Revert "Revert "Allow SerializationTraits to use grpc::ByteBuffer rather than only grpc_byte_buffer""

8 files changed, 340 insertions, 189 deletions

diff --git a/include/grpc++/impl/codegen/byte_buffer.h b/include/grpc++/impl/codegen/byte_buffer.h
new file mode 100644
index 0000000000..87d390c688
--- /dev/null
+++ b/include/grpc++/impl/codegen/byte_buffer.h
@@ -0,0 +1,141 @@
+/*
+ *
+ * Copyright 2017 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+#ifndef GRPCXX_IMPL_CODEGEN_BYTE_BUFFER_H
+#define GRPCXX_IMPL_CODEGEN_BYTE_BUFFER_H
+
+#include <grpc/impl/codegen/byte_buffer.h>
+
+#include <grpc++/impl/codegen/config.h>
+#include <grpc++/impl/codegen/core_codegen_interface.h>
+#include <grpc++/impl/codegen/serialization_traits.h>
+#include <grpc++/impl/codegen/slice.h>
+#include <grpc++/impl/codegen/status.h>
+
+#include <vector>
+
+namespace grpc {
+
+template <class R>
+class CallOpRecvMessage;
+class MethodHandler;
+namespace internal {
+template <class M, class T>
+class MessageDeserializer;
+}
+
+/// A sequence of bytes.
+class ByteBuffer final {
+ public:
+  /// Constuct an empty buffer.
+  ByteBuffer() : buffer_(nullptr) {}
+
+  /// Construct buffer from \a slices, of which there are \a nslices.
+  ByteBuffer(const Slice* slices, size_t nslices);
+
+  /// Constuct a byte buffer by referencing elements of existing buffer
+  /// \a buf. Wrapper of core function grpc_byte_buffer_copy
+  ByteBuffer(const ByteBuffer& buf);
+
+  ~ByteBuffer() {
+    if (buffer_) {
+      g_core_codegen_interface->grpc_byte_buffer_destroy(buffer_);
+    }
+  }
+
+  ByteBuffer& operator=(const ByteBuffer&);
+
+  /// Dump (read) the buffer contents into \a slices.
+  Status Dump(std::vector<Slice>* slices) const;
+
+  /// Remove all data.
+  void Clear() {
+    if (buffer_) {
+      g_core_codegen_interface->grpc_byte_buffer_destroy(buffer_);
+      buffer_ = nullptr;
+    }
+  }
+
+  /// Make a duplicate copy of the internals of this byte
+  /// buffer so that we have our own owned version of it.
+  /// bbuf.Duplicate(); is equivalent to bbuf=bbuf; but is actually readable
+  void Duplicate() {
+    buffer_ = g_core_codegen_interface->grpc_byte_buffer_copy(buffer_);
+  }
+
+  /// Forget underlying byte buffer without destroying
+  /// Use this only for un-owned byte buffers
+  void Release() { buffer_ = nullptr; }
+
+  /// Buffer size in bytes.
+  size_t Length() const;
+
+  /// Swap the state of *this and *other.
+  void Swap(ByteBuffer* other);
+
+  /// Is this ByteBuffer valid?
+  bool Valid() const { return (buffer_ != nullptr); }
+
+ private:
+  friend class SerializationTraits<ByteBuffer, void>;
+  friend class CallOpSendMessage;
+  template <class R>
+  friend class CallOpRecvMessage;
+  friend class CallOpGenericRecvMessage;
+  friend class MethodHandler;
+  template <class M, class T>
+  friend class internal::MessageDeserializer;
+
+  // takes ownership
+  void set_buffer(grpc_byte_buffer* buf) {
+    if (buffer_) {
+      Clear();
+    }
+    buffer_ = buf;
+  }
+
+  grpc_byte_buffer* c_buffer() { return buffer_; }
+  grpc_byte_buffer** c_buffer_ptr() { return &buffer_; }
+
+  // DEPRECATED: Implicit conversion to transparently
+  // support deprecated SerializationTraits API
+  // No need to inline since deprecated
+  operator grpc_byte_buffer*();
+  operator const grpc_byte_buffer*() const;
+
+  grpc_byte_buffer* buffer_;
+};
+
+template <>
+class SerializationTraits<ByteBuffer, void> {
+ public:
+  static Status Deserialize(const ByteBuffer& byte_buffer, ByteBuffer* dest) {
+    dest->set_buffer(byte_buffer.buffer_);
+    return Status::OK;
+  }
+  static Status Serialize(const ByteBuffer& source, ByteBuffer* buffer,
+                          bool* own_buffer) {
+    *buffer = source;
+    *own_buffer = true;
+    return Status::OK;
+  }
+};
+
+}  // namespace grpc
+
+#endif  // GRPCXX_IMPL_CODEGEN_BYTE_BUFFER_H
diff --git a/include/grpc++/impl/codegen/call.h b/include/grpc++/impl/codegen/call.h
index 74ed5cbfb9..3c418c7ae2 100644
--- a/include/grpc++/impl/codegen/call.h
+++ b/include/grpc++/impl/codegen/call.h
@@ -25,6 +25,7 @@
 #include <map>
 #include <memory>
 
