
78 	wmove(win, line_y, 0);
79 #if OLD_NCURSES
80 	{
81 		int i;
82 		for (i = 0; i < menu_width; i++)
83 			waddch(win, ' ');
84 	}
85 #else
86 	wclrtoeol(win);
87 #endif
88 	wattrset(win, selected ? dlg.item_selected.atr : dlg.item.atr);
89 	mvwaddstr(win, line_y, item_x, menu_item);
90 	if (hotkey) {
91 		wattrset(win, selected ? dlg.tag_key_selected.atr
92 			 : dlg.tag_key.atr);
93 		mvwaddch(win, line_y, item_x + j, menu_item[j]);
94 	}
95 	if (selected) {
96 		wmove(win, line_y, item_x + 1);
97 	}
98 	free(menu_item);
99 	wrefresh(win);
100 }
101 
102 #define print_item(index, choice, selected)				\
103 do {									\
104 	item_set(index);						\
105 	do_print_item(menu, item_str(), choice, selected, !item_is_tag(':')); \
106 } while (0)
107 
108 /*
109  * Print the scroll indicators.
110  */
111 static void print_arrows(WINDOW * win, int item_no, int scroll, int y, int x,
112 			 int height)
113 {
114 	int cur_y, cur_x;
115 
116 	getyx(win, cur_y, cur_x);
117 
118 	wmove(win, y, x);
119 
120 	if (scroll > 0) {
121 		wattrset(win, dlg.uarrow.atr);
122 		waddch(win, ACS_UARROW);
123 		waddstr(win, "(-)");
124 	} else {
125 		wattrset(win, dlg.menubox.atr);
126 		waddch(win, ACS_HLINE);
127 		waddch(win, ACS_HLINE);
128 		waddch(win, ACS_HLINE);
129 		waddch(win, ACS_HLINE);
130 	}
131 
132 	y = y + height + 1;
133 	wmove(win, y, x);
134 	wrefresh(win);
135 
136 	if ((height < item_no) && (scroll + height < item_no)) {
137 		wattrset(win, dlg.darrow.atr);
138 		waddch(win, ACS_DARROW);
139 		waddstr(win, "(+)");
140 	} else {
141 		wattrset(win, dlg.menubox_border.atr);
142 		waddch(win, ACS_HLINE);
143 		waddch(win, ACS_HLINE);
144 		waddch(win, ACS_HLINE);
145 		waddch(win, ACS_HLINE);
146 	}
147 
148 	wmove(win, cur_y, cur_x);
149 	wrefresh(win);
150 }
151 
152 /*
153  * Display the termination buttons.
154  */
155 static void print_buttons(WINDOW * win, int height, int width, int selected)
156 {
157 	int x = width / 2 - 28;
158 	int y = height - 2;
159 
160 	print_button(win, gettext("Select"), y, x, selected == 0);
161 	print_button(win, gettext(" Exit "), y, x + 12, selected == 1);
162 	print_button(win, gettext(" Help "), y, x + 24, selected == 2);
163 	print_button(win, gettext(" Save "), y, x + 36, selected == 3);
164 	print_button(win, gettext(" Load "), y, x + 48, selected == 4);
165 
166 	wmove(win, y, x + 1 + 12 * selected);
167 	wrefresh(win);
168 }
169 
170 /* scroll up n lines (n may be negative) */
171 static void do_scroll(WINDOW *win, int *scroll, int n)
172 {
173 	/* Scroll menu up */
174 	scrollok(win, TRUE);
175 	wscrl(win, n);
176 	scrollok(win, FALSE);
177 	*scroll = *scroll + n;
178 	wrefresh(win);
179 }
180 
181 /*
182  * Display a menu for choosing among a number of options
183  */
184 int dialog_menu(const char *title, const char *prompt,
185 		const void *selected, int *s_scroll)
186 {
187 	int i, j, x, y, box_x, box_y;
188 	int height, width, menu_height;
189 	int key = 0, button = 0, scroll = 0, choice = 0;
190 	int first_item =  0, max_choice;
191 	WINDOW *dialog, *menu;
192 
193 do_resize:
194 	height = getmaxy(stdscr);
195 	width = getmaxx(stdscr);
196 	if (height < MENUBOX_HEIGTH_MIN || width < MENUBOX_WIDTH_MIN)
