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/*
* textbox.c -- implements the text box
*
* AUTHOR: Savio Lam (lam836@cs.cuhk.hk)
*
* 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 int get_search_term(WINDOW *win, char *search_term, int height, int width);
static void print_position(WINDOW *win, int height, int width);
static int hscroll = 0, fd, file_size, bytes_read, begin_reached = 1,
end_reached = 0, page_length;
static char *buf, *page;
/*
* Display text from a file in a dialog box.
*/
int dialog_textbox(char *title, char *file, int height, int width)
{
int i, x, y, cur_x, cur_y, fpos, key = 0, dir, temp, temp1;
#ifdef HAVE_NCURSES
int passed_end;
#endif
char search_term[MAX_LEN+1], *tempptr, *found;
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;
#ifdef HAVE_NCURSES
if (use_shadow)
draw_shadow(stdscr, y, x, height, width);
#endif
dialog = newwin(height, width, y, x);
keypad(dialog, TRUE);
/* Create window for text region, used for scrolling text */
/* text = newwin(height-4, width-2, y+1, x+1); */
text = subwin(dialog, height-4, width-2, y+1, x+1);
keypad(text, TRUE);
draw_box(dialog, 0, 0, height, width, dialog_attr, border_attr);
wattrset(dialog, border_attr);
wmove(dialog, height-3, 0);
waddch(dialog, ACS_LTEE);
for (i = 0; i < width-2; i++)
waddch(dialog, ACS_HLINE);
wattrset(dialog, dialog_attr);
waddch(dialog, ACS_RTEE);
wmove(dialog, height-2, 1);
for (i = 0; i < width-2; i++)
waddch(dialog, ' ');
if (title != NULL) {
wattrset(dialog, title_attr);
wmove(dialog, 0, (width - strlen(title))/2 - 1);
waddch(dialog, ' ');
waddstr(dialog, 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':
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 */
#ifdef HAVE_NCURSES
case KEY_END:
#endif
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);
#ifdef HAVE_NCURSES
/* 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_line(text, 0, width-2); /* print first line of page */
wnoutrefresh(text);
}
else
get_line(); /* Called to update 'end_reached' and 'page' */
if (!passed_end)
page_length++;
if (end_reached && !passed_end)
passed_end = 1;
}
#else
print_page(text, height-4, width-2);
#endif
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) {
back_lines(page_length + 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 '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);
#ifndef HAVE_NCURSES
wmove(text, height-5, 0);
waddch(text, ' ');
wmove(text, height-5, width-3);
waddch(text, ' ');
#endif
wnoutrefresh(text);
print_position(dialog, height, width);
wmove(dialog, cur_y, cur_x); /* Restore cursor position */
wrefresh(dialog);
}
break;
case ' ': /* Next page */
case KEY_NPAGE:
if (!end_reached) {
begin_reached = 0;
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 '0': /* Beginning of line */
case 'H': /* Scroll left */
case 'h':
case KEY_LEFT:
if (hscroll > 0) {
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); /* Restore cursor position */
wrefresh(dialog);
}
break;
case 'L': /* Scroll right */
case 'l':
case KEY_RIGHT:
if (hscroll < MAX_LEN) {
hscroll++;
/* Reprint current page to scroll horizontally */
back_lines(page_length);
print_page(text, height-4, width-2);
wmove(dialog, cur_y, cur_x); /* Restore cursor position */
wrefresh(dialog);
}
break;
case '/': /* Forward search */
case 'n': /* Repeat forward search */
case '?': /* Backward search */
case 'N': /* Repeat backward search */
/* set search direction */
dir = (key == '/' || key == 'n') ? 1 : 0;
if (dir ? !end_reached : !begin_reached) {
if (key == 'n' || key == 'N') {
if (search_term[0] == '\0') { /* No search term yet */
fprintf(stderr, "\a"); /* beep */
break;
}
}
else /* Get search term from user */
if (get_search_term(text, search_term, height-4, width-2) == -1) {
/* ESC pressed in get_search_term(). Reprint page to clear box */
wattrset(text, dialog_attr);
back_lines(page_length);
print_page(text, height-4, width-2);
wmove(dialog, cur_y, cur_x); /* Restore cursor position */
wrefresh(dialog);
break;
}
/* Save variables for restoring in case search term can't be found */
tempptr = page;
temp = begin_reached;
temp1 = end_reached;
if ((fpos = lseek(fd, 0, SEEK_CUR)) == -1) {
endwin();
fprintf(stderr, "\nError moving file pointer in dialog_textbox().\n");
