Eric Blake <ebl...@redhat.com> writes:
> On 08/08/2018 07:02 AM, Markus Armbruster wrote:
>> To permit recovering from arbitrary JSON parse errors, the JSON parser
>> resets itself on lexical errors. We recommend sending a 0xff byte for
>> that purpose, and test-qga covers this usage since commit 5229564b832.
>> That commit had to add an ugly hack to qmp_fd_vsend() to make capable
>> of sending this byte (it's designed to send only valid JSON).
>>
>> The previous commit added a way to send arbitrary text. Put that to
>> use for this purpose, and drop the hack from qmp_fd_vsend().
>>
>> Signed-off-by: Markus Armbruster <arm...@redhat.com>
>> ---
>> tests/libqtest.c | 39 +++++++++++++++++++++------------------
>> tests/libqtest.h | 2 ++
>> tests/test-qga.c | 8 ++++----
>> 3 files changed, 27 insertions(+), 22 deletions(-)
>>
>> diff --git a/tests/libqtest.c b/tests/libqtest.c
>> index c02fc91b37..9c844874e4 100644
>> --- a/tests/libqtest.c
>> +++ b/tests/libqtest.c
>> @@ -489,16 +489,6 @@ void qmp_fd_vsend(int fd, const char *fmt, va_list ap)
>> {
>> QObject *qobj;
>> - /*
>> - * qobject_from_vjsonf_nofail() chokes on leading 0xff as invalid
>> - * JSON, but tests/test-qga.c needs to send that to test QGA
>> - * synchronization
>> - */
>> - if (*fmt == '\377') {
>> - socket_send(fd, fmt, 1);
>> - fmt++;
>> - }
>> -
>> /* Going through qobject ensures we escape strings properly */
>> qobj = qobject_from_vjsonf_nofail(fmt, ap);
>
> This does JSON interpolation...
>
>> @@ -586,23 +576,36 @@ void qtest_qmp_send(QTestState *s, const
>> char *fmt, ...)
>> va_end(ap);
>> }
>> -void qtest_qmp_send_raw(QTestState *s, const char *fmt, ...)
>> +void qmp_fd_vsend_raw(int fd, const char *fmt, va_list ap)
>> {
>> bool log = getenv("QTEST_LOG") != NULL;
>> - va_list ap;
>> - char *str;
>> -
>> - va_start(ap, fmt);
>> - str = g_strdup_vprintf(fmt, ap);
>> - va_end(ap);
>> + char *str = g_strdup_vprintf(fmt, ap);
>
> ...while the new code does printf interpolation...
>
>> +++ b/tests/test-qga.c
>> @@ -147,10 +147,10 @@ static void test_qga_sync_delimited(gconstpointer fix)
>> unsigned char c;
>> QDict *ret;
>> - qmp_fd_send(fixture->fd,
>> - "\xff{'execute': 'guest-sync-delimited',"
>> - " 'arguments': {'id': %u } }",
>> - r);
>> + qmp_fd_send_raw(fixture->fd,
>> + "\xff{'execute': 'guest-sync-delimited',"
>> + " 'arguments': {'id': %u } }",
>> + r);
>
> ...and your test was relying on interpolation. Fortunately, your only
Yes, my patch is a bit lazy there.
> thing being interpolated (%u) happens to result in valid JSON - but
> you may want to split this into:
>
> qmp_fd_send_raw(fixture->fd, "\xff");
> qmp_fd_send(fixutre->fd, "{'execute ... %u}}", f);
>
> to make it less questionable. If not, then call it out in the commit
> message and/or a comment on the code itself.
Splitting is easier than explaining, so that's what I'll do.
