Re: [PATCH v8 05/21] libqtest: add a layer of abstraction to send/recv

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

On Wed, Jan 29, 2020 at 05:34:15AM +0000, Bulekov, Alexander wrote:
>This makes it simple to swap the transport functions for qtest commands
>to and from the qtest client. For example, now it is possible to
>directly pass qtest commands to a server handler that exists within the
>same process, without the standard way of writing to a file descriptor.
>
>Signed-off-by: Alexander Bulekov <alxndr@bu.edu>

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

>Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
>---
> tests/qtest/libqtest.c | 48 ++++++++++++++++++++++++++++++++++--------
> 1 file changed, 39 insertions(+), 9 deletions(-)
>
>diff --git a/tests/qtest/libqtest.c b/tests/qtest/libqtest.c
>index 76c9f8eade..e5056a1d0f 100644
>--- a/tests/qtest/libqtest.c
>+++ b/tests/qtest/libqtest.c
>@@ -35,6 +35,15 @@
> #define SOCKET_TIMEOUT 50
> #define SOCKET_MAX_FDS 16
>
>+
>+typedef void (*QTestSendFn)(QTestState *s, const char *buf);
>+typedef GString* (*QTestRecvFn)(QTestState *);
>+
>+typedef struct QTestClientTransportOps {
>+    QTestSendFn     send;      /* for sending qtest commands */
>+    QTestRecvFn     recv_line; /* for receiving qtest command responses */
>+} QTestTransportOps;
>+
> struct QTestState
> {
>     int fd;
>@@ -45,6 +54,7 @@ struct QTestState
>     bool big_endian;
>     bool irq_level[MAX_IRQ];
>     GString *rx;
>+    QTestTransportOps ops;
> };
>
> static GHookList abrt_hooks;
>@@ -52,6 +62,14 @@ static struct sigaction sigact_old;
>
> static int qtest_query_target_endianness(QTestState *s);
>
>+static void qtest_client_socket_send(QTestState*, const char *buf);
>+static void socket_send(int fd, const char *buf, size_t size);
>+
>+static GString *qtest_client_socket_recv_line(QTestState *);
>+
>+static void qtest_client_set_tx_handler(QTestState *s, QTestSendFn send);
>+static void qtest_client_set_rx_handler(QTestState *s, QTestRecvFn recv);
>+
> static int init_socket(const char *socket_path)
> {
>     struct sockaddr_un addr;
>@@ -234,6 +252,9 @@ QTestState *qtest_init_without_qmp_handshake(const char *extra_args)
>     sock = init_socket(socket_path);
>     qmpsock = init_socket(qmp_socket_path);
>
>+    qtest_client_set_rx_handler(s, qtest_client_socket_recv_line);
>+    qtest_client_set_tx_handler(s, qtest_client_socket_send);
>+
>     qtest_add_abrt_handler(kill_qemu_hook_func, s);
>
>     command = g_strdup_printf("exec %s "
>@@ -379,13 +400,9 @@ static void socket_send(int fd, const char *buf, size_t size)
>     }
> }
>
>-static void socket_sendf(int fd, const char *fmt, va_list ap)
>+static void qtest_client_socket_send(QTestState *s, const char *buf)
> {
>-    gchar *str = g_strdup_vprintf(fmt, ap);
>-    size_t size = strlen(str);
>-
>-    socket_send(fd, str, size);
>-    g_free(str);
>+    socket_send(s->fd, buf, strlen(buf));
> }
>
> static void GCC_FMT_ATTR(2, 3) qtest_sendf(QTestState *s, const char *fmt, ...)
>@@ -393,8 +410,11 @@ static void GCC_FMT_ATTR(2, 3) qtest_sendf(QTestState *s, const char *fmt, ...)
>     va_list ap;
>
>     va_start(ap, fmt);
>-    socket_sendf(s->fd, fmt, ap);
>+    gchar *str = g_strdup_vprintf(fmt, ap);
>     va_end(ap);
>+
>+    s->ops.send(s, str);
>+    g_free(str);
> }
>
> /* Sends a message and file descriptors to the socket.
>@@ -431,7 +451,7 @@ static void socket_send_fds(int socket_fd, int *fds, size_t fds_num,
>     g_assert_cmpint(ret, >, 0);
> }
>
>-static GString *qtest_recv_line(QTestState *s)
>+static GString *qtest_client_socket_recv_line(QTestState *s)
> {
>     GString *line;
>     size_t offset;
>@@ -468,7 +488,7 @@ static gchar **qtest_rsp(QTestState *s, int expected_args)
>     int i;
>
> redo:
>-    line = qtest_recv_line(s);
>+    line = s->ops.recv_line(s);
>     words = g_strsplit(line->str, " ", 0);
>     g_string_free(line, TRUE);
>
>@@ -1337,3 +1357,13 @@ void qmp_assert_error_class(QDict *rsp, const char *class)
>
>     qobject_unref(rsp);
> }
>+
>+static void qtest_client_set_tx_handler(QTestState *s,
>+                    QTestSendFn send)
>+{
>+    s->ops.send = send;
>+}
>+static void qtest_client_set_rx_handler(QTestState *s, QTestRecvFn recv)
>+{
>+    s->ops.recv_line = recv;
>+}
>-- 
>2.23.0
>
>