Struct Cap

pub struct Cap<H> { /* private fields */ }

A struct that wraps another allocator and limits the number of bytes that can be allocated.

Implementations

impl<H> Cap<H>

pub const fn new(allocator: H, limit: usize) -> Self

Create a new allocator, wrapping the supplied allocator and enforcing the specified limit.

For no limit, simply set the limit to the theoretical maximum usize::max_value().

pub fn remaining(&self) -> usize

Return the number of bytes remaining within the limit.

i.e. limit - allocated

pub fn limit(&self) -> usize

Return the limit in bytes.

pub fn set_limit(&self, limit: usize) -> Result<(), ()>

Set the limit in bytes.

For no limit, simply set the limit to the theoretical maximum usize::max_value().

This method will return Err if the specified limit is less than the number of bytes already allocated.

pub fn allocated(&self) -> usize

Return the number of bytes allocated. Always less than the limit.

Trait Implementations

impl<H: Debug> Debug for Cap<H>

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

Formats the value using the given formatter.

impl<H> GlobalAlloc for Cap<H>

where H: GlobalAlloc,

unsafe fn alloc(&self, l: 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, l: 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, old_l: Layout, new_s: 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.