Support of external members (#170)

* Refs #19697. External template and api tests

Signed-off-by: Ricardo González Moreno <ricardo@richiware.dev>

* Refs #19697. Encode/decode external

Signed-off-by: Ricardo González Moreno <ricardo@richiware.dev>

* Refs #19697. Apply suggestions

Signed-off-by: Ricardo González Moreno <ricardo@richiware.dev>

---------

Signed-off-by: Ricardo González Moreno <ricardo@richiware.dev>

include/fastcdr/Cdr.h

@@ -35,6 +35,7 @@
 #include "exceptions/Exception.h"
 #include "exceptions/NotEnoughMemoryException.h"
 #include "FastBuffer.h"
+#include "xcdr/external.hpp"
 #include "xcdr/MemberId.hpp"
 #include "xcdr/optional.hpp"
 
@@ -2676,6 +2677,27 @@ class Cdr
         return *this;
     }
 
+    /*!
+     * @brief Encodes an external in the buffer.
+     * @param[in] value A reference to the external which will be encoded in the buffer.
+     * @return Reference to the eprosima::fastcdr::Cdr object.
+     * @exception exception::BadParamException This exception is thrown when external is null.
+     * @exception exception::NotEnoughMemoryException This exception is thrown when trying to encode into a buffer
+     * position that exceeds the internal memory size.
+     */
+    template<class _T>
+    Cdr& serialize(
+            const external<_T>& value)
+    {
+        if (!value)
+        {
+            throw exception::BadParamException("External member is null");
+        }
+
+        serialize(*value);
+        return *this;
+    }
+
     /*!
      * @brief Tells the encoder the member identifier for the next member to be encoded.
      * @param[in] member_id Member identifier.
@@ -2719,6 +2741,62 @@ class Cdr
         return *this;
     }
 
+    /*!
+     * @brief Decodes an external from the buffer.
+     * @param[out] value A reference to the variable where the external will be stored.
+     * @return Reference to the eprosima::fastcdr::Cdr object.
+     * @exception exception::BadParamException This exception is thrown when the external is locked.
+     * @exception exception::NotEnoughMemoryException This exception is thrown when trying to decode from a buffer
+     * position that exceeds the internal memory size.
+     */
+    template<class _T>
+    Cdr& deserialize(
+            external<_T>& value)
+    {
+        if (value.is_locked())
+        {
+            throw exception::BadParamException("External member is locked");
+        }
+
+        if (!value)
+        {
+            value = external<_T>{new _T()};
+        }
+
+        deserialize(*value);
+        return *this;
+    }
+
+    /*!
+     * @brief Decodes an optional of an external from the buffer.
+     * @param[out] value A reference to the variable where the optional will be stored.
+     * @return Reference to the eprosima::fastcdr::Cdr object.
+     * @exception exception::BadParamException This exception is thrown when the external is locked.
+     * @exception exception::NotEnoughMemoryException This exception is thrown when trying to decode from a buffer
+     * position that exceeds the internal memory size.
+     */
+    template<class _T>
+    Cdr& deserialize(
+            optional<external<_T>>& value)
+    {
+        if (value.has_value() && value.value().is_locked())
+        {
+            throw exception::BadParamException("External member is locked");
+        }
+
+        bool is_present = true;
+        if (CdrVersion::XCDRv2 == cdr_version_ && EncodingAlgorithmFlag::PL_CDR2 != current_encoding_)
+        {
+            deserialize(is_present);
+        }
+        value.reset(is_present);
+        if (is_present)
+        {
+            deserialize(*value);
+        }
+        return *this;
+    }
+
 private:
 
     Cdr(

include/fastcdr/CdrSizeCalculator.hpp

@@ -27,6 +27,8 @@
 #include "CdrEncoding.hpp"
 #include "cdr/fixed_size_string.hpp"
 #include "detail/container_recursive_inspector.hpp"
+#include "exceptions/BadParamException.h"
+#include "xcdr/external.hpp"
 #include "xcdr/MemberId.hpp"
 #include "xcdr/optional.hpp"
 
@@ -751,6 +753,26 @@ class CdrSizeCalculator
         return calculated_size;
     }
 
+    /*!
+     * @brief Specific template which calculates the encoded size of an instance of an external type.
+     * @param[in] data Reference to the instance.
+     * @param[inout] current_alignment Current alignment in the encoding.
+     * @exception exception::BadParamException This exception is thrown when the external is null.
+     * @return Encoded size of the instance.
+     */
+    template<class _T>
+    size_t calculate_serialized_size(
+            const external<_T>& data,
+            size_t& current_alignment)
+    {
+        if (!data)
+        {
+            throw exception::BadParamException("External member is null");
+        }
+
+        return calculate_serialized_size(*data, current_alignment);
+    }
+
     /*!
      * @brief Specific template which calculates the encoded size of an instance of an array of unknown type.
      * @tparam _T Array's type.

include/fastcdr/exceptions/LockedExternalAccessException.hpp

@@ -0,0 +1,83 @@
+// Copyright 2023 Proyectos y Sistemas de Mantenimiento SL (eProsima).
+//
+// 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 _FASTCDR_EXCEPTIONS_LOCKEDEXTERNALACCESSEXCEPTION_H_
+#define _FASTCDR_EXCEPTIONS_LOCKEDEXTERNALACCESSEXCEPTION_H_
+
+#include "Exception.h"
+
+namespace eprosima {
+namespace fastcdr {
+namespace exception {
+/*!
+ * @brief This class is thrown as an exception when accessing to set the value of a locked external.
+ * @ingroup EXCEPTIONMODULE
+ */
+class LockedExternalAccessException : public Exception
+{
+public:
+
+    /*!
+     * @brief Default constructor.
+     *
+     * @param message An error message. This message pointer is copied.
+     */
+    Cdr_DllAPI LockedExternalAccessException(
+            const char* const& message) noexcept;
+
+    /*!
+     * @brief Default copy constructor.
+     *
+     * @param ex LockedExternalAccessException that will be copied.
+     */
+    Cdr_DllAPI LockedExternalAccessException(
+            const LockedExternalAccessException& ex) noexcept;
+
+    /*!
+     * @brief Default move constructor.
+     *
+     * @param ex LockedExternalAccessException that will be moved.
+     */
+    Cdr_DllAPI LockedExternalAccessException(
+            LockedExternalAccessException&& ex) noexcept;
+
+    /*!
+     * @brief Assigment operation.
+     *
+     * @param ex LockedExternalAccessException that will be copied.
+     */
+    Cdr_DllAPI LockedExternalAccessException& operator =(
+            const LockedExternalAccessException& ex) noexcept;
+
+    /*!
+     * @brief Assigment operation.
+     *
+     * @param ex LockedExternalAccessException that will be moved.
+     */
+    LockedExternalAccessException& operator =(
+            LockedExternalAccessException&& ex) noexcept;
+
+    //! @brief Default destructor
+    virtual Cdr_DllAPI ~LockedExternalAccessException() noexcept;
+
+    //! @brief This function throws the object as exception.
+    Cdr_DllAPI void raise() const override;
+
+    //! @brief Default message used in the library.
+    static Cdr_DllAPI const char* const LOCKED_EXTERNAL_ACCESS_MESSAGE_DEFAULT;
+};
+}         //namespace exception
+}     //namespace fastcdr
+} //namespace eprosima
+#endif // _FASTCDR_EXCEPTIONS_LOCKEDEXTERNALACCESSEXCEPTION_H_