Re: [Qemu-devel] [PATCH 07/12] chardev: split tcp_chr_wait_connected into two methods

[Marc-André Lureau]

Hi

On Tue, Jan 15, 2019 at 6:53 PM Daniel P. Berrangé <address@hidden> wrote:
>
> The tcp_chr_wait_connected method can deal with either server or client
> chardevs, but some callers only care about one of these possibilities.
> The tcp_chr_wait_connected method will also need some refactoring to
> reliably deal with its primary goal of allowing a device frontend to
> wait for an established connection, which will interfere with other
> callers.
>
> Split it into two methods, one responsible for server initiated
> connections, the other responsible for client initiated connections.
> In doing this split the tcp_char_connect_async() method is renamed
> to become consistent with naming of the new methods.
>
> Signed-off-by: Daniel P. Berrangé <address@hidden>
> ---
>  chardev/char-socket.c | 59 +++++++++++++++++++++++++++----------------
>  1 file changed, 37 insertions(+), 22 deletions(-)
>
> diff --git a/chardev/char-socket.c b/chardev/char-socket.c
> index 3b6ff6619b..3bd1be7631 100644
> --- a/chardev/char-socket.c
> +++ b/chardev/char-socket.c
> @@ -886,30 +886,47 @@ static void tcp_chr_accept(QIONetListener *listener,
>      tcp_chr_new_client(chr, cioc);
>  }
>
> -static int tcp_chr_wait_connected(Chardev *chr, Error **errp)
> +
> +static int tcp_chr_connect_client_sync(Chardev *chr, Error **errp)
> +{
> +    SocketChardev *s = SOCKET_CHARDEV(chr);
> +    QIOChannelSocket *sioc = qio_channel_socket_new();
> +    tcp_chr_set_client_ioc_name(chr, sioc);
> +    if (qio_channel_socket_connect_sync(sioc, s->addr, errp) < 0) {
> +        object_unref(OBJECT(sioc));
> +        return -1;
> +    }
> +    tcp_chr_new_client(chr, sioc);
> +    object_unref(OBJECT(sioc));
> +    return 0;
> +}
> +
> +
> +static void tcp_chr_accept_server_sync(Chardev *chr)
>  {
>      SocketChardev *s = SOCKET_CHARDEV(chr);
>      QIOChannelSocket *sioc;
> +    info_report("QEMU waiting for connection on: %s",
> +                chr->filename);
> +    sioc = qio_net_listener_wait_client(s->listener);
> +    tcp_chr_set_client_ioc_name(chr, sioc);
> +    tcp_chr_new_client(chr, sioc);
> +    object_unref(OBJECT(sioc));
> +}
> +
>
> +static int tcp_chr_wait_connected(Chardev *chr, Error **errp)
> +{
> +    SocketChardev *s = SOCKET_CHARDEV(chr);
>      /* It can't wait on s->connected, since it is set asynchronously
>       * in TLS and telnet cases, only wait for an accepted socket */
>      while (!s->ioc) {
>          if (s->is_listen) {
> -            info_report("QEMU waiting for connection on: %s",
> -                        chr->filename);
> -            sioc = qio_net_listener_wait_client(s->listener);
> -            tcp_chr_set_client_ioc_name(chr, sioc);
> -            tcp_chr_new_client(chr, sioc);
> -            object_unref(OBJECT(sioc));
> +            tcp_chr_accept_server_sync(chr);
>          } else {
> -            sioc = qio_channel_socket_new();
> -            tcp_chr_set_client_ioc_name(chr, sioc);
> -            if (qio_channel_socket_connect_sync(sioc, s->addr, errp) < 0) {
> -                object_unref(OBJECT(sioc));
> +            if (tcp_chr_connect_client_sync(chr, errp) < 0) {
>                  return -1;
>              }
> -            tcp_chr_new_client(chr, sioc);
> -            object_unref(OBJECT(sioc));
>          }
>      }
>
> @@ -958,7 +975,7 @@ cleanup:
>      object_unref(OBJECT(sioc));
>  }
>
> -static void tcp_chr_connect_async(Chardev *chr)
> +static void tcp_chr_connect_client_async(Chardev *chr)
>  {
>      SocketChardev *s = SOCKET_CHARDEV(chr);
>      QIOChannelSocket *sioc;
> @@ -982,7 +999,7 @@ static gboolean socket_reconnect_timeout(gpointer opaque)
>          return false;
>      }
>
> -    tcp_chr_connect_async(chr);
> +    tcp_chr_connect_client_async(chr);
>
>      return false;
>  }
> @@ -1139,7 +1156,7 @@ static void qmp_chardev_open_socket(Chardev *chr,
>      }
>
>      if (s->reconnect_time) {
> -        tcp_chr_connect_async(chr);
> +        tcp_chr_connect_client_async(chr);
>      } else {
>          if (s->is_listen) {
>              char *name;
> @@ -1159,17 +1176,15 @@ static void qmp_chardev_open_socket(Chardev *chr,
>              s->addr = socket_local_address(s->listener->sioc[0]->fd, errp);
>              update_disconnected_filename(s);
>
> -            if (is_waitconnect &&
> -                qemu_chr_wait_connected(chr, errp) < 0) {
> -                return;
> -            }
> -            if (!s->ioc) {
> +            if (is_waitconnect) {
> +                tcp_chr_accept_server_sync(chr);

Is the wait_connected() loop really unnecessary there? looks like it
is. And there is no error path either. ok

Reviewed-by: Marc-André Lureau <address@hidden>

> +            } else {
>                  qio_net_listener_set_client_func_full(s->listener,
>                                                        tcp_chr_accept,
>                                                        chr, NULL,
>                                                        chr->gcontext);
>              }
> -        } else if (qemu_chr_wait_connected(chr, errp) < 0) {
> +        } else if (tcp_chr_connect_client_sync(chr, errp) < 0) {
>              return;
>          }
>      }
> --
> 2.20.1
>