def load(self, yamlfp: BinaryIO) -> None:
"""Load a YaML configuration stream.
:param yamlfp: YaML stream to be parsed
"""
backend = get_backend()
with yamlfp:
try:
for ydef in YAML().load_all(yamlfp):
self._build_root(backend, ydef)
except Exception as exc:
raise ValueError(f'Invalid configuration: {exc}') from exc
self._validate()
UsbTools.release_all_devices(VirtDevice)
UsbTools.flush_cache()
def unload(self) -> None:
"""Unload current USB topology, release all allocated devices, and
flush UsbTools cache.
Note that the application should also flush UsbTools cache,
or reference to 'disconnected' devices may persist.
"""
backend = get_backend()
backend.flush_devices()
count = UsbTools.release_all_devices(VirtDevice)
UsbTools.flush_cache()
return count
