Merge pull request #15339 from ncteisen/new-delete-hack

Add Single Point of Maintenance for New/Delete friend Declarations

src/core/ext/filters/client_channel/lb_policy.h

@@ -162,9 +162,7 @@ class LoadBalancingPolicy
   GRPC_ABSTRACT_BASE_CLASS
 
  protected:
-  // So Delete() can access our protected dtor.
-  template <typename T>
-  friend void Delete(T*);
+  GPRC_ALLOW_CLASS_TO_USE_NON_PUBLIC_DELETE
 
   explicit LoadBalancingPolicy(const Args& args);
   virtual ~LoadBalancingPolicy();

src/core/ext/filters/client_channel/resolver.h

@@ -105,9 +105,7 @@ class Resolver : public InternallyRefCountedWithTracing<Resolver> {
   GRPC_ABSTRACT_BASE_CLASS
 
  protected:
-  // So Delete() can access our protected dtor.
-  template <typename T>
-  friend void Delete(T*);
+  GPRC_ALLOW_CLASS_TO_USE_NON_PUBLIC_DELETE
 
   /// Does NOT take ownership of the reference to \a combiner.
   // TODO(roth): Once we have a C++-like interface for combiners, this

src/core/lib/gprpp/memory.h

@@ -27,6 +27,17 @@
 #include <memory>
 #include <utility>
 
+// Add this to a class that want to use Delete(), but has a private or
+// protected destructor.
+#define GPRC_ALLOW_CLASS_TO_USE_NON_PUBLIC_DELETE \
+  template <typename T>                           \
+  friend void Delete(T*);
+// Add this to a class that want to use New(), but has a private or
+// protected constructor.
+#define GPRC_ALLOW_CLASS_TO_USE_NON_PUBLIC_NEW \
+  template <typename T, typename... Args>      \
+  friend T* New(Args&&...);
+
 namespace grpc_core {
 
 // The alignment of memory returned by gpr_malloc().

src/core/lib/gprpp/orphanable.h

@@ -83,9 +83,7 @@ class InternallyRefCounted : public Orphanable {
   GRPC_ABSTRACT_BASE_CLASS
 
  protected:
-  // Allow Delete() to access destructor.
-  template <typename T>
-  friend void Delete(T*);
+  GPRC_ALLOW_CLASS_TO_USE_NON_PUBLIC_DELETE
 
   // Allow RefCountedPtr<> to access Unref() and IncrementRefCount().
   friend class RefCountedPtr<Child>;
@@ -128,9 +126,7 @@ class InternallyRefCountedWithTracing : public Orphanable {
   GRPC_ABSTRACT_BASE_CLASS
 
  protected:
-  // Allow Delete() to access destructor.
-  template <typename T>
-  friend void Delete(T*);
+  GPRC_ALLOW_CLASS_TO_USE_NON_PUBLIC_DELETE
 
   // Allow RefCountedPtr<> to access Unref() and IncrementRefCount().
   friend class RefCountedPtr<Child>;

src/core/lib/gprpp/ref_counted.h

@@ -65,9 +65,7 @@ class RefCounted {
   GRPC_ABSTRACT_BASE_CLASS
 
  protected:
-  // Allow Delete() to access destructor.
-  template <typename T>
-  friend void Delete(T*);
+  GPRC_ALLOW_CLASS_TO_USE_NON_PUBLIC_DELETE
 
   RefCounted() { gpr_ref_init(&refs_, 1); }
 
@@ -135,9 +133,7 @@ class RefCountedWithTracing {
   GRPC_ABSTRACT_BASE_CLASS
 
  protected:
-  // Allow Delete() to access destructor.
-  template <typename T>
-  friend void Delete(T*);
+  GPRC_ALLOW_CLASS_TO_USE_NON_PUBLIC_DELETE
 
   RefCountedWithTracing()
       : RefCountedWithTracing(static_cast<TraceFlag*>(nullptr)) {}