| // SPDX-License-Identifier: GPL-2.0+ |
| /* |
| * textbox.c -- implements the text box |
| * |
| * ORIGINAL AUTHOR: Savio Lam (lam836@cs.cuhk.hk) |
| * MODIFIED FOR LINUX KERNEL CONFIG BY: William Roadcap (roadcap@cfw.com) |
| */ |
| |
| #include "dialog.h" |
| |
| static void back_lines(int n); |
| static void print_page(WINDOW *win, int height, int width, update_text_fn |
| update_text, void *data); |
| static void print_line(WINDOW *win, int row, int width); |
| static char *get_line(void); |
| static void print_position(WINDOW * win); |
| |
| static int hscroll; |
| static int begin_reached, end_reached, page_length; |
| static char *buf; |
| static char *page; |
| |
| /* |
| * refresh window content |
| */ |
| static void refresh_text_box(WINDOW *dialog, WINDOW *box, int boxh, int boxw, |
| int cur_y, int cur_x, update_text_fn update_text, |
| void *data) |
| { |
| print_page(box, boxh, boxw, update_text, data); |
| print_position(dialog); |
| wmove(dialog, cur_y, cur_x); /* Restore cursor position */ |
| wrefresh(dialog); |
| } |
| |
| |
| /* |
| * Display text from a file in a dialog box. |
| * |
| * keys is a null-terminated array |
| * update_text() may not add or remove any '\n' or '\0' in tbuf |
| */ |
| int dialog_textbox(const char *title, char *tbuf, int initial_height, |
| int initial_width, int *keys, int *_vscroll, int *_hscroll, |
| update_text_fn update_text, void *data) |
| { |
| int i, x, y, cur_x, cur_y, key = 0; |
| int height, width, boxh, boxw; |
| WINDOW *dialog, *box; |
| bool done = false; |
| |
| begin_reached = 1; |
| end_reached = 0; |
| page_length = 0; |
| hscroll = 0; |
| buf = tbuf; |
| page = buf; /* page is pointer to start of page to be displayed */ |
| |
| if (_vscroll && *_vscroll) { |
| begin_reached = 0; |
| |
| for (i = 0; i < *_vscroll; i++) |
| get_line(); |
| } |
| if (_hscroll) |
| hscroll = *_hscroll; |
| |
| do_resize: |
| getmaxyx(stdscr, height, width); |
| if (height < TEXTBOX_HEIGTH_MIN || width < TEXTBOX_WIDTH_MIN) |
| return -ERRDISPLAYTOOSMALL; |
| if (initial_height != 0) |
| height = initial_height; |
| else |
| if (height > 4) |
| height -= 4; |
| else |
| height = 0; |
| if (initial_width != 0) |
| width = initial_width; |
| else |
| if (width > 5) |
| width -= 5; |
| else |
| width = 0; |
| |
| /* center dialog box on screen */ |
| x = (getmaxx(stdscr) - width) / 2; |
| y = (getmaxy(stdscr) - height) / 2; |
| |
| draw_shadow(stdscr, y, x, height, width); |
| |
| dialog = newwin(height, width, y, x); |
| keypad(dialog, TRUE); |
| |
| /* Create window for box region, used for scrolling text */ |
| boxh = height - 4; |
| boxw = width - 2; |
| box = subwin(dialog, boxh, boxw, y + 1, x + 1); |
| wattrset(box, dlg.dialog.atr); |
| wbkgdset(box, dlg.dialog.atr & A_COLOR); |
| |
| keypad(box, TRUE); |
| |
| /* register the new window, along with its borders */ |
| draw_box(dialog, 0, 0, height, width, |
| dlg.dialog.atr, dlg.border.atr); |
| |
| wattrset(dialog, dlg.border.atr); |
| mvwaddch(dialog, height - 3, 0, ACS_LTEE); |
| for (i = 0; i < width - 2; i++) |
| waddch(dialog, ACS_HLINE); |
| wattrset(dialog, dlg.dialog.atr); |
