[PATCH v5 2/2] selftests: tmpfs: Add kselftest support to tmpfs

[Shivam Chaudhary <cvam0000@gmail.com>]

Replace direct error handling with 'ksft_test_result_*',
'ksft_exit_fail_msg' macros for better reporting.

Test logs:

Before change:
- Without root
 error: unshare, errno 1

- With root
 No, output

After change:
- Without root
TAP version 13
1..1
Bail out! Error : Need to run as root# Planned tests != run tests (1 != 0)
Totals: pass:0 fail:0 xfail:0 xpass:0 skip:0 error:0

- With root
TAP version 13
1..1
ok 1 Test : Success
Totals: pass:1 fail:0 xfail:0 xpass:0 skip:0 error:0

Signed-off-by: Shivam Chaudhary <cvam0000@gmail.com>
---
 .../selftests/tmpfs/bug-link-o-tmpfile.c      | 49 ++++++++++---------
 1 file changed, 26 insertions(+), 23 deletions(-)

diff --git a/tools/testing/selftests/tmpfs/bug-link-o-tmpfile.c b/tools/testing/selftests/tmpfs/bug-link-o-tmpfile.c
index f0b36e7a152e..c3a8c9c50c8a 100644
--- a/tools/testing/selftests/tmpfs/bug-link-o-tmpfile.c
+++ b/tools/testing/selftests/tmpfs/bug-link-o-tmpfile.c
@@ -40,39 +40,42 @@ int main(void)
 
 	if (unshare(CLONE_NEWNS) == -1) {
 		if (errno == ENOSYS || errno == EPERM) {
-			fprintf(stderr, "error: unshare, errno %d\n", errno);
-			return 4;
+			ksft_test_result_skip("unshare() error: unshare, errno %d\n", errno);	
 		}
-		fprintf(stderr, "error: unshare, errno %d\n", errno);
-		return 1;
-	}
-	if (mount(NULL, "/", NULL, MS_PRIVATE|MS_REC, NULL) == -1) {
-		fprintf(stderr, "error: mount '/', errno %d\n", errno);
-		return 1;
-	}
+		else{
+			ksft_exit_fail_msg("unshare() error: unshare, errno %d\n", errno);
+		}
+	} 
+	
+	if (mount(NULL, "/", NULL, MS_PRIVATE | MS_REC, NULL) == -1) {
+		ksft_exit_fail_msg("mount() error: Root filesystem private mount: Fail %d\n", errno);
+	} 
+
 
 	/* Our heroes: 1 root inode, 1 O_TMPFILE inode, 1 permanent inode. */
 	if (mount(NULL, "/tmp", "tmpfs", 0, "nr_inodes=3") == -1) {
-		fprintf(stderr, "error: mount tmpfs, errno %d\n", errno);
-		return 1;
-	}
+		ksft_exit_fail_msg("mount() error: Mounting tmpfs on /tmp: Fail %d\n", errno);
+	} 
 
-	fd = openat(AT_FDCWD, "/tmp", O_WRONLY|O_TMPFILE, 0600);
+	fd = openat(AT_FDCWD, "/tmp", O_WRONLY | O_TMPFILE, 0600);
 	if (fd == -1) {
-		fprintf(stderr, "error: open 1, errno %d\n", errno);
-		return 1;
-	}
+		ksft_exit_fail_msg("openat() error: Open first temporary file: Fail %d\n", errno);
+	} 
+
 	if (linkat(fd, "", AT_FDCWD, "/tmp/1", AT_EMPTY_PATH) == -1) {
-		fprintf(stderr, "error: linkat, errno %d\n", errno);
-		return 1;
-	}
+		ksft_exit_fail_msg("linkat() error: Linking the temporary file: Fail %d\n", errno);
+		/* Ensure fd is closed on failure */
+		close(fd); 
+	} 
 	close(fd);
 
-	fd = openat(AT_FDCWD, "/tmp", O_WRONLY|O_TMPFILE, 0600);
+
+	fd = openat(AT_FDCWD, "/tmp", O_WRONLY | O_TMPFILE, 0600);
 	if (fd == -1) {
-		fprintf(stderr, "error: open 2, errno %d\n", errno);
-		return 1;
-	}
+		ksft_exit_fail_msg("openat() error: Opening the second temporary file: Fail %d\n", errno);
+	} 
 
+    ksft_test_result_pass("Test : Success\n");
+	ksft_exit_pass();
 	return 0;
 }
-- 
2.45.2