s390/3215: fix tty output containing tabs (e512d56c) · Commits · 戴 / test

git commit "n_tty: do O_ONLCR translation as a single write" surfaced a bug in the 3215 device driver. In combination this broke tab expansion for tty ouput. The cause is an asymmetry in the behaviour of tty3215_ops->write vs tty3215_ops->put_char. The put_char function scans for '\t' but the write function does not. As the driver has logic for the '\t' expansion remove XTABS from c_oflag of the initial termios as well. Reported-by:

Stephen Powell <zlinuxman@wowway.com> Signed-off-by:

Martin Schwidefsky <schwidefsky@de.ibm.com>

drivers/s390/char/con3215.c

+17 −3

Original line number	Diff line number	Diff line
		@@ -1035,12 +1035,26 @@ static int tty3215_write(struct tty_struct * tty,
		const unsigned char *buf, int count)
		{
		struct raw3215_info *raw;
		int i, written;

		if (!tty)
		return 0;
		raw = (struct raw3215_info *) tty->driver_data;
		raw3215_write(raw, buf, count);
		return count;
		written = count;
		while (count > 0) {
		for (i = 0; i < count; i++)
		if (buf[i] == '\t' \|\| buf[i] == '\n')
		break;
		raw3215_write(raw, buf, i);
		count -= i;
		buf += i;
		if (count > 0) {
		raw3215_putchar(raw, *buf);
		count--;
		buf++;
		}
		}
		return written;
		}

		/*
		@@ -1188,7 +1202,7 @@ static int __init tty3215_init(void)
		driver->subtype = SYSTEM_TYPE_TTY;
		driver->init_termios = tty_std_termios;
		driver->init_termios.c_iflag = IGNBRK \| IGNPAR;
		driver->init_termios.c_oflag = ONLCR \| XTABS;
		driver->init_termios.c_oflag = ONLCR;
		driver->init_termios.c_lflag = ISIG;
		driver->flags = TTY_DRIVER_REAL_RAW;
		tty_set_operations(driver, &tty3215_ops);

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