Re: [PATCH v6 12/21] libqtest: add in-process qtest.c tx/rx handlers

[Alexander Bulekov]

On 200103 1115, Stefan Hajnoczi wrote:
> On Fri, Nov 29, 2019 at 09:34:47PM +0000, Oleinik, Alexander wrote:
> > +QTestState *qtest_inproc_init(QTestState **s, bool log, const char* arch,
> > +                    void (*send)(void*, const char*))
> > +{
> > +    QTestState *qts;
> > +    qts = g_new0(QTestState, 1);
> > +    *s = qts; /* Expose qts early on, since the query endianness relies on 
> > it */
> > +    qts->wstatus = 0;
> > +    for (int i = 0; i < MAX_IRQ; i++) {
> > +        qts->irq_level[i] = false;
> > +    }
> > +
> > +    qtest_client_set_rx_handler(qts, qtest_client_inproc_recv_line);
> > +
> > +    /* send() may not have a matching protoype, so use a type-safe wrapper 
> > */
> > +    qts->ops.external_send = send;
> > +    qtest_client_set_tx_handler(qts, send_wrapper);
> > +
> > +    qts->big_endian = qtest_query_target_endianness(qts);
> > +    gchar *bin_path = g_strconcat("/qemu-system-", arch, NULL);
> > +    setenv("QTEST_QEMU_BINARY", bin_path, 0);
> > +    g_free(bin_path);
> 
> Is this a dummy path that is needed to make other code happy?  Or does
> the user need to have an actual file at /qemu-system-ARCH?

Yes - with the inproc mode this is only needed to make qtest_get_arch
happy, which simply returns the suffix of the env variable. Standard
qtest initialization relies on it in qtest_init_without_qmp_handshake,
but that function is not used by the fuzzer.