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/*
* 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)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include "dialog.h"
static void back_lines (int n);
static void print_page (WINDOW * win, int height, int width);
static void print_line (WINDOW * win, int row, int width);
static char *get_line (void);
static void print_position (WINDOW * win, int height, int width);
static int hscroll = 0, fd, file_size, bytes_read;
static int begin_reached = 1, end_reached = 0, page_length;
static char *buf, *page;
/*
* Display text from a file in a dialog box.
*/
int
dialog_textbox (const char *title, const char *file, int height, int width)
{
int i, x, y, cur_x, cur_y, fpos, key = 0;
int passed_end;
char search_term[MAX_LEN + 1];
WINDOW *dialog, *text;
search_term[0] = '\0'; /* no search term entered yet */
/* Open input file for reading */
if ((fd = open (file, O_RDONLY)) == -1) {
endwin ();
fprintf (stderr,
"\nCan't open input file in dialog_textbox().\n");
exit (-1);
}
/* Get file size. Actually, 'file_size' is the real file size - 1,
since it's only the last byte offset from the beginning */
if ((file_size = lseek (fd, 0, SEEK_END)) == -1) {
endwin ();
fprintf (stderr, "\nError getting file size in dialog_textbox().\n");
exit (-1);
}
/* Restore file pointer to beginning of file after getting file size */
if (lseek (fd, 0, SEEK_SET) == -1) {
endwin ();
fprintf (stderr, "\nError moving file pointer in dialog_textbox().\n");
exit (-1);
}
/* Allocate space for read buffer */
if ((buf = malloc (BUF_SIZE + 1)) == NULL) {
endwin ();
fprintf (stderr, "\nCan't allocate memory in dialog_textbox().\n");
exit (-1);
}
if ((bytes_read = read (fd, buf, BUF_SIZE)) == -1) {
endwin ();
fprintf (stderr, "\nError reading file in dialog_textbox().\n");
exit (-1);
}
buf[bytes_read] = '\0'; /* mark end of valid data */
page = buf; /* page is pointer to start of page to be displayed */
/* center dialog box on screen */
x = (COLS - width) / 2;
y = (LINES - height) / 2;
draw_shadow (stdscr, y, x, height, width);
dialog = newwin (height, width, y, x);
keypad (dialog, TRUE);
/* Create window for text region, used for scrolling text */
text = subwin (dialog, height - 4, width - 2, y + 1, x + 1);
wattrset (text, dialog_attr);
wbkgdset (text, dialog_attr & A_COLOR);
keypad (text, TRUE);
/* register the new window, along with its borders */
draw_box (dialog, 0, 0, height, width, dialog_attr, border_attr);
wattrset (dialog, border_attr);
mvwaddch (dialog, height-3, 0, ACS_LTEE);
for (i = 0; i < width - 2; i++)
waddch (dialog, ACS_HLINE);
wattrset (dialog, dialog_attr);
wbkgdset (dialog, dialog_attr & A_COLOR);
waddch (dialog, ACS_RTEE);
if (title != NULL && strlen(title) >= width-2 ) {
/* truncate long title -- mec */
char * title2 = malloc(width-2+1);
memcpy( title2, title, width-2 );
title2[width-2] = '\0';
title = title2;
}
if (title != NULL) {
wattrset (dialog, title_attr);
mvwaddch (dialog, 0, (width - strlen(title))/2 - 1, ' ');
waddstr (dialog, (char *)title);
waddch (dialog, ' ');
}
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 (text, height - 4, width - 2, dialog_attr);
print_page (text, height - 4, width - 2);
print_position (dialog, height, width);
wmove (dialog, cur_y, cur_x); /* Restore cursor position */
wrefresh (dialog);
while ((key != ESC) && (key != '\n')) {
key = wgetch (dialog);
switch (key) {
case 'E': /* Exit */
case 'e':
case 'X':
case 'x':
delwin (dialog);
free (buf);
close (fd);
return 0;
case 'g': /* First page */
case KEY_HOME:
if (!begin_reached) {
begin_reached = 1;
/* First page not in buffer? */
if ((fpos = lseek (fd, 0, SEEK_CUR)) == -1) {
endwin ();
fprintf (stderr,
"\nError moving file pointer in dialog_textbox().\n");
exit (-1);
}
if (fpos > bytes_read) { /* Yes, we have to read it in */
if (lseek (fd, 0, SEEK_SET) == -1) {
endwin ();
fprintf (stderr, "\nError moving file pointer in "
"dialog_textbox().\n");
exit (-1);
}
if ((bytes_read = read (fd, buf, BUF_SIZE)) == -1) {
endwin ();
fprintf (stderr,
"\nError reading file in dialog_textbox().\n");
