On Fri, Jun 30, 2023 at 8:14 AM Ian Rogers <irogers@xxxxxxxxxx> wrote:
>
> On Thu, Jun 29, 2023 at 2:49 PM Namhyung Kim <namhyung@xxxxxxxxxx> wrote:
> >
> > On Tue, Jun 27, 2023 at 11:11 AM Ian Rogers <irogers@xxxxxxxxxx> wrote:
> > >
> > > Prefer informative messages rather than none with ABORT_ON. Document
> > > one failure mode and add an error message for another.
> > >
> > > Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
> > > ---
> > > tools/perf/util/parse-events.y | 22 ++++++++++++++--------
> > > 1 file changed, 14 insertions(+), 8 deletions(-)
> > >
> > > diff --git a/tools/perf/util/parse-events.y b/tools/perf/util/parse-events.y
> > > index 844646752462..454577f7aff6 100644
> > > --- a/tools/perf/util/parse-events.y
> > > +++ b/tools/perf/util/parse-events.y
> > > @@ -22,12 +22,6 @@
> > >
> > > void parse_events_error(YYLTYPE *loc, void *parse_state, void *scanner, char const *msg);
> > >
> > > -#define ABORT_ON(val) \
> > > -do { \
> > > - if (val) \
> > > - YYABORT; \
> > > -} while (0)
> > > -
> > > #define PE_ABORT(val) \
> > > do { \
> > > if (val == -ENOMEM) \
> > > @@ -618,7 +612,9 @@ PE_RAW opt_event_config
> > > YYNOMEM;
> > > errno = 0;
> > > num = strtoull($1 + 1, NULL, 16);
> > > - ABORT_ON(errno);
> > > + /* Given the lexer will only give [a-fA-F0-9]+ a failure here should be impossible. */
> > > + if (errno)
> > > + YYABORT;
> > > free($1);
> > > err = parse_events_add_numeric(_parse_state, list, PERF_TYPE_RAW, num, $2,
> > > /*wildcard=*/false);
> > > @@ -978,7 +974,17 @@ PE_VALUE PE_ARRAY_RANGE PE_VALUE
> > > {
> > > struct parse_events_array array;
> > >
> > > - ABORT_ON($3 < $1);
> > > + if ($3 < $1) {
> > > + struct parse_events_state *parse_state = _parse_state;
> > > + struct parse_events_error *error = parse_state->error;
> > > + char *err_str;
> > > +
> > > + if (asprintf(&err_str, "Expected '%ld' to be less-than '%ld'", $3, $1) < 0)
> >
> > Isn't it to be "greater-than or equal" ?
>
> I think the order is right. From the man page:
>
> When successful, these functions return the number of bytes printed,
> just like sprintf(3). If memory allocation wasn't possible, or some
> other error occurs, these functions will return -1, and the contents of
> strp are undefined.
>
> So here we need to catch -1 and ensure strp (&err_str) is NULL before
> passing it to parse_events_error__handle.
Oh, I meant the message not the condition in the if statement.
It seems it aborts if $3 < $1, then it expects $3 >= $1 in the
normal condition, right?
Thanks,
Namhyung
