util/kconfig/lxdialog/menubox.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *  menubox.c -- implements the menu box
   4  *
   5  *  ORIGINAL AUTHOR: Savio Lam (lam836@cs.cuhk.hk)
   6  *  MODIFIED FOR LINUX KERNEL CONFIG BY: William Roadcap (roadcapw@cfw.com)
   7  */
   8
   9 /*
  10  *  Changes by Clifford Wolf (god@clifford.at)
  11  *
  12  *  [ 1998-06-13 ]
  13  *
  14  *    *)  A bugfix for the Page-Down problem
  15  *
  16  *    *)  Formerly when I used Page Down and Page Up, the cursor would be set
  17  *        to the first position in the menu box.  Now lxdialog is a bit
  18  *        smarter and works more like other menu systems (just have a look at
  19  *        it).
  20  *
  21  *    *)  Formerly if I selected something my scrolling would be broken because
  22  *        lxdialog is re-invoked by the Menuconfig shell script, can't
  23  *        remember the last scrolling position, and just sets it so that the
  24  *        cursor is at the bottom of the box.  Now it writes the temporary file
  25  *        lxdialog.scrltmp which contains this information. The file is
  26  *        deleted by lxdialog if the user leaves a submenu or enters a new
  27  *        one, but it would be nice if Menuconfig could make another "rm -f"
  28  *        just to be sure.  Just try it out - you will recognise a difference!
  29  *
  30  *  [ 1998-06-14 ]
  31  *
  32  *    *)  Now lxdialog is crash-safe against broken "lxdialog.scrltmp" files
  33  *        and menus change their size on the fly.
  34  *
  35  *    *)  If for some reason the last scrolling position is not saved by
  36  *        lxdialog, it sets the scrolling so that the selected item is in the
  37  *        middle of the menu box, not at the bottom.
  38  *
  39  * 02 January 1999, Michael Elizabeth Chastain (mec@shout.net)
  40  * Reset 'scroll' to 0 if the value from lxdialog.scrltmp is bogus.
  41  * This fixes a bug in Menuconfig where using ' ' to descend into menus
  42  * would leave mis-synchronized lxdialog.scrltmp files lying around,
  43  * fscanf would read in 'scroll', and eventually that value would get used.
  44  */
  45
  46 #include "dialog.h"
  47
  48 static int menu_width, item_x;
  49
  50 /*
  51  * Print menu item
  52  */
  53 static void do_print_item(WINDOW * win, const char *item, int line_y,
  54                           int selected, int hotkey)
  55 {
  56         int j;
  57         char *menu_item = malloc(menu_width + 1);
  58
  59         strncpy(menu_item, item, menu_width - item_x);
  60         menu_item[menu_width - item_x] = '\0';
  61         j = first_alpha(menu_item, "YyNnMmHh");
  62
  63         /* Clear 'residue' of last item */
  64         wattrset(win, dlg.menubox.atr);
  65         wmove(win, line_y, 0);
  66         wclrtoeol(win);
  67         wattrset(win, selected ? dlg.item_selected.atr : dlg.item.atr);
  68         mvwaddstr(win, line_y, item_x, menu_item);
  69         if (hotkey) {
  70                 wattrset(win, selected ? dlg.tag_key_selected.atr
  71                          : dlg.tag_key.atr);
  72                 mvwaddch(win, line_y, item_x + j, menu_item[j]);
  73         }
  74         if (selected) {
  75                 wmove(win, line_y, item_x + 1);
  76         }
  77         free(menu_item);
  78         wrefresh(win);
  79 }
  80
  81 #define print_item(index, choice, selected)                             \
  82 do {                                                                    \
  83         item_set(index);                                                \
  84         do_print_item(menu, item_str(), choice, selected, !item_is_tag(':')); \
  85 } while (0)
  86
  87 /*
  88  * Print the scroll indicators.
