Fix build warning in Ubuntu Focal (#346)

* Avoid using memcpy when writing to an object with non-trivial copy-assignment

Signed-off-by: Ivan Santiago Paunovic <ivanpauno@ekumenlabs.com>

rmw_fastrtps_cpp/src/rmw_publisher.cpp

@@ -20,6 +20,7 @@
 
 #include "rmw_fastrtps_shared_cpp/custom_participant_info.hpp"
 #include "rmw_fastrtps_shared_cpp/custom_publisher_info.hpp"
+#include "rmw_fastrtps_shared_cpp/guid_utils.hpp"
 #include "rmw_fastrtps_shared_cpp/names.hpp"
 #include "rmw_fastrtps_shared_cpp/namespace_prefix.hpp"
 #include "rmw_fastrtps_shared_cpp/qos.hpp"
@@ -117,7 +118,6 @@ rmw_create_publisher(
   CustomPublisherInfo * info = nullptr;
   rmw_publisher_t * rmw_publisher = nullptr;
   eprosima::fastrtps::PublisherAttributes publisherParam;
-  const eprosima::fastrtps::rtps::GUID_t * guid = nullptr;
 
   if (!is_valid_qos(*qos_policies)) {
     return nullptr;
@@ -193,12 +193,9 @@ rmw_create_publisher(
   );
 
   memset(info->publisher_gid.data, 0, RMW_GID_STORAGE_SIZE);
-  guid = &info->publisher_->getGuid();
-  if (!guid) {
-    RMW_SET_ERROR_MSG("no guid found for publisher");
-    goto fail;
-  }
-  memcpy(info->publisher_gid.data, guid, sizeof(eprosima::fastrtps::rtps::GUID_t));
+  rmw_fastrtps_shared_cpp::copy_from_fastrtps_guid_to_byte_array(
+    info->publisher_->getGuid(),
+    info->publisher_gid.data);
 
   rmw_publisher = rmw_publisher_allocate();
   if (!rmw_publisher) {

rmw_fastrtps_dynamic_cpp/src/rmw_publisher.cpp

@@ -20,6 +20,7 @@
 
 #include "rmw_fastrtps_shared_cpp/custom_participant_info.hpp"
 #include "rmw_fastrtps_shared_cpp/custom_publisher_info.hpp"
+#include "rmw_fastrtps_shared_cpp/guid_utils.hpp"
 #include "rmw_fastrtps_shared_cpp/names.hpp"
 #include "rmw_fastrtps_shared_cpp/namespace_prefix.hpp"
 #include "rmw_fastrtps_shared_cpp/qos.hpp"
@@ -121,7 +122,6 @@ rmw_create_publisher(
   CustomPublisherInfo * info = nullptr;
   rmw_publisher_t * rmw_publisher = nullptr;
   eprosima::fastrtps::PublisherAttributes publisherParam;
-  const eprosima::fastrtps::rtps::GUID_t * guid = nullptr;
 
   // Load default XML profile.
   Domain::getDefaultPublisherAttributes(publisherParam);
@@ -188,12 +188,9 @@ rmw_create_publisher(
   );
 
   memset(info->publisher_gid.data, 0, RMW_GID_STORAGE_SIZE);
-  guid = &info->publisher_->getGuid();
-  if (!guid) {
-    RMW_SET_ERROR_MSG("no guid found for publisher");
-    goto fail;
-  }
-  memcpy(info->publisher_gid.data, guid, sizeof(eprosima::fastrtps::rtps::GUID_t));
+  rmw_fastrtps_shared_cpp::copy_from_fastrtps_guid_to_byte_array(
+    info->publisher_->getGuid(),
+    info->publisher_gid.data);
 