exit(-1);
}
fpos -= bytes_read;
/* update 'page' to point to next (previous) line before
forward (backward) searching */
back_lines(dir ? page_length-1 : page_length+1);
found = NULL;
if (dir) /* Forward search */
while((found = strstr(get_line(), search_term)) == NULL) {
if (end_reached)
break;
}
else /* Backward search */
while((found = strstr(get_line(), search_term)) == NULL) {
if (begin_reached)
break;
back_lines(2);
}
if (found == NULL) { /* not found */
fprintf(stderr, "\a"); /* beep */
/* Restore program state to that before searching */
if (lseek(fd, fpos, 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 = tempptr;
begin_reached = temp;
end_reached = temp1;
/* move 'page' to point to start of current page in order to
re-print current page. Note that 'page' always points to
start of next page, so this is necessary */
back_lines(page_length);
}
else /* Search term found */
back_lines(1);
/* Reprint page */
wattrset(text, dialog_attr);
print_page(text, height-4, width-2);
if (found != NULL)
print_position(dialog, height, width);
wmove(dialog, cur_y, cur_x); /* Restore cursor position */
wrefresh(dialog);
}
else /* no need to find */
fprintf(stderr, "\a"); /* beep */
break;
case ESC:
break;
}
}
delwin(dialog);
free(buf);
close(fd);
return -1; /* ESC pressed */
}
/* End of dialog_textbox() */
/*
* 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++;
}
/* End of back_lines() */
/*
* 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);
}
/* End of print_page() */
/*
* Print a new line of text. Called by dialog_textbox() and print_page().
*/
static void print_line(WINDOW *win, int row, int width)
{
int i, 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,' ');
#ifdef HAVE_NCURSES
waddnstr(win, line, MIN(strlen(line),width-2));
#else
line[MIN(strlen(line),width-2)] = '\0';
waddstr(win, line);
#endif
getyx(win, y, x);
/* Clear 'residue' of previous line */
for (i = 0; i < width-x; i++)
waddch(win, ' ');
}
/* End of print_line() */
/*
* 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 {
if (i == MAX_LEN) /* Truncate lines longer than MAX_LEN characters */
line[i++] = '\0';
page++;
}
}
if (i <= MAX_LEN)
line[i] = '\0';
if (!end_reached)
page++; /* move pass '\n' */
return line;
}
/* End of get_line() */
/*
* Display a dialog box and get the search term from user
*/
static int get_search_term(WINDOW *win, char *search_term, int height, int width)
{
int i, x, y, input_x = 0, scroll = 0, key = 0,
box_height = 3, box_width = 30;
x = (width - box_width)/2;
y = (height - box_height)/2;
#ifdef HAVE_NCURSES
if (use_shadow)
draw_shadow(win, y, x, box_height, box_width);
#endif
draw_box(win, y, x, box_height, box_width, dialog_attr, searchbox_border_attr);
wattrset(win, searchbox_title_attr);
wmove(win, y, x+box_width/2-4);
waddstr(win, " Search ");
box_width -= 2;
wmove(win, y+1, x+1);
wrefresh(win);
search_term[0] = '\0';
wattrset(win, searchbox_attr);
while (key != ESC) {
key = wgetch(win);
switch (key) {
case '\n':
if (search_term[0] != '\0')
return 0;
break;
case KEY_BACKSPACE:
if (input_x || scroll) {
if (!input_x) {
scroll = scroll < box_width-1 ? 0 : scroll-(box_width-1);
wmove(win, y+1, x+1);
for (i = 0; i < box_width; i++)
waddch(win, search_term[scroll+input_x+i] ?
search_term[scroll+input_x+i] : ' ');
input_x = strlen(search_term) - scroll;
}
else
input_x--;
search_term[scroll+input_x] = '\0';
wmove(win, y+1, input_x + x+1);
waddch(win, ' ');
wmove(win, y+1, input_x + x+1);
wrefresh(win);
}
break;
case ESC:
break;
default:
if (isprint(key))
if (scroll+input_x < MAX_LEN) {
search_term[scroll+input_x] = key;
search_term[scroll+input_x+1] = '\0';
if (input_x == box_width-1) {
scroll++;
wmove(win, y+1, x+1);
for (i = 0; i < box_width-1; i++)
waddch(win, search_term[scroll+i]);
}
else {
wmove(win, y+1, input_x++ + x+1);
waddch(win, key);
}
wrefresh(win);
}
}
}
return -1; /* ESC pressed */
}
/* End of get_search_term() */
/*
* 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);
percent = !file_size ? 100 : ((fpos-bytes_read+page-buf)*100)/file_size;
wmove(win, height-3, width-9);
wprintw(win, "(%3d%%)", percent);
}
/* End of print_position() */
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