  89  */
  90 static void print_arrows(WINDOW * win, int item_no, int scroll, int y, int x,
  91                          int height)
  92 {
  93         int cur_y, cur_x;
  94
  95         getyx(win, cur_y, cur_x);
  96
  97         wmove(win, y, x);
  98
  99         if (scroll > 0) {
 100                 wattrset(win, dlg.uarrow.atr);
 101                 waddch(win, ACS_UARROW);
 102                 waddstr(win, "(-)");
 103         } else {
 104                 wattrset(win, dlg.menubox.atr);
 105                 waddch(win, ACS_HLINE);
 106                 waddch(win, ACS_HLINE);
 107                 waddch(win, ACS_HLINE);
 108                 waddch(win, ACS_HLINE);
 109         }
 110
 111         y = y + height + 1;
 112         wmove(win, y, x);
 113         wrefresh(win);
 114
 115         if ((height < item_no) && (scroll + height < item_no)) {
 116                 wattrset(win, dlg.darrow.atr);
 117                 waddch(win, ACS_DARROW);
 118                 waddstr(win, "(+)");
 119         } else {
 120                 wattrset(win, dlg.menubox_border.atr);
 121                 waddch(win, ACS_HLINE);
 122                 waddch(win, ACS_HLINE);
 123                 waddch(win, ACS_HLINE);
 124                 waddch(win, ACS_HLINE);
 125         }
 126
 127         wmove(win, cur_y, cur_x);
 128         wrefresh(win);
 129 }
 130
 131 /*
 132  * Display the termination buttons.
 133  */
 134 static void print_buttons(WINDOW * win, int height, int width, int selected)
 135 {
 136         int x = width / 2 - 28;
 137         int y = height - 2;
 138
 139         print_button(win, "Select", y, x, selected == 0);
 140         print_button(win, " Exit ", y, x + 12, selected == 1);
 141         print_button(win, " Help ", y, x + 24, selected == 2);
 142         print_button(win, " Save ", y, x + 36, selected == 3);
 143         print_button(win, " Load ", y, x + 48, selected == 4);
 144
 145         wmove(win, y, x + 1 + 12 * selected);
 146         wrefresh(win);
 147 }
 148
 149 /* scroll up n lines (n may be negative) */
 150 static void do_scroll(WINDOW *win, int *scroll, int n)
 151 {
 152         /* Scroll menu up */
 153         scrollok(win, TRUE);
 154         wscrl(win, n);
 155         scrollok(win, FALSE);
 156         *scroll = *scroll + n;
 157         wrefresh(win);
 158 }
 159
 160 /*
 161  * Display a menu for choosing among a number of options
 162  */
 163 int dialog_menu(const char *title, const char *prompt,
 164                 const void *selected, int *s_scroll)
 165 {
 166         int i, j, x, y, box_x, box_y;
 167         int height, width, menu_height;
 168         int key = 0, button = 0, scroll = 0, choice = 0;
 169         int first_item =  0, max_choice;
 170         WINDOW *dialog, *menu;
 171
 172 do_resize:
 173         height = getmaxy(stdscr);
 174         width = getmaxx(stdscr);
 175         if (height < MENUBOX_HEIGTH_MIN || width < MENUBOX_WIDTH_MIN)
 176                 return -ERRDISPLAYTOOSMALL;
 177
 178         height -= 4;
 179         width  -= 5;
 180         menu_height = height - 10;
 181
 182         max_choice = MIN(menu_height, item_count());
 183
 184         /* center dialog box on screen */
 185         x = (getmaxx(stdscr) - width) / 2;
 186         y = (getmaxy(stdscr) - height) / 2;
 187
 188         draw_shadow(stdscr, y, x, height, width);
 189
 190         dialog = newwin(height, width, y, x);
 191         keypad(dialog, TRUE);
 192
 193         draw_box(dialog, 0, 0, height, width,
 194                  dlg.dialog.atr, dlg.border.atr);
 195         wattrset(dialog, dlg.border.atr);
 196         mvwaddch(dialog, height - 3, 0, ACS_LTEE);
 197         for (i = 0; i < width - 2; i++)
 198                 waddch(dialog, ACS_HLINE);
 199         wattrset(dialog, dlg.dialog.atr);
 200         wbkgdset(dialog, dlg.dialog.atr & A_COLOR);
 201         waddch(dialog, ACS_RTEE);
 202
 203         print_title(dialog, title, width);
 204
 205         wattrset(dialog, dlg.dialog.atr);
 206         print_autowrap(dialog, prompt, width - 2, 1, 3);
 207
 208         menu_width = width - 6;
 209         box_y = height - menu_height - 5;
 210         box_x = (width - menu_width) / 2 - 1;
 211
 212         /* create new window for the menu */
 213         menu = subwin(dialog, menu_height, menu_width,
 214                       y + box_y + 1, x + box_x + 1);
 215         keypad(menu, TRUE);
 216
 217         /* draw a box around the menu items */
