tty: some ICANON magic is in the wrong places

[linux-2.6-omap-h63xx.git] / drivers / char / n_tty.c

diff --git a/drivers/char/n_tty.c b/drivers/char/n_tty.c
index 708c2b1dbe51068a5d1b91ba27d38d79d0c39308..b4f5dccad2a641f87cfe074cbeec5d83613c7b96 100644 (file)
--- a/drivers/char/n_tty.c
+++ b/drivers/char/n_tty.c
@@ -1011,8 +1011,20 @@ int is_ignored(int sig)
 
 static void n_tty_set_termios(struct tty_struct *tty, struct ktermios *old)
 {
-       if (!tty)
-               return;
+       int canon_change = 1;
+       BUG_ON(!tty);
+
+       if (old)
+               canon_change = (old->c_lflag ^ tty->termios->c_lflag) & ICANON;
+       if (canon_change) {
+               memset(&tty->read_flags, 0, sizeof tty->read_flags);
+               tty->canon_head = tty->read_tail;
+               tty->canon_data = 0;
+               tty->erasing = 0;
+       }
+
+       if (canon_change && !L_ICANON(tty) && tty->read_cnt)
+               wake_up_interruptible(&tty->read_wait);
 
        tty->icanon = (L_ICANON(tty) != 0);
        if (test_bit(TTY_HW_COOK_IN, &tty->flags)) {
@@ -1573,6 +1585,43 @@ static unsigned int normal_poll(struct tty_struct *tty, struct file *file,
        return mask;
 }
 
+static unsigned long inq_canon(struct tty_struct *tty)
+{
+       int nr, head, tail;
+
+       if (!tty->canon_data || !tty->read_buf)
+               return 0;
+       head = tty->canon_head;
+       tail = tty->read_tail;
+       nr = (head - tail) & (N_TTY_BUF_SIZE-1);
+       /* Skip EOF-chars.. */
+       while (head != tail) {
+               if (test_bit(tail, tty->read_flags) &&
+                   tty->read_buf[tail] == __DISABLED_CHAR)
+                       nr--;
+               tail = (tail+1) & (N_TTY_BUF_SIZE-1);
+       }
+       return nr;
+}
+
+static int n_tty_ioctl(struct tty_struct *tty, struct file *file,
+                      unsigned int cmd, unsigned long arg)
+{
+       int retval;
+
+       switch (cmd) {
+       case TIOCOUTQ:
+               return put_user(tty_chars_in_buffer(tty), (int __user *) arg);
+       case TIOCINQ:
+               retval = tty->read_cnt;
+               if (L_ICANON(tty))
+                       retval = inq_canon(tty);
+               return put_user(retval, (unsigned int __user *) arg);
+       default:
+               return n_tty_ioctl_helper(tty, file, cmd, arg);
+       }
+}
+
 struct tty_ldisc_ops tty_ldisc_N_TTY = {
        .magic           = TTY_LDISC_MAGIC,
        .name            = "n_tty",