3. Linux installation from sources¶

The instructions for installing both the Fast DDS library and the Fast DDS-Gen generation tool from sources are provided in this page. It is organized as follows:

Fast DDS library installation
Fast DDS-Gen installation
- Requirements
- Compiling Fast DDS-Gen

3.1. Fast DDS library installation¶

This section describes the instructions for installing eProsima Fast DDS in a Linux environment from sources. The following packages will be installed:

foonathan_memory_vendor, an STL compatible C++ memory allocator library.
fastcdr, a C++ library that serializes according to the standard CDR serialization mechanism.
fastrtps, the core library of eProsima Fast DDS library.

First of all, the Requirements and Dependencies detailed below need to be met. Afterwards, the user can choose whether to follow either the colcon) or the CMake) installation instructions.

3.1.1. Requirements¶

The installation of eProsima Fast DDS in a Linux environment from sources requires the following tools to be installed in the system:

CMake, g++, pip3, wget and git
Gtest [optional]

3.1.1.1. CMake, g++, pip3, wget and git¶

These packages provide the tools required to install eProsima Fast DDS and its dependencies from command line. Install CMake, g++, pip3, wget and git using the package manager of the appropriate Linux distribution. For example, on Ubuntu use the command:

sudo apt install cmake g++ python3-pip wget git

3.1.1.2. Gtest¶

GTest is a unit testing library for C++. By default, eProsima Fast DDS does not compile tests. It is possible to activate them with the opportune CMake configuration options when calling colcon or CMake. For more details, please refer to the CMake options section. For a detailed description of the Gtest installation process, please refer to the Gtest Installation Guide.

3.1.2. Dependencies¶

eProsima Fast DDS has the following dependencies, when installed from binaries in a Linux environment:

Asio and TinyXML2 libraries
OpenSSL

3.1.2.1. Asio and TinyXML2 libraries¶

Asio is a cross-platform C++ library for network and low-level I/O programming, which provides a consistent asynchronous model. TinyXML2 is a simple, small and efficient C++ XML parser. Install these libraries using the package manager of the appropriate Linux distribution. For example, on Ubuntu use the command:

sudo apt install libasio-dev libtinyxml2-dev

3.1.2.2. OpenSSL¶

OpenSSL is a robust toolkit for the TLS and SSL protocols and a general-purpose cryptography library. Install OpenSSL using the package manager of the appropriate Linux distribution. For example, on Ubuntu use the command:

sudo apt install libssl-dev

3.1.3. Colcon installation¶

colcon is a command line tool based on CMake aimed at building sets of software packages. This section explains how to use it to compile eProsima Fast DDS and its dependencies.

Install the ROS 2 development tools (colcon and vcstool) by executing the following command:
```
pip3 install -U colcon-common-extensions vcstool
```
Note

If this fails due to an Environment Error, add the --user flag to the pip3 installation command.

Create a Fast-DDS directory and download the repos file that will be used to install eProsima Fast DDS and its dependencies:

mkdir ~/Fast-DDS
cd ~/Fast-DDS
wget https://raw.githubusercontent.com/eProsima/Fast-DDS/master/fastrtps.repos
mkdir src
vcs import src < fastrtps.repos

Build the packages:
```
colcon build
```

Note

Being based on CMake, it is possible to pass the CMake configuration options to the colcon build command. For more information on the specific syntax, please refer to the CMake specific arguments page of the colcon manual.

3.1.3.1. Run an application¶

When running an instance of an application using eProsima Fast DDS, the colcon overlay built in the dedicated Fast-DDS directory must be sourced. There are two possibilities:

Every time a new shell is opened, prepare the environment locally by typing the command:
```
source ~/Fast-DDS/install/setup.bash
```
Add the sourcing of the colcon overlay permanently to the PATH, by typing the following:
```
echo 'source ~/Fast-DDS/install/setup.bash' >> ~/.bashrc
```

3.1.4. CMake installation¶

This section explains how to compile eProsima Fast DDS with CMake, either locally or globally.

3.1.4.1. Local installation¶

Create a Fast-DDS directory where to download and build eProsima Fast DDS and its dependencies:
```
mkdir ~/Fast-DDS
```

Clone the following dependencies and compile them using CMake.

Foonathan memory

cd ~/Fast-DDS
git clone https://github.com/eProsima/foonathan_memory_vendor.git
mkdir foonathan_memory_vendor/build
cd foonathan_memory_vendor/build
cmake .. -DCMAKE_INSTALL_PREFIX=~/Fast-DDS/install -DBUILD_SHARED_LIBS=ON
sudo cmake --build . --target install

Fast CDR

cd ~/Fast-DDS
git clone https://github.com/eProsima/Fast-CDR.git
mkdir Fast-CDR/build
cd Fast-CDR/build
cmake .. -DCMAKE_INSTALL_PREFIX=~/Fast-DDS/install
sudo cmake --build . --target install

Once all dependencies are installed, install eProsima Fast DDS:

cd ~/Fast-DDS
git clone https://github.com/eProsima/Fast-DDS.git
mkdir Fast-DDS/build
cd Fast-DDS/build
cmake ..  -DCMAKE_INSTALL_PREFIX=~/Fast-DDS/install -DCMAKE_PREFIX_PATH=~/Fast-DDS/install
sudo cmake --build . --target install

Note

By default, eProsima Fast DDS does not compile tests. However, they can be activated by downloading and installing Gtest.

3.1.4.2. Global installation¶

To install eProsima Fast DDS system-wide instead of locally, remove all the flags that appear in the configuration steps of Fast-CDR and Fast-DDS, and change the first in the configuration step of foonathan_memory_vendor to the following:

-DCMAKE_INSTALL_PREFIX=/usr/local/ -DBUILD_SHARED_LIBS=ON

3.1.4.3. Run an application¶

When running an instance of an application using eProsima Fast DDS, it must be linked with the library where the packages have been installed, which in the case of system-wide installation is: /usr/local/lib/ (if local installation is used, adjust for the correct directory). There are two possibilities:

Prepare the environment locally by typing the command:
```
export LD_LIBRARY_PATH=/usr/local/lib/
```

Add it permanently it to the PATH, by typing:

echo 'export LD_LIBRARY_PATH=/usr/local/lib/' >> ~/.bashrc

3.2. Fast DDS-Gen installation¶

This section provides the instructions for installing Fast DDS-Gen in a Linux environment from sources. Fast DDS-Gen is a Java application that generates source code using the data types defined in an IDL file. Please refer to Introduction for more information.

3.2.1. Requirements¶

In order to compile Fast DDS-Gen, the following packages need to be installed in the system:

Java JDK
Gradle

3.2.1.1. Java JDK¶

The JDK is a development environment for building applications and components using the Java language. Download and install it at the following the steps given in the Oracle website.

3.2.1.2. Gradle¶

Gradle is an open-source build automation tool. Download and install the last stable version of Gradle in the preferred way.

3.2.2. Compiling Fast DDS-Gen¶

Once the requirements above are met, compile Fast DDS-Gen by following the steps below:

cd ~
git clone --recursive https://github.com/eProsima/Fast-DDS-Gen.git
cd Fast-DDS-Gen
gradle assemble

Note

If errors occur during compilation or you do not wish to install gradle, an executable script is included which will download a gradle temporarily for the compilation step.

./gradlew assemble

3.2.2.1. Contents¶

The Fast-DDS-Gen folder contains the following packages:

share/fastddsgen, where the generated Java application is.
scripts, containing some user friendly scripts.

Note

To make these scripts accessible from any shell session and directory, add the scripts folder path to the PATH environment variable using the method described above.