Struct Memory

pub struct Memory(/* private fields */);

A Wasm linear memory reference.

Implementations

impl Memory

pub fn new(ctx: impl AsContextMut, ty: MemoryType) -> Result<Self, MemoryError>

Creates a new linear memory to the store.

Errors

If more than u32::MAX much linear memory is allocated.

pub fn new_static( ctx: impl AsContextMut, ty: MemoryType, buf: &'static mut [u8], ) -> Result<Self, MemoryError>

Creates a new linear memory to the store.

Errors

If more than u32::MAX much linear memory is allocated.

• If static buffer is invalid

pub fn ty(&self, ctx: impl AsContext) -> MemoryType

Returns the memory type of the linear memory.

Panics

Panics if ctx does not own this Memory.

pub fn size(&self, ctx: impl AsContext) -> u32

Returns the size, in WebAssembly pages, of this Wasm linear memory.

Panics

Panics if ctx does not own this Memory.

pub fn grow( &self, ctx: impl AsContextMut, additional: u32, ) -> Result<u32, MemoryError>

Grows the linear memory by the given amount of new pages.

Returns the amount of pages before the operation upon success.

Errors

If the linear memory would grow beyond its maximum limit after the grow operation.

Panics

Panics if ctx does not own this Memory.

pub fn data<'a, T: 'a>(&self, ctx: impl Into<StoreContext<'a, T>>) -> &'a [u8]

Returns a shared slice to the bytes underlying the Memory.

Panics

Panics if ctx does not own this Memory.

pub fn data_mut<'a, T: 'a>( &self, ctx: impl Into<StoreContextMut<'a, T>>, ) -> &'a mut [u8]

Returns an exclusive slice to the bytes underlying the Memory.

Panics

Panics if ctx does not own this Memory.

pub fn data_and_store_mut<'a, T: 'a>( &self, ctx: impl Into<StoreContextMut<'a, T>>, ) -> (&'a mut [u8], &'a mut T)

Returns an exclusive slice to the bytes underlying the Memory, and an exclusive reference to the user provided state.

Panics

Panics if ctx does not own this Memory.

pub fn data_ptr(&self, ctx: impl AsContext) -> *mut u8

Returns the base pointer, in the host’s address space, that the Memory is located at.

Panics

Panics if ctx does not own this Memory.

pub fn data_size(&self, ctx: impl AsContext) -> usize

Returns the byte length of this Memory.

The returned value will be a multiple of the wasm page size, 64k.

Panics

Panics if ctx does not own this Memory.

pub fn read( &self, ctx: impl AsContext, offset: usize, buffer: &mut [u8], ) -> Result<(), MemoryError>

Reads n bytes from memory[offset..offset+n] into buffer where n is the length of buffer.

Errors

If this operation accesses out of bounds linear memory.

Panics

Panics if ctx does not own this Memory.

pub fn write( &self, ctx: impl AsContextMut, offset: usize, buffer: &[u8], ) -> Result<(), MemoryError>

Writes n bytes to memory[offset..offset+n] from buffer where n if the length of buffer.

Errors

If this operation accesses out of bounds linear memory.

Panics

Panics if ctx does not own this Memory.

Trait Implementations

impl Clone for Memory

fn clone(&self) -> Memory

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Memory

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

Formats the value using the given formatter.

impl From<Memory> for Extern

fn from(memory: Memory) -> Self

Converts to this type from the input type.

impl Copy for Memory