 218         draw_box(dialog, box_y, box_x, menu_height + 2, menu_width + 2,
 219                  dlg.menubox_border.atr, dlg.menubox.atr);
 220
 221         if (menu_width >= 80)
 222                 item_x = (menu_width - 70) / 2;
 223         else
 224                 item_x = 4;
 225
 226         /* Set choice to default item */
 227         item_foreach()
 228                 if (selected && (selected == item_data()))
 229                         choice = item_n();
 230         /* get the saved scroll info */
 231         scroll = *s_scroll;
 232         if ((scroll <= choice) && (scroll + max_choice > choice) &&
 233            (scroll >= 0) && (scroll + max_choice <= item_count())) {
 234                 first_item = scroll;
 235                 choice = choice - scroll;
 236         } else {
 237                 scroll = 0;
 238         }
 239         if ((choice >= max_choice)) {
 240                 if (choice >= item_count() - max_choice / 2)
 241                         scroll = first_item = item_count() - max_choice;
 242                 else
 243                         scroll = first_item = choice - max_choice / 2;
 244                 choice = choice - scroll;
 245         }
 246
 247         /* Print the menu */
 248         for (i = 0; i < max_choice; i++) {
 249                 print_item(first_item + i, i, i == choice);
 250         }
 251
 252         wnoutrefresh(menu);
 253
 254         print_arrows(dialog, item_count(), scroll,
 255                      box_y, box_x + item_x + 1, menu_height);
 256
 257         print_buttons(dialog, height, width, 0);
 258         wmove(menu, choice, item_x + 1);
 259         wrefresh(menu);
 260
 261         while (key != KEY_ESC) {
 262                 key = wgetch(menu);
 263
 264                 if (key < 256 && isalpha(key))
 265                         key = tolower(key);
 266
 267                 if (strchr("ynmh", key))
 268                         i = max_choice;
 269                 else {
 270                         for (i = choice + 1; i < max_choice; i++) {
 271                                 item_set(scroll + i);
 272                                 j = first_alpha(item_str(), "YyNnMmHh");
 273                                 if (key == tolower(item_str()[j]))
 274                                         break;
 275                         }
 276                         if (i == max_choice)
 277                                 for (i = 0; i < max_choice; i++) {
 278                                         item_set(scroll + i);
 279                                         j = first_alpha(item_str(), "YyNnMmHh");
 280                                         if (key == tolower(item_str()[j]))
 281                                                 break;
 282                                 }
 283                 }
 284
 285                 if (item_count() != 0 &&
 286                     (i < max_choice ||
 287                      key == KEY_UP || key == KEY_DOWN ||
 288                      key == '-' || key == '+' ||
 289                      key == KEY_PPAGE || key == KEY_NPAGE)) {
 290                         /* Remove highligt of current item */
 291                         print_item(scroll + choice, choice, FALSE);
 292
 293                         if (key == KEY_UP || key == '-') {
 294                                 if (choice < 2 && scroll) {
 295                                         /* Scroll menu down */
 296                                         do_scroll(menu, &scroll, -1);
 297
 298                                         print_item(scroll, 0, FALSE);
 299                                 } else
 300                                         choice = MAX(choice - 1, 0);
 301
 302                         } else if (key == KEY_DOWN || key == '+') {
 303                                 print_item(scroll+choice, choice, FALSE);
 304
 305                                 if ((choice > max_choice - 3) &&
 306                                     (scroll + max_choice < item_count())) {
 307                                         /* Scroll menu up */
 308                                         do_scroll(menu, &scroll, 1);
 309
 310                                         print_item(scroll+max_choice - 1,
 311                                                    max_choice - 1, FALSE);
 312                                 } else
 313                                         choice = MIN(choice + 1, max_choice - 1);
 314
 315                         } else if (key == KEY_PPAGE) {