| wbkgdset(dialog, dlg.dialog.atr & A_COLOR); |
| waddch(dialog, ACS_RTEE); |
| |
| print_title(dialog, title, width); |
| |
| print_button(dialog, " Exit ", height - 2, width / 2 - 4, TRUE); |
| wnoutrefresh(dialog); |
| getyx(dialog, cur_y, cur_x); /* Save cursor position */ |
| |
| /* Print first page of text */ |
| attr_clear(box, boxh, boxw, dlg.dialog.atr); |
| refresh_text_box(dialog, box, boxh, boxw, cur_y, cur_x, update_text, |
| data); |
| |
| while (!done) { |
| key = wgetch(dialog); |
| switch (key) { |
| case 'E': /* Exit */ |
| case 'e': |
| case 'X': |
| case 'x': |
| case 'q': |
| case '\n': |
| done = true; |
| break; |
| case 'g': /* First page */ |
| case KEY_HOME: |
| if (!begin_reached) { |
| begin_reached = 1; |
| page = buf; |
| refresh_text_box(dialog, box, boxh, boxw, |
| cur_y, cur_x, update_text, |
| data); |
| } |
| break; |
| case 'G': /* Last page */ |
| case KEY_END: |
| |
| end_reached = 1; |
| /* point to last char in buf */ |
| page = buf + strlen(buf); |
| back_lines(boxh); |
| refresh_text_box(dialog, box, boxh, boxw, cur_y, |
| cur_x, update_text, data); |
| break; |
| case 'K': /* Previous line */ |
| case 'k': |
| case KEY_UP: |
| if (begin_reached) |
| break; |
| |
| back_lines(page_length + 1); |
| refresh_text_box(dialog, box, boxh, boxw, cur_y, |
| cur_x, update_text, data); |
| break; |
| case 'B': /* Previous page */ |
| case 'b': |
| case 'u': |
| case KEY_PPAGE: |
| if (begin_reached) |
| break; |
| back_lines(page_length + boxh); |
| refresh_text_box(dialog, box, boxh, boxw, cur_y, |
| cur_x, update_text, data); |
| break; |
| case 'J': /* Next line */ |
| case 'j': |
| case KEY_DOWN: |
| if (end_reached) |
| break; |
| |
| back_lines(page_length - 1); |
| refresh_text_box(dialog, box, boxh, boxw, cur_y, |
| cur_x, update_text, data); |
| break; |
| case KEY_NPAGE: /* Next page */ |
| case ' ': |
| case 'd': |
| if (end_reached) |
| break; |
| |
| begin_reached = 0; |
| refresh_text_box(dialog, box, boxh, boxw, cur_y, |
| cur_x, update_text, data); |
| break; |
| case '0': /* Beginning of line */ |
| case 'H': /* Scroll left */ |
| case 'h': |
| case KEY_LEFT: |
| if (hscroll <= 0) |
| break; |
| |
| if (key == '0') |
| hscroll = 0; |
| else |
| hscroll--; |
| /* Reprint current page to scroll horizontally */ |
| back_lines(page_length); |
| refresh_text_box(dialog, box, boxh, boxw, cur_y, |
| cur_x, update_text, data); |
| break; |
| case 'L': /* Scroll right */ |
| case 'l': |
| case KEY_RIGHT: |
| if (hscroll >= MAX_LEN) |
| break; |
| hscroll++; |
| /* Reprint current page to scroll horizontally */ |
| back_lines(page_length); |
| refresh_text_box(dialog, box, boxh, boxw, cur_y, |
| cur_x, update_text, data); |
| break; |
| case KEY_ESC: |
| if (on_key_esc(dialog) == KEY_ESC) |
| done = true; |
| break; |
| case KEY_RESIZE: |
| back_lines(height); |
| delwin(box); |
| delwin(dialog); |
| on_key_resize(); |
| goto do_resize; |
| default: |
| for (i = 0; keys[i]; i++) { |
| if (key == keys[i]) { |
| done = true; |
| break; |
| } |
| } |
| } |
| } |
| delwin(box); |
| delwin(dialog); |
| if (_vscroll) { |
