C++17 Extension

This extension implements a C++17 generator for Zserio.

Motivation

Zserio already provides a C++ generator which uses the C++11 standard.

The user experience with the current C++ generator has led to new ideas and enhancements that could improve the usability of the generated code. Additionally, as time flies, users have requested support for the more modern C++17 standard. However, such changes to the generated code would break backward compatibility with existing user applications, which is undesirable. Therefore, this brand new C++17 generator with an incompatible API has been developed.

Advantages

The following two main features of a C++17 generator offer significant advantages over the current C++ generator:

• Implementation of the Parameterized Types

  New C++17 generator implements Zserio Structures, Choices, and Unions using a new Data View abstraction. This new abstraction naturally solves tge implementation of Parameterized Types without the need for two-phase initialization or custom copy and move constructors.

• Implementation of the Templates

  New C++17 generator implements Zserio templates using C++ native templates. To distinguish which Zserio native type is used as a template argument (e.g. Zserio bit:5 and bit:7 types are stored in the same C++ uint8_t type), this approach also involves implementing dedicated C++ Zserio types for all Zserio built-in types within the C++ runtime library.

Supported Platforms

Zserio C++17 generator supports the following platforms:

• 64-bit Linux
• 32-bit Linux
• 64-bit Windows

Supported Compilers

Zserio C++17 generator supports the following C++ compilers:

• g++ 11.4.0
• clang 14.0.0
• clang 18.1.3
• MinGW 11.2.0
• MSVC 2022

Although newer C++ compilers are not tested, they should work as well as long as they are backward compatible.

Current State

The Design Document acts as the primary source of information about the C++17 generator design and is updated regularly.

Current state (10.12.2024):

• The generator fully supports the following Zserio types:
  • Enumeration types
  • Bitmask types
  • Constants
  • Structure types
  • Choice types
  • Union types
• Extended members are not implemented and are always generated as regular compound fields
• Templates are generated as instantiations without usage of native C++ templates
• Offsets, Service Types, Pubsub Types, SQL databases and SQL tables are silently ignored
• No support for generic programming, including JSON export and import

How to Get the latest C++17 Generator

Download the latest Zserio bundle jar (together with Zserio runtime library) from the GitHub action artifacts using the following steps:

• Go to the Actions page
• Click on the latest Linux workflow
• Scroll down to the Artifacts
• Download zserio-java8 artifact for Zserio bundle jar
• Alternatively, download zserio-runtime-cpp artifact for Zserio runtime library

How to Run the latest C++17 Generator

Run the Zserio C++17 generator using the following steps:

• Unzip zserio-java8 to get zserio.jar binary
• Run the command java -jar zserio.jar schema_name.zs -cpp17 output_directory_name