Struct magic_ring_buffer::MagicRingBuffer

pub struct MagicRingBuffer { /* fields omitted */ }

A magic ring buffer (also known as virtual ring buffer, VRB, or a mirrored ring buffer).

Methods

impl MagicRingBuffer

pub fn allocate_mirrored_and_not_swappable_from_dev_shm(
    file_extension: &str,
    buffer_size_not_page_aligned: usize
) -> Result<Self, MirroredMemoryMapCreationError>

Creates a new instance.

pub fn recovery_if_using_persistent_memory(&self)

In a recovery scenario, we can potentially (a) re-read a message and (b) will lose all messages written but not committed between unread_offset and writer_offset.

pub fn write_some_data(
    &self,
    amount_we_want_to_write: usize,
    writer: impl FnOnce(&mut [u8])
)

The logic in writer must not panic; if it does, then the entire queue is effectively corrupt and irrecoverable.

pub fn single_reader_read_some_data<E, Reader: FnOnce(&mut [u8]) -> (usize, Result<(), E>)>(
    &self,
    reader: Reader
) -> Result<bool, E>

Read data, assuming a single reader is active.

This is NOT enforced.

Returns true if there is more data to read.

Trait Implementations

impl Debug for MagicRingBuffer

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

Formats the value using the given formatter.