Struct wasmtime_runtime::Mmap

pub struct Mmap { /* private fields */ }

A simple struct consisting of a page-aligned pointer to page-aligned and initially-zeroed memory and a length.

Implementations

impl Mmap

pub fn new() -> Self

Construct a new empty instance of Mmap.

pub fn with_at_least(size: usize) -> Result<Self>

Create a new Mmap pointing to at least size bytes of page-aligned accessible memory.

pub fn from_file(path: &Path) -> Result<Self>

Creates a new Mmap by opening the file located at path and mapping it into memory.

The memory is mapped in read-only mode for the entire file. If portions of the file need to be modified then the region crate can be use to alter permissions of each page.

The memory mapping and the length of the file within the mapping are returned.

pub fn accessible_reserved(
    accessible_size: usize,
    mapping_size: usize
) -> Result<Self>

Create a new Mmap pointing to accessible_size bytes of page-aligned accessible memory, within a reserved mapping of mapping_size bytes. accessible_size and mapping_size must be native page-size multiples.

pub fn make_accessible(&mut self, start: usize, len: usize) -> Result<()>

Make the memory starting at start and extending for len bytes accessible. start and len must be native page-size multiples and describe a range within self’s reserved memory.

pub fn as_slice(&self) -> &[u8]

Return the allocated memory as a slice of u8.

pub fn as_mut_slice(&mut self) -> &mut [u8]

Return the allocated memory as a mutable slice of u8.

pub fn as_ptr(&self) -> *const u8

Return the allocated memory as a pointer to u8.

pub fn as_mut_ptr(&self) -> *mut u8

Return the allocated memory as a mutable pointer to u8.

pub fn len(&self) -> usize

Return the length of the allocated memory.

pub fn is_empty(&self) -> bool

Return whether any memory has been allocated.

pub fn is_readonly(&self) -> bool

Returns whether the underlying mapping is readonly, meaning that attempts to write will fault.

pub unsafe fn make_writable(&self, range: Range<usize>) -> Result<()>

Makes the specified range within this Mmap to be read/write.

pub unsafe fn make_executable(&self, range: Range<usize>) -> Result<()>

Makes the specified range within this Mmap to be read/execute.

pub fn original_file(&self) -> Option<&Arc<File>>

Returns the underlying file that this mmap is mapping, if present.

Trait Implementations

impl Debug for Mmap

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

Formats the value using the given formatter.

impl Drop for Mmap

fn drop(&mut self)

Executes the destructor for this type.