| const char *s; |
| |
| s = buf; |
| *_vscroll = 0; |
| back_lines(page_length); |
| while (s < page && (s = strchr(s, '\n'))) { |
| (*_vscroll)++; |
| s++; |
| } |
| } |
| if (_hscroll) |
| *_hscroll = hscroll; |
| return key; |
| } |
| |
| /* |
| * Go back 'n' lines in text. Called by dialog_textbox(). |
| * 'page' will be updated to point to the desired line in 'buf'. |
| */ |
| static void back_lines(int n) |
| { |
| int i; |
| |
| begin_reached = 0; |
| /* Go back 'n' lines */ |
| for (i = 0; i < n; i++) { |
| if (*page == '\0') { |
| if (end_reached) { |
| end_reached = 0; |
| continue; |
| } |
| } |
| if (page == buf) { |
| begin_reached = 1; |
| return; |
| } |
| page--; |
| do { |
| if (page == buf) { |
| begin_reached = 1; |
| return; |
| } |
| page--; |
| } while (*page != '\n'); |
| page++; |
| } |
| } |
| |
| /* |
| * Print a new page of text. |
| */ |
| static void print_page(WINDOW *win, int height, int width, update_text_fn |
| update_text, void *data) |
| { |
| int i, passed_end = 0; |
| |
| if (update_text) { |
| char *end; |
| |
| for (i = 0; i < height; i++) |
| get_line(); |
| end = page; |
| back_lines(height); |
| update_text(buf, page - buf, end - buf, data); |
| } |
| |
| page_length = 0; |
| for (i = 0; i < height; i++) { |
| print_line(win, i, width); |
| if (!passed_end) |
| page_length++; |
| if (end_reached && !passed_end) |
| passed_end = 1; |
| } |
| wnoutrefresh(win); |
| } |
| |
| /* |
| * Print a new line of text. |
| */ |
| static void print_line(WINDOW * win, int row, int width) |
| { |
| char *line; |
| |
| line = get_line(); |
| line += MIN(strlen(line), hscroll); /* Scroll horizontally */ |
| wmove(win, row, 0); /* move cursor to correct line */ |
| waddch(win, ' '); |
| waddnstr(win, line, MIN(strlen(line), width - 2)); |
| |
| /* Clear 'residue' of previous line */ |
| #if OLD_NCURSES |
| { |
| int x = getcurx(win); |
| int i; |
| for (i = 0; i < width - x; i++) |
| waddch(win, ' '); |
| } |
| #else |
| wclrtoeol(win); |
| #endif |
| } |
| |
| /* |
| * Return current line of text. Called by dialog_textbox() and print_line(). |
| * 'page' should point to start of current line before calling, and will be |
| * updated to point to start of next line. |
| */ |
| static char *get_line(void) |
| { |
| int i = 0; |
| static char line[MAX_LEN + 1]; |
| |
| end_reached = 0; |
| while (*page != '\n') { |
| if (*page == '\0') { |
| end_reached = 1; |
| break; |
| } else if (i < MAX_LEN) |
| line[i++] = *(page++); |
| else { |
| /* Truncate lines longer than MAX_LEN characters */ |
| if (i == MAX_LEN) |
| line[i++] = '\0'; |
| page++; |
| } |
| } |
| if (i <= MAX_LEN) |
| line[i] = '\0'; |
| if (!end_reached) |
| page++; /* move past '\n' */ |
| |
| return line; |
| } |
| |
| /* |
| * Print current position |
| */ |
| static void print_position(WINDOW * win) |
| { |
| int percent; |
| |
| wattrset(win, dlg.position_indicator.atr); |
| wbkgdset(win, dlg.position_indicator.atr & A_COLOR); |
| percent = (page - buf) * 100 / strlen(buf); |
| wmove(win, getmaxy(win) - 3, getmaxx(win) - 9); |
| wprintw(win, "(%3d%%)", percent); |
| } |