+#include <grpc++/impl/codegen/byte_buffer.h>
 #include <grpc++/impl/codegen/call_hook.h>
 #include <grpc++/impl/codegen/client_context.h>
 #include <grpc++/impl/codegen/completion_queue_tag.h>
@@ -39,8 +40,6 @@
 #include <grpc/impl/codegen/compression_types.h>
 #include <grpc/impl/codegen/grpc_types.h>
 
-struct grpc_byte_buffer;
-
 namespace grpc {
 
 class ByteBuffer;
@@ -281,7 +280,7 @@ class CallOpSendInitialMetadata {
 
 class CallOpSendMessage {
  public:
-  CallOpSendMessage() : send_buf_(nullptr) {}
+  CallOpSendMessage() : send_buf_() {}
 
   /// Send \a message using \a options for the write. The \a options are cleared
   /// after use.
@@ -294,33 +293,67 @@ class CallOpSendMessage {
 
  protected:
   void AddOp(grpc_op* ops, size_t* nops) {
-    if (send_buf_ == nullptr) return;
+    if (!send_buf_.Valid()) return;
     grpc_op* op = &ops[(*nops)++];
     op->op = GRPC_OP_SEND_MESSAGE;
     op->flags = write_options_.flags();
     op->reserved = NULL;
-    op->data.send_message.send_message = send_buf_;
+    op->data.send_message.send_message = send_buf_.c_buffer();
     // Flags are per-message: clear them after use.
     write_options_.Clear();
   }
-  void FinishOp(bool* status) {
-    g_core_codegen_interface->grpc_byte_buffer_destroy(send_buf_);
-    send_buf_ = nullptr;
-  }
+  void FinishOp(bool* status) { send_buf_.Clear(); }
 
  private:
-  grpc_byte_buffer* send_buf_;
+  template <class M, class T = void>
+  class MessageSerializer;
+
+  ByteBuffer send_buf_;
   WriteOptions write_options_;
 };
 
+namespace internal {
+template <class T>
+T Example();
+}  // namespace internal
+
+template <class M>
+class CallOpSendMessage::MessageSerializer<
+    M, typename std::enable_if<std::is_same<
+           ::grpc::Status, decltype(SerializationTraits<M>::Serialize(
+                               internal::Example<const M&>(),
+                               internal::Example<grpc_byte_buffer**>(),
+                               internal::Example<bool*>()))>::value>::type> {
+ public:
+  static Status SendMessageInternal(const M& message, ByteBuffer* bbuf,
+                                    bool* own_buf) {
+    return SerializationTraits<M>::Serialize(message, bbuf->c_buffer_ptr(),
+                                             own_buf);
+  }
+};
+
+template <class M>
+class CallOpSendMessage::MessageSerializer<
+    M, typename std::enable_if<std::is_same<
+           ::grpc::Status, decltype(SerializationTraits<M>::Serialize(
+                               internal::Example<const M&>(),
+                               internal::Example<::grpc::ByteBuffer*>(),
+                               internal::Example<bool*>()))>::value>::type> {
+ public:
+  static Status SendMessageInternal(const M& message, ByteBuffer* bbuf,
+                                    bool* own_buf) {
+    return SerializationTraits<M>::Serialize(message, bbuf, own_buf);
+  }
+};
+
 template <class M>
 Status CallOpSendMessage::SendMessage(const M& message, WriteOptions options) {
   write_options_ = options;
   bool own_buf;
   Status result =
-      SerializationTraits<M>::Serialize(message, &send_buf_, &own_buf);
+      MessageSerializer<M>::SendMessageInternal(message, &send_buf_, &own_buf);
   if (!own_buf) {
-    send_buf_ = g_core_codegen_interface->grpc_byte_buffer_copy(send_buf_);
+    send_buf_.Duplicate();
   }
   return result;
 }
@@ -330,6 +363,36 @@ Status CallOpSendMessage::SendMessage(const M& message) {
   return SendMessage(message, WriteOptions());
 }
 
