Newtype Module/Instance

Author: axic

bindings/rust/src/lib.rs

@@ -14,13 +14,11 @@ pub fn validate<T: AsRef<[u8]>>(input: T) -> bool {
 }
 
 /// A parsed and validated WebAssembly 1.0 module.
-pub struct Module {
-    ptr: NonNull<sys::FizzyModule>,
-}
+pub struct Module(*const sys::FizzyModule);
 
 impl Drop for Module {
     fn drop(&mut self) {
-        unsafe { sys::fizzy_free_module(self.ptr.as_ptr()) }
+        unsafe { sys::fizzy_free_module(self.0) }
     }
 }
 
@@ -30,29 +28,28 @@ pub fn parse<T: AsRef<[u8]>>(input: &T) -> Result<Module, ()> {
     if ptr.is_null() {
         return Err(());
     }
-    Ok(Module {
-        ptr: unsafe { NonNull::new_unchecked(ptr as *mut sys::FizzyModule) },
-    })
+    Ok(Module { 0: ptr })
 }
 
 /// An instance of a module.
-pub struct Instance {
-    ptr: NonNull<sys::FizzyInstance>,
-}
+pub struct Instance(NonNull<sys::FizzyInstance>);
 
 impl Drop for Instance {
     fn drop(&mut self) {
-        unsafe { sys::fizzy_free_instance(self.ptr.as_ptr()) }
+        unsafe { sys::fizzy_free_instance(self.0.as_ptr()) }
     }
 }
 
 impl Module {
     /// Create an instance of a module.
     // TODO: support imported functions
     pub fn instantiate(self) -> Result<Instance, ()> {
+        if self.0.is_null() {
+            return Err(());
+        }
         let ptr = unsafe {
             sys::fizzy_instantiate(
-                self.ptr.as_ptr(),
+                self.0,
                 std::ptr::null(),
                 0,
                 std::ptr::null(),
@@ -67,7 +64,7 @@ impl Module {
             return Err(());
         }
         Ok(Instance {
-            ptr: unsafe { NonNull::new_unchecked(ptr) },
+            0: unsafe { NonNull::new_unchecked(ptr) },
         })
     }
 }
@@ -168,7 +165,7 @@ impl Instance {
         depth: i32,
     ) -> ExecutionResult {
         ExecutionResult {
-            0: sys::fizzy_execute(self.ptr.as_ptr(), func_idx, args.as_ptr(), depth),
+            0: sys::fizzy_execute(self.0.as_ptr(), func_idx, args.as_ptr(), depth),
         }
     }
 }