fdf_component/
context.rs

1// Copyright 2024 The Fuchsia Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5use crate::{Incoming, Node};
6use fuchsia_component::server::{ServiceFs, ServiceObjTrait};
7use log::error;
8use namespace::Namespace;
9use zx::Status;
10
11use fdf::DispatcherRef;
12use fidl_fuchsia_driver_framework::DriverStartArgs;
13
14/// The context arguments passed to the driver in its start arguments.
15pub struct DriverContext {
16    /// A reference to the root [`fdf::Dispatcher`] for this driver.
17    pub root_dispatcher: DispatcherRef<'static>,
18    /// The original [`DriverStartArgs`] passed in as start arguments, minus any parts that were
19    /// used to construct other elements of [`Self`].
20    pub start_args: DriverStartArgs,
21    /// The incoming namespace constructed from [`DriverStartArgs::incoming`]. Since producing this
22    /// consumes the incoming namespace from [`Self::start_args`], that will always be [`None`].
23    pub incoming: Incoming,
24    #[doc(hidden)]
25    _private: (),
26}
27
28impl DriverContext {
29    /// Binds the node proxy client end from the start args into a [`NodeProxy`] that can be used
30    /// to add child nodes. Dropping this proxy will result in the node being removed and the
31    /// driver starting shutdown, so it should be bound and stored in your driver object in its
32    /// [`crate::Driver::start`] method.
33    ///
34    /// After calling this, [`DriverStartArgs::node`] in [`Self::start_args`] will be `None`.
35    ///
36    /// Returns [`Status::INVALID_ARGS`] if the node client end is not present in the start
37    /// arguments.
38    pub fn take_node(&mut self) -> Result<Node, Status> {
39        let node_client = self.start_args.node.take().ok_or(Status::INVALID_ARGS)?;
40        Ok(Node::from(node_client.into_proxy()))
41    }
42
43    /// Serves the given [`ServiceFs`] on the node's outgoing directory. This can only be called
44    /// once, and after this the [`DriverStartArgs::outgoing_dir`] member will be [`None`].
45    ///
46    /// Logs an error and returns [`Status::INVALID_ARGS`] if the outgoing directory server end is
47    /// not present in the start arguments, or [`Status::INTERNAL`] if serving the connection
48    /// failed.
49    pub fn serve_outgoing<O: ServiceObjTrait>(
50        &mut self,
51        outgoing_fs: &mut ServiceFs<O>,
52    ) -> Result<(), Status> {
53        let Some(outgoing_dir) = self.start_args.outgoing_dir.take() else {
54            error!("Tried to serve on outgoing directory but it wasn't available");
55            return Err(Status::INVALID_ARGS);
56        };
57        outgoing_fs.serve_connection(outgoing_dir).map_err(|err| {
58            error!("Failed to serve outgoing directory: {err}");
59            Status::INTERNAL
60        })?;
61
62        Ok(())
63    }
64
65    pub(crate) fn new(
66        root_dispatcher: DispatcherRef<'static>,
67        mut start_args: DriverStartArgs,
68    ) -> Result<Self, Status> {
69        let incoming_namespace: Namespace = start_args
70            .incoming
71            .take()
72            .unwrap_or_else(|| vec![])
73            .try_into()
74            .map_err(|_| Status::INVALID_ARGS)?;
75        let incoming = incoming_namespace.try_into().map_err(|_| Status::INVALID_ARGS)?;
76        Ok(DriverContext { root_dispatcher, start_args, incoming, _private: () })
77    }
78
79    pub(crate) fn start_logging(&self, driver_name: &str) -> Result<(), Status> {
80        let log_proxy = match self.incoming.protocol().connect() {
81            Ok(log_proxy) => log_proxy,
82            Err(err) => {
83                eprintln!("Error connecting to log sink proxy at driver startup: {err}. Continuing without logging.");
84                return Ok(());
85            }
86        };
87
88        if let Err(e) = diagnostics_log::initialize(
89            diagnostics_log::PublishOptions::default()
90                .use_log_sink(log_proxy)
91                .tags(&["driver", driver_name]),
92        ) {
93            eprintln!("Error initializing logging at driver startup: {e}");
94        }
95        Ok(())
96    }
97}
fdf_component/context.rs

fdf_component/
context.rs
