[PATCH v3 2/6] libtracefs: Change get name API to return constant string

["Tzvetomir Stoyanov (VMware)" <tz.stoyanov@xxxxxxxxx>]

The tracefs_instance_get_name() API returns a pointer to internal
string. This string is not meant to be changed by the API callers,
that's why it should be constant.

Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@xxxxxxxxx>
---
 include/tracefs/tracefs.h      |  2 +-
 lib/tracefs/tracefs-events.c   | 12 ++----------
 lib/tracefs/tracefs-instance.c |  2 +-
 tracecmd/trace-record.c        |  2 +-
 utest/tracefs-utest.c          |  2 +-
 5 files changed, 6 insertions(+), 14 deletions(-)

diff --git a/include/tracefs/tracefs.h b/include/tracefs/tracefs.h
index 8ee7ba6e..1cf8de48 100644
--- a/include/tracefs/tracefs.h
+++ b/include/tracefs/tracefs.h
@@ -24,7 +24,7 @@ struct tracefs_instance *tracefs_instance_alloc(const char *name);
 void tracefs_instance_free(struct tracefs_instance *instance);
 int tracefs_instance_create(struct tracefs_instance *instance);
 int tracefs_instance_destroy(struct tracefs_instance *instance);
-char *tracefs_instance_get_name(struct tracefs_instance *instance);
+const char *tracefs_instance_get_name(struct tracefs_instance *instance);
 char *
 tracefs_instance_get_file(struct tracefs_instance *instance, const char *file);
 char *tracefs_instance_get_dir(struct tracefs_instance *instance);
diff --git a/lib/tracefs/tracefs-events.c b/lib/tracefs/tracefs-events.c
index 8e825f50..6b796382 100644
--- a/lib/tracefs/tracefs-events.c
+++ b/lib/tracefs/tracefs-events.c
@@ -481,11 +481,7 @@ next_event:
 			failure = ret;
 	}
 
-	if (events) {
-		for (i = 0; events[i]; i++)
-			free(events[i]);
-		free(events);
-	}
+	tracefs_list_free(events);
 	return failure;
 }
 
@@ -564,11 +560,7 @@ static int fill_local_events_system(const char *tracing_dir,
 	/* always succeed because parsing failures are not critical */
 	ret = 0;
 out:
-	if (systems) {
-		for (i = 0; systems[i]; i++)
-			free(systems[i]);
-		free(systems);
-	}
+	tracefs_list_free(systems);
 	return ret;
 }
 
diff --git a/lib/tracefs/tracefs-instance.c b/lib/tracefs/tracefs-instance.c
index 50e88534..e37d93d1 100644
--- a/lib/tracefs/tracefs-instance.c
+++ b/lib/tracefs/tracefs-instance.c
@@ -169,7 +169,7 @@ char *tracefs_instance_get_dir(struct tracefs_instance *instance)
  * Returns the name of the given @instance.
  * The returned string must *not* be freed.
  */
-char *tracefs_instance_get_name(struct tracefs_instance *instance)
+const char *tracefs_instance_get_name(struct tracefs_instance *instance)
 {
 	if (instance)
 		return instance->name;
diff --git a/tracecmd/trace-record.c b/tracecmd/trace-record.c
index 72a5c8c9..8cd44dd0 100644
--- a/tracecmd/trace-record.c
+++ b/tracecmd/trace-record.c
@@ -3861,7 +3861,7 @@ static void connect_to_agent(struct buffer_instance *instance)
 	unsigned int *ports;
 	int i, *fds = NULL;
 	bool use_fifos = false;
-	char *name;
+	const char *name;
 
 	name = tracefs_instance_get_name(instance->tracefs);
 	if (!no_fifos) {
diff --git a/utest/tracefs-utest.c b/utest/tracefs-utest.c
index 1c146576..b5296963 100644
--- a/utest/tracefs-utest.c
+++ b/utest/tracefs-utest.c
@@ -180,7 +180,7 @@ static void test_instance_file(void)
 {
 	struct tracefs_instance *instance = NULL;
 	const char *name = get_rand_str();
-	char *inst_name = NULL;
+	const char *inst_name = NULL;
 	const char *tdir;
 	char *inst_file;
 	char *inst_dir;
-- 
2.28.0