Wrap EVMC result

.bumpversion.cfg

@@ -29,4 +29,3 @@ search = version = \"{current_version}\"
 
 [bumpversion:file:bindings/rust/evmc-vm/Cargo.toml]
 search = version = \"{current_version}\"
-

bindings/rust/evmc-vm/Cargo.toml

@@ -9,3 +9,4 @@ edition = "2018"
 
 [dependencies]
 evmc-sys = { path = "../evmc-sys" }
+libc = "0.2.48"

bindings/rust/evmc-vm/src/lib.rs

@@ -5,3 +5,32 @@ pub use evmc_sys as ffi;
 // TODO: Add convenient helpers for evmc_result
 // TODO: Add convenient helpers for evmc_execute
 // TODO: Add a derive macro here for creating evmc_create
+
+//pub fn destroy_result(&mut evmc_result)
+
+/// EVMC result structure.
+pub struct EvmcResult(Box<ffi::evmc_result>);
+
+impl EvmcResult {
+    pub fn release_result(self) {
+        if let Some(release_fn) = self.0.release {
+            unsafe {
+                release_fn(Box::into_raw(self.0));
+            }
+        }
+    }
+
+    pub fn set_release_fn(&mut self, f: extern "C" fn(*const ffi::evmc_result)) {
+        self.0.release = Some(f);
+    }
+
+    pub fn into_raw(self) -> *const ffi::evmc_result {
+        Box::into_raw(self.0)
+    }
+
+    pub fn set_status(&mut self, code: ffi::evmc_status_code) {}
+
+    pub fn set_gas_left(&mut self, gas: i64) {
+        self.0.gas_left = gas;
+    }
+}