static int do_output_char(unsigned char c, struct tty_struct *tty, int space)
{
int spaces;
if (!space)
return -1;
switch (c) {
case '\n':
if (O_ONLRET(tty))
tty->column = 0;
if (O_ONLCR(tty)) {
if (space < 2)
return -1;
tty->canon_column = tty->column = 0;
tty->ops->write(tty, "\r\n", 2);
return 2;
}
tty->canon_column = tty->column;
break;
case '\r':
if (O_ONOCR(tty) && tty->column == 0)
return 0;
if (O_OCRNL(tty)) {
c = '\n';
if (O_ONLRET(tty))
tty->canon_column = tty->column = 0;
break;
}
tty->canon_column = tty->column = 0;
break;
case '\t':
spaces = 8 - (tty->column & 7);
if (O_TABDLY(tty) == XTABS) {
if (space < spaces)
return -1;
tty->column += spaces;
tty->ops->write(tty, " ", spaces);
return spaces;
}
tty->column += spaces;
break;
case '\b':
if (tty->column > 0)
tty->column--;
break;
default:
if (!iscntrl(c)) {
if (O_OLCUC(tty))
c = toupper(c);
if (!is_continuation(c, tty))
tty->column++;
}
break;
}
tty_put_char(tty, c);
return 1;
}
/*
* Perform OPOST processing. Returns -1 when the output device is
* full and the character must be retried.
*/
static int opost(unsigned char c, struct tty_struct *tty)
{
int space, spaces;
space = tty->driver.write_room(tty);
if (!space)
return -1;
if (O_OPOST(tty)) {
switch (c) {
case '\n':
if (O_ONLRET(tty))
tty->column = 0;
if (O_ONLCR(tty)) {
if (space < 2)
return -1;
tty->driver.put_char(tty, '\r');
tty->column = 0;
}
tty->canon_column = tty->column;
break;
case '\r':
if (O_ONOCR(tty) && tty->column == 0)
return 0;
if (O_OCRNL(tty)) {
c = '\n';
if (O_ONLRET(tty))
tty->canon_column = tty->column = 0;
break;
}
tty->canon_column = tty->column = 0;
break;
case '\t':
spaces = 8 - (tty->column & 7);
if (O_TABDLY(tty) == XTABS) {
if (space < spaces)
return -1;
tty->column += spaces;
tty->driver.write(tty, 0, " ", spaces);
return 0;
}
tty->column += spaces;
break;
case '\b':
if (tty->column > 0)
tty->column--;
break;
default:
if (O_OLCUC(tty))
c = toupper(c);
if (!iscntrl(c))
tty->column++;
break;
}
}
tty->driver.put_char(tty, c);
return 0;
}
static int opost(unsigned char c, struct tty_struct *tty)
{
if (FULL(&tty->write_q))
return -1;
if (O_OPOST(tty)) {
switch (c) {
case '\n':
if (O_ONLRET(tty))
tty->column = 0;
if (O_ONLCR(tty)) {
if (LEFT(&tty->write_q) < 2)
return -1;
put_tty_queue('\r', &tty->write_q);
tty->column = 0;
}
tty->canon_column = tty->column;
break;
case '\r':
if (O_ONOCR(tty) && tty->column == 0)
return 0;
if (O_OCRNL(tty)) {
c = '\n';
if (O_ONLRET(tty))
tty->canon_column = tty->column = 0;
break;
}
tty->canon_column = tty->column = 0;
break;
case '\t':
if (O_TABDLY(tty) == XTABS) {
if (LEFT(&tty->write_q) < 8)
return -1;
do
put_tty_queue(' ', &tty->write_q);
while (++tty->column % 8);
return 0;
}
tty->column = (tty->column | 7) + 1;
break;
case '\b':
if (tty->column > 0)
tty->column--;
break;
default:
if (O_OLCUC(tty))
c = toupper(c);
if (!iscntrl(c))
tty->column++;
break;
}
}
put_tty_queue(c, &tty->write_q);
return 0;
}