   rmw_publisher = rmw_publisher_allocate();
   if (!rmw_publisher) {

rmw_fastrtps_shared_cpp/include/rmw_fastrtps_shared_cpp/guid_utils.hpp

@@ -0,0 +1,60 @@
+// Copyright 2020 Open Source Robotics Foundation, Inc.
+//
+// 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 RMW_FASTRTPS_SHARED_CPP__GUID_UTILS_HPP_
+#define RMW_FASTRTPS_SHARED_CPP__GUID_UTILS_HPP_
+
+#include <cassert>
+#include <cstring>
+#include <type_traits>
+
+#include "fastrtps/rtps/common/Guid.h"
+
+namespace rmw_fastrtps_shared_cpp
+{
+
+template<typename ByteT>
+void
+copy_from_byte_array_to_fastrtps_guid(
+  const ByteT * guid_byte_array,
+  eprosima::fastrtps::rtps::GUID_t * guid)
+{
+  static_assert(
+    std::is_same<uint8_t, ByteT>::value || std::is_same<int8_t, ByteT>::value,
+    "ByteT should be either int8_t or uint8_t");
+  assert(guid_byte_array);
+  assert(guid);
+  constexpr auto prefix_size = sizeof(guid->guidPrefix.value);
+  memcpy(guid->guidPrefix.value, guid_byte_array, prefix_size);
+  memcpy(guid->entityId.value, &guid_byte_array[prefix_size], guid->entityId.size);
+}
+
+template<typename ByteT>
+void
+copy_from_fastrtps_guid_to_byte_array(
+  const eprosima::fastrtps::rtps::GUID_t & guid,
+  ByteT * guid_byte_array)
+{
+  static_assert(
+    std::is_same<uint8_t, ByteT>::value || std::is_same<int8_t, ByteT>::value,
+    "ByteT should be either int8_t or uint8_t");
+  assert(guid_byte_array);
+  constexpr auto prefix_size = sizeof(guid.guidPrefix.value);
+  memcpy(guid_byte_array, &guid.guidPrefix, prefix_size);
+  memcpy(&guid_byte_array[prefix_size], &guid.entityId, guid.entityId.size);
+}
+
+}  // namespace rmw_fastrtps_shared_cpp
+
+#endif  // RMW_FASTRTPS_SHARED_CPP__GUID_UTILS_HPP_

rmw_fastrtps_shared_cpp/src/rmw_get_topic_endpoint_info.cpp

@@ -23,11 +23,13 @@
 #include "rmw/topic_endpoint_info_array.h"
 #include "rmw/topic_endpoint_info.h"
 
-#include "demangle.hpp"
 #include "rmw_fastrtps_shared_cpp/custom_participant_info.hpp"
+#include "rmw_fastrtps_shared_cpp/guid_utils.hpp"
 #include "rmw_fastrtps_shared_cpp/namespace_prefix.hpp"
 #include "rmw_fastrtps_shared_cpp/rmw_common.hpp"
 
+#include "demangle.hpp"
+
 namespace rmw_fastrtps_shared_cpp
 {
 
@@ -143,9 +145,10 @@ _set_rmw_topic_endpoint_info(
     return ret;
   }
   // set endpoint gid
-  uint8_t rmw_gid[RMW_GID_STORAGE_SIZE];
-  memset(&rmw_gid, 0, RMW_GID_STORAGE_SIZE);
-  memcpy(&rmw_gid, &topic_data.entity_guid, sizeof(eprosima::fastrtps::rtps::GUID_t));
+  uint8_t rmw_gid[RMW_GID_STORAGE_SIZE] = {};
+  rmw_fastrtps_shared_cpp::copy_from_fastrtps_guid_to_byte_array(
+    topic_data.entity_guid,
+    rmw_gid);
   ret = rmw_topic_endpoint_info_set_gid(
     topic_endpoint_info,
     rmw_gid,

rmw_fastrtps_shared_cpp/src/rmw_request.cpp

@@ -23,9 +23,10 @@
 #include "rmw/rmw.h"
 #include "rmw/types.h"
 