197 		return -ERRDISPLAYTOOSMALL;
198 
199 	height -= 4;
200 	width  -= 5;
201 	menu_height = height - 10;
202 
203 	max_choice = MIN(menu_height, item_count());
204 
205 	/* center dialog box on screen */
206 	x = (getmaxx(stdscr) - width) / 2;
207 	y = (getmaxy(stdscr) - height) / 2;
208 
209 	draw_shadow(stdscr, y, x, height, width);
210 
211 	dialog = newwin(height, width, y, x);
212 	keypad(dialog, TRUE);
213 
214 	draw_box(dialog, 0, 0, height, width,
215 		 dlg.dialog.atr, dlg.border.atr);
216 	wattrset(dialog, dlg.border.atr);
217 	mvwaddch(dialog, height - 3, 0, ACS_LTEE);
218 	for (i = 0; i < width - 2; i++)
219 		waddch(dialog, ACS_HLINE);
220 	wattrset(dialog, dlg.dialog.atr);
221 	wbkgdset(dialog, dlg.dialog.atr & A_COLOR);
222 	waddch(dialog, ACS_RTEE);
223 
224 	print_title(dialog, title, width);
225 
226 	wattrset(dialog, dlg.dialog.atr);
227 	print_autowrap(dialog, prompt, width - 2, 1, 3);
228 
229 	menu_width = width - 6;
230 	box_y = height - menu_height - 5;
231 	box_x = (width - menu_width) / 2 - 1;
232 
233 	/* create new window for the menu */
234 	menu = subwin(dialog, menu_height, menu_width,
235 		      y + box_y + 1, x + box_x + 1);
236 	keypad(menu, TRUE);
237 
238 	/* draw a box around the menu items */
239 	draw_box(dialog, box_y, box_x, menu_height + 2, menu_width + 2,
240 		 dlg.menubox_border.atr, dlg.menubox.atr);
241 
242 	if (menu_width >= 80)
243 		item_x = (menu_width - 70) / 2;
244 	else
245 		item_x = 4;
246 
247 	/* Set choice to default item */
248 	item_foreach()
249 		if (selected && (selected == item_data()))
250 			choice = item_n();
251 	/* get the saved scroll info */
252 	scroll = *s_scroll;
253 	if ((scroll <= choice) && (scroll + max_choice > choice) &&
254 	   (scroll >= 0) && (scroll + max_choice <= item_count())) {
255 		first_item = scroll;
256 		choice = choice - scroll;
257 	} else {
258 		scroll = 0;
259 	}
260 	if ((choice >= max_choice)) {
261 		if (choice >= item_count() - max_choice / 2)
262 			scroll = first_item = item_count() - max_choice;
263 		else
264 			scroll = first_item = choice - max_choice / 2;
265 		choice = choice - scroll;
266 	}
267 
268 	/* Print the menu */
269 	for (i = 0; i < max_choice; i++) {
270 		print_item(first_item + i, i, i == choice);
271 	}
272 
273 	wnoutrefresh(menu);
274 
275 	print_arrows(dialog, item_count(), scroll,
276 		     box_y, box_x + item_x + 1, menu_height);
277 
278 	print_buttons(dialog, height, width, 0);
279 	wmove(menu, choice, item_x + 1);
280 	wrefresh(menu);
281 
282 	while (key != KEY_ESC) {
283 		key = wgetch(menu);
284 
285 		if (key < 256 && isalpha(key))
286 			key = tolower(key);
287 
288 		if (strchr("ynmh", key))
289 			i = max_choice;
290 		else {
291 			for (i = choice + 1; i < max_choice; i++) {
292 				item_set(scroll + i);
293 				j = first_alpha(item_str(), "YyNnMmHh");
294 				if (key == tolower(item_str()[j]))
295 					break;
296 			}
297 			if (i == max_choice)
298 				for (i = 0; i < max_choice; i++) {
299 					item_set(scroll + i);
300 					j = first_alpha(item_str(), "YyNnMmHh");
301 					if (key == tolower(item_str()[j]))
302 						break;
303 				}
304 		}
305 
306 		if (item_count() != 0 &&
307 		    (i < max_choice ||
