[LTP] [PATCH v1 3/4] syscalls/shmget05: Add test for /proc/sys/kernel/shm_next_id

[xuyang2018.jy@fujitsu.com]

Hi Cyril

Since the previous patches have been merged, this patch can be continued.

Best Regards
Yang Xu
> This case is similar to msgget04.c.
> 
> Signed-off-by: Yang Xu<xuyang2018.jy@fujitsu.com>
> ---
>   runtest/syscalls                              |  1 +
>   runtest/syscalls-ipc                          |  1 +
>   .../kernel/syscalls/ipc/shmget/.gitignore     |  1 +
>   .../kernel/syscalls/ipc/shmget/shmget05.c     | 69 +++++++++++++++++++
>   4 files changed, 72 insertions(+)
>   create mode 100644 testcases/kernel/syscalls/ipc/shmget/shmget05.c
> 
> diff --git a/runtest/syscalls b/runtest/syscalls
> index 2dff25984..63d821e53 100644
> --- a/runtest/syscalls
> +++ b/runtest/syscalls
> @@ -1402,6 +1402,7 @@ shmdt02 shmdt02
>   shmget02 shmget02
>   shmget03 shmget03
>   shmget04 shmget04
> +shmget05 shmget05
> 
>   sigaction01 sigaction01
>   sigaction02 sigaction02
> diff --git a/runtest/syscalls-ipc b/runtest/syscalls-ipc
> index b3bd37923..ff0364704 100644
> --- a/runtest/syscalls-ipc
> +++ b/runtest/syscalls-ipc
> @@ -67,3 +67,4 @@ shmdt02 shmdt02
>   shmget02 shmget02
>   shmget03 shmget03
>   shmget04 shmget04
> +shmget05 shmget05
> diff --git a/testcases/kernel/syscalls/ipc/shmget/.gitignore b/testcases/kernel/syscalls/ipc/shmget/.gitignore
> index c57df68f5..6f08529f8 100644
> --- a/testcases/kernel/syscalls/ipc/shmget/.gitignore
> +++ b/testcases/kernel/syscalls/ipc/shmget/.gitignore
> @@ -1,3 +1,4 @@
>   /shmget02
>   /shmget03
>   /shmget04
> +/shmget05
> diff --git a/testcases/kernel/syscalls/ipc/shmget/shmget05.c b/testcases/kernel/syscalls/ipc/shmget/shmget05.c
> new file mode 100644
> index 000000000..601609648
> --- /dev/null
> +++ b/testcases/kernel/syscalls/ipc/shmget/shmget05.c
> @@ -0,0 +1,69 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Copyright (c) 2021 FUJITSU LIMITED. All rights reserved.
> + * Author: Yang Xu<xuyang2018.jy@fujitsu.com>
> + */
> +
> +/*\
> + * [Description]
> + *
> + * It is a basic test about shm_next_id.
> + *
> + * shm_next_id specifies desired id for next allocated IPC shared memory. By
> + * default they are equal to -1, which means generic allocation logic.
> + * Possible values to set are in range {0..INT_MAX}.
> + * Toggle with non-default value will be set back to -1 by kernel after
> + * successful IPC object allocation.
> + */
> +
> +#include<errno.h>
> +#include<string.h>
> +#include<sys/types.h>
> +#include<sys/ipc.h>
> +#include<sys/shm.h>
> +#include "tst_test.h"
> +#include "tst_safe_sysv_ipc.h"
> +#include "libnewipc.h"
> +
> +#define NEXT_ID_PATH "/proc/sys/kernel/shm_next_id"
> +static int shm_id, pid;
> +static key_t shmkey;
> +
> +static void verify_shmget(void)
> +{
> +	SAFE_FILE_PRINTF(NEXT_ID_PATH, "%d", pid);
> +
> +	shm_id = SAFE_SHMGET(shmkey, SHM_SIZE, SHM_RW | IPC_CREAT);
> +	if (shm_id == pid)
> +		tst_res(TPASS, "shm_next_id succeeded, shm id %d", pid);
> +	else
> +		tst_res(TFAIL, "shm_next_id failed, expected id %d, but got %d", pid, shm_id);
> +
> +	TST_ASSERT_INT(NEXT_ID_PATH, -1);
> +	SAFE_SHMCTL(shm_id, IPC_RMID, NULL);
> +	pid++;
> +}
> +
> +static void setup(void)
> +{
> +	shmkey = GETIPCKEY();
> +	pid = getpid();
> +}
> +
> +static void cleanup(void)
> +{
> +	if (shm_id != -1)
> +		SAFE_SHMCTL(shm_id, IPC_RMID, NULL);
> +}
> +
> +static struct tst_test test = {
> +	.needs_tmpdir = 1,
> +	.setup = setup,
> +	.cleanup = cleanup,
> +	.test_all = verify_shmget,
> +	.needs_kconfigs = (const char *[]) {
> +		"CONFIG_CHECKPOINT_RESTORE=y",
> +		NULL
> +	},
> +	.needs_root = 1,
> +};