Instance now pulls state from the ImportObject

lib/runtime-core/src/import.rs

@@ -3,8 +3,8 @@ use hashbrown::{hash_map::Entry, HashMap};
 use std::collections::VecDeque;
 use std::{
     cell::{Ref, RefCell},
-    rc::Rc,
     ffi::c_void,
+    rc::Rc,
 };
 
 pub trait LikeNamespace {
@@ -58,7 +58,7 @@ impl ImportObject {
         }
     }
 
-    pub fn new_with_data<F>(state_creator: F) -> Self 
+    pub fn new_with_data<F>(state_creator: F) -> Self
     where
         F: Fn() -> (*mut c_void, fn(*mut c_void)) + 'static,
     {
@@ -68,6 +68,10 @@ impl ImportObject {
         }
     }
 
+    pub(crate) fn call_state_creator(&self) -> Option<(*mut c_void, fn(*mut c_void))> {
+        self.state_creator.as_ref().map(|state_gen| state_gen())
+    }
+
     /// Register anything that implements `LikeNamespace` as a namespace.
     ///
     /// # Usage:

lib/runtime-core/src/instance.rs

@@ -63,7 +63,16 @@ impl Instance {
         // Initialize the vm::Ctx in-place after the backing
         // has been boxed.
         unsafe {
-            *inner.vmctx = vm::Ctx::new(&mut inner.backing, &mut inner.import_backing, &module)
+            *inner.vmctx = match imports.call_state_creator() {
+                Some((data, dtor)) => vm::Ctx::new_with_data(
+                    &mut inner.backing,
+                    &mut inner.import_backing,
+                    &module,
+                    data,
+                    dtor,
+                ),
+                None => vm::Ctx::new(&mut inner.backing, &mut inner.import_backing, &module),
+            };
         };
 
         let instance = Instance {

lib/runtime-core/src/macros.rs

@@ -37,7 +37,7 @@ macro_rules! func {
 ///         "foo" => func!(foo),
 ///     },
 /// };
-/// 
+///
 /// let imports_with_state = imports! {
 ///     || (0 as _, |_a| {}),
 ///     "env" => {

lib/runtime-core/src/vm.rs

@@ -25,7 +25,7 @@ pub struct Ctx {
     module: *const ModuleInner,
 
     pub data: *mut c_void,
-    pub data_finalizer: Option<extern "C" fn(data: *mut c_void)>,
+    pub data_finalizer: Option<fn(data: *mut c_void)>,
 }
 
 /// The internal context of the currently running WebAssembly instance.
@@ -100,7 +100,7 @@ impl Ctx {
         import_backing: &mut ImportBacking,
         module: &ModuleInner,
         data: *mut c_void,
-        data_finalizer: extern "C" fn(*mut c_void),
+        data_finalizer: fn(*mut c_void),
     ) -> Self {
         Self {
             internal: InternalCtx {