`omnetpp-cmake` — CMake + OMNeT++ = ❤

This repository is a community-supported work-in-progress, and may never be fully completed. Please help us and others like you by contributing. Thanks!

CMake Modules for building OMNeT++ projects and integrating with you CMake supporting editor.

These CMake modules were originally developed against OMNeT+ 5.X, but should also work with OMNeT++ 6.0 and beyond.

We are currently building our 📝 documentation website at https://omnetpp.github.io/cmake. Though this documentation is still work-in-progress, you may already have a look at it!

Usage

The following is one of many other ways to do it.

Add the repository as a git submodule to your repository in cmake.¹
```
git submodule add https://github.com/omnetpp/cmake.git cmake
```
⚠ Note: If you have other CMake modules it is recommended that you replace cmake with cmake/omnet and so forth here and in the following steps.
Update and/or initialise the submodule.¹
```
git submodule update --init --recursive
```

Create a minimal CMakeLists.txt in the root repository folder.

project(YourProject)

# It is recommended to increase the minimum version to your current
cmake_minimum_required(VERSION 3.1)

# Change "cmake" if you put the submodule in a different directory
set(CMAKE_MODULE_PATH ${PROJECT_SOURCE_DIR}/cmake)

find_package(OmnetPP 6.0 REQUIRED)

# Load the CMake commands for OMNeT++
include(OmnetppHelpers)

Update your CMakeLists.txt with your OMNeT++ project details

# Uncomment the following if you have external dependencies like INET
#find_path(INET_DIR NAMES src/inet/package.ned DOC "INET root directory")
#import_opp_target(inet ${INET_DIR}/src/Makefile)

# Define your library/simulation sources
set(SOURCES
    src/a.cc
    src/b.cc)

add_library(project_library SHARED ${SOURCES})

# Define your messages as well
set(MESSAGE_SOURCES
    messages/a.msg
    messages/b.msg)

generate_opp_message(project_library
    MESSAGE_FILES ${MESSAGE_SOURCES})

# You will need to tweak and add the additional properties for your project
set_target_properties(project_library PROPERTIES
    OUTPUT_NAME my_project_sim
    NED_FOLDERS src)

# Link the libraries you need for your project; add "inet" if necessary
target_link_libraries(project_library opp_interface)

# This creates an OMNet++ CMake run for you
add_opp_run(project_name 
    CONFIG omnetpp.ini 
    DEPENDENCY project_library)

Macros Available

generate_opp_message(<target> MESSAGE_FILES <file1> ...)
Generates and links a message file to a given target.
import_opp_target(<opp_makemake_target> <Makefile> [ <cmake_target_file> ])
Imports a target from a Makefile created by opp_makemake.
⚠ Note: The target must have the same name as in the Makefile!
add_opp_build_target(<name>)
Adds a build target with a given name.
add_opp_run(<name> [ CONFIG <file> | WORKING_DIRECTORY <dir> | NED_FOLDERS <dir1> ... ] DEPENDENCY <target> )
Adds a build target with a given name based on the given dependency.
add_opp_test(<name> [CONFIG <file> | RUN <entry> | SIMTIME_LIMIT <limit> | SUFFIX <name>]) Adds a test target with a given name.

Interfaces and Library Targets Available

OmnetPP::header is a bare interface target with at least the compile definitions and include directories set for the found OMNeT++ setup. Additionally, the following OMNeT++ libraries are provided as imported library targets:

OmnetPP::cmdenv
OmnetPP::common
OmnetPP::envir
OmnetPP::eventlog
OmnetPP::layout
OmnetPP::main
OmnetPP::nedxml
OmnetPP::qtenv
OmnetPP::qtenv-osg
OmnetPP::scave
OmnetPP::sim
OmnetPP::tkenv

Motivation & Background

For the full motivation and background please see Raphael Riebl's presentation at the 2015 OMNeT++ Summit.

Some benefits include:

CMake is widely used for C/C++ projects
Convenient user interfaces available for configuring builds
Solid dependency handling, both internal and external
More accessible syntax compared to Makefiles
Several IDEs support the CMake build system
Support OMNeT++ 6.0 preview releases (by @thor)

Caveats

There have been some changes which might require fixes or future improvements. These are primarily changes to make the proof-of-concept employed in Artery also work with OMNet++ 6.0. However, there are also some minor oddities and questions, uncertainties and the likes of which.

opp_cmake.py will not take a lot of automatic definitions into account when importing a project
clean_opp_messages() is unavailable as message files are no longer gathered in a single folder for buliding
include path needs to be adjusted manually if #include "generated_m.h" is used
add_opp_run doesn't seem to utilise the parameter NED_FOLDERS

Licensing

The CMake modules were based on those in the OMNet++ V2X simulation framework in riebl/artery, which is licensed as GPL-2.0.

References

1: You could also just download the files and put them where you'd like, or if you want to contribute, fork it and add that repository as a submodule! ↩

2: You may exchange the paths as you wish, but make sure to update them later on too. ↩