Move Webassembly objects to Store and remove Context

Co-authored-by: ptitSeb <sebastien.chev@gmail.com>
Co-authored-by: Manos Pitsidianakis <manos@wasmer.io>

lib/c-api/src/wasm_c_api/function_env.rs

@@ -0,0 +1,63 @@
+use crate::wasm_c_api::store::wasm_store_t;
+use std::ffi::c_void;
+use wasmer_api::FunctionEnv;
+
+#[derive(Clone, Copy)]
+#[repr(C)]
+pub struct FunctionCEnv {
+    #[allow(dead_code)]
+    inner: std::ptr::NonNull<c_void>,
+}
+
+impl FunctionCEnv {
+    #[allow(dead_code)]
+    pub(crate) fn as_ptr(&self) -> *mut c_void {
+        self.inner.as_ptr()
+    }
+}
+
+static NULL_ENV_PLACEHOLDER: u32 = 42;
+
+impl FunctionCEnv {
+    pub(crate) fn new(inner: std::ptr::NonNull<c_void>) -> Self {
+        Self { inner }
+    }
+}
+
+impl Default for FunctionCEnv {
+    fn default() -> Self {
+        Self {
+            inner: unsafe {
+                std::ptr::NonNull::new_unchecked(
+                    &NULL_ENV_PLACEHOLDER as *const u32 as *mut u32 as *mut c_void,
+                )
+            },
+        }
+    }
+}
+
+unsafe impl Send for FunctionCEnv {}
+
+#[derive(Clone)]
+#[allow(non_camel_case_types)]
+#[repr(C)]
+pub struct wasmer_funcenv_t {
+    inner: FunctionCEnv,
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn wasmer_funcenv_new(
+    store: Option<&mut wasm_store_t>,
+    mut data: *mut c_void,
+) -> Option<Box<wasmer_funcenv_t>> {
+    let store = store?;
+    if data.is_null() {
+        data = &NULL_ENV_PLACEHOLDER as *const u32 as *mut u32 as *mut c_void;
+    }
+    let inner = FunctionCEnv::new(std::ptr::NonNull::new_unchecked(data));
+    let _ = FunctionEnv::new(&mut store.inner.store_mut(), inner);
+    Some(Box::new(wasmer_funcenv_t { inner }))
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn wasmer_funcenv_delete(_funcenv: Option<Box<wasmer_funcenv_t>>) {}