Struct ComponentStartInfo

pub struct ComponentStartInfo {
    pub resolved_url: Option<String>,
    pub program: Option<Dictionary>,
    pub ns: Option<Vec<ComponentNamespaceEntry>>,
    pub outgoing_dir: Option<ServerEnd<DirectoryMarker>>,
    pub runtime_dir: Option<ServerEnd<DirectoryMarker>>,
    pub numbered_handles: Option<Vec<HandleInfo>>,
    pub encoded_config: Option<Data>,
    pub break_on_start: Option<EventPair>,
    pub component_instance: Option<Event>,
    pub escrowed_dictionary: Option<DictionaryRef>,
    /* private fields */
}

Parameters for starting a new component instance.

Fields

resolved_url: Option<String>

The resolved URL of the component.

This is the canonical URL obtained by the component resolver after following redirects and resolving relative paths.

program: Option<Dictionary>

The component’s program declaration. This information originates from ComponentDecl.program.

ns: Option<Vec<ComponentNamespaceEntry>>

The namespace to provide to the component instance.

A namespace specifies the set of directories that a component instance receives at start-up. Through the namespace directories, a component may access capabilities available to it. The contents of the namespace are mainly determined by the component’s use declarations but may also contain additional capabilities automatically provided by the framework.

By convention, a component’s namespace typically contains some or all of the following directories:

• “/svc”: A directory containing services that the component requested to use via its “import” declarations.
• “/pkg”: A directory containing the component’s package, including its binaries, libraries, and other assets.

The mount points specified in each entry must be unique and non-overlapping. For example, [{“/foo”, ..}, {“/foo/bar”, ..}] is invalid.

outgoing_dir: Option<ServerEnd<DirectoryMarker>>

The directory this component serves.

runtime_dir: Option<ServerEnd<DirectoryMarker>>

The directory served by the runner to present runtime information about the component. The runner must either serve it, or drop it to avoid blocking any consumers indefinitely.

numbered_handles: Option<Vec<HandleInfo>>

The numbered handles that were passed to the component.

If the component does not support numbered handles, the runner is expected to close the handles.

encoded_config: Option<Data>

Binary representation of the component’s configuration.

Layout

The first 2 bytes of the data should be interpreted as an unsigned 16-bit little-endian integer which denotes the number of bytes following it that contain the configuration checksum. After the checksum, all the remaining bytes are a persistent FIDL message of a top-level struct. The struct’s fields match the configuration fields of the component’s compiled manifest in the same order.

break_on_start: Option<EventPair>

An eventpair that debuggers can use to defer the launch of the component.

For example, ELF runners hold off from creating processes in the component until ZX_EVENTPAIR_PEER_CLOSED is signaled on this eventpair. They also ensure that runtime_dir is served before waiting on this eventpair. ELF debuggers can query the runtime_dir to decide whether to attach before they drop the other side of the eventpair, which is sent in the payload of the DebugStarted event in fuchsia.component.events.

component_instance: Option<Event>

An opaque token that represents the component instance.

The fuchsia.component/Introspector protocol may be used to get the string moniker of the instance from this token.

Runners may publish this token as part of diagnostics information, to identify the running component without knowing its moniker.

The token is invalidated when the component instance is destroyed.

escrowed_dictionary: Option<DictionaryRef>

A dictionary containing data and handles that the component has escrowed during its previous execution via [ComponentController.OnEscrow].

Trait Implementations

impl Debug for ComponentStartInfo

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Decode<ComponentStartInfo, DefaultFuchsiaResourceDialect> for ComponentStartInfo

fn new_empty() -> Self

Creates a valid instance of Self. The specific value does not matter, since it will be overwritten by decode.

unsafe fn decode( &mut self, decoder: &mut Decoder<'_, DefaultFuchsiaResourceDialect>, offset: usize, depth: Depth, ) -> Result<()>

Decodes an object of type T from the decoder’s buffers into self.

impl Default for ComponentStartInfo

fn default() -> ComponentStartInfo

Returns the “default value” for a type.

impl Encode<ComponentStartInfo, DefaultFuchsiaResourceDialect> for &mut ComponentStartInfo

unsafe fn encode( self, encoder: &mut Encoder<'_, DefaultFuchsiaResourceDialect>, offset: usize, depth: Depth, ) -> Result<()>

Encodes the object into the encoder’s buffers. Any handles stored in the object are swapped for Handle::INVALID.

impl PartialEq for ComponentStartInfo

fn eq(&self, other: &ComponentStartInfo) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl ResourceTypeMarker for ComponentStartInfo

type Borrowed<'a> = &'a mut ComponentStartInfo

The Rust type to use for encoding. This is a particular Encode<Self> type cheaply obtainable from &mut Self::Owned. There are three cases:

fn take_or_borrow<'a>( value: &'a mut <Self as TypeMarker>::Owned, ) -> Self::Borrowed<'a>

Cheaply converts from &mut Self::Owned to Self::Borrowed. For HandleBased types this is “take” (it returns an owned handle and replaces value with Handle::invalid), and for all other types it is “borrow” (just converts from one reference to another).

impl TypeMarker for ComponentStartInfo

type Owned = ComponentStartInfo

The owned Rust type which this FIDL type decodes into.

fn inline_align(_context: Context) -> usize

Returns the minimum required alignment of the inline portion of the encoded object. It must be a (nonzero) power of two.

fn inline_size(_context: Context) -> usize

Returns the size of the inline portion of the encoded object, including padding for alignment. Must be a multiple of inline_align.

fn encode_is_copy() -> bool

Returns true if the memory layout of Self::Owned matches the FIDL wire format and encoding requires no validation. When true, we can optimize encoding arrays and vectors of Self::Owned to a single memcpy.

fn decode_is_copy() -> bool

Returns true if the memory layout of Self::Owned matches the FIDL wire format and decoding requires no validation. When true, we can optimize decoding arrays and vectors of Self::Owned to a single memcpy.

impl Standalone<DefaultFuchsiaResourceDialect> for ComponentStartInfo

impl StructuralPartialEq for ComponentStartInfo