-#include "rmw_fastrtps_shared_cpp/rmw_common.hpp"
 #include "rmw_fastrtps_shared_cpp/custom_client_info.hpp"
 #include "rmw_fastrtps_shared_cpp/custom_service_info.hpp"
+#include "rmw_fastrtps_shared_cpp/guid_utils.hpp"
+#include "rmw_fastrtps_shared_cpp/rmw_common.hpp"
 #include "rmw_fastrtps_shared_cpp/TypeSupport.hpp"
 
 namespace rmw_fastrtps_shared_cpp
@@ -99,9 +100,9 @@ __rmw_take_request(
       deser, ros_request, info->request_type_support_impl_);
 
     // Get header
-    memcpy(
-      request_header->writer_guid, &request.sample_identity_.writer_guid(),
-      sizeof(eprosima::fastrtps::rtps::GUID_t));
+    rmw_fastrtps_shared_cpp::copy_from_fastrtps_guid_to_byte_array(
+      request.sample_identity_.writer_guid(),
+      request_header->writer_guid);
     request_header->sequence_number = ((int64_t)request.sample_identity_.sequence_number().high) <<
       32 | request.sample_identity_.sequence_number().low;
 

rmw_fastrtps_shared_cpp/src/rmw_response.cpp

@@ -21,9 +21,10 @@
 #include "rmw/error_handling.h"
 #include "rmw/rmw.h"
 
-#include "rmw_fastrtps_shared_cpp/rmw_common.hpp"
 #include "rmw_fastrtps_shared_cpp/custom_client_info.hpp"
 #include "rmw_fastrtps_shared_cpp/custom_service_info.hpp"
+#include "rmw_fastrtps_shared_cpp/guid_utils.hpp"
+#include "rmw_fastrtps_shared_cpp/rmw_common.hpp"
 #include "rmw_fastrtps_shared_cpp/TypeSupport.hpp"
 
 namespace rmw_fastrtps_shared_cpp
@@ -92,9 +93,9 @@ __rmw_send_response(
   assert(info);
 
   eprosima::fastrtps::rtps::WriteParams wparams;
-  memcpy(
-    &wparams.related_sample_identity().writer_guid(), request_header->writer_guid,
-    sizeof(eprosima::fastrtps::rtps::GUID_t));
+  rmw_fastrtps_shared_cpp::copy_from_byte_array_to_fastrtps_guid(
+    request_header->writer_guid,
+    &wparams.related_sample_identity().writer_guid());
   wparams.related_sample_identity().sequence_number().high =
     (int32_t)((request_header->sequence_number & 0xFFFFFFFF00000000) >> 32);
   wparams.related_sample_identity().sequence_number().low =

rmw_fastrtps_shared_cpp/src/rmw_take.cpp

@@ -24,8 +24,9 @@
 #include "fastcdr/Cdr.h"
 #include "fastcdr/FastBuffer.h"
 
-#include "rmw_fastrtps_shared_cpp/rmw_common.hpp"
 #include "rmw_fastrtps_shared_cpp/custom_subscriber_info.hpp"
+#include "rmw_fastrtps_shared_cpp/guid_utils.hpp"
+#include "rmw_fastrtps_shared_cpp/rmw_common.hpp"
 #include "rmw_fastrtps_shared_cpp/TypeSupport.hpp"
 
 namespace rmw_fastrtps_shared_cpp
@@ -39,9 +40,10 @@ _assign_message_info(
   rmw_gid_t * sender_gid = &message_info->publisher_gid;
   sender_gid->implementation_identifier = identifier;
   memset(sender_gid->data, 0, RMW_GID_STORAGE_SIZE);
-  memcpy(
-    sender_gid->data, &sinfo->sample_identity.writer_guid(),
-    sizeof(eprosima::fastrtps::rtps::GUID_t));
+
+  rmw_fastrtps_shared_cpp::copy_from_fastrtps_guid_to_byte_array(
+    sinfo->sample_identity.writer_guid(),
+    sender_gid->data);
 }
 
 rmw_ret_t