308 		     key == KEY_UP || key == KEY_DOWN ||
309 		     key == '-' || key == '+' ||
310 		     key == KEY_PPAGE || key == KEY_NPAGE)) {
311 			/* Remove highligt of current item */
312 			print_item(scroll + choice, choice, FALSE);
313 
314 			if (key == KEY_UP || key == '-') {
315 				if (choice < 2 && scroll) {
316 					/* Scroll menu down */
317 					do_scroll(menu, &scroll, -1);
318 
319 					print_item(scroll, 0, FALSE);
320 				} else
321 					choice = MAX(choice - 1, 0);
322 
323 			} else if (key == KEY_DOWN || key == '+') {
324 				print_item(scroll+choice, choice, FALSE);
325 
326 				if ((choice > max_choice - 3) &&
327 				    (scroll + max_choice < item_count())) {
328 					/* Scroll menu up */
329 					do_scroll(menu, &scroll, 1);
330 
331 					print_item(scroll+max_choice - 1,
332 						   max_choice - 1, FALSE);
333 				} else
334 					choice = MIN(choice + 1, max_choice - 1);
335 
336 			} else if (key == KEY_PPAGE) {
337 				scrollok(menu, TRUE);
338 				for (i = 0; (i < max_choice); i++) {
339 					if (scroll > 0) {
340 						do_scroll(menu, &scroll, -1);
341 						print_item(scroll, 0, FALSE);
342 					} else {
343 						if (choice > 0)
344 							choice--;
345 					}
346 				}
347 
348 			} else if (key == KEY_NPAGE) {
349 				for (i = 0; (i < max_choice); i++) {
350 					if (scroll + max_choice < item_count()) {
351 						do_scroll(menu, &scroll, 1);
352 						print_item(scroll+max_choice-1,
353 							   max_choice - 1, FALSE);
354 					} else {
355 						if (choice + 1 < max_choice)
356 							choice++;
357 					}
358 				}
359 			} else
360 				choice = i;
361 
362 			print_item(scroll + choice, choice, TRUE);
363 
364 			print_arrows(dialog, item_count(), scroll,
365 				     box_y, box_x + item_x + 1, menu_height);
366 
367 			wnoutrefresh(dialog);
368 			wrefresh(menu);
369 
370 			continue;	/* wait for another key press */
371 		}
372 
373 		switch (key) {
374 		case KEY_LEFT:
375 		case TAB:
376 		case KEY_RIGHT:
377 			button = ((key == KEY_LEFT ? --button : ++button) < 0)
378 			    ? 4 : (button > 4 ? 0 : button);
379 
380 			print_buttons(dialog, height, width, button);
381 			wrefresh(menu);
382 			break;
383 		case ' ':
384 		case 's':
385 		case 'y':
386 		case 'n':
387 		case 'm':
388 		case '/':
389 		case 'h':
390 		case '?':
391 		case 'z':
392 		case '\n':
393 			/* save scroll info */
394 			*s_scroll = scroll;
395 			delwin(menu);
396 			delwin(dialog);
397 			item_set(scroll + choice);
398 			item_set_selected(1);
399 			switch (key) {
400 			case 'h':
401 			case '?':
402 				return 2;
403 			case 's':
404 			case 'y':
405 				return 5;
406 			case 'n':
407 				return 6;
408 			case 'm':
409 				return 7;
410 			case ' ':
411 				return 8;
412 			case '/':
413 				return 9;
414 			case 'z':
415 				return 10;
416 			case '\n':
417 				return button;
418 			}
419 			return 0;
420 		case 'e':
421 		case 'x':
422 			key = KEY_ESC;
423 			break;
424 		case KEY_ESC:
425 			key = on_key_esc(menu);
426 			break;
427 		case KEY_RESIZE:
428 			on_key_resize();
429 			delwin(menu);
430 			delwin(dialog);
431 			goto do_resize;
432 		}
433 	}
434 	delwin(menu);
435 	delwin(dialog);
436 	return key;		/* ESC pressed */
437 }
438