[LTP] [PATCH v2] pty: fix some issues in pty02

[Xiao Yang]

On 2018/08/17 10:26, Li Wang wrote:
> 1. Add EXTPROC into lapi
>
> 2. Exit the test with TCONF if we get EINVAL from tcsetattr()
>
> 3. Write newline to ptmx to avoid read() on pts to block
>
> 4. Using tcgetattr() to get attributes before re-setting it
>
> Fix this error:
>    tst_test.c:1015: INFO: Timeout per run is 0h 50m 00s
>    pty02.c:42: BROK: tcsetattr() failed: EINVAL
>
> POSIX.1 General description:
>   Changes the attributes associated with a terminal. New attributes are
>   specified with a termios control structure. Programs should always
>   issue a tcgetattr() first, modify the desired fields, and then issue
>   a tcsetattr(). tcsetattr() should never be issued using a termios
>   structure that was not obtained using tcgetattr(). tcsetattr() should
>   use only a termios structure that was obtained by tcgetattr().
>
> Signed-off-by: Li Wang <liwang@redhat.com>
> Cc: Eric Biggers <ebiggers@google.com>
> Cc: Cyril Hrubis <chrubis@suse.cz>
> Cc: Xiao Yang <yangx.jy@cn.fujitsu.com>
> Cc: Jinhui huang <huangjh.jy@cn.fujitsu.com>
> ---
>
> Notes:
>     v1 -> v2:
>     
>     * use TST_RET and TST_ERR
>     * do SAFE_WRITE(1, ptmx, "A\n", 2) instead
>     * reword the code comments
>
>  include/lapi/termbits.h      | 25 +++++++++++++++++++++++++
>  testcases/kernel/pty/pty02.c | 21 +++++++++++++++++----
>  2 files changed, 42 insertions(+), 4 deletions(-)
>  create mode 100644 include/lapi/termbits.h
>
> diff --git a/include/lapi/termbits.h b/include/lapi/termbits.h
> new file mode 100644
> index 0000000..23ad5a7
> --- /dev/null
> +++ b/include/lapi/termbits.h
> @@ -0,0 +1,25 @@
> +/*
> + * Copyright (c) 2018 Linux Test Project
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License as
> + * published by the Free Software Foundation; either version 2 of
> + * the License, or (at your option) any later version.
> + *
> + * This program is distributed in the hope that it would be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write the Free Software Foundation
> + */
> +
> +#ifndef LAPI_TERMBITS_H__
> +#define LAPI_TERMBITS_H__
> +
> +#ifndef EXTPROC
> +# define EXTPROC     0200000
> +#endif
> +
> +#endif
> diff --git a/testcases/kernel/pty/pty02.c b/testcases/kernel/pty/pty02.c
> index fd3d26b..841e233 100644
> --- a/testcases/kernel/pty/pty02.c
> +++ b/testcases/kernel/pty/pty02.c
> @@ -25,27 +25,40 @@
>   */
>  
>  #include <stdlib.h>
> +#include <errno.h>
>  #include <termio.h>
>  
>  #include "tst_test.h"
> +#include "lapi/termbits.h"
>  
>  static void do_test(void)
>  {
> -	struct termios io = { .c_lflag = EXTPROC | ICANON };
> +	struct termios io;
>  	int ptmx, pts;
>  	char c = 'A';
>  	int nbytes;
>  
>  	ptmx = SAFE_OPEN("/dev/ptmx", O_WRONLY);
>  
> -	if (tcsetattr(ptmx, TCSANOW, &io) != 0)
> -		tst_brk(TBROK | TERRNO, "tcsetattr() failed");
> +	if (tcgetattr(ptmx, &io) != 0)
> +		tst_brk(TBROK | TERRNO, "tcgetattr() failed");
> +
> +	io.c_lflag = EXTPROC | ICANON;
> +
> +	TEST(tcsetattr(ptmx, TCSANOW, &io));
> +	if (TEST_RET == -1) {
> +		if (TEST_ERR == EINVAL)
> +			tst_res(TCONF, "tcsetattr(, , EXTPROC | ICANON) is not supported");
Hi Li,

Should we use tst_brk(TCONF, ...) instead?

Thanks,
Xiao Yang
> +		else
> +			tst_brk(TBROK | TERRNO, "tcsetattr() failed");
> +	}
>  
>  	if (unlockpt(ptmx) != 0)
>  		tst_brk(TBROK | TERRNO, "unlockpt() failed");
>  
>  	pts = SAFE_OPEN(ptsname(ptmx), O_RDONLY);
> -	SAFE_WRITE(1, ptmx, &c, 1);
> +	/* write newline to ptmx to avoid read() on pts to block */
> +	SAFE_WRITE(1, ptmx, "A\n", 2);
>  	SAFE_READ(1, pts, &c, 1);
>  
>  	tst_res(TINFO, "Calling FIONREAD, this will hang in n_tty_ioctl() if the bug is present...");