[PATCH v4 2/2] selftests: tmpfs: Add kselftest support to tmpfs

[Shivam Chaudhary <cvam0000@gmail.com>]

Replace direct error handling with 'ksft_test_result_*',
'ksft_print_msg' and KSFT_SKIP  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
  ok 1 # SKIP This test needs root to run

- With root
 TAP version 13
1..1
  unshare(): Creat new mount namespace: Success.
  mount(): Root filesystem private mount: Success
  mount(): Mounting tmpfs on /tmp: Success
  openat(): Open first temporary file: Success
  linkat(): Linking the temporary file: Success
  openat(): Opening the second temporary file: Success
  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      | 66 ++++++++++++++-----
 1 file changed, 49 insertions(+), 17 deletions(-)

diff --git a/tools/testing/selftests/tmpfs/bug-link-o-tmpfile.c b/tools/testing/selftests/tmpfs/bug-link-o-tmpfile.c
index cdab1e8c0392..f2e6a5b20698 100644
--- a/tools/testing/selftests/tmpfs/bug-link-o-tmpfile.c
+++ b/tools/testing/selftests/tmpfs/bug-link-o-tmpfile.c
@@ -42,39 +42,71 @@ int main(void)
 
 	if (unshare(CLONE_NEWNS) == -1) {
 		if (errno == ENOSYS || errno == EPERM) {
-			fprintf(stderr, "error: unshare, errno %d\n", errno);
-			return 4;
+			ksft_print_msg("unshare() error: unshare, errno %d\n", errno);
+			exit(KSFT_SKIP);
+
+		}
+		else{
+			fprintf(stderr, "unshare() error: unshare, errno %d\n", errno);
+			return 1;
+
 		}
-		fprintf(stderr, "error: unshare, errno %d\n", errno);
-		return 1;
+	} 
+	
+	else {
+		ksft_print_msg("unshare(): Creat new mount namespace: Success.\n");
+
 	}
-	if (mount(NULL, "/", NULL, MS_PRIVATE|MS_REC, NULL) == -1) {
-		fprintf(stderr, "error: mount '/', errno %d\n", errno);
-		return 1;
+
+
+
+	if (mount(NULL, "/", NULL, MS_PRIVATE | MS_REC, NULL) == -1) {
+		ksft_print_msg("mount() error: Root filesystem private mount: Fail %d\n", errno);
+		exit(KSFT_SKIP);
+	} else {
+		ksft_print_msg("mount(): Root filesystem private mount: Success\n");
 	}
 
+
 	/* 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_print_msg("mount() error: Mounting tmpfs on /tmp: Fail %d\n", errno);
+		exit(KSFT_SKIP);
+	} else {
+		ksft_print_msg("mount(): Mounting tmpfs on /tmp: Success\n");
 	}
 
-	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_print_msg("openat() error: Open first temporary file: Fail %d\n", errno);
+		exit(KSFT_SKIP);
+	} else {
+		ksft_print_msg("openat(): Open first temporary file: Success\n");
 	}
+
+
 	if (linkat(fd, "", AT_FDCWD, "/tmp/1", AT_EMPTY_PATH) == -1) {
-		fprintf(stderr, "error: linkat, errno %d\n", errno);
-		return 1;
+		ksft_print_msg("linkat() error: Linking the temporary file: Fail %d\n", errno);
+		/* Ensure fd is closed on failure */
+		close(fd); 
+		exit(KSFT_SKIP);
+	} else {
+		ksft_print_msg("linkat(): Linking the temporary file: Success\n");
 	}
 	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_print_msg("openat() error: Opening the second temporary file: Fail %d\n", errno);
+		exit(KSFT_SKIP);
+	} else {
+		ksft_print_msg("openat(): Opening the second temporary file: Success\n");
 	}
 
+    ksft_test_result_pass("Test : Success\n");
+	ksft_exit_pass();
 	return 0;
 }
+
-- 
2.45.2