+namespace internal {
+template <class M, class T = void>
+class MessageDeserializer;
+
+template <class M>
+class MessageDeserializer<
+    M, typename std::enable_if<std::is_same<
+           ::grpc::Status, decltype(SerializationTraits<M>::Deserialize(
+                               internal::Example<const ::grpc::ByteBuffer&>(),
+                               internal::Example<M*>()))>::value>::type> {
+ public:
+  static Status Deserialize(const ByteBuffer& bbuf, M* message) {
+    return SerializationTraits<M>::Deserialize(bbuf, message);
+  }
+};
+
+template <class M>
+class MessageDeserializer<
+    M, typename std::enable_if<std::is_same<
+           ::grpc::Status, decltype(SerializationTraits<M>::Deserialize(
+                               internal::Example<grpc_byte_buffer*>(),
+                               internal::Example<M*>()))>::value>::type> {
+ public:
+  static Status Deserialize(const ByteBuffer& bbuf, M* message) {
+    return SerializationTraits<M>::Deserialize(
+        const_cast<ByteBuffer&>(bbuf).c_buffer(), message);
+  }
+};
+}  // namespace internal
+
 template <class R>
 class CallOpRecvMessage {
  public:
@@ -352,18 +415,20 @@ class CallOpRecvMessage {
     op->op = GRPC_OP_RECV_MESSAGE;
     op->flags = 0;
     op->reserved = NULL;
-    op->data.recv_message.recv_message = &recv_buf_;
+    op->data.recv_message.recv_message = recv_buf_.c_buffer_ptr();
   }
 
   void FinishOp(bool* status) {
     if (message_ == nullptr) return;
-    if (recv_buf_) {
+    if (recv_buf_.Valid()) {
       if (*status) {
         got_message = *status =
-            SerializationTraits<R>::Deserialize(recv_buf_, message_).ok();
+            internal::MessageDeserializer<R>::Deserialize(recv_buf_, message_)
+                .ok();
+        recv_buf_.Release();
       } else {
         got_message = false;
-        g_core_codegen_interface->grpc_byte_buffer_destroy(recv_buf_);
+        recv_buf_.Clear();
       }
     } else {
       got_message = false;
@@ -376,14 +441,14 @@ class CallOpRecvMessage {
 
  private:
   R* message_;
-  grpc_byte_buffer* recv_buf_;
+  ByteBuffer recv_buf_;
   bool allow_not_getting_message_;
 };
 
 namespace CallOpGenericRecvMessageHelper {
 class DeserializeFunc {
  public:
-  virtual Status Deserialize(grpc_byte_buffer* buf) = 0;
+  virtual Status Deserialize(const ByteBuffer& buf) = 0;
   virtual ~DeserializeFunc() {}
 };
 
@@ -391,8 +456,8 @@ template <class R>
 class DeserializeFuncType final : public DeserializeFunc {
  public:
   DeserializeFuncType(R* message) : message_(message) {}
-  Status Deserialize(grpc_byte_buffer* buf) override {
-    return SerializationTraits<R>::Deserialize(buf, message_);
+  Status Deserialize(const ByteBuffer& buf) override {
+    return grpc::internal::MessageDeserializer<R>::Deserialize(buf, message_);
   }
 
