Struct zx::MessageBuf

pub struct MessageBuf { /* private fields */ }

A buffer for receiving messages from a channel.

A MessageBuf is essentially a byte buffer and a vector of handles, but move semantics for “taking” handles requires special handling.

Note that for sending messages to a channel, the caller manages the buffers, using a plain byte slice and Vec<Handle>.

Implementations

impl MessageBuf

pub fn new() -> Self

Create a new, empty, message buffer.

pub fn new_with(v: Vec<u8>, h: Vec<Handle>) -> Self

Create a new non-empty message buffer.

pub fn split_mut(&mut self) -> (&mut Vec<u8>, &mut Vec<Handle>)

Splits apart the message buf into a vector of bytes and a vector of handles.

pub fn split(self) -> (Vec<u8>, Vec<Handle>)

Splits apart the message buf into a vector of bytes and a vector of handles.

pub fn ensure_capacity_bytes(&mut self, n_bytes: usize)

Ensure that the buffer has the capacity to hold at least n_bytes bytes.

pub fn ensure_capacity_handles(&mut self, n_handles: usize)

Ensure that the buffer has the capacity to hold at least n_handles handles.

pub fn ensure_initialized_bytes(&mut self, n_bytes: usize)

Ensure that at least n_bytes bytes are initialized (0 fill).

pub fn shrink_bytes_to_fit(&mut self)

Ensure that the allocation for the message’s bytes is as small as possible.

pub fn bytes(&self) -> &[u8]

Get a reference to the bytes of the message buffer, as a &[u8] slice.

pub fn n_handles(&self) -> usize

The number of handles in the message buffer. Note this counts the number available when the message was received; take_handle does not affect the count.

pub fn take_handle(&mut self, index: usize) -> Option<Handle>

Take the handle at the specified index from the message buffer. If the method is called again with the same index, it will return None, as will happen if the index exceeds the number of handles available.

pub fn clear(&mut self)

Clear the bytes and handles contained in the buf. This will drop any contained handles, resulting in their resources being freed.

Trait Implementations

impl Debug for MessageBuf

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

Formats the value using the given formatter.

impl Default for MessageBuf

fn default() -> MessageBuf

Returns the “default value” for a type.