tty: n_tty: move newline handling to a separate function

Currently, n_tty handles the newline in a label in
n_tty_receive_char_canon(). That is invoked from two more places. Split
this code to a separate function and avoid the label in this case.

This makes the code flow more understandable.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230827074147.2287-9-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c
index 0149dc9..632516d 100644 (file)
--- a/drivers/tty/n_tty.c
+++ b/drivers/tty/n_tty.c
@@ -1262,6 +1262,17 @@ static bool n_tty_receive_char_flow_ctrl(struct tty_struct *tty, unsigned char c
        return true;
 }
 
+static void n_tty_receive_handle_newline(struct tty_struct *tty, u8 c)
+{
+       struct n_tty_data *ldata = tty->disc_data;
+
+       set_bit(MASK(ldata->read_head), ldata->read_flags);
+       put_tty_queue(c, ldata);
+       smp_store_release(&ldata->canon_head, ldata->read_head);
+       kill_fasync(&tty->fasync, SIGIO, POLL_IN);
+       wake_up_interruptible_poll(&tty->read_wait, EPOLLIN | EPOLLRDNORM);
+}
+
 static bool n_tty_receive_char_canon(struct tty_struct *tty, u8 c)
 {
        struct n_tty_data *ldata = tty->disc_data;
@@ -1308,12 +1319,16 @@ static bool n_tty_receive_char_canon(struct tty_struct *tty, u8 c)
                        echo_char_raw('\n', ldata);
                        commit_echoes(tty);
                }
-               goto handle_newline;
+               n_tty_receive_handle_newline(tty, c);
+
+               return true;
        }
 
        if (c == EOF_CHAR(tty)) {
                c = __DISABLED_CHAR;
-               goto handle_newline;
+               n_tty_receive_handle_newline(tty, c);
+
+               return true;
        }
 
        if ((c == EOL_CHAR(tty)) ||
@@ -1335,12 +1350,8 @@ static bool n_tty_receive_char_canon(struct tty_struct *tty, u8 c)
                if (c == (unsigned char) '\377' && I_PARMRK(tty))
                        put_tty_queue(c, ldata);
 
-handle_newline:
-               set_bit(MASK(ldata->read_head), ldata->read_flags);
-               put_tty_queue(c, ldata);
-               smp_store_release(&ldata->canon_head, ldata->read_head);
-               kill_fasync(&tty->fasync, SIGIO, POLL_IN);
-               wake_up_interruptible_poll(&tty->read_wait, EPOLLIN | EPOLLRDNORM);
+               n_tty_receive_handle_newline(tty, c);
+
                return true;
        }