exit (-1);
}
buf[bytes_read] = '\0';
}
page = buf;
print_page (text, height - 4, width - 2);
print_position (dialog, height, width);
wmove (dialog, cur_y, cur_x); /* Restore cursor position */
wrefresh (dialog);
}
break;
case 'G': /* Last page */
case KEY_END:
end_reached = 1;
/* Last page not in buffer? */
if ((fpos = lseek (fd, 0, SEEK_CUR)) == -1) {
endwin ();
fprintf (stderr,
"\nError moving file pointer in dialog_textbox().\n");
exit (-1);
}
if (fpos < file_size) { /* Yes, we have to read it in */
if (lseek (fd, -BUF_SIZE, SEEK_END) == -1) {
endwin ();
fprintf (stderr,
"\nError moving file pointer in dialog_textbox().\n");
exit (-1);
}
if ((bytes_read = read (fd, buf, BUF_SIZE)) == -1) {
endwin ();
fprintf (stderr,
"\nError reading file in dialog_textbox().\n");
exit (-1);
}
buf[bytes_read] = '\0';
}
page = buf + bytes_read;
back_lines (height - 4);
print_page (text, height - 4, width - 2);
print_position (dialog, height, width);
wmove (dialog, cur_y, cur_x); /* Restore cursor position */
wrefresh (dialog);
break;
case 'K': /* Previous line */
case 'k':
case KEY_UP:
if (!begin_reached) {
back_lines (page_length + 1);
/* We don't call print_page() here but use scrolling to ensure
faster screen update. However, 'end_reached' and
'page_length' should still be updated, and 'page' should
point to start of next page. This is done by calling
get_line() in the following 'for' loop. */
scrollok (text, TRUE);
wscrl (text, -1); /* Scroll text region down one line */
scrollok (text, FALSE);
page_length = 0;
passed_end = 0;
for (i = 0; i < height - 4; i++) {
if (!i) {
/* print first line of page */
print_line (text, 0, width - 2);
wnoutrefresh (text);
} else
/* Called to update 'end_reached' and 'page' */
get_line ();
if (!passed_end)
page_length++;
if (end_reached && !passed_end)
passed_end = 1;
}
print_position (dialog, height, width);
wmove (dialog, cur_y, cur_x); /* Restore cursor position */
wrefresh (dialog);
}
break;
case 'B': /* Previous page */
case 'b':
case KEY_PPAGE:
if (begin_reached)
break;
back_lines (page_length + height - 4);
print_page (text, height - 4, width - 2);
print_position (dialog, height, width);
wmove (dialog, cur_y, cur_x);
wrefresh (dialog);
break;
case 'J': /* Next line */
case 'j':
case KEY_DOWN:
if (!end_reached) {
begin_reached = 0;
scrollok (text, TRUE);
scroll (text); /* Scroll text region up one line */
scrollok (text, FALSE);
print_line (text, height - 5, width - 2);
wnoutrefresh (text);
print_position (dialog, height, width);
wmove (dialog, cur_y, cur_x); /* Restore cursor position */
wrefresh (dialog);
}
break;
case KEY_NPAGE: /* Next page */
case ' ':
if (end_reached)
break;
begin_reached = 0;
print_page (text, height - 4, width - 2);
print_position (dialog, height, width);
wmove (dialog, cur_y, cur_x);
wrefresh (dialog);
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);
print_page (text, height - 4, width - 2);
wmove (dialog, cur_y, cur_x);
wrefresh (dialog);
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);
print_page (text, height - 4, width - 2);
wmove (dialog, cur_y, cur_x);
wrefresh (dialog);
break;
case ESC:
break;
}
}
delwin (dialog);
free (buf);
close (fd);
return -1; /* ESC pressed */
}
/*
* Go back 'n' lines in text file. Called by dialog_textbox().
* 'page' will be updated to point to the desired line in 'buf'.
*/
static void
back_lines (int n)
{
int i, fpos;
begin_reached = 0;
/* We have to distinguish between end_reached and !end_reached
since at end of file, the line is not ended by a '\n'.
The code inside 'if' basically does a '--page' to move one
character backward so as to skip '\n' of the previous line */
if (!end_reached) {
/* Either beginning of buffer or beginning of file reached? */
if (page == buf) {
if ((fpos = lseek (fd, 0, SEEK_CUR)) == -1) {
endwin ();
fprintf (stderr, "\nError moving file pointer in "
"back_lines().\n");
exit (-1);
}
if (fpos > bytes_read) { /* Not beginning of file yet */
/* We've reached beginning of buffer, but not beginning of
file yet, so read previous part of file into buffer.
