Re: [Qemu-devel] [PATCH 2/2] tests: Enhance qmp output to cover partial visit

[Markus Armbruster]

Eric Blake <address@hidden> writes:

> Add a test that proves (at least when run under valgrind) that
> we are correctly handling allocated memory even when a visit
> is aborted in the middle for whatever other reason.
>
> See commit f24582d "qapi: fix double free in
> qmp_output_visitor_cleanup()" for a fix that was lacking
> testsuite exposure prior to this patch.
>
> Signed-off-by: Eric Blake <address@hidden>
> ---
>  tests/test-qmp-output-visitor.c | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
>
> diff --git a/tests/test-qmp-output-visitor.c b/tests/test-qmp-output-visitor.c
> index f7213d2..2368171 100644
> --- a/tests/test-qmp-output-visitor.c
> +++ b/tests/test-qmp-output-visitor.c
> @@ -254,6 +254,16 @@ static void 
> test_visitor_out_struct_errors(TestOutputVisitorData *data,
>  }
>
>
> +static void test_visitor_out_partial_visit(TestOutputVisitorData *data,
> +                                           const void *unused)
> +{
> +    /* Check that aborting mid-visit doesn't leak or double-free */
> +    visit_start_struct(data->ov, NULL, NULL, 0, &error_abort);
> +    visit_start_struct(data->ov, "nested", NULL, 0, &error_abort);
> +    visitor_reset(data);

Add a second test that additionally visits a member?  Or is visiting the
"nested" member enough?

> +}
> +
> +
>  static void test_visitor_out_list(TestOutputVisitorData *data,
>                                    const void *unused)
>  {
> @@ -817,6 +827,8 @@ int main(int argc, char **argv)
>                              &out_visitor_data, 
> test_visitor_out_struct_nested);
>      output_visitor_test_add("/visitor/output/struct-errors",
>                              &out_visitor_data, 
> test_visitor_out_struct_errors);
> +    output_visitor_test_add("/visitor/output/partial-visit",
> +                            &out_visitor_data, 
> test_visitor_out_partial_visit);
>      output_visitor_test_add("/visitor/output/list",
>                              &out_visitor_data, test_visitor_out_list);
>      output_visitor_test_add("/visitor/output/any",

Would you be willing to do the same for lists and alternates?

Speaking of alternates, visitor.h's virtual walk example covers struct
and list, but not alternate.