 316                                 scrollok(menu, TRUE);
 317                                 for (i = 0; (i < max_choice); i++) {
 318                                         if (scroll > 0) {
 319                                                 do_scroll(menu, &scroll, -1);
 320                                                 print_item(scroll, 0, FALSE);
 321                                         } else {
 322                                                 if (choice > 0)
 323                                                         choice--;
 324                                         }
 325                                 }
 326
 327                         } else if (key == KEY_NPAGE) {
 328                                 for (i = 0; (i < max_choice); i++) {
 329                                         if (scroll + max_choice < item_count()) {
 330                                                 do_scroll(menu, &scroll, 1);
 331                                                 print_item(scroll+max_choice-1,
 332                                                            max_choice - 1, FALSE);
 333                                         } else {
 334                                                 if (choice + 1 < max_choice)
 335                                                         choice++;
 336                                         }
 337                                 }
 338                         } else
 339                                 choice = i;
 340
 341                         print_item(scroll + choice, choice, TRUE);
 342
 343                         print_arrows(dialog, item_count(), scroll,
 344                                      box_y, box_x + item_x + 1, menu_height);
 345
 346                         wnoutrefresh(dialog);
 347                         wrefresh(menu);
 348
 349                         continue;       /* wait for another key press */
 350                 }
 351
 352                 switch (key) {
 353                 case KEY_LEFT:
 354                 case TAB:
 355                 case KEY_RIGHT:
 356                         button = ((key == KEY_LEFT ? --button : ++button) < 0)
 357                             ? 4 : (button > 4 ? 0 : button);
 358
 359                         print_buttons(dialog, height, width, button);
 360                         wrefresh(menu);
 361                         break;
 362                 case ' ':
 363                 case 's':
 364                 case 'y':
 365                 case 'n':
 366                 case 'm':
 367                 case '/':
 368                 case 'h':
 369                 case '?':
 370                 case 'z':
 371                 case '\n':
 372                         /* save scroll info */
 373                         *s_scroll = scroll;
 374                         delwin(menu);
 375                         delwin(dialog);
 376                         item_set(scroll + choice);
 377                         item_set_selected(1);
 378                         switch (key) {
 379                         case 'h':
 380                         case '?':
 381                                 return 2;
 382                         case 's':
 383                         case 'y':
 384                                 return 5;
 385                         case 'n':
 386                                 return 6;
 387                         case 'm':
 388                                 return 7;
 389                         case ' ':
 390                                 return 8;
 391                         case '/':
 392                                 return 9;
 393                         case 'z':
 394                                 return 10;
 395                         case '\n':
 396                                 return button;
 397                         }
 398                         return 0;
 399                 case 'e':
 400                 case 'x':
 401                         key = KEY_ESC;
 402                         break;
 403                 case KEY_ESC:
 404                         key = on_key_esc(menu);
 405                         break;
 406                 case KEY_RESIZE:
 407                         on_key_resize();
 408                         delwin(menu);
 409                         delwin(dialog);
 410                         goto do_resize;
 411                 }
 412         }
 413         delwin(menu);
 414         delwin(dialog);
 415         return key;             /* ESC pressed */
 416 }