n_tty: move lnext handling

Move lnext handling from __receive_buf to n_tty_receive_buf_standard. It
simplifies the handling as it needs not fetching 'flag' and decrement
'count' in __receive_buf. Instead, all this is left up to the loop in
n_tty_receive_buf_standard which already does that.

This way, no need to repeat the action when n_tty_receive_char_special
returns true -- ldata->lnext is set there in that case, so the 'if
(ldata->lnext)' check is sufficient. The next patch will switch
n_tty_receive_char_special to return 'void'.

The result is much simplified code flow.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210505091928.22010-7-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c
index f0db3f4..d40844b 100644 (file)
--- a/drivers/tty/n_tty.c
+++ b/drivers/tty/n_tty.c
@@ -1538,6 +1538,12 @@ static void n_tty_receive_buf_standard(struct tty_struct *tty,
        while (count--) {
                if (fp)
                        flag = *fp++;
+
+               if (ldata->lnext) {
+                       n_tty_receive_char_lnext(tty, *cp++, flag);
+                       continue;
+               }
+
                if (likely(flag == TTY_NORMAL)) {
                        unsigned char c = *cp++;
 
@@ -1551,12 +1557,8 @@ static void n_tty_receive_buf_standard(struct tty_struct *tty,
                        }
                        if (!test_bit(c, ldata->char_map))
                                n_tty_receive_char(tty, c);
-                       else if (n_tty_receive_char_special(tty, c) && count) {
-                               if (fp)
-                                       flag = *fp++;
-                               n_tty_receive_char_lnext(tty, *cp++, flag);
-                               count--;
-                       }
+                       else
+                               n_tty_receive_char_special(tty, c);
                } else
                        n_tty_receive_char_flagged(tty, *cp++, flag);
        }
@@ -1575,15 +1577,6 @@ static void __receive_buf(struct tty_struct *tty, const unsigned char *cp,
        else if (tty->closing && !L_EXTPROC(tty))
                n_tty_receive_buf_closing(tty, cp, fp, count);
        else {
-               if (ldata->lnext) {
-                       char flag = TTY_NORMAL;
-
-                       if (fp)
-                               flag = *fp++;
-                       n_tty_receive_char_lnext(tty, *cp++, flag);
-                       count--;
-               }
-
                n_tty_receive_buf_standard(tty, cp, fp, count);
 
                flush_echoes(tty);