Note that we only move backward for BUF_SIZE/2 bytes,
but not BUF_SIZE bytes to avoid re-reading again in
print_page() later */
/* Really possible to move backward BUF_SIZE/2 bytes? */
if (fpos < BUF_SIZE / 2 + bytes_read) {
/* No, move less then */
if (lseek (fd, 0, SEEK_SET) == -1) {
endwin ();
fprintf (stderr, "\nError moving file pointer in "
"back_lines().\n");
exit (-1);
}
page = buf + fpos - bytes_read;
} else { /* Move backward BUF_SIZE/2 bytes */
if (lseek (fd, -(BUF_SIZE / 2 + bytes_read), SEEK_CUR)
== -1) {
endwin ();
fprintf (stderr, "\nError moving file pointer "
"in back_lines().\n");
exit (-1);
}
page = buf + BUF_SIZE / 2;
}
if ((bytes_read = read (fd, buf, BUF_SIZE)) == -1) {
endwin ();
fprintf (stderr, "\nError reading file in back_lines().\n");
exit (-1);
}
buf[bytes_read] = '\0';
} else { /* Beginning of file reached */
begin_reached = 1;
return;
}
}
if (*(--page) != '\n') { /* '--page' here */
/* Something's wrong... */
endwin ();
fprintf (stderr, "\nInternal error in back_lines().\n");
exit (-1);
}
}
/* Go back 'n' lines */
for (i = 0; i < n; i++)
do {
if (page == buf) {
if ((fpos = lseek (fd, 0, SEEK_CUR)) == -1) {
endwin ();
fprintf (stderr,
"\nError moving file pointer in back_lines().\n");
exit (-1);
}
if (fpos > bytes_read) {
/* Really possible to move backward BUF_SIZE/2 bytes? */
if (fpos < BUF_SIZE / 2 + bytes_read) {
/* No, move less then */
if (lseek (fd, 0, SEEK_SET) == -1) {
endwin ();
fprintf (stderr, "\nError moving file pointer "
"in back_lines().\n");
exit (-1);
}
page = buf + fpos - bytes_read;
} else { /* Move backward BUF_SIZE/2 bytes */
if (lseek (fd, -(BUF_SIZE / 2 + bytes_read),
SEEK_CUR) == -1) {
endwin ();
fprintf (stderr, "\nError moving file pointer"
" in back_lines().\n");
exit (-1);
}
page = buf + BUF_SIZE / 2;
}
if ((bytes_read = read (fd, buf, BUF_SIZE)) == -1) {
endwin ();
fprintf (stderr, "\nError reading file in "
"back_lines().\n");
exit (-1);
}
buf[bytes_read] = '\0';
} else { /* Beginning of file reached */
begin_reached = 1;
return;
}
}
} while (*(--page) != '\n');
page++;
}
/*
* Print a new page of text. Called by dialog_textbox().
*/
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 a new line of text. Called by dialog_textbox() and print_page().
*/
static void
print_line (WINDOW * win, int row, int width)
{
int y, x;
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));
getyx (win, y, x);
/* Clear 'residue' of previous line */
#if OLD_NCURSES
{
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, fpos;
static char line[MAX_LEN + 1];
end_reached = 0;
while (*page != '\n') {
if (*page == '\0') {
/* Either end of file or end of buffer reached */
if ((fpos = lseek (fd, 0, SEEK_CUR)) == -1) {
endwin ();
fprintf (stderr, "\nError moving file pointer in "
"get_line().\n");
exit (-1);
}
if (fpos < file_size) { /* Not end of file yet */
/* We've reached end of buffer, but not end of file yet,
so read next part of file into buffer */
if ((bytes_read = read (fd, buf, BUF_SIZE)) == -1) {
endwin ();
fprintf (stderr, "\nError reading file in get_line().\n");
exit (-1);
}
buf[bytes_read] = '\0';
page = buf;
} else {
if (!end_reached)
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 pass '\n' */
return line;
}
/*
* Print current position
*/
static void
print_position (WINDOW * win, int height, int width)
{
int fpos, percent;
if ((fpos = lseek (fd, 0, SEEK_CUR)) == -1) {
endwin ();
fprintf (stderr, "\nError moving file pointer in print_position().\n");
exit (-1);
}
wattrset (win, position_indicator_attr);
wbkgdset (win, position_indicator_attr & A_COLOR);
percent = !file_size ?
100 : ((fpos - bytes_read + page - buf) * 100) / file_size;
wmove (win, height - 3, width - 9);
wprintw (win, "(%3d%%)", percent);
}
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