Question

我的代码：

struct WeakData {
    context* c;
    std::vector<UniquePersistent<Object>>::iterator i;
};

void WeakPtrCallback(const v8::WeakCallbackData<v8::Object, WeakData>& data) {
    printf("weak callback");
    fflush(stdout);
    // crashes always after exit from this callback
}

Local<Object> wrapDocumentSelection(Isolate* isolate, cDocumentSelection* selection) {
    EscapableHandleScope handle_scope(isolate);
    auto ctx = isolate->GetCurrentContext();
    Context::Scope context_scope(ctx);

    Local<External> contextWrap = Local<External>::Cast(
            Handle<Object>::Cast(isolate->GetCurrentContext()->Global()->GetPrototype())->GetInternalField(0));
    context* c = static_cast<context*>(contextWrap->Value());

    Local<ObjectTemplate> documentSelectionTemplate = Local<ObjectTemplate>::New(isolate, c->documentSelectionTemplate);

    Local<Object> jsSelection = documentSelectionTemplate->NewInstance(ctx).ToLocalChecked();
    jsSelection->SetInternalField(0, External::New(isolate, selection));
    jsSelection->Set(ctx, String::NewFromUtf8(isolate, "length"), Integer::New(isolate, selection->Length));

    c->trackingObjects.push_back(UniquePersistent<Object>(isolate, jsSelection));
    auto &p = c->trackingObjects.back();
    auto it = c->trackingObjects.end();
    it--;

    WeakData* wd = new WeakData;
    wd->c = c;
    wd->i = it;

    p.Reset(isolate, jsSelection);
    p.SetWeak<WeakData>(NULL, WeakPtrCallback);
    isolate->AdjustAmountOfExternalAllocatedMemory(1024);

    return handle_scope.Escape(jsSelection);
}

在上下文中我保持所有持久句柄的向量在WeakPtrCallback中，我需要清理一些外部分配的资源

v8错误：

#
# Fatal error in ../src/global-handles.cc, line 325
# Check failed: state() != NEAR_DEATH.
#

关于https://strongloop.com/strongblog/node-js-v0-12-c-apis-breaking/ 我不需要在回调中执行任何与v8相关的清理

自动处理持久性存储单元。如果你想用.ClearWeak（）恢复它，请保留对原始v8 :: Persistent的引用。

我也试过使用Persistent和Persistent<Value, CopyablePersistentTraits<Value>> - 同样的错误...... 有什么建议吗？

Answer 1

好吧，我的C ++似乎不够好我跟踪问题以解决向量问题，由于某种原因它无法正确删除所需的元素，我猜迭代器是索引绑定的，所以删除一些先前的元素会破坏所有进一步的迭代器引用......

切换到std :: map并且不断递增计数器作为键完全解决了问题

v8持久性SetWeak与NEAR_DEATH崩溃

1 个答案: