1 #include "node_api.h"
2 #include "assert.h"
3 #include "uv.h"
4 #include <stdlib.h>
5 #include "../../js-native-api/common.h"
6 
7 static int cleanup_hook_count = 0;
MustNotCall(napi_async_cleanup_hook_handle hook, void* arg)8 static void MustNotCall(napi_async_cleanup_hook_handle hook, void* arg) {
9   assert(0);
10 }
11 
12 struct AsyncData {
13   uv_async_t async;
14   napi_env env;
15   napi_async_cleanup_hook_handle handle;
16 };
17 
CreateAsyncDatanull18 static struct AsyncData* CreateAsyncData() {
19   struct AsyncData* data = (struct AsyncData*) malloc(sizeof(struct AsyncData));
20   data->handle = NULL;
21   return data;
22 }
23 
AfterCleanupHookTwo(uv_handle_t* handle)24 static void AfterCleanupHookTwo(uv_handle_t* handle) {
25   cleanup_hook_count++;
26   struct AsyncData* data = (struct AsyncData*) handle->data;
27   napi_status status = napi_remove_async_cleanup_hook(data->handle);
28   assert(status == napi_ok);
29   free(data);
30 }
31 
AfterCleanupHookOne(uv_async_t* async)32 static void AfterCleanupHookOne(uv_async_t* async) {
33   cleanup_hook_count++;
34   uv_close((uv_handle_t*) async, AfterCleanupHookTwo);
35 }
36 
AsyncCleanupHook(napi_async_cleanup_hook_handle handle, void* arg)37 static void AsyncCleanupHook(napi_async_cleanup_hook_handle handle, void* arg) {
38   cleanup_hook_count++;
39   struct AsyncData* data = (struct AsyncData*) arg;
40   uv_loop_t* loop;
41   napi_status status = napi_get_uv_event_loop(data->env, &loop);
42   assert(status == napi_ok);
43   int err = uv_async_init(loop, &data->async, AfterCleanupHookOne);
44   assert(err == 0);
45 
46   data->async.data = data;
47   data->handle = handle;
48   uv_async_send(&data->async);
49 }
50 
ObjectFinalizer(napi_env env, void* data, void* hint)51 static void ObjectFinalizer(napi_env env, void* data, void* hint) {
52   // AsyncCleanupHook and its subsequent callbacks are called twice.
53   assert(cleanup_hook_count == 6);
54 
55   napi_ref* ref = data;
56   NODE_API_CALL_RETURN_VOID(env, napi_delete_reference(env, *ref));
57   free(ref);
58 }
59 
CreateObjectWrap(napi_env env)60 static void CreateObjectWrap(napi_env env) {
61   napi_value js_obj;
62   napi_ref* ref = malloc(sizeof(*ref));
63   NODE_API_CALL_RETURN_VOID(env, napi_create_object(env, &js_obj));
64   NODE_API_CALL_RETURN_VOID(
65       env, napi_wrap(env, js_obj, ref, ObjectFinalizer, NULL, ref));
66   // create a strong reference so that the finalizer is called at shutdown.
67   NODE_API_CALL_RETURN_VOID(env, napi_reference_ref(env, *ref, NULL));
68 }
69 
Init(napi_env env, napi_value exports)70 static napi_value Init(napi_env env, napi_value exports) {
71   // Reinitialize the static variable to be compatible with musl libc.
72   cleanup_hook_count = 0;
73   // Create object wrap before cleanup hooks.
74   CreateObjectWrap(env);
75 
76   {
77     struct AsyncData* data = CreateAsyncData();
78     data->env = env;
79     napi_add_async_cleanup_hook(env, AsyncCleanupHook, data, &data->handle);
80   }
81 
82   {
83     struct AsyncData* data = CreateAsyncData();
84     data->env = env;
85     napi_add_async_cleanup_hook(env, AsyncCleanupHook, data, NULL);
86   }
87 
88   {
89     napi_async_cleanup_hook_handle must_not_call_handle;
90     napi_add_async_cleanup_hook(
91         env, MustNotCall, NULL, &must_not_call_handle);
92     napi_remove_async_cleanup_hook(must_not_call_handle);
93   }
94 
95   // Create object wrap after cleanup hooks.
96   CreateObjectWrap(env);
97 
98   return NULL;
99 }
100 
101 NAPI_MODULE(NODE_GYP_MODULE_NAME, Init)
102