1 //===- IPDBEnumChildren.h - base interface for child enumerator -*- 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 LLVM_DEBUGINFO_PDB_IPDBENUMCHILDREN_H
10 #define LLVM_DEBUGINFO_PDB_IPDBENUMCHILDREN_H
11 
12 #include "llvm/DebugInfo/CodeView/LazyRandomTypeCollection.h"
13 #include <cassert>
14 #include <cstdint>
15 #include <memory>
16 
17 namespace llvm {
18 namespace pdb {
19 
20 template <typename ChildType> class IPDBEnumChildren {
21 public:
22   using ChildTypePtr = std::unique_ptr<ChildType>;
23   using MyType = IPDBEnumChildren<ChildType>;
24 
25   virtual ~IPDBEnumChildren() = default;
26 
27   virtual uint32_t getChildCount() const = 0;
28   virtual ChildTypePtr getChildAtIndex(uint32_t Index) const = 0;
29   virtual ChildTypePtr getNext() = 0;
30   virtual void reset() = 0;
31 };
32 
33 template <typename ChildType>
34 class NullEnumerator : public IPDBEnumChildren<ChildType> {
getChildCount()35   uint32_t getChildCount() const override { return 0; }
getChildAtIndex(uint32_t Index)36   std::unique_ptr<ChildType> getChildAtIndex(uint32_t Index) const override {
37     return nullptr;
38   }
getNext()39   std::unique_ptr<ChildType> getNext() override { return nullptr; }
reset()40   void reset() override {}
41 };
42 
43 } // end namespace pdb
44 } // end namespace llvm
45 
46 #endif // LLVM_DEBUGINFO_PDB_IPDBENUMCHILDREN_H
47