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

[Darren Kenny]

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 <address@hidden>

Reviewed-by: Darren Kenny <address@hidden>

> Reviewed-by: Stefan Hajnoczi <address@hidden>
> ---
> 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