1//===------------------SharedCluster.h --------------------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#ifndef LLDB_UTILITY_SHAREDCLUSTER_H
10#define LLDB_UTILITY_SHAREDCLUSTER_H
11
12#include "lldb/Utility/LLDBAssert.h"
13#include "llvm/ADT/STLExtras.h"
14#include "llvm/ADT/SmallPtrSet.h"
15
16#include <memory>
17#include <mutex>
18
19namespace lldb_private {
20
21template <class T>
22class ClusterManager : public std::enable_shared_from_this<ClusterManager<T>> {
23public:
24 static std::shared_ptr<ClusterManager> Create() {
25 return std::shared_ptr<ClusterManager>(new ClusterManager());
26 }
27
28 ~ClusterManager() {
29 for (T *obj : m_objects)
30 delete obj;
31 }
32
33 void ManageObject(T *new_object) {
34 std::lock_guard<std::mutex> guard(m_mutex);
35 auto ret = m_objects.insert(new_object);
36 assert(ret.second && "ManageObject called twice for the same object?");
37 (void)ret;
38 }
39
40 std::shared_ptr<T> GetSharedPointer(T *desired_object) {
41 std::lock_guard<std::mutex> guard(m_mutex);
42 auto this_sp = this->shared_from_this();
43 size_t count = m_objects.count(desired_object);
44 if (count == 0) {
45 lldbassert(false && "object not found in shared cluster when expected");
46 desired_object = nullptr;
47 }
48 return {std::move(this_sp), desired_object};
49 }
50
51private:
52 ClusterManager() : m_objects() {}
53 // The cluster manager is used primarily to manage the
54 // children of root ValueObjects. So it will always have
55 // one element - the root. Pointers will often have dynamic
56 // values, so having 2 entries is pretty common. It's also
57 // pretty common to have small (2,3) structs, so setting the
58 // static size to 4 will cover those cases with no allocations
59 // w/o wasting too much space.
60 llvm::SmallPtrSet<T *, 4> m_objects;
61 std::mutex m_mutex;
62};
63
64} // namespace lldb_private
65
66#endif // LLDB_UTILITY_SHAREDCLUSTER_H
67

source code of lldb/include/lldb/Utility/SharedCluster.h