Struct mmap_allocator::mmap_allocator::MmapAllocator

pub struct MmapAllocator;

Allocator whose backend is mmap(2)

Trait Implementations

impl Clone for MmapAllocator

fn clone(&self) -> MmapAllocator

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for MmapAllocator

impl Debug for MmapAllocator

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

Formats the value using the given formatter.

impl Default for MmapAllocator

fn default() -> Self

Returns the "default value" for a type.

impl GlobalAlloc for MmapAllocator

Portability

alloc() calls mmap() with flag MAP_ANONYMOUS. Many systems support the flag, however, it is not specified in POSIX.

Safety

All functions are thread safe.

Error

Each function don't cause panic but set OS errno on error.

Note that it is not an error to deallocate pointer which is not allocated. This is the spec of munmap(2). See man 2 munmap for details.

unsafe fn alloc(&self, layout: Layout) -> *mut u8

Allocate memory as described by the given layout.

unsafe fn dealloc(&self, ptr: *mut u8, layout: Layout)

Deallocate the block of memory at the given ptr pointer with the given layout.

unsafe fn alloc_zeroed(&self, layout: Layout) -> *mut u8

Behaves like alloc, but also ensures that the contents are set to zero before being returned.

unsafe fn realloc(
    &self,
    ptr: *mut u8,
    layout: Layout,
    new_size: usize
) -> *mut u8

Shrink or grow a block of memory to the given new_size. The block is described by the given ptr pointer and layout.