[LTP] [PATCH] msgrcv02: Add negative msgtyp tests

[xuyang2018.jy@fujitsu.com]

Hi Richard
> Test that we do not get higher message types. Also that -1 msgtyp is not
> misinterpreted as INT_MAX by using MSG_EXCEPT.

Other than some unnecessary spaces or empty lines, this patch looks good 
to me.

Reviewed-by: Yang Xu <xuyang2018.jy@fujitsu.com>

Best Regards
Yang Xu
>
> Signed-off-by: Richard Palethorpe<rpalethorpe@suse.com>
> Suggested-by: Cyril Hrubis<chrubis@suse.cz>
> ---
>   .../kernel/syscalls/ipc/msgrcv/msgrcv02.c     | 19 ++++++++++++-------
>   1 file changed, 12 insertions(+), 7 deletions(-)
>
> diff --git a/testcases/kernel/syscalls/ipc/msgrcv/msgrcv02.c b/testcases/kernel/syscalls/ipc/msgrcv/msgrcv02.c
> index cfb7d7446..fba6a5289 100644
> --- a/testcases/kernel/syscalls/ipc/msgrcv/msgrcv02.c
> +++ b/testcases/kernel/syscalls/ipc/msgrcv/msgrcv02.c
> @@ -21,6 +21,8 @@
>    *   msgflg and no message of the requested type existed on the message queue.
>    */
>
> +#define _GNU_SOURCE
> +
>   #include<string.h>
>   #include<sys/wait.h>
>   #include<sys/msg.h>
> @@ -38,7 +40,7 @@ struct passwd *pw;
>   static struct buf {
>   	long type;
>   	char mtext[MSGSIZE];
> -} rcv_buf, snd_buf = {MSGTYPE, "hello"};
> +} rcv_buf, snd_buf = {2, "hello"};
>
>   static struct tcase {
>   	int *id;
> @@ -49,12 +51,15 @@ static struct tcase {
>   	int exp_user;
>   	int exp_err;
>   } tcases[] = {
> -	{&queue_id,&rcv_buf, 4, 1, 0, 0, E2BIG},
> -	{&queue_id,&rcv_buf, MSGSIZE, 1, 0, 1, EACCES},
> -	{&queue_id, NULL, MSGSIZE, 1, 0, 0, EFAULT},
> -	{&bad_id,&rcv_buf, MSGSIZE, 1, 0, 0, EINVAL},
> -	{&queue_id,&rcv_buf, -1, 1, 0, 0, EINVAL},
> -	{&queue_id,&rcv_buf, MSGSIZE, 2, IPC_NOWAIT, 0, ENOMSG},
> +	{&queue_id,&rcv_buf, MSGSIZE - 1, 2, 0, 0, E2BIG},
> +	{&queue_id,&rcv_buf, MSGSIZE,     2, 0, 1, EACCES},
> +	{&queue_id, NULL,     MSGSIZE,     2, 0, 0, EFAULT},
> +	{&bad_id,&rcv_buf, MSGSIZE,     2, 0, 0, EINVAL},
> +	{&queue_id,&rcv_buf, -1,          2, 0, 0, EINVAL},
> +
> +	{&queue_id,&rcv_buf, MSGSIZE,  3, IPC_NOWAIT,              0, ENOMSG},
> +	{&queue_id,&rcv_buf, MSGSIZE, -1, IPC_NOWAIT,              0, ENOMSG},
> +	{&queue_id,&rcv_buf, MSGSIZE, -1, IPC_NOWAIT | MSG_EXCEPT, 0, ENOMSG},
>   };
>
>   static void verify_msgrcv(struct tcase *tc)