Re: [PATCH perf/core v2 6/8] perf pmu: Make pmu_formats_string to check return value of strbuf

[Arnaldo Carvalho de Melo <acme@kernel.org>]

Em Sat, Apr 30, 2016 at 12:10:42AM +0900, Masami Hiramatsu escreveu:
> Make pmu_formats_string() to check return value of
> strbuf APIs so that it can detect errors in it.
> 
> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
> ---
>  tools/perf/util/pmu.c |   10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
> index bf34468..ddb0261 100644
> --- a/tools/perf/util/pmu.c
> +++ b/tools/perf/util/pmu.c
> @@ -643,20 +643,20 @@ static int pmu_resolve_param_term(struct parse_events_term *term,
>  static char *pmu_formats_string(struct list_head *formats)
>  {
>  	struct perf_pmu_format *format;
> -	char *str;
> -	struct strbuf buf;
> +	char *str = NULL;
> +	struct strbuf buf = STRBUF_INIT;
>  	unsigned i = 0;

Ok, here you use STRBUF_INIT and you removed the equivalent (I guess)
call to strbuf_init(&buf, 0) below, i.e. there will be no alloc the
check.

Looks ok.
  
>  	if (!formats)
>  		return NULL;
>  
> -	strbuf_init(&buf, 0);
>  	/* sysfs exported terms */
>  	list_for_each_entry(format, formats, list)
> -		strbuf_addf(&buf, i++ ? ",%s" : "%s",
> -			    format->name);
> +		if (strbuf_addf(&buf, i++ ? ",%s" : "%s", format->name) < 0)
> +			goto error;
>  
>  	str = strbuf_detach(&buf, NULL);
> +error:
>  	strbuf_release(&buf);
>  
>  	return str;