Getting started with ndn-cxx

Supported platforms

ndn-cxx is built against a continuous integration system and has been tested on the following platforms:

• Ubuntu 18.04 / 20.04 / 22.04

• Debian 11

• CentOS Stream 9

• macOS 10.15 / 11 / 12 / 13

ndn-cxx is known to work on the following platforms, although they are not officially supported:

• Alpine >= 3.12

• Fedora >= 29

• Gentoo Linux

• Raspberry Pi OS (formerly Raspbian) >= 2019-06-20

• FreeBSD >= 12.2

Prerequisites

Required

• GCC >= 7.4 or clang >= 6.0 (if you are on Linux or FreeBSD)

• Xcode >= 11.3 or corresponding version of Command Line Tools (if you are on macOS)

• Python >= 3.6

• pkg-config

• Boost >= 1.65.1

• OpenSSL >= 1.1.1

• SQLite 3.x

To build ndn-cxx from source, one must first install a C++ compiler and all necessary development tools and libraries:

• On Debian and Ubuntu

  In a terminal, enter:

  sudo apt install build-essential pkg-config python3-minimal libboost-all-dev libssl-dev libsqlite3-dev
  

• On CentOS and Fedora

  In a terminal, enter:

  sudo dnf install gcc-c++ pkgconf-pkg-config python3 boost-devel openssl-devel sqlite-devel
  

• On macOS

  • Install either Xcode (from the App Store) or the Command Line Tools (with xcode-select --install)

  • If using Homebrew (recommended), enter the following in a terminal:

    brew install boost openssl pkg-config
    brew install python  # only on macOS 10.14 and earlier
    

    Warning

    If a major OS upgrade is performed after installing the dependencies with Homebrew, remember to reinstall all packages.

• On FreeBSD

  In a terminal, enter:

  sudo pkg install pkgconf python3 boost-libs openssl sqlite3
  

Optional

To build tutorials, man pages, and API documentation the following additional dependencies need to be installed:

• doxygen

• graphviz

• sphