Function CalculateDynamicDescriptorSize

engine/ddf/src/ddf/ddf.cpp:102–169

    }

    static Result CalculateDynamicDescriptorSize(LoadContext* load_context, InputBuffer* ib, const Descriptor* desc, bool is_dynamic_type)
    {
        while (!ib->Eof())
        {
            uint32_t tag;
            if (!ib->ReadVarInt32(&tag))
                return RESULT_WIRE_FORMAT_ERROR;

            uint32_t key  = tag >> 3;
            uint32_t type = tag & 0x7;

            if (key == 0)
                return RESULT_WIRE_FORMAT_ERROR;

            const FieldDescriptor* field = FindField(desc, key, 0);
            if (!field)
            {
                // Unknown field, just skip
                Result e = SkipField(ib, type);
                DDF_CHECK_RESULT(e);
                continue;
            }

            if (field->m_Type == TYPE_MESSAGE)
            {
                // All submessages are length-delimited
                uint32_t length;
                if (!ib->ReadVarInt32(&length))
                    return RESULT_WIRE_FORMAT_ERROR;

                // Create a view of just this submessage's bytes
                InputBuffer sub_ib;
                if (!ib->SubBuffer(length, &sub_ib))
                    return RESULT_WIRE_FORMAT_ERROR;

                is_dynamic_type = is_dynamic_type || !field->m_FullyDefinedType;
                if (is_dynamic_type)
                {
                    // We need to account for the injected oneof index value that we insert into the structs via ddfc.py!
                    uint32_t dynamic_size = field->m_MessageDescriptor->m_Size;
                    if (field->m_OneOfIndex != DDF_NO_ONE_OF_INDEX)
                    {
                        dynamic_size += sizeof(uint32_t);
                    }

                    load_context->AddDynamicMessageSize(dynamic_size);
                }

                // Recurse into the submessage descriptor
                Result e = CalculateDynamicDescriptorSize(load_context, &sub_ib, field->m_MessageDescriptor, is_dynamic_type);
                DDF_CHECK_RESULT(e);

                // Ensure the sub-buffer is fully consumed
                if (!sub_ib.Eof())
                {
                    return RESULT_WIRE_FORMAT_ERROR;
                }
            }