Struct embedded_alloc::Heap

pub struct Heap { /* private fields */ }

Implementations

impl Heap

pub const fn empty() -> Heap

Crate a new UNINITIALIZED heap allocator

You must initialize this heap using the init method before using the allocator.

pub unsafe fn init(&self, start_addr: usize, size: usize)

Initializes the heap

This function must be called BEFORE you run any code that makes use of the allocator.

start_addr is the address where the heap will be located.

size is the size of the heap in bytes.

Note that:

• The heap grows “upwards”, towards larger addresses. Thus start_addr will be the smallest address used.

• The largest address used is start_addr + size - 1, so if start_addr is 0x1000 and size is 0x30000 then the allocator won’t use memory at addresses 0x31000 and larger.

Safety

Obey these or Bad Stuff will happen.

• This function must be called exactly ONCE.
• size > 0

pub fn used(&self) -> usize

Returns an estimate of the amount of bytes in use.

pub fn free(&self) -> usize

Returns an estimate of the amount of bytes available.

Trait Implementations

impl GlobalAlloc for Heap

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 in bytes. The block is described by the given ptr pointer and layout.