Re: [PATCH v8 06/21] libqtest: make bufwrite rely on the TransportOps

[Darren Kenny <darren.kenny@oracle.com>]

On Wed, Jan 29, 2020 at 05:34:16AM +0000, Bulekov, Alexander wrote:
>When using qtest "in-process" communication, qtest_sendf directly calls
>a function in the server (qtest.c). Previously, bufwrite used
>socket_send, which bypasses the TransportOps enabling the call into
>qtest.c. This change replaces the socket_send calls with ops->send,
>maintaining the benefits of the direct socket_send call, while adding
>support for in-process qtest calls.
>
>Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
>Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>

Reviewed-by: Darren Kenny <darren.kenny@oracle.com>

>---
> tests/qtest/libqtest.c | 71 ++++++++++++++++++++++++++++++++++++++++--
> tests/qtest/libqtest.h |  4 +++
> 2 files changed, 73 insertions(+), 2 deletions(-)
>
>diff --git a/tests/qtest/libqtest.c b/tests/qtest/libqtest.c
>index e5056a1d0f..49075b55a1 100644
>--- a/tests/qtest/libqtest.c
>+++ b/tests/qtest/libqtest.c
>@@ -37,10 +37,18 @@
>
>
> typedef void (*QTestSendFn)(QTestState *s, const char *buf);
>+typedef void (*ExternalSendFn)(void *s, const char *buf);
> typedef GString* (*QTestRecvFn)(QTestState *);
>
> typedef struct QTestClientTransportOps {
>     QTestSendFn     send;      /* for sending qtest commands */
>+
>+    /*
>+     * use external_send to send qtest command strings through functions which
>+     * do not accept a QTestState as the first parameter.
>+     */
>+    ExternalSendFn  external_send;
>+
>     QTestRecvFn     recv_line; /* for receiving qtest command responses */
> } QTestTransportOps;
>
>@@ -1078,8 +1086,8 @@ void qtest_bufwrite(QTestState *s, uint64_t addr, const void *data, size_t size)
>
>     bdata = g_base64_encode(data, size);
>     qtest_sendf(s, "b64write 0x%" PRIx64 " 0x%zx ", addr, size);
>-    socket_send(s->fd, bdata, strlen(bdata));
>-    socket_send(s->fd, "\n", 1);
>+    s->ops.send(s, bdata);
>+    s->ops.send(s, "\n");
>     qtest_rsp(s, 0);
>     g_free(bdata);
> }
>@@ -1367,3 +1375,62 @@ static void qtest_client_set_rx_handler(QTestState *s, QTestRecvFn recv)
> {
>     s->ops.recv_line = recv;
> }
>+/* A type-safe wrapper for s->send() */
>+static void send_wrapper(QTestState *s, const char *buf)
>+{
>+    s->ops.external_send(s, buf);
>+}
>+
>+static GString *qtest_client_inproc_recv_line(QTestState *s)
>+{
>+    GString *line;
>+    size_t offset;
>+    char *eol;
>+
>+    eol = strchr(s->rx->str, '\n');
>+    offset = eol - s->rx->str;
>+    line = g_string_new_len(s->rx->str, offset);
>+    g_string_erase(s->rx, 0, offset + 1);
>+    return line;
>+}
>+
>+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);
>+
>+    /*
>+     * Set a dummy path for QTEST_QEMU_BINARY. Doesn't need to exist, but this
>+     * way, qtest_get_arch works for inproc qtest.
>+     */
>+    gchar *bin_path = g_strconcat("/qemu-system-", arch, NULL);
>+    setenv("QTEST_QEMU_BINARY", bin_path, 0);
>+    g_free(bin_path);
>+
>+    return qts;
>+}
>+
>+void qtest_client_inproc_recv(void *opaque, const char *str)
>+{
>+    QTestState *qts = *(QTestState **)opaque;
>+
>+    if (!qts->rx) {
>+        qts->rx = g_string_new(NULL);
>+    }
>+    g_string_append(qts->rx, str);
>+    return;
>+}
>diff --git a/tests/qtest/libqtest.h b/tests/qtest/libqtest.h
>index c9e21e05b3..f5cf93c386 100644
>--- a/tests/qtest/libqtest.h
>+++ b/tests/qtest/libqtest.h
>@@ -729,4 +729,8 @@ bool qtest_probe_child(QTestState *s);
>  */
> void qtest_set_expected_status(QTestState *s, int status);
>
>+QTestState *qtest_inproc_init(QTestState **s, bool log, const char* arch,
>+                    void (*send)(void*, const char*));
>+
>+void qtest_client_inproc_recv(void *opaque, const char *str);
> #endif
>-- 
>2.23.0
>
>