Files
clang-p2996/lldb/source/Plugins/Language/CPlusPlus/LibCxxQueue.cpp
Adrian Prantl 624ea68cbc Change GetNumChildren()/CalculateNumChildren() methods return llvm::Expected (#84219)
Change GetNumChildren()/CalculateNumChildren() methods return
llvm::Expected

This is an NFC change that does not yet add any error handling or change
any code to return any errors.

This is the second big change in the patch series started with
https://github.com/llvm/llvm-project/pull/83501

A follow-up PR will wire up error handling.
2024-03-08 16:03:04 -08:00

66 lines
2.2 KiB
C++

//===-- LibCxxQueue.cpp ---------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "LibCxx.h"
#include "lldb/DataFormatters/FormattersHelpers.h"
using namespace lldb;
using namespace lldb_private;
namespace {
class QueueFrontEnd : public SyntheticChildrenFrontEnd {
public:
QueueFrontEnd(ValueObject &valobj) : SyntheticChildrenFrontEnd(valobj) {
Update();
}
size_t GetIndexOfChildWithName(ConstString name) override {
return m_container_sp ? m_container_sp->GetIndexOfChildWithName(name)
: UINT32_MAX;
}
bool MightHaveChildren() override { return true; }
lldb::ChildCacheState Update() override;
llvm::Expected<uint32_t> CalculateNumChildren() override {
return m_container_sp ? m_container_sp->GetNumChildren() : 0;
}
ValueObjectSP GetChildAtIndex(uint32_t idx) override {
return m_container_sp ? m_container_sp->GetChildAtIndex(idx)
: nullptr;
}
private:
// The lifetime of a ValueObject and all its derivative ValueObjects
// (children, clones, etc.) is managed by a ClusterManager. These
// objects are only destroyed when every shared pointer to any of them
// is destroyed, so we must not store a shared pointer to any ValueObject
// derived from our backend ValueObject (since we're in the same cluster).
ValueObject* m_container_sp = nullptr;
};
} // namespace
lldb::ChildCacheState QueueFrontEnd::Update() {
m_container_sp = nullptr;
ValueObjectSP c_sp = m_backend.GetChildMemberWithName("c");
if (!c_sp)
return lldb::ChildCacheState::eRefetch;
m_container_sp = c_sp->GetSyntheticValue().get();
return lldb::ChildCacheState::eRefetch;
}
SyntheticChildrenFrontEnd *
formatters::LibcxxQueueFrontEndCreator(CXXSyntheticChildren *,
lldb::ValueObjectSP valobj_sp) {
if (valobj_sp)
return new QueueFrontEnd(*valobj_sp);
return nullptr;
}