From f650eccf9ea98eecbd528cca0be0b54d90b10099 Mon Sep 17 00:00:00 2001
From: Phil Miller <phil@intensecomputing.com>
Date: Mon, 23 Nov 2020 19:15:28 -0500
Subject: [PATCH] #156: Get serializeArray working for non-serializable types

---
 src/checkpoint/dispatch/dispatch.h          |  4 ++--
 src/checkpoint/dispatch/dispatch.impl.h     | 23 ++++++++++++++-------
 src/checkpoint/traits/serializable_traits.h |  9 ++------
 tests/unit/test_footprinter.cc              |  6 ------
 4 files changed, 19 insertions(+), 23 deletions(-)

diff --git a/src/checkpoint/dispatch/dispatch.h b/src/checkpoint/dispatch/dispatch.h
index 297e0198..d40b3178 100644
--- a/src/checkpoint/dispatch/dispatch.h
+++ b/src/checkpoint/dispatch/dispatch.h
@@ -194,8 +194,8 @@ buffer::ImplReturnType packBuffer(
   T& target, SerialSizeType size, BufferObtainFnType fn
 );
 
-template <typename Serializer, typename T>
-inline void serializeArray(Serializer& s, T* array, SerialSizeType const len);
+    //template <typename Serializer, typename T>
+    //inline void serializeArray(Serializer& s, T* array, SerialSizeType const len);
 
 template <typename T>
 buffer::ImplReturnType serializeType(T& target, BufferObtainFnType fn = nullptr);
diff --git a/src/checkpoint/dispatch/dispatch.impl.h b/src/checkpoint/dispatch/dispatch.impl.h
index 3ca73889..fbef0a97 100644
--- a/src/checkpoint/dispatch/dispatch.impl.h
+++ b/src/checkpoint/dispatch/dispatch.impl.h
@@ -120,8 +120,11 @@ T* Standard::construct(SerialByteType* mem) {
   return Traverse::reconstruct<T>(mem);
 }
 
-template <typename Serializer, typename T>
-inline void serializeArray(Serializer& s, T* array, SerialSizeType const len) {
+template <
+  typename Serializer,
+  typename T
+>
+inline std::enable_if_t< SerializableTraits<T, Serializer>::is_traversable, void > serializeArray(Serializer& s, T* array, SerialSizeType const len) {
   if (len > 0) {
     Traverse::with<T, Serializer>(*array, s, len);
   }
@@ -129,13 +132,17 @@ inline void serializeArray(Serializer& s, T* array, SerialSizeType const len) {
 
 template <
   typename Serializer,
-  typename T,
-  typename = std::enable_if_t<
-    not SerializableTraits<T>::is_footprintable_v
-  >
+  typename T
 >
-inline void serializeArray(Serializer& s, T* array, SerialSizeType const len) {
-  // count bytes
+inline
+std::enable_if_t<
+  not SerializableTraits<T, Serializer>::is_traversable
+  and
+  std::is_same<Serializer, checkpoint::Footprinter>::value,
+  void
+  >
+serializeArray(Serializer& s, T* array, SerialSizeType const len) {
+  s.addBytes(sizeof(T) * len);
 }
 
 template <typename T>
diff --git a/src/checkpoint/traits/serializable_traits.h b/src/checkpoint/traits/serializable_traits.h
index 3f4af970..e6cda215 100644
--- a/src/checkpoint/traits/serializable_traits.h
+++ b/src/checkpoint/traits/serializable_traits.h
@@ -211,13 +211,8 @@ struct SerializableTraits {
   static constexpr auto const is_serializable =
     has_serialize_function and is_constructible;
 
-  using is_footprintable = std::is_same<
-    std::size_t,
-    decltype(checkpoint::getMemoryFootprint(std::declval<T&>()))
-  >;
-
-  static constexpr auto const is_footprintable_v =
-    is_footprintable::value;
+  static constexpr auto const is_traversable =
+    has_serialize_function or is_bytecopyable;
 };
 
 }  // end namespace checkpoint
diff --git a/tests/unit/test_footprinter.cc b/tests/unit/test_footprinter.cc
index 52ee5186..8ae2a2c0 100644
--- a/tests/unit/test_footprinter.cc
+++ b/tests/unit/test_footprinter.cc
@@ -601,12 +601,6 @@ struct TestNoSerialize {
 TEST_F(TestFootprinter, test_no_serialize) {
   std::vector<TestNoSerialize> v(7);
 
-  std::cout << std::boolalpha;
-  std::cout << SerializableTraits<int>::is_footprintable_v << std::endl;
-  std::cout << SerializableTraits<Test1>::is_footprintable_v << std::endl;
-  std::cout << SerializableTraits<TestNoSerialize>::is_footprintable_v << std::endl;
-  // all 3 return 'true'
-
   EXPECT_EQ(
     checkpoint::getMemoryFootprint(v),
     sizeof(v) + v.capacity() * sizeof(TestNoSerialize)