1//===-- Baton.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_BATON_H 10#define LLDB_UTILITY_BATON_H 11 12#include "lldb/lldb-enumerations.h" 13#include "lldb/lldb-public.h" 14 15#include "llvm/Support/raw_ostream.h" 16 17#include <memory> 18 19namespace lldb_private { 20class Stream; 21} 22 23namespace lldb_private { 24 25/// \class Baton Baton.h "lldb/Core/Baton.h" 26/// A class designed to wrap callback batons so they can cleanup 27/// any acquired resources 28/// 29/// This class is designed to be used by any objects that have a callback 30/// function that takes a baton where the baton might need to 31/// free/delete/close itself. 32/// 33/// The default behavior is to not free anything. Subclasses can free any 34/// needed resources in their destructors. 35class Baton { 36public: 37 Baton() = default; 38 virtual ~Baton() = default; 39 40 virtual void *data() = 0; 41 42 virtual void GetDescription(llvm::raw_ostream &s, 43 lldb::DescriptionLevel level, 44 unsigned indentation) const = 0; 45}; 46 47class UntypedBaton : public Baton { 48public: 49 UntypedBaton(void *Data) : m_data(Data) {} 50 ~UntypedBaton() override { 51 // The default destructor for an untyped baton does NOT attempt to clean up 52 // anything in m_data. 53 } 54 55 void *data() override { return m_data; } 56 void GetDescription(llvm::raw_ostream &s, lldb::DescriptionLevel level, 57 unsigned indentation) const override; 58 59 void *m_data; // Leave baton public for easy access 60}; 61 62template <typename T> class TypedBaton : public Baton { 63public: 64 explicit TypedBaton(std::unique_ptr<T> Item) : Item(std::move(Item)) {} 65 66 T *getItem() { return Item.get(); } 67 const T *getItem() const { return Item.get(); } 68 69 void *data() override { return Item.get(); } 70 void GetDescription(llvm::raw_ostream &s, lldb::DescriptionLevel level, 71 unsigned indentation) const override {} 72 73protected: 74 std::unique_ptr<T> Item; 75}; 76 77} // namespace lldb_private 78 79#endif // LLDB_UTILITY_BATON_H 80