1 files changed, 36 insertions, 4 deletions
diff --git a/src/core/lib/gprpp/ref_counted.h b/src/core/lib/gprpp/ref_counted.h
index c68118a71a..ab589fc01a 100644
--- a/src/core/lib/gprpp/ref_counted.h
+++ b/src/core/lib/gprpp/ref_counted.h
@@ -26,16 +26,28 @@
 #include "src/core/lib/gprpp/abstract.h"
 #include "src/core/lib/gprpp/debug_location.h"
 #include "src/core/lib/gprpp/memory.h"
+#include "src/core/lib/gprpp/ref_counted_ptr.h"
 
 namespace grpc_core {
 
 // A base class for reference-counted objects.
 // New objects should be created via New() and start with a refcount of 1.
 // When the refcount reaches 0, the object will be deleted via Delete().
+//
+// This will commonly be used by CRTP (curiously-recurring template pattern)
+// e.g., class MyClass : public RefCounted<MyClass>
+template <typename Child>
 class RefCounted {
  public:
-  void Ref() { gpr_ref(&refs_); }
+  RefCountedPtr<Child> Ref() GRPC_MUST_USE_RESULT {
+    IncrementRefCount();
+    return RefCountedPtr<Child>(static_cast<Child*>(this));
+  }
 
+  // TODO(roth): Once all of our code is converted to C++ and can use
+  // RefCountedPtr<> instead of manual ref-counting, make this method
+  // private, since it will only be used by RefCountedPtr<>, which is a
+  // friend of this class.
   void Unref() {
     if (gpr_unref(&refs_)) {
       Delete(this);
@@ -58,6 +70,11 @@ class RefCounted {
   virtual ~RefCounted() {}
 
  private:
+  // Allow RefCountedPtr<> to access IncrementRefCount().
+  friend class RefCountedPtr<Child>;
+
+  void IncrementRefCount() { gpr_ref(&refs_); }
+
   gpr_refcount refs_;
 };
 
@@ -67,20 +84,30 @@ class RefCounted {
 // pointers and legacy code that is manually calling Ref() and Unref().
 // Once all of our code is converted to idiomatic C++, we may be able to
 // eliminate this class.
+template <typename Child>
 class RefCountedWithTracing {
  public:
-  void Ref() { gpr_ref(&refs_); }
+  RefCountedPtr<Child> Ref() GRPC_MUST_USE_RESULT {
+    IncrementRefCount();
+    return RefCountedPtr<Child>(static_cast<Child*>(this));
+  }
 
-  void Ref(const DebugLocation& location, const char* reason) {
+  RefCountedPtr<Child> Ref(const DebugLocation& location,
+                           const char* reason) GRPC_MUST_USE_RESULT {
     if (location.Log() && trace_flag_ != nullptr && trace_flag_->enabled()) {
       gpr_atm old_refs = gpr_atm_no_barrier_load(&refs_.count);
       gpr_log(GPR_DEBUG, "%s:%p %s:%d ref %" PRIdPTR " -> %" PRIdPTR " %s",
               trace_flag_->name(), this, location.file(), location.line(),
               old_refs, old_refs + 1, reason);
     }
-    Ref();
+    return Ref();
   }
 
+  // TODO(roth): Once all of our code is converted to C++ and can use
+  // RefCountedPtr<> instead of manual ref-counting, make the Unref() methods
+  // private, since they will only be used by RefCountedPtr<>, which is a
+  // friend of this class.
+
   void Unref() {
     if (gpr_unref(&refs_)) {
       Delete(this);
@@ -124,6 +151,11 @@ class RefCountedWithTracing {
   virtual ~RefCountedWithTracing() {}
 
  private:
+  // Allow RefCountedPtr<> to access IncrementRefCount().
+  friend class RefCountedPtr<Child>;
+
+  void IncrementRefCount() { gpr_ref(&refs_); }
+
   TraceFlag* trace_flag_ = nullptr;
   gpr_refcount refs_;
 };