[LTP] [PATCH v2] Refactor mount02 test using new LTP API

[Petr Vorel]

Hi Andrea,

Generally LGTM, few hints below.
...
> +/*\
> + * [Description]
>   *
> - * You should have received a copy of the GNU General Public License along
> - * with this program; if not, write the Free Software Foundation, Inc.,
> - * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
> + * Check for basic errors returned by mount(2) system call.
>   *
> + * - ENODEV if filesystem type not configured
> + * - ENOTBLK if specialfile is not a block device
> + * - EBUSY if specialfile is already mounted or it  cannot  be remounted
> + *   read-only, because it still holds files open for writing.
> + * - EINVAL if specialfile or device is invalid or a remount was attempted,
> + *   while source was not already mounted on target.
> + * - EFAULT if special file or device file points to invalid address space.
> + * - ENAMETOOLONG if pathname was longer than MAXPATHLEN.
> + * - ENOENT if pathname was empty or has a nonexistent component.
> + * - ENOTDIR if not a directory.
>   */

...
> -#include <errno.h>
> +#include "tst_test.h"
>  #include <sys/mount.h>
> -#include <sys/types.h>
> -#include <sys/stat.h>
>  #include <sys/sysmacros.h>
This header is not needed.

> -#include <fcntl.h>
> -#include "test.h"
> -#include "safe_macros.h"
> -
> -static void setup(void);
> -static void cleanup(void);

> -char *TCID = "mount02";
> -
> -#define DIR_MODE	(S_IRWXU | S_IRUSR | S_IXUSR | S_IRGRP | S_IXGRP)
> -#define FILE_MODE	(S_IRWXU | S_IRWXG | S_IRWXO)
> +#define MNTPOINT "mntpoint"
#define TEST_FILE MNTPOINT"/file"

And use it later in pre_create_file()
	fd = SAFE_OPEN(TEST_FILE, O_CREAT | O_RDWR, 0700);

>  static char path[PATH_MAX + 2];
>  static const char *long_path = path;
> +static const char *device;
>  static const char *fs_type;
> +static const char *null;
>  static const char *wrong_fs_type = "error";
> -static const char *mntpoint = "mntpoint";
> -static const char *device;
> -static const char *null = NULL;
> -static const char *fault = (void*)-1;
> +static const char *mntpoint = MNTPOINT;
> +static const char *fault = (void *)-1;
Hopefully this will work everywhere.
I wonder if this is a better approach:

tst_get_bad_addr(NULL);

>  static const char *nonexistent = "nonexistent";
>  static const char *char_dev = "char_device";
>  static const char *file = "filename";
>  static int fd;

> -static void do_umount(void);
> -static void close_umount(void);
> -static void do_mount(void);
> -static void mount_open(void);
> +static void pre_mount(void);
> +static void post_umount(void);
> +static void pre_create_file(void);
> +static void post_delete_file(void);

>  static struct test_case {
>  	const char **device;
>  	const char **mntpoint;
>  	const char **fs_type;
> +	const char *fs_str;
We usually use *desc for this.

>  	unsigned long flag;
>  	int exp_errno;
>  	void (*setup)(void);
>  	void (*cleanup)(void);
> -} tc[] = {
> -	{&device, &mntpoint, &wrong_fs_type, 0, ENODEV, NULL, NULL},
> -	{&char_dev, &mntpoint, &fs_type, 0, ENOTBLK, NULL, NULL},
> -	{&device, &mntpoint, &fs_type, 0, EBUSY, do_mount, do_umount},
> -	{&device, &mntpoint, &fs_type, MS_REMOUNT | MS_RDONLY, EBUSY,
> -	 mount_open, close_umount},
> -	{&null, &mntpoint, &fs_type, 0, EINVAL, NULL, NULL},
> -	{&device, &mntpoint, &null, 0, EINVAL, NULL, NULL},
> -	{&device, &mntpoint, &fs_type, MS_REMOUNT, EINVAL, NULL, NULL},
> -	{&fault, &mntpoint, &fs_type, 0, EFAULT, NULL, NULL},
> -	{&device, &mntpoint, &fault, 0, EFAULT, NULL, NULL},
> -	{&device, &long_path, &fs_type, 0, ENAMETOOLONG, NULL, NULL},
> -	{&device, &nonexistent, &fs_type, 0, ENOENT, NULL, NULL},
> -	{&device, &file, &fs_type, 0, ENOTDIR, NULL, NULL},
> +} test_cases[] = {
> +	{&device, &mntpoint, &wrong_fs_type, "wrong FS type", 0, ENODEV, NULL, NULL},
> +	{&char_dev, &mntpoint, &fs_type, "char device", 0, ENOTBLK, NULL, NULL},
> +	{&device, &mntpoint, &fs_type, "mounted folder", 0, EBUSY, pre_mount, post_umount},
> +	{&device, &mntpoint, &fs_type, "mounted folder containing file", MS_REMOUNT | MS_RDONLY, EBUSY, pre_create_file, post_delete_file},
> +	{&null, &mntpoint, &fs_type, "invalid device", 0, EINVAL, NULL, NULL},
> +	{&device, &mntpoint, &null, "invalid device type", 0, EINVAL, NULL, NULL},
> +	{&device, &mntpoint, &fs_type, "mounted folder", MS_REMOUNT, EINVAL, NULL, NULL},
> +	{&fault, &mntpoint, &fs_type, "fault device", 0, EFAULT, NULL, NULL},
> +	{&device, &mntpoint, &fault, "fault device type", 0, EFAULT, NULL, NULL},
> +	{&device, &long_path, &fs_type, "long name", 0, ENAMETOOLONG, NULL, NULL},
> +	{&device, &nonexistent, &fs_type, "non existant folder", 0, ENOENT, NULL, NULL},
> +	{&device, &file, &fs_type, "file", 0, ENOTDIR, NULL, NULL},

I know this was used before and you just extend it, but if we use less of const
(it'd have to be casted at least for .fs_type as tst_device->fs_type is const),
we could use named constants easily:

} test_cases[] = {
	{ .fs_type = &wrong_fs_type, .desc = "wrong FS type", .exp_errno = ENODEV},
	{ .device = &char_dev, .desc = "char device", .exp_errno = ENOTBLK},
	{ .desc = "mounted folder", .exp_errno = EBUSY, .setup = pre_mount,
		.cleanup = post_umount},
	{ .desc = "mounted folder containing file", .flag = MS_REMOUNT | MS_RDONLY,
		.exp_errno = EBUSY, .setup = pre_create_file, .cleanup = post_delete_file},
	{ .device = &null, .desc = "invalid device", .exp_errno = EINVAL},
	{ .mntpoint = &null, .desc = "invalid device type", .exp_errno = EINVAL},
	{ .desc = "mounted folder", MS_REMOUNT, .exp_errno = EINVAL},
	{ .device = &fault, .desc = "fault device", .exp_errno = EFAULT},
	{ .fs_type = &fault, .desc = "fault device type", .exp_errno = EFAULT},
	{ .mntpoint = &long_path, .desc = "long name", .exp_errno = ENAMETOOLONG},
	{ .mntpoint = &nonexistent, .desc = "non existant folder", .exp_errno = ENOENT},
	{ .mntpoint = &file, .desc = "file", .exp_errno = ENOTDIR},
};

You can happily ignore that, but using field name in struct initializers is 1)
much readable 2) allows to avoid 0 and NULL. Well, we'd have to init some values in run()
- see below (or just add all of them in struct, and at least avoid 0 and  NULL, NULL).

static void run(unsigned int i)
{
	struct test_case *tc = &test_cases[i];

	if (!tc->device)
		tc->device = &device;

	if (!tc->mntpoint)
		tc->mntpoint = &mntpoint;

	if (!tc->fs_type)
		tc->fs_type = &fs_type;

...
> +static struct tst_test test = {
> +	.tcnt = ARRAY_SIZE(test_cases),
> +	.test = run,
> +	.setup = setup,
> +	.cleanup = cleanup,
> +	.needs_root = 1,
> +	.needs_tmpdir = 1,
no need for .needs_tmpdir

Kind regards,
Petr
> +	.format_device = 1,
> +	.mntpoint = MNTPOINT,
> +};