Struct CortexMHeap

pub struct CortexMHeap { /* private fields */ }

Implementations

impl CortexMHeap

pub const fn empty() -> CortexMHeap

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 end_addr must be larger than start_addr

• The size of the heap is (end_addr as usize) - (start_addr as usize). The allocator won’t use the byte at end_addr.

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 CortexMHeap

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

Allocates memory as described by the given layout.

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

Deallocates 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

Shrinks or grows a block of memory to the given new_size in bytes. The block is described by the given ptr pointer and layout.