[PATCH 22/27] selftests/landlock: Fix messages and comments in helper programs

["Günther Noack" <gnoack3000@gmail.com>]

* sandbox-and-launch: Describe the actual argument order.
* sandbox-and-launch, wait-pipe, wait-pipe-sandbox: Report failed
  read(2) calls as read failures, not write failures.
* wait-pipe-sandbox: Terminate error messages with a newline, and fix
  comments naming "." instead of the opened "/".

Assisted-by: LLM
Signed-off-by: Günther Noack <gnoack3000@gmail.com>
---
 .../selftests/landlock/sandbox-and-launch.c      |  6 +++---
 .../selftests/landlock/wait-pipe-sandbox.c       | 16 ++++++++--------
 tools/testing/selftests/landlock/wait-pipe.c     |  2 +-
 3 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/tools/testing/selftests/landlock/sandbox-and-launch.c b/tools/testing/selftests/landlock/sandbox-and-launch.c
index 3e32e1a51ac5..8b33ddadc63e 100644
--- a/tools/testing/selftests/landlock/sandbox-and-launch.c
+++ b/tools/testing/selftests/landlock/sandbox-and-launch.c
@@ -25,8 +25,8 @@ int main(int argc, char *argv[])
 	char buf;
 
 	/*
-	 * The first argument must be the file descriptor number of a pipe.
-	 * The second argument must be the program to execute.
+	 * The first argument must be the program to execute.  The second and
+	 * third arguments must be the file descriptor numbers of two pipes.
 	 */
 	if (argc != 4) {
 		fprintf(stderr, "Wrong number of arguments (not three)\n");
@@ -67,7 +67,7 @@ int main(int argc, char *argv[])
 
 	/* Waits for the parent to try to umount. */
 	if (read(pipe_parent, &buf, 1) != 1) {
-		perror("Failed to write to the third argument");
+		perror("Failed to read from the third argument");
 		return 1;
 	}
 
diff --git a/tools/testing/selftests/landlock/wait-pipe-sandbox.c b/tools/testing/selftests/landlock/wait-pipe-sandbox.c
index 87dbc9164430..dbc0c2747e9f 100644
--- a/tools/testing/selftests/landlock/wait-pipe-sandbox.c
+++ b/tools/testing/selftests/landlock/wait-pipe-sandbox.c
@@ -31,7 +31,7 @@ static int sync_with(int pipe_child, int pipe_parent)
 
 	/* Waits for the parent do its test. */
 	if (read(pipe_parent, &buf, 1) != 1) {
-		perror("Failed to write to the second argument");
+		perror("Failed to read from the second argument");
 		return 1;
 	}
 
@@ -65,7 +65,7 @@ int main(int argc, char *argv[])
 
 	/* Tries to send a signal, denied by layer1. */
 	if (!kill(getppid(), 0)) {
-		fprintf(stderr, "Successfully sent a signal to the parent");
+		fprintf(stderr, "Successfully sent a signal to the parent\n");
 		return 1;
 	}
 
@@ -88,13 +88,13 @@ int main(int argc, char *argv[])
 
 	/* Tries to send a signal, denied by layer1. */
 	if (!kill(getppid(), 0)) {
-		fprintf(stderr, "Successfully sent a signal to the parent");
+		fprintf(stderr, "Successfully sent a signal to the parent\n");
 		return 1;
 	}
 
-	/* Tries to open ., denied by layer2. */
+	/* Tries to open /, denied by layer2. */
 	if (open("/", O_RDONLY | O_DIRECTORY | O_CLOEXEC) >= 0) {
-		fprintf(stderr, "Successfully opened /");
+		fprintf(stderr, "Successfully opened /\n");
 		return 1;
 	}
 
@@ -115,15 +115,15 @@ int main(int argc, char *argv[])
 	}
 	close(ruleset_fd);
 
-	/* Tries to open ., denied by layer2. */
+	/* Tries to open /, denied by layer2. */
 	if (open("/", O_RDONLY | O_DIRECTORY | O_CLOEXEC) >= 0) {
-		fprintf(stderr, "Successfully opened /");
+		fprintf(stderr, "Successfully opened /\n");
 		return 1;
 	}
 
 	/* Tries to send a signal, denied by layer3. */
 	if (!kill(getppid(), 0)) {
-		fprintf(stderr, "Successfully sent a signal to the parent");
+		fprintf(stderr, "Successfully sent a signal to the parent\n");
 		return 1;
 	}
 
diff --git a/tools/testing/selftests/landlock/wait-pipe.c b/tools/testing/selftests/landlock/wait-pipe.c
index 0dbcd260a0fa..3cfa4dce5f35 100644
--- a/tools/testing/selftests/landlock/wait-pipe.c
+++ b/tools/testing/selftests/landlock/wait-pipe.c
@@ -34,7 +34,7 @@ int main(int argc, char *argv[])
 
 	/* Waits for the parent do its test. */
 	if (read(pipe_parent, &buf, 1) != 1) {
-		perror("Failed to write to the second argument");
+		perror("Failed to read from the second argument");
 		return 1;
 	}
 
-- 
2.56.0