PROTOCOLS
Lifecycle
Defined in fuchsia.process.lifecycle/lifecycle.fidl
A component can implement the Lifecycle protocol to be notified of lifecycle events. It can also store some state in the framework, to be redelivered to the component the next time it is started (a practice called "escrowing").
The ELF Runner uses this protocol to communicate lifecycle changes to the component, for more details on how it uses this protocol see: https://fuchsia.dev/fuchsia-src/concepts/components/v2/elf_runner#lifecycle
OnEscrow
Escrow state shortly before the component exits.
When the ELF runner receives this event, it will arrange with the
framework to wait until the current execution of the component has
finished, then start the component again when the ZX_CHANNEL_READABLE
signal is observed on outgoing_dir
.
Repeated calls will replace the old escrowed value. This is discouraged.
Handles escrowed via OnEscrow
are always delivered to the next
execution of the component.
Response
Name | Type |
---|---|
payload |
LifecycleOnEscrowRequest
|
Stop
The process must clean up its state in preparation for termination, and
must close the channel hosting the Lifecycle
protocol when it is
ready to be terminated. The process should exit after it completes its
cleanup. At the discretion of the system the process may be terminated
before it closes the Lifecycle
channel.
Request
<EMPTY>
TABLES
LifecycleOnEscrowRequest resource
Defined in fuchsia.process.lifecycle/lifecycle.fidl
Ordinal | Field | Type | Description |
---|---|---|---|
1 |
outgoing_dir |
server_end<fuchsia.io/Directory>
|
Escrow the outgoing directory server endpoint. Whenever the
component is started again, this will be returned as the
|
2 |
escrowed_dictionary |
fuchsia.component.sandbox/DictionaryRef
|
Escrow some user defined state. Whenever the component is started
again, this will be returned as the The framework will not wait for any signals on these objects. ExampleLet's say a component needs to escrow an event pair that represents
the result of some expensive calculation. It can create a
dictionary, put the event pair inside with an appropriate key
(e.g. |