Struct fuchsia_zircon::Channel

pub struct Channel(/* private fields */);

An object representing a Zircon channel.

As essentially a subtype of Handle, it can be freely interconverted.

Implementations

impl Channel

pub fn create() -> (Self, Self)

Create a channel, resulting in a pair of Channel objects representing both sides of the channel. Messages written into one may be read from the opposite.

Wraps the zx_channel_create syscall.

Panics

If the process’ job policy denies channel creation or the kernel reports no memory available to create a new channel.

pub fn read_raw( &self, bytes: &mut [u8], handles: &mut [MaybeUninit<Handle>] ) -> Result<(Result<(), Status>, usize, usize), (usize, usize)>

Read a message from a channel. Wraps the zx_channel_read syscall.

If the slice lacks the capacity to hold the pending message, returns an Err with the number of bytes and number of handles needed. Otherwise returns an Ok with the result as usual. If both the outer and inner Results are Ok, then the caller can assume that the handles array is initialized.

Note that read_slice may call read_raw with some uninitialized elements because it resizes the input vector to its capacity without initializing all of the elements.

pub fn read(&self, buf: &mut MessageBuf) -> Result<(), Status>

Read a message from a channel.

Note that this method can cause internal reallocations in the MessageBuf if it is lacks capacity to hold the full message. If such reallocations are not desirable, use read_raw instead.

pub fn read_split( &self, bytes: &mut Vec<u8>, handles: &mut Vec<Handle> ) -> Result<(), Status>

Read a message from a channel into a separate byte vector and handle vector.

Note that this method can cause internal reallocations in the Vecs if they lacks capacity to hold the full message. If such reallocations are not desirable, use read_raw instead.

pub fn read_etc_raw( &self, bytes: &mut [u8], handle_infos: &mut [MaybeUninit<HandleInfo>] ) -> Result<(Result<(), Status>, usize, usize), (usize, usize)>

Read a message from a channel. Wraps the zx_channel_read_etc syscall.

This differs from read_raw in that it returns extended information on the handles.

If the slice lacks the capacity to hold the pending message, returns an Err with the number of bytes and number of handles needed. Otherwise returns an Ok with the result as usual. If both the outer and inner Results are Ok, then the caller can assume that the handle_infos array is initialized.

Note that read_etc_slice may call read_etc_raw with some uninitialized elements because it resizes the input vector to its capacity without initializing all of the elements.

pub fn read_etc(&self, buf: &mut MessageBufEtc) -> Result<(), Status>

Read a message from a channel.

This differs from read in that it returns extended information on the handles.

Note that this method can cause internal reallocations in the MessageBufEtc if it is lacks capacity to hold the full message. If such reallocations are not desirable, use read_etc_raw instead.

pub fn read_etc_split( &self, bytes: &mut Vec<u8>, handle_infos: &mut Vec<HandleInfo> ) -> Result<(), Status>

Read a message from a channel into a separate byte vector and handle vector.

This differs from read_split in that it returns extended information on the handles.

Note that this method can cause internal reallocations in the Vecs if they lacks capacity to hold the full message. If such reallocations are not desirable, use read_raw instead.

pub fn write(&self, bytes: &[u8], handles: &mut [Handle]) -> Result<(), Status>

Write a message to a channel. Wraps the zx_channel_write syscall.

pub fn write_etc( &self, bytes: &[u8], handle_dispositions: &mut [HandleDisposition<'_>] ) -> Result<(), Status>

Write a message to a channel. Wraps the zx_channel_write_etc syscall.

pub fn call( &self, timeout: Time, bytes: &[u8], handles: &mut [Handle], buf: &mut MessageBuf ) -> Result<(), Status>

Send a message consisting of the given bytes and handles to a channel and await a reply.

The first four bytes of the written and read back messages are treated as a transaction ID of type zx_txid_t. The kernel generates a txid for the written message, replacing that part of the message as read from userspace. In other words, the first four bytes of bytes will be ignored, and the first four bytes of the response will contain a kernel-generated txid.

Wraps the zx_channel_call syscall.

Note that unlike read, the caller must ensure that the MessageBuf has enough capacity for the bytes and handles which will be received, as replies which are too large are discarded.

On failure returns the both the main and read status.

pub fn call_etc( &self, timeout: Time, bytes: &[u8], handle_dispositions: &mut [HandleDisposition<'_>], buf: &mut MessageBufEtc ) -> Result<(), Status>

Send a message consisting of the given bytes and handles to a channel and await a reply.

The first four bytes of the written and read back messages are treated as a transaction ID of type zx_txid_t. The kernel generates a txid for the written message, replacing that part of the message as read from userspace. In other words, the first four bytes of bytes will be ignored, and the first four bytes of the response will contain a kernel-generated txid.

This differs from call, in that it uses extended handle info.

Wraps the zx_channel_call_etc syscall.

Note that unlike read_etc, the caller must ensure that the MessageBufEtc has enough capacity for the bytes and handles which will be received, as replies which are too large are discarded.

On failure returns the both the main and read status.

Trait Implementations

impl AsHandleRef for Channel

fn as_handle_ref(&self) -> HandleRef<'_>

Get a reference to the handle. One important use of such a reference is for object_wait_many.

fn raw_handle(&self) -> zx_handle_t

Interpret the reference as a raw handle (an integer type). Two distinct handles will have different raw values (so it can perhaps be used as a key in a data structure).

fn signal_handle( &self, clear_mask: Signals, set_mask: Signals ) -> Result<(), Status>

Set and clear userspace-accessible signal bits on an object. Wraps the zx_object_signal syscall.

fn wait_handle( &self, signals: Signals, deadline: Time ) -> Result<Signals, Status>

Waits on a handle. Wraps the zx_object_wait_one syscall.

fn wait_async_handle( &self, port: &Port, key: u64, signals: Signals, options: WaitAsyncOpts ) -> Result<(), Status>

Causes packet delivery on the given port when the object changes state and matches signals. zx_object_wait_async syscall.

fn get_name(&self) -> Result<CString, Status>

Get the Property::NAME property for this object.

fn set_name(&self, name: &CStr) -> Result<(), Status>

Set the Property::NAME property for this object.

fn basic_info(&self) -> Result<HandleBasicInfo, Status>

Wraps the zx_object_get_info syscall for the ZX_INFO_HANDLE_BASIC topic.

fn count_info(&self) -> Result<HandleCountInfo, Status>

Wraps the zx_object_get_info syscall for the ZX_INFO_HANDLE_COUNT topic.

fn get_koid(&self) -> Result<Koid, Status>

Returns the koid (kernel object ID) for this handle.

impl AsRef<Channel> for Channel

fn as_ref(&self) -> &Self

Converts this type into a shared reference of the (usually inferred) input type.

impl Debug for Channel

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

Formats the value using the given formatter.

impl From<Channel> for Handle

fn from(x: Channel) -> Handle

Converts to this type from the input type.

impl From<Handle> for Channel

fn from(handle: Handle) -> Self

Converts to this type from the input type.

impl HandleBased for Channel

fn duplicate_handle(&self, rights: Rights) -> Result<Self, Status>

Duplicate a handle, possibly reducing the rights available. Wraps the zx_handle_duplicate syscall.

fn replace_handle(self, rights: Rights) -> Result<Self, Status>

Create a replacement for a handle, possibly reducing the rights available. This invalidates the original handle. Wraps the zx_handle_replace syscall.

fn into_handle(self) -> Handle

Converts the value into its inner handle.

fn into_raw(self) -> zx_handle_t

Converts the handle into it’s raw representation.

fn from_handle(handle: Handle) -> Self

Creates an instance of this type from a handle.

fn into_handle_based<H: HandleBased>(self) -> H

Creates an instance of another handle-based type from this value’s inner handle.

fn from_handle_based<H: HandleBased>(h: H) -> Self

Creates an instance of this type from the inner handle of another handle-based type.

fn is_invalid_handle(&self) -> bool

impl Hash for Channel

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for Channel

fn cmp(&self, other: &Channel) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized + PartialOrd,

Restrict a value to a certain interval.

impl PartialEq for Channel

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

This method tests for self and other values to be equal, and is used by ==.

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

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

impl PartialOrd for Channel

fn partial_cmp(&self, other: &Channel) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

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

This method tests less than (for self and other) and is used by the < operator.

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

This method tests less than or equal to (for self and other) and is used by the <= operator.

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

This method tests greater than (for self and other) and is used by the > operator.

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

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl Peered for Channel

fn signal_peer( &self, clear_mask: Signals, set_mask: Signals ) -> Result<(), Status>

Set and clear userspace-accessible signal bits on the object’s peer. Wraps the zx_object_signal_peer syscall.

impl Eq for Channel

impl StructuralPartialEq for Channel