// SPDX-License-Identifier: GPL-2.0+
/*
* textbox.c -- implements the text box
*
* ORIGINAL AUTHOR: Savio Lam ([email protected])
* MODIFIED FOR LINUX KERNEL CONFIG BY: William Roadcap ([email protected])
*/
#include "dialog.h"
static int hscroll;
static int begin_reached, end_reached, page_length;
static const char *buf, *page;
static size_t start, end;
/*
* 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++;
}
}
/*
* 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 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 */
wclrtoeol(win);
}
/*
* Print a new page of text.
*/
static void print_page(WINDOW *win, int height, int width)
{
int i, passed_end = 0;
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 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);
}
/*
* refresh window content
*/
static void refresh_text_box(WINDOW *dialog, WINDOW *box, int boxh, int boxw,
int cur_y, int cur_x)
{
start = page - buf;
print_page(box, boxh, boxw);
print_position(dialog);
wmove(dialog, cur_y, cur_x); /* Restore cursor position */
wrefresh(dialog);
end = page - buf;
}
/*
* Display text from a file in a dialog box.
*
* keys is a null-terminated array
*/
int dialog_textbox(const char *title, const char *tbuf, int initial_height,
int initial_width, int *_vscroll, int *_hscroll,
int (*extra_key_cb)(int, size_t, size_t, void *), 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_HEIGHT_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);
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);
}
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);
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);
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);
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);
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);
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);
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);
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:
if (extra_key_cb && extra_key_cb(key, start, end, data)) {
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;
}
Codebase Browser
linux