Struct wasmtime_runtime::StorePtr

pub struct StorePtr(_);

A pointer to a Store. This Option<*mut dyn Store> is wrapped in a struct so that the function to create a &mut dyn Store is a method on a member of InstanceAllocationRequest, rather than on a &mut InstanceAllocationRequest itself, because several use-sites require a split mut borrow on the InstanceAllocationRequest.

Implementations

impl StorePtr

pub fn empty() -> Self

A pointer to no Store.

pub fn new(ptr: *mut dyn Store) -> Self

A pointer to a Store.

pub fn as_raw(&self) -> Option<*mut dyn Store>

The raw contents of this struct

Examples found in repository

src/instance.rs (line 914)

    unsafe fn initialize_vmctx(
        &mut self,
        module: &Module,
        offsets: &VMOffsets<HostPtr>,
        store: StorePtr,
        imports: Imports,
    ) {
        assert!(std::ptr::eq(module, self.module().as_ref()));

        *self.vmctx_plus_offset(offsets.vmctx_magic()) = VMCONTEXT_MAGIC;
        self.set_callee(None);
        self.set_store(store.as_raw());

        // Initialize shared signatures
        let signatures = self.runtime_info.signature_ids();
        *self.vmctx_plus_offset(offsets.vmctx_signature_ids_array()) = signatures.as_ptr();

        // Initialize the built-in functions
        *self.vmctx_plus_offset(offsets.vmctx_builtin_functions()) = &VMBuiltinFunctionsArray::INIT;

        // Initialize the imports
        debug_assert_eq!(imports.functions.len(), module.num_imported_funcs);
        ptr::copy_nonoverlapping(
            imports.functions.as_ptr(),
            self.vmctx_plus_offset(offsets.vmctx_imported_functions_begin()),
            imports.functions.len(),
        );
        debug_assert_eq!(imports.tables.len(), module.num_imported_tables);
        ptr::copy_nonoverlapping(
            imports.tables.as_ptr(),
            self.vmctx_plus_offset(offsets.vmctx_imported_tables_begin()),
            imports.tables.len(),
        );
        debug_assert_eq!(imports.memories.len(), module.num_imported_memories);
        ptr::copy_nonoverlapping(
            imports.memories.as_ptr(),
            self.vmctx_plus_offset(offsets.vmctx_imported_memories_begin()),
            imports.memories.len(),
        );
        debug_assert_eq!(imports.globals.len(), module.num_imported_globals);
        ptr::copy_nonoverlapping(
            imports.globals.as_ptr(),
            self.vmctx_plus_offset(offsets.vmctx_imported_globals_begin()),
            imports.globals.len(),
        );

        // N.B.: there is no need to initialize the anyfuncs array because
        // we eagerly construct each element in it whenever asked for a
        // reference to that element. In other words, there is no state
        // needed to track the lazy-init, so we don't need to initialize
        // any state now.

        // Initialize the defined tables
        let mut ptr = self.vmctx_plus_offset(offsets.vmctx_tables_begin());
        for i in 0..module.table_plans.len() - module.num_imported_tables {
            ptr::write(ptr, self.tables[DefinedTableIndex::new(i)].vmtable());
            ptr = ptr.add(1);
        }

        // Initialize the defined memories. This fills in both the
        // `defined_memories` table and the `owned_memories` table at the same
        // time. Entries in `defined_memories` hold a pointer to a definition
        // (all memories) whereas the `owned_memories` hold the actual
        // definitions of memories owned (not shared) in the module.
        let mut ptr = self.vmctx_plus_offset(offsets.vmctx_memories_begin());
        let mut owned_ptr = self.vmctx_plus_offset(offsets.vmctx_owned_memories_begin());
        for i in 0..module.memory_plans.len() - module.num_imported_memories {
            let defined_memory_index = DefinedMemoryIndex::new(i);
            let memory_index = module.memory_index(defined_memory_index);
            if module.memory_plans[memory_index].memory.shared {
                let def_ptr = self.memories[defined_memory_index]
                    .as_shared_memory()
                    .unwrap()
                    .vmmemory_ptr();
                ptr::write(ptr, def_ptr.cast_mut());
            } else {
                ptr::write(owned_ptr, self.memories[defined_memory_index].vmmemory());
                ptr::write(ptr, owned_ptr);
                owned_ptr = owned_ptr.add(1);
            }
            ptr = ptr.add(1);
        }

        // Initialize the defined globals
        self.initialize_vmctx_globals(module);
    }