Function main

example/callback.c:63–167

int main(int argc, const char* argv[]) {
  // Initialize.
  printf("Initializing...\n");
  wasm_engine_t* engine = wasm_engine_new();
  wasm_store_t* store = wasm_store_new(engine);

  // Load binary.
  printf("Loading binary...\n");
  FILE* file = fopen("callback.wasm", "rb");
  if (!file) {
    printf("> Error loading module!\n");
    return 1;
  }
  fseek(file, 0L, SEEK_END);
  size_t file_size = ftell(file);
  fseek(file, 0L, SEEK_SET);
  wasm_byte_vec_t binary;
  wasm_byte_vec_new_uninitialized(&binary, file_size);
  if (fread(binary.data, file_size, 1, file) != 1) {
    printf("> Error loading module!\n");
    return 1;
  }
  fclose(file);

  // Compile.
  printf("Compiling module...\n");
  own wasm_module_t* module = wasm_module_new(store, &binary);
  if (!module) {
    printf("> Error compiling module!\n");
    return 1;
  }

  wasm_byte_vec_delete(&binary);

  // Create external print functions.
  printf("Creating callback...\n");
  own wasm_functype_t* print_type = wasm_functype_new_1_1(wasm_valtype_new_i32(), wasm_valtype_new_i32());
  own wasm_func_t* print_func = wasm_func_new(store, print_type, print_callback);

  int i = 42;
  own wasm_functype_t* closure_type = wasm_functype_new_0_1(wasm_valtype_new_i32());
  own wasm_func_t* closure_func = wasm_func_new_with_env(store, closure_type, closure_callback, &i, NULL);

  wasm_functype_delete(print_type);
  wasm_functype_delete(closure_type);

  // Instantiate.
  printf("Instantiating module...\n");
  wasm_extern_t* externs[] = {
    wasm_func_as_extern(print_func), wasm_func_as_extern(closure_func)
  };
  wasm_extern_vec_t imports = WASM_ARRAY_VEC(externs);
  own wasm_instance_t* instance =
    wasm_instance_new(store, module, &imports, NULL);
  if (!instance) {
    printf("> Error instantiating module!\n");
    return 1;
  }