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

[Steven Rostedt <rostedt@goodmis.org>]

On Thu, 12 Nov 2020 11:11:05 +0200
"Tzvetomir Stoyanov (VMware)" <tz.stoyanov@gmail.com> wrote:

> 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@gmail.com>
> ---
>  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;
>  }
>  

The above looks like it belongs in its own patch (not related to this
change).

-- Steve