Building open62541

Building the Library

open62541 uses CMake to build the library and binaries. CMake generates a Makefile or a Visual Studio project. This is then used to perform the actual build.

Building with CMake on Ubuntu or Debian

sudo apt-get install git build-essential gcc pkg-config cmake python3

# 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 libsubunit-dev # for unit tests
sudo apt-get install python3-sphinx graphviz  # for documentation generation
sudo apt-get install python3-sphinx-rtd-theme # documentation style

cd open62541
mkdir build
cd build
cmake ..
make

# select additional features
ccmake ..
make

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

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. In order to use open62541 as a shared library (.dll or .so) make sure to activate the BUILD_SHARED_LIBS CMake option.

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

In your own CMake project you can then include the open62541 library. A simple CMake project definition looks as follows:

cmake_minimum_required(VERSION 3.5)
project("open62541SampleApplication")
add_executable(main main.c)

# Linux/Unix configuration using pkg-config
find_package(PkgConfig)
pkg_check_modules(open62541 REQUIRED open62541)
target_link_libraries(main open62541)

# Alternative CMake-based library definition.
# This might not be included in some package distributions.
#
#   find_package(open62541 REQUIRED)
#   target_link_libraries(main open62541::open62541)

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 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

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 ..
make

Building Debian Packages inside Docker Container with CMake on Ubuntu or Debian

This is how to build the Debian packages.

# Assume a fresh checkout of open62541 in the ~/open62541 directory
cd ~/open62541

# Create the debian packaging definitions
python3 ./tools/prepare_packaging.py

# Build the package (generated packages and source will be in the ~ folder)
debuild

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.

Main Build Options

CMAKE_BUILD_TYPE

  • RelWithDebInfo -O2 optimization with debug symbols

  • Release -O2 optimization without debug symbols

  • Debug -O0 optimization with debug symbols

  • MinSizeRel -Os optimization without debug symbols

BUILD_SHARED_LIBS

Build a shared library (dll/so) or (an archive of) object files for linking into a static binary. Shared libraries are recommended for a system-wide install. Note that this option modifies the ua_config.h file that is also included in open62541.h for the single-file distribution.

UA_LOGLEVEL

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

This compilation flag defines which log levels get compiled into the code. In addition, the implementations of Logging Plugin API allow to set a filter for the logging level at runtime. So the logging level can be changed in the configuration without recompiling.

UA_MULTITHREADING

Level of multi-threading support. The supported levels are currently as follows:

  • 0-99: Multithreading support disabled.

  • >=100: API functions marked with the UA_THREADSAFE-macro are protected internally with mutexes. Multiple threads are allowed to call these functions of the SDK at the same time without causing race conditions. Furthermore, this level support the handling of asynchronous method calls from external worker threads.

Select build artefacts

By default only the main library shared object libopen62541.so (open62541.dll) or static linking archive open62541.a (open62541.lib) is built. Additional artifacts can be specified by the following options:

UA_BUILD_EXAMPLES

Compile example servers and clients from examples/*.c.

UA_BUILD_UNIT_TESTS

Compile unit tests. The tests can be executed with make test. An individual test can be executed with make test ARGS="-R <test_name> -V". The list of available tests can be displayed with make test ARGS="-N".

Detailed SDK Features

UA_ENABLE_SUBSCRIPTIONS

Enable subscriptions

UA_ENABLE_SUBSCRIPTIONS_EVENTS

Enable the use of events for subscriptions. This is a new feature and currently marked as EXPERIMENTAL.

UA_ENABLE_SUBSCRIPTIONS_ALARMS_CONDITIONS (EXPERIMENTAL)

Enable the use of A&C for subscriptions. This is a new feature build upon events and currently marked as EXPERIMENTAL.

UA_ENABLE_METHODCALLS

Enable the Method service set

UA_ENABLE_PARSING

Enable parsing human readable formats of builtin data types (Guid, NodeId, etc.). Utility functions that are not essential to the SDK.

UA_ENABLE_NODEMANAGEMENT

Enable dynamic addition and removal of nodes at runtime

UA_ENABLE_AMALGAMATION

Compile a single-file release into the files open62541.c and open62541.h. Not recommended for installation.

UA_ENABLE_IMMUTABLE_NODES

Nodes in the information model are not edited but copied and replaced. The replacement is done with atomic operations so that the information model is always consistent and can be accessed from an interrupt or parallel thread (depends on the node storage plugin implementation).

UA_ENABLE_COVERAGE

Measure the coverage of unit tests

UA_ENABLE_DISCOVERY

Enable Discovery Service (LDS)

UA_ENABLE_DISCOVERY_MULTICAST

Enable Discovery Service with multicast support (LDS-ME)

UA_ENABLE_DISCOVERY_SEMAPHORE

Enable Discovery Semaphore support

UA_ENABLE_ENCRYPTION

Enable encryption support and specify the used encryption backend. The possible options are: - OFF No encryption support. (default) - MBEDTLS Encryption support using mbed TLS - OPENSSL Encryption support using OpenSSL - LIBRESSL EXPERIMENTAL: Encryption support using LibreSSL

UA_ENABLE_ENCRYPTION_TPM2
Enable TPM hardware for encryption. The possible options are:

  • OFF No TPM encryption support. (default)

  • ON TPM encryption support

UA_NAMESPACE_ZERO

Namespace zero contains the standard-defined nodes. The full namespace zero may not be required for all applications. The selectable options are as follows:

  • MINIMAL: A barebones namespace zero that is compatible with most clients. But this namespace 0 is so small that it does not pass the CTT (Conformance Testing Tools of the OPC Foundation).

  • REDUCED: Small namespace zero that passes the CTT.

  • FULL: Full namespace zero generated from the official XML definitions.

The advanced build option UA_FILE_NS0 can be used to override the XML file used for namespace zero generation.

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

UA_ENABLE_TYPEDESCRIPTION

Add the type and member names to the UA_DataType structure. Enabled by default.

UA_ENABLE_STATUSCODE_DESCRIPTIONS

Compile the human-readable name of the StatusCodes into the binary. Enabled by default.

UA_ENABLE_FULL_NS0

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

PubSub Build Options

UA_ENABLE_PUBSUB

Enable the experimental OPC UA PubSub support. The option will include the PubSub UDP multicast plugin. Disabled by default.

UA_ENABLE_PUBSUB_FILE_CONFIG

Enable loading OPC UA PubSub configuration from File/ByteString. Enabling PubSub informationmodel methods also will add a method to the Publish/Subscribe object which allows configuring PubSub at runtime.

UA_ENABLE_PUBSUB_INFORMATIONMODEL

Enable the information model representation of the PubSub configuration. For more details take a look at the following section PubSub Information Model Representation. Disabled by default.

UA_ENABLE_PUBSUB_MONITORING

Enable the experimental PubSub monitoring. This feature provides a basic framework to implement monitoring/timeout checks for PubSub components. Initially the MessageReceiveTimeout check of a DataSetReader is provided. It uses the internal server callback implementation. The monitoring backend can be changed by the application to satisfy realtime requirements. Disabled by default.

Debug Build Options

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

UA_DEBUG

Enable assertions and additional definitions not intended for production builds

UA_DEBUG_DUMP_PKGS

Dump every package received by the server as hexdump format

Minimizing the binary size

The size of the generated binary can be reduced considerably by adjusting the build configuration. With open62541, it is possible to configure minimal servers that require less than 100kB of RAM and ROM.

The following options influence the ROM requirements:

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.

Second, setting UA_NAMESPACE_ZERO to MINIMAL reduces the size of the builtin information model. Setting this option can reduce the binary size by half in some cases.

Third, some features might not be needed and can be disabled to reduce the binary footprint. Examples for this are Subscriptions or encrypted communication.

Last, logging messages take 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_TYPEDESCRIPTION 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

Prebuilt packages

Debian

Debian packages can be found in our official PPA:

Install them with:

sudo add-apt-repository ppa:open62541-team/ppa
sudo apt-get update
sudo apt-get install libopen62541-1-dev

Arch

Arch packages are available in the AUR:

OpenBSD

Starting with OpenBSD 6.7 the ports directory misc/open62541 can build the released version of open62541. Install the binary package from the OpenBSD mirrors:

pkg_add open62541

Building the Examples

Make sure that you have installed the shared library as explained in the previous steps. Then the build system should automatically find the includes and the shared library.

cp /path-to/examples/tutorial_server_firststeps.c . # copy the example server
gcc -std=c99 -o server tutorial_server_firststeps.c -lopen62541