capi: Get module from an instance

Author: gumb0

include/fizzy/fizzy.h

@@ -125,6 +125,12 @@ FizzyInstance* fizzy_instantiate(const FizzyModule* module,
 /// If passed pointer is NULL, has no effect.
 void fizzy_free_instance(FizzyInstance* instance);
 
+/// Get pointer to module of an instance.
+///
+/// @note The returned pointer respresents non-owning, "view"-access to the module and must not be
+/// passed to fizzy_free_module.
+const FizzyModule* fizzy_get_instance_module(FizzyInstance* instance);
+
 /// Get pointer to memory of an instance.
 ///
 /// @returns Pointer to memory data or NULL in case instance doesn't have any memory.

lib/fizzy/capi.cpp

@@ -176,6 +176,11 @@ void fizzy_free_instance(FizzyInstance* instance)
     delete unwrap(instance);
 }
 
+const FizzyModule* fizzy_get_instance_module(FizzyInstance* instance)
+{
+    return wrap(unwrap(instance)->module.get());
+}
+
 uint8_t* fizzy_get_instance_memory_data(FizzyInstance* instance)
 {
     auto& memory = unwrap(instance)->memory;

test/unittests/capi_test.cpp

@@ -116,6 +116,26 @@ TEST(capi, free_instance_null)
     fizzy_free_instance(nullptr);
 }
 
+TEST(capi, get_instance_module)
+{
+    /* wat2wasm
+      (func (param i32 i32))
+    */
+    const auto wasm = from_hex("0061736d0100000001060160027f7f00030201000a040102000b");
+    auto module = fizzy_parse(wasm.data(), wasm.size());
+    EXPECT_NE(module, nullptr);
+
+    auto instance = fizzy_instantiate(module, nullptr, 0);
+    EXPECT_NE(instance, nullptr);
+
+    auto instance_module = fizzy_get_instance_module(instance);
+    EXPECT_NE(instance_module, nullptr);
+
+    EXPECT_EQ(fizzy_get_function_type(instance_module, 0).inputs_size, 2);
+
+    fizzy_free_instance(instance);
+}
+
 TEST(capi, memory_access_no_memory)
 {
     /* wat2wasm