Notice connection failures, exit.

Signed-off-by: Matt Benjamin <matt@linuxbox.com>
Fix completion hook and xio_release_req.

The new workflow requires xio_msg completions to be done
in Message completion.

The xio_release_req routine unregisters memory and frees
locally-allocated xio_msg structures.

Signed-off-by: Matt Benjamin <matt@linuxbox.com>
Notice connection failures, exit.

Signed-off-by: Matt Benjamin <matt@linuxbox.com>
Remove (fixed) bug comment.

Signed-off-by: Matt Benjamin <matt@linuxbox.com>
Implement is_connected().

Signed-off-by: Matt Benjamin <matt@linuxbox.com>
Remove incorrect free in on_msg XIO_MSG_TYPE_RSP case.  Cleanups.

Signed-off-by: Matt Benjamin <matt@linuxbox.com>
Implement on_msg_error cleanup and improve disconnection handling.

Signed-off-by: Matt Benjamin <matt@linuxbox.com>