Re: [PATCH 09/11] tools lib traceevent: Add alias field to struct format_field

[Steven Rostedt <rostedt@goodmis.org>]

On Fri, Feb 20, 2015 at 11:17:06PM +0100, Jiri Olsa wrote:
> ---
>  tools/lib/traceevent/event-parse.c | 1 +
>  tools/lib/traceevent/event-parse.h | 1 +
>  2 files changed, 2 insertions(+)
> 
> diff --git a/tools/lib/traceevent/event-parse.c b/tools/lib/traceevent/event-parse.c
> index afe20ed9fac8..b35664cc1edc 100644
> --- a/tools/lib/traceevent/event-parse.c
> +++ b/tools/lib/traceevent/event-parse.c
> @@ -6236,6 +6236,7 @@ static void free_format_fields(struct format_field *field)
>  		next = field->next;
>  		free(field->type);
>  		free(field->name);
> +		free(field->alias);

Hmm, didn't we say that if there's no need for the alias that the alias will
simply be a pointer to name? If that's the case we need:

	if (field->alias != field->name)
		free(field->alias);
	free(field->name);

Otherwise it will be a double free.

-- Steve

>  		free(field);
>  		field = next;
>  	}
> diff --git a/tools/lib/traceevent/event-parse.h b/tools/lib/traceevent/event-parse.h
> index 5b4efc062320..8490a4afffa2 100644
> --- a/tools/lib/traceevent/event-parse.h
> +++ b/tools/lib/traceevent/event-parse.h
> @@ -187,6 +187,7 @@ struct format_field {
>  	struct event_format	*event;
>  	char			*type;
>  	char			*name;
> +	char			*alias;
>  	int			offset;
>  	int			size;