+
+// Line-editing functions borrowed from gummiboot (cursor_left(), cursor_right(), & line_edit()).
+// gummiboot is copyright (c) 2012 by Kay Sievers <kay.sievers@vrfy.org> and Harald Hoyer
+// <harald@redhat.com> and is licensed under the LGPL 2.1.
+
+static void cursor_left(UINTN *cursor, UINTN *first)
+{
+ if ((*cursor) > 0)
+ (*cursor)--;
+ else if ((*first) > 0)
+ (*first)--;
+}
+
+static void cursor_right(UINTN *cursor, UINTN *first, UINTN x_max, UINTN len)
+{
+ if ((*cursor)+2 < x_max)
+ (*cursor)++;
+ else if ((*first) + (*cursor) < len)
+ (*first)++;
+}
+
+BOOLEAN line_edit(CHAR16 *line_in, CHAR16 **line_out, UINTN x_max, UINTN y_pos) {
+ CHAR16 *line;
+ UINTN size;
+ UINTN len;
+ UINTN first;
+ CHAR16 *print;
+ UINTN cursor;
+ BOOLEAN exit;
+ BOOLEAN enter;
+
+ if (!line_in)
+ line_in = L"";
+ size = StrLen(line_in) + 1024;
+ line = AllocatePool(size * sizeof(CHAR16));
+ StrCpy(line, line_in);
+ len = StrLen(line);
+ print = AllocatePool(x_max * sizeof(CHAR16));
+
+ refit_call2_wrapper(ST->ConOut->EnableCursor, ST->ConOut, TRUE);
+
+ first = 0;
+ cursor = 0;
+ enter = FALSE;
+ exit = FALSE;
+ while (!exit) {
+ UINTN index;
+ EFI_STATUS err;
+ EFI_INPUT_KEY key;
+ UINTN i;
+
+ i = len - first;
+ if (i >= x_max-2)
+ i = x_max-2;
+ CopyMem(print, line + first, i * sizeof(CHAR16));
+ print[i++] = ' ';
+ print[i] = '\0';
+
+ refit_call3_wrapper(ST->ConOut->SetCursorPosition, ST->ConOut, 0, y_pos);
+ refit_call2_wrapper(ST->ConOut->OutputString, ST->ConOut, print);
+ refit_call3_wrapper(ST->ConOut->SetCursorPosition, ST->ConOut, cursor, y_pos);
+
+ refit_call3_wrapper(BS->WaitForEvent, 1, &ST->ConIn->WaitForKey, &index);
+ err = refit_call2_wrapper(ST->ConIn->ReadKeyStroke, ST->ConIn, &key);
+ if (EFI_ERROR(err))
+ continue;
+
+ switch (key.ScanCode) {
+ case SCAN_ESC:
+ exit = TRUE;
+ break;
+ case SCAN_HOME:
+ cursor = 0;
+ first = 0;
+ continue;
+ case SCAN_END:
+ cursor = len;
+ if (cursor >= x_max) {
+ cursor = x_max-2;
+ first = len - (x_max-2);
+ }
+ continue;
+ case SCAN_UP:
+ while((first + cursor) && line[first + cursor] == ' ')
+ cursor_left(&cursor, &first);
+ while((first + cursor) && line[first + cursor] != ' ')
+ cursor_left(&cursor, &first);
+ while((first + cursor) && line[first + cursor] == ' ')
+ cursor_left(&cursor, &first);
+ if (first + cursor != len && first + cursor)
+ cursor_right(&cursor, &first, x_max, len);
+ refit_call3_wrapper(ST->ConOut->SetCursorPosition, ST->ConOut, cursor, y_pos);
+ continue;
+ case SCAN_DOWN:
+ while(line[first + cursor] && line[first + cursor] == ' ')
+ cursor_right(&cursor, &first, x_max, len);
+ while(line[first + cursor] && line[first + cursor] != ' ')
+ cursor_right(&cursor, &first, x_max, len);
+ while(line[first + cursor] && line[first + cursor] == ' ')
+ cursor_right(&cursor, &first, x_max, len);
+ refit_call3_wrapper(ST->ConOut->SetCursorPosition, ST->ConOut, cursor, y_pos);
+ continue;
+ case SCAN_RIGHT:
+ if (first + cursor == len)
+ continue;
+ cursor_right(&cursor, &first, x_max, len);
+ refit_call3_wrapper(ST->ConOut->SetCursorPosition, ST->ConOut, cursor, y_pos);
+ continue;
+ case SCAN_LEFT:
+ cursor_left(&cursor, &first);
+ refit_call3_wrapper(ST->ConOut->SetCursorPosition, ST->ConOut, cursor, y_pos);
+ continue;
+ case SCAN_DELETE:
+ if (len == 0)
+ continue;
+ if (first + cursor == len)
+ continue;
+ for (i = first + cursor; i < len; i++)
+ line[i] = line[i+1];
+ line[len-1] = ' ';
+ len--;
+ continue;
+ }
+
+ switch (key.UnicodeChar) {
+ case CHAR_LINEFEED:
+ case CHAR_CARRIAGE_RETURN:
+ if (StrCmp(line, line_in) != 0) {
+ *line_out = line;
+ line = NULL;
+ }
+ enter = TRUE;
+ exit = TRUE;
+ break;
+ case CHAR_BACKSPACE:
+ if (len == 0)
+ continue;
+ if (first == 0 && cursor == 0)
+ continue;
+ for (i = first + cursor-1; i < len; i++)
+ line[i] = line[i+1];
+ len--;
+ if (cursor > 0)
+ cursor--;
+ if (cursor > 0 || first == 0)
+ continue;
+ /* show full line if it fits */
+ if (len < x_max-2) {
+ cursor = first;
+ first = 0;
+ continue;
+ }
+ /* jump left to see what we delete */
+ if (first > 10) {
+ first -= 10;
+ cursor = 10;
+ } else {
+ cursor = first;
+ first = 0;
+ }
+ continue;
+ case '\t':
+ case ' ' ... '~':
+ case 0x80 ... 0xffff:
+ if (len+1 == size)
+ continue;
+ for (i = len; i > first + cursor; i--)
+ line[i] = line[i-1];
+ line[first + cursor] = key.UnicodeChar;
+ len++;
+ line[len] = '\0';
+ if (cursor+2 < x_max)
+ cursor++;
+ else if (first + cursor < len)
+ first++;
+ continue;
+ }
+ }
+
+ refit_call2_wrapper(ST->ConOut->EnableCursor, ST->ConOut, FALSE);
+ FreePool(print);
+ FreePool(line);
+ return enter;
+} /* BOOLEAN line_edit() */