请解释napi_add_async_cleanup_hook接口的功能及使用方式？

Question

如题：请解释napi_add_async_cleanup_hook接口的功能及使用方式。
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Answer 1

napi_add_async_cleanup_hook接口用于注册一个异步清理钩子函数，该函数将在环境退出时异步执行。在C++代码中，先定义包含环境、测试数据、uv_async_s结构和清理钩子句柄等成员的结构体（如AsyncContent），实现异步执行环境清理工作的函数（如AsyncWork）和异步清理钩子函数（如AsyncCleanup），在AsyncCleanup函数中获取libUv循环实例并初始化异步句柄，发送异步信号触发清理工作。然后在NapiAsyncCleanUpHook函数中分配AsyncContent内存，复制测试数据，调用napi_add_async_cleanup_hook接口注册异步清理钩子函数，传入环境、异步清理钩子函数和相关数据结构，最后返回一个表示成功的napi_value。示例代码如下：

#include <malloc.h>
#include <string.h>
#include "napi/native_api.h"
#include "uv.h"

typedef struct {
    napi_env env;
    void *testData;
    uv_async_s asyncUv;
    napi_async_cleanup_hook_handle cleanupHandle;
} AsyncContent;

static void FinalizeWork(uv_handle_s *handle) {
    AsyncContent *asyncData = reinterpret_cast<AsyncContent *>(handle->data);
    napi_status result = napi_remove_async_cleanup_hook(asyncData->cleanupHandle);
    if (result!= napi_ok) {
        napi_throw_error(asyncData->env, nullptr, "Test Node-API napi_remove_async_cleanup_hook failed");
    }
    free(asyncData);
}

static void AsyncWork(uv_async_s *async) {
    AsyncContent *asyncData = reinterpret_cast<AsyncContent *>(async->data);
    if (asyncData->testData!= nullptr) {
        free(asyncData->testData);
        asyncData->testData = nullptr;
    }
    uv_close((uv_handle_s *)async, FinalizeWork);
}

static void AsyncCleanup(napi_async_cleanup_hook_handle handle, void *info) {
    AsyncContent *data = reinterpret_cast<AsyncContent *>(info);
    uv_loop_s *uvLoop;
    napi_get_uv_event_loop(data->env, &uvLoop);
    uv_async_init(uvLoop, &data->asyncUv, AsyncWork);
    data->asyncUv.data = data;
    data->cleanupHandle = handle;
    uv_async_send(&data->asyncUv);
}

static napi_value NapiAsyncCleanUpHook(napi_env env, napi_callback_info info) {
    AsyncContent *data = reinterpret_cast<AsyncContent *>(malloc(sizeof(AsyncContent)));
    data->env = env;
    data->cleanupHandle = nullptr;
    const char *testDataStr = "TestNapiAsyncCleanUpHook";
    data->testData = strdup(testDataStr);
    if (data->testData == nullptr) {
        napi_throw_error(env, nullptr, "Test Node-API data->testData is nullptr");
    }
    napi_status status = napi_add_async_cleanup_hook(env, AsyncCleanup, data, &data->cleanupHandle);
    if (status!= napi_ok) {
        napi_throw_error(env, nullptr, "Test Node-API napi_add_async_cleanup_hook failed");
    }
    napi_value result = nullptr;
    napi_get_boolean(env, true, &result);
    return result;
}

ArkTS侧调用该接口并通过日志输出结果（如hilog.info(0x0000, 'testTag', 'Test Node-API napi_add_async_cleanup_hook: %{public}s', testNapi.napiAsyncCleanUpHook());）。

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