   ~DeserializeFuncType() override {}
@@ -428,18 +493,19 @@ class CallOpGenericRecvMessage {
     op->op = GRPC_OP_RECV_MESSAGE;
     op->flags = 0;
     op->reserved = NULL;
-    op->data.recv_message.recv_message = &recv_buf_;
+    op->data.recv_message.recv_message = recv_buf_.c_buffer_ptr();
   }
 
   void FinishOp(bool* status) {
     if (!deserialize_) return;
-    if (recv_buf_) {
+    if (recv_buf_.Valid()) {
       if (*status) {
         got_message = true;
         *status = deserialize_->Deserialize(recv_buf_).ok();
+        recv_buf_.Release();
       } else {
         got_message = false;
-        g_core_codegen_interface->grpc_byte_buffer_destroy(recv_buf_);
+        recv_buf_.Clear();
       }
     } else {
       got_message = false;
@@ -452,7 +518,7 @@ class CallOpGenericRecvMessage {
 
  private:
   std::unique_ptr<CallOpGenericRecvMessageHelper::DeserializeFunc> deserialize_;
-  grpc_byte_buffer* recv_buf_;
+  ByteBuffer recv_buf_;
   bool allow_not_getting_message_;
 };
 
diff --git a/include/grpc++/impl/codegen/method_handler_impl.h b/include/grpc++/impl/codegen/method_handler_impl.h
index 15e24bdcdc..8125e0a651 100644
--- a/include/grpc++/impl/codegen/method_handler_impl.h
+++ b/include/grpc++/impl/codegen/method_handler_impl.h
@@ -19,6 +19,7 @@
 #ifndef GRPCXX_IMPL_CODEGEN_METHOD_HANDLER_IMPL_H
 #define GRPCXX_IMPL_CODEGEN_METHOD_HANDLER_IMPL_H
 
+#include <grpc++/impl/codegen/byte_buffer.h>
 #include <grpc++/impl/codegen/core_codegen_interface.h>
 #include <grpc++/impl/codegen/rpc_service_method.h>
 #include <grpc++/impl/codegen/sync_stream.h>
@@ -37,8 +38,8 @@ class RpcMethodHandler : public MethodHandler {
 
   void RunHandler(const HandlerParameter& param) final {
     RequestType req;
-    Status status =
-        SerializationTraits<RequestType>::Deserialize(param.request, &req);
+    Status status = internal::MessageDeserializer<RequestType>::Deserialize(
+        param.request, &req);
     ResponseType rsp;
     if (status.ok()) {
       status = func_(service_, param.server_context, &req, &rsp);
@@ -123,8 +124,8 @@ class ServerStreamingHandler : public MethodHandler {
 
   void RunHandler(const HandlerParameter& param) final {
     RequestType req;
-    Status status =
-        SerializationTraits<RequestType>::Deserialize(param.request, &req);
+    Status status = internal::MessageDeserializer<RequestType>::Deserialize(
+        param.request, &req);
 
     if (status.ok()) {
       ServerWriter<ResponseType> writer(param.call, param.server_context);
diff --git a/include/grpc++/impl/codegen/rpc_service_method.h b/include/grpc++/impl/codegen/rpc_service_method.h
index 7165774172..d356012ad6 100644
--- a/include/grpc++/impl/codegen/rpc_service_method.h
+++ b/include/grpc++/impl/codegen/rpc_service_method.h
@@ -25,14 +25,11 @@
 #include <memory>
 #include <vector>
 
+#include <grpc++/impl/codegen/byte_buffer.h>
 #include <grpc++/impl/codegen/config.h>
 #include <grpc++/impl/codegen/rpc_method.h>
 #include <grpc++/impl/codegen/status.h>
 
-extern "C" {
-struct grpc_byte_buffer;
-}
-
 namespace grpc {
 class ServerContext;
 class StreamContextInterface;
@@ -43,11 +40,14 @@ class MethodHandler {
   virtual ~MethodHandler() {}
   struct HandlerParameter {
     HandlerParameter(Call* c, ServerContext* context, grpc_byte_buffer* req)
-        : call(c), server_context(context), request(req) {}
+        : call(c), server_context(context) {
+      request.set_buffer(req);
+    }
+    ~HandlerParameter() { request.Release(); }
     Call* call;
     ServerContext* server_context;
-    // Handler required to grpc_byte_buffer_destroy this
-    grpc_byte_buffer* request;
+    // Handler required to destroy these contents
+    ByteBuffer request;
   };
   virtual void RunHandler(const HandlerParameter& param) = 0;
 };
diff --git a/include/grpc++/impl/codegen/serialization_traits.h b/include/grpc++/impl/codegen/serialization_traits.h
index b72d474126..7fc4e24172 100644
--- a/include/grpc++/impl/codegen/serialization_traits.h
+++ b/include/grpc++/impl/codegen/serialization_traits.h
@@ -26,15 +26,24 @@ namespace grpc {
 /// Used for hooking different message serialization API's into GRPC.
 /// Each SerializationTraits implementation must provide the following
 /// functions:
-///   static Status Serialize(const Message& msg,
-///                           grpc_byte_buffer** buffer,
-///                           bool* own_buffer);
-///   static Status Deserialize(grpc_byte_buffer* buffer,
-///                             Message* msg,
-///                             int max_receive_message_size);
+/// 1.  static Status Serialize(const Message& msg,
+///                             ByteBuffer* buffer,
+///                             bool* own_buffer);
+///     AND/OR
+///     static Status Serialize(const Message& msg,
+///                             grpc_byte_buffer** buffer,
+///                             bool* own_buffer);
+///     The former is preferred; the latter is deprecated
 ///
-/// Serialize is required to convert message to a grpc_byte_buffer, and
-/// to store a pointer to that byte buffer at *buffer. *own_buffer should
+/// 2.  static Status Deserialize(const ByteBuffer& buffer,
+///                               Message* msg);
+///     AND/OR
+///     static Status Deserialize(grpc_byte_buffer* buffer,
+///                               Message* msg);
+///     The former is preferred; the latter is deprecated
+///
+/// Serialize is required to convert message to a ByteBuffer, and
+/// return that byte buffer through *buffer. *own_buffer should
 /// be set to true if the caller owns said byte buffer, or false if
 /// ownership is retained elsewhere.
 ///
diff --git a/include/grpc++/impl/codegen/slice.h b/include/grpc++/impl/codegen/slice.h
index e682bdef6a..c185bf4fd0 100644
--- a/include/grpc++/impl/codegen/slice.h
+++ b/include/grpc++/impl/codegen/slice.h
@@ -19,11 +19,89 @@
 #ifndef GRPCXX_IMPL_CODEGEN_SLICE_H
 #define GRPCXX_IMPL_CODEGEN_SLICE_H
 
+#include <grpc++/impl/codegen/config.h>
 #include <grpc++/impl/codegen/core_codegen_interface.h>
 #include <grpc++/impl/codegen/string_ref.h>
 
+#include <grpc/impl/codegen/slice.h>
+
 namespace grpc {
 
+/// A wrapper around \a grpc_slice.
+///
+/// A slice represents a contiguous reference counted array of bytes.
+/// It is cheap to take references to a slice, and it is cheap to create a
+/// slice pointing to a subset of another slice.
+class Slice final {
+ public:
+  /// Construct an empty slice.
+  Slice();
+  /// Destructor - drops one reference.
+  ~Slice();
+
+  enum AddRef { ADD_REF };
+  /// Construct a slice from \a slice, adding a reference.
+  Slice(grpc_slice slice, AddRef);
+
+  enum StealRef { STEAL_REF };
+  /// Construct a slice from \a slice, stealing a reference.
+  Slice(grpc_slice slice, StealRef);
+
+  /// Allocate a slice of specified size
+  Slice(size_t len);
+
+  /// Construct a slice from a copied buffer
+  Slice(const void* buf, size_t len);
+
+  /// Construct a slice from a copied string
+  Slice(const grpc::string& str);
+
+  enum StaticSlice { STATIC_SLICE };
+
+  /// Construct a slice from a static buffer
+  Slice(const void* buf, size_t len, StaticSlice);
+
+  /// Copy constructor, adds a reference.
+  Slice(const Slice& other);
+
+  /// Assignment, reference count is unchanged.
+  Slice& operator=(Slice other) {
+    std::swap(slice_, other.slice_);
+    return *this;
+  }
+
+  /// Create a slice pointing at some data. Calls malloc to allocate a refcount
+  /// for the object, and arranges that destroy will be called with the
+  /// user data pointer passed in at destruction. Can be the same as buf or
+  /// different (e.g., if data is part of a larger structure that must be
+  /// destroyed when the data is no longer needed)
+  Slice(void* buf, size_t len, void (*destroy)(void*), void* user_data);
+
+  /// Specialization of above for common case where buf == user_data
+  Slice(void* buf, size_t len, void (*destroy)(void*))
+      : Slice(buf, len, destroy, buf) {}
+
+  /// Similar to the above but has a destroy that also takes slice length
+  Slice(void* buf, size_t len, void (*destroy)(void*, size_t));
+
+  /// Byte size.
+  size_t size() const { return GRPC_SLICE_LENGTH(slice_); }
+
+  /// Raw pointer to the beginning (first element) of the slice.
+  const uint8_t* begin() const { return GRPC_SLICE_START_PTR(slice_); }
+
+  /// Raw pointer to the end (one byte \em past the last element) of the slice.
+  const uint8_t* end() const { return GRPC_SLICE_END_PTR(slice_); }
+
+  /// Raw C slice. Caller needs to call grpc_slice_unref when done.
+  grpc_slice c_slice() const;
+
+ private:
+  friend class ByteBuffer;
+
+  grpc_slice slice_;
+};
+
 inline grpc::string_ref StringRefFromSlice(const grpc_slice* slice) {
   return grpc::string_ref(
       reinterpret_cast<const char*>(GRPC_SLICE_START_PTR(*slice)),
diff --git a/include/grpc++/support/byte_buffer.h b/include/grpc++/support/byte_buffer.h
index df16c6a75e..81fa3b0a18 100644
--- a/include/grpc++/support/byte_buffer.h
+++ b/include/grpc++/support/byte_buffer.h
@@ -19,6 +19,7 @@
 #ifndef GRPCXX_SUPPORT_BYTE_BUFFER_H
 #define GRPCXX_SUPPORT_BYTE_BUFFER_H
 
+#include <grpc++/impl/codegen/byte_buffer.h>
 #include <grpc++/impl/serialization_traits.h>
 #include <grpc++/support/config.h>
 #include <grpc++/support/slice.h>
@@ -27,71 +28,4 @@
 #include <grpc/grpc.h>
 #include <grpc/support/log.h>
 
-#include <vector>
-
-namespace grpc {
-
-/// A sequence of bytes.
-class ByteBuffer final {
- public:
-  /// Constuct an empty buffer.
-  ByteBuffer() : buffer_(nullptr) {}
-
-  /// Construct buffer from \a slices, of which there are \a nslices.
-  ByteBuffer(const Slice* slices, size_t nslices);
-
-  /// Constuct a byte buffer by referencing elements of existing buffer
-  /// \a buf. Wrapper of core function grpc_byte_buffer_copy
-  ByteBuffer(const ByteBuffer& buf);
-
-  ~ByteBuffer();
-
-  ByteBuffer& operator=(const ByteBuffer&);
-
-  /// Dump (read) the buffer contents into \a slices.
-  Status Dump(std::vector<Slice>* slices) const;
-
-  /// Remove all data.
-  void Clear();
-
-  /// Buffer size in bytes.
-  size_t Length() const;
-
-  /// Swap the state of *this and *other.
-  void Swap(ByteBuffer* other);
-
- private:
-  friend class SerializationTraits<ByteBuffer, void>;
-
-  // takes ownership
-  void set_buffer(grpc_byte_buffer* buf) {
-    if (buffer_) {
-      Clear();
-    }
-    buffer_ = buf;
-  }
-
-  // For \a SerializationTraits's usage.
-  grpc_byte_buffer* buffer() const { return buffer_; }
-
-  grpc_byte_buffer* buffer_;
-};
-
-template <>
-class SerializationTraits<ByteBuffer, void> {
- public:
-  static Status Deserialize(grpc_byte_buffer* byte_buffer, ByteBuffer* dest) {
-    dest->set_buffer(byte_buffer);
-    return Status::OK;
-  }
-  static Status Serialize(const ByteBuffer& source, grpc_byte_buffer** buffer,
-                          bool* own_buffer) {
-    *buffer = grpc_byte_buffer_copy(source.buffer());
-    *own_buffer = true;
-    return Status::OK;
-  }
-};
-
-}  // namespace grpc
-
 #endif  // GRPCXX_SUPPORT_BYTE_BUFFER_H
diff --git a/include/grpc++/support/slice.h b/include/grpc++/support/slice.h
index bbf97f280e..10db10d79c 100644
--- a/include/grpc++/support/slice.h
+++ b/include/grpc++/support/slice.h
@@ -19,86 +19,8 @@
 #ifndef GRPCXX_SUPPORT_SLICE_H
 #define GRPCXX_SUPPORT_SLICE_H
 
+#include <grpc++/impl/codegen/slice.h>
 #include <grpc++/support/config.h>
 #include <grpc/slice.h>
 
-namespace grpc {
-
-/// A wrapper around \a grpc_slice.
-///
-/// A slice represents a contiguous reference counted array of bytes.
-/// It is cheap to take references to a slice, and it is cheap to create a
-/// slice pointing to a subset of another slice.
-class Slice final {
- public:
-  /// Construct an empty slice.
-  Slice();
-  /// Destructor - drops one reference.
-  ~Slice();
-
-  enum AddRef { ADD_REF };
-  /// Construct a slice from \a slice, adding a reference.
-  Slice(grpc_slice slice, AddRef);
-
-  enum StealRef { STEAL_REF };
-  /// Construct a slice from \a slice, stealing a reference.
-  Slice(grpc_slice slice, StealRef);
-
-  /// Allocate a slice of specified size
-  Slice(size_t len);
-
-  /// Construct a slice from a copied buffer
-  Slice(const void* buf, size_t len);
-
-  /// Construct a slice from a copied string
-  Slice(const grpc::string& str);
-
-  enum StaticSlice { STATIC_SLICE };
-
-  /// Construct a slice from a static buffer
-  Slice(const void* buf, size_t len, StaticSlice);
-
-  /// Copy constructor, adds a reference.
-  Slice(const Slice& other);
-
-  /// Assignment, reference count is unchanged.
-  Slice& operator=(Slice other) {
-    std::swap(slice_, other.slice_);
-    return *this;
-  }
-
-  /// Create a slice pointing at some data. Calls malloc to allocate a refcount
-  /// for the object, and arranges that destroy will be called with the
-  /// user data pointer passed in at destruction. Can be the same as buf or
-  /// different (e.g., if data is part of a larger structure that must be
-  /// destroyed when the data is no longer needed)
-  Slice(void* buf, size_t len, void (*destroy)(void*), void* user_data);
-
-  /// Specialization of above for common case where buf == user_data
-  Slice(void* buf, size_t len, void (*destroy)(void*))
-      : Slice(buf, len, destroy, buf) {}
-
-  /// Similar to the above but has a destroy that also takes slice length
-  Slice(void* buf, size_t len, void (*destroy)(void*, size_t));
-
-  /// Byte size.
-  size_t size() const { return GRPC_SLICE_LENGTH(slice_); }
-
-  /// Raw pointer to the beginning (first element) of the slice.
-  const uint8_t* begin() const { return GRPC_SLICE_START_PTR(slice_); }
-
-  /// Raw pointer to the end (one byte \em past the last element) of the slice.
-  const uint8_t* end() const { return GRPC_SLICE_END_PTR(slice_); }
-
-  /// Raw C slice. Caller needs to call grpc_slice_unref when done.
-  grpc_slice c_slice() const { return grpc_slice_ref(slice_); }
-
- private:
-  friend class ByteBuffer;
-
-  grpc_slice slice_;
-};
-
-}  // namespace grpc
-
 #endif  // GRPCXX_SUPPORT_SLICE_H