Struct Buffer 

pub struct Buffer { /* private fields */ }

A 4 KB-aligned, heap-allocated byte buffer suitable for O_DIRECT I/O.

Buffer owns a single contiguous allocation that is aligned to a FOUR_KB_BLOCK (4 096 bytes) — the minimum alignment required by O_DIRECT on all common block devices.

Cursor management is not handled here. Instead, FlushBuffer uses atomic fetch-and-add on its packed state word to hand out non-overlapping byte ranges to concurrent writers. This is what makes the unsafe impl Sync sound: no two threads are ever granted the same region.

Safety

Sync is manually implemented because UnsafeCell opts out of it by default. The invariant that upholds this is: all mutable access to the inner pointer is mediated by FlushBuffer, which guarantees exclusive ranges per writer.

Implementations

impl Buffer

pub fn new_aligned(size: usize) -> Self

Allocate a zeroed, FOUR_KB_BLOCK-aligned buffer of size bytes.

Panics

Panics if size is not a multiple of FOUR_KB_BLOCK, if the layout is otherwise invalid, or if the allocator returns a null pointer.

Trait Implementations

impl Debug for Buffer

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

Formats the value using the given formatter.

impl Drop for Buffer

fn drop(&mut self)

Executes the destructor for this type.

impl Send for Buffer

impl Sync for Buffer