Building open62541

Building the Examples

Using the GCC compiler, the following calls build the examples on Linux.

cp /path-to/open62541.* . # copy single-file distribution to the local directory
cp /path-to/examples/server_variable.c . # copy the example server
gcc -std=c99 open62541.c server_variable.c -o server

Building the Library

Building with CMake on Ubuntu or Debian

sudo apt-get install git build-essential gcc pkg-config cmake python python-six

# enable additional features
sudo apt-get install cmake-curses-gui # for the ccmake graphical interface
sudo apt-get install libmbedtls-dev # for encryption support
sudo apt-get install check # for unit tests
sudo apt-get install python-sphinx graphviz # for documentation generation
sudo apt-get install python-sphinx-rtd-theme # documentation style

cd open62541
mkdir build
cd build
cmake ..

# select additional features
ccmake ..

# build documentation
make doc # html documentation
make doc_pdf # pdf documentation (requires LaTeX)

Building with CMake on Windows

Here we explain the build process for Visual Studio (2013 or newer). To build with MinGW, just replace the compiler selection in the call to CMake.

cd <path-to>\open62541
mkdir build
cd build
<path-to>\cmake.exe .. -G "Visual Studio 14 2015"
:: You can use use cmake-gui for a graphical user-interface to select features
  • Then open buildopen62541.sln in Visual Studio 2015 and build as usual

Building on OS X

brew install cmake
pip install six # python 2/3 compatibility workarounds
pip install sphinx # for documentation generation
pip install sphinx_rtd_theme # documentation style
brew install graphviz # for graphics in the documentation
brew install check # for unit tests
brew install userspace-rcu # for multi-threading support

Follow Ubuntu instructions without the apt-get commands as these are taken care of by the above packages.

Building on OpenBSD

The procedure below works on OpenBSD 5.8 with gcc version 4.8.4, cmake version 3.2.3 and Python version 2.7.10.

  • Install a recent gcc, python and cmake:
pkg_add gcc python cmake
  • Tell the system to actually use the recent gcc (it gets installed as egcc on OpenBSD):
export CC=egcc CXX=eg++
  • Now procede as described for Ubuntu/Debian:
cd open62541
mkdir build
cd build
cmake ..

Build Options

The open62541 project uses CMake to manage the build options, for code generation and to generate build projects for the different systems and IDEs. The tools ccmake or cmake-gui can be used to graphically set the build options.

Most options can be changed manually in ua_config.h (open62541.h for the single-file release) after the code generation. But usually there is no need to adjust them.

Build Type and Logging

  • RelWithDebInfo -O2 optimization with debug symbols
  • Release -O2 optimization without debug symbols
  • Debug -O0 optimization with debug symbols
  • MinSizeRel -Os optimization without debug symbols

The SDK logs events of the level defined in UA_LOGLEVEL and above only. The logging event levels are as follows:

  • 600: Fatal
  • 500: Error
  • 400: Warning
  • 300: Info
  • 200: Debug
  • 100: Trace

UA_BUILD_* group

By default only the shared object or the library open62541.dll and open62541.dll.a resp. open62541.lib are build. Additional artifacts can be specified by the following options:

Compile example servers and clients from examples/xyz.c. A static and a dynamic binary is linked, respectively.
Compile unit tests with Check framework. The tests can be executed with make test
Generate an OPC UA information model from a nodeset XML (experimental)
Generate a self-signed certificate for the server (openSSL required)

UA_ENABLE_* group

This group contains build options related to the supported OPC UA features.

Enable subscriptions
Enable the Method service set
Enable dynamic addition and removal of nodes at runtime
Compile a single-file release into the files open62541.c and open62541.h
Enable multi-threading support
Measure the coverage of unit tests
Enable Discovery Service (LDS)
Enable Discovery Service with multicast support (LDS-ME)
Enable Discovery Semaphore support

Some options are marked as advanced. The advanced options need to be toggled to be visible in the cmake GUIs.

Add the type and member names to the UA_DataType structure. Enabled by default.
Compile the human-readable name of the StatusCodes into the binary. Enabled by default.
Use the full NS0 instead of a minimal Namespace 0 nodeset UA_FILE_NS0 is used to specify the file for NS0 generation from namespace0 folder. Default value is Opc.Ua.NodeSet2.xml
Enable udp extension

UA_DEBUG_* group

This group contains build options mainly useful for development of the library itself.

Enable assertions and additional definitions not intended for production builds
Dump every package received by the server as hexdump format

Building a shared library

open62541 is small enough that most users will want to statically link the library into their programs. If a shared library (.dll, .so) is required, this can be enabled in CMake with the BUILD_SHARED_LIBS option. Note that this option modifies the ua_config.h file that is also included in open62541.h for the single-file distribution.

Minimizing the binary size

The size of the generated binary can be reduced considerably by adjusting the build configuration. First, in CMake, the build type can be set to CMAKE_BUILD_TYPE=MinSizeRel. This sets the compiler flags to minimize the binary size. The build type also strips out debug information. Second, the binary size can be reduced by removing features via the build-flags described above.

Especially, logging takes up a lot of space in the binary and might not be needed in embedded scenarios. Setting UA_LOGLEVEL to a value above 600 (=FATAL) disables all logging. In addition, the feature-flags UA_ENABLE_TYPENAMES and UA_ENABLE_STATUSCODE_DESCRIPTIONS add static information to the binary that is only used for human-readable logging and debugging.

The RAM requirements of a server are mostly due to the following settings:

  • The size of the information model
  • The number of connected clients
  • The configured maximum message size that is preallocated

Installation and packaging

You can install open62541 using the well known make install command. This allows you to use pre-built libraries and headers for your own project.

To override the default installation directory use cmake -DCMAKE_INSTALL_PREFIX=/some/path. Based on the SDK Features you selected, as described above, these features will also be included in the installation. Thus we recommend to enable as many features as possible for the installed binary.

In your own CMake project you can then include the open62541 library using:

# optionally you can also specify a specific version
# e.g. find_package(open62541 0.3.0)
find_package(open62541 REQUIRED COMPONENTS FullNamespace DiscoveryMulticast)
add_executable(main main.cpp )
target_link_libraries(main open62541)

A full list of enabled features during build time is stored in the CMake Variable open62541_COMPONENTS_ALL