1 files changed, 78 insertions, 0 deletions
diff --git a/include/lldb/Utility/Baton.h b/include/lldb/Utility/Baton.h
new file mode 100644
index 000000000000..065f2960962d
--- /dev/null
+++ b/include/lldb/Utility/Baton.h
@@ -0,0 +1,78 @@
+//===-- Baton.h -------------------------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef lldb_Baton_h_
+#define lldb_Baton_h_
+
+#include "lldb/lldb-enumerations.h" // for DescriptionLevel
+#include "lldb/lldb-public.h"
+
+#include <memory> // for unique_ptr
+
+namespace lldb_private {
+class Stream;
+}
+
+namespace lldb_private {
+
+//----------------------------------------------------------------------
+/// @class Baton Baton.h "lldb/Core/Baton.h"
+/// @brief A class designed to wrap callback batons so they can cleanup
+///        any acquired resources
+///
+/// This class is designed to be used by any objects that have a
+/// callback function that takes a baton where the baton might need to
+/// free/delete/close itself.
+///
+/// The default behavior is to not free anything. Subclasses can
+/// free any needed resources in their destructors.
+//----------------------------------------------------------------------
+class Baton {
+public:
+  Baton() {}
+  virtual ~Baton() {}
+
+  virtual void *data() = 0;
+
+  virtual void GetDescription(Stream *s,
+                              lldb::DescriptionLevel level) const = 0;
+};
+
+class UntypedBaton : public Baton {
+public:
+  UntypedBaton(void *Data) : m_data(Data) {}
+  virtual ~UntypedBaton() {
+    // The default destructor for an untyped baton does NOT attempt to clean up
+    // anything in m_data.
+  }
+
+  void *data() override { return m_data; }
+  void GetDescription(Stream *s, lldb::DescriptionLevel level) const override;
+
+  void *m_data; // Leave baton public for easy access
+};
+
+template <typename T> class TypedBaton : public Baton {
+public:
+  explicit TypedBaton(std::unique_ptr<T> Item) : Item(std::move(Item)) {}
+
+  T *getItem() { return Item.get(); }
+  const T *getItem() const { return Item.get(); }
+
+  void *data() override { return Item.get(); }
+  virtual void GetDescription(Stream *s,
+                              lldb::DescriptionLevel level) const override {}
+
+protected:
+  std::unique_ptr<T> Item;
+};
+
+} // namespace lldb_private
+
+#endif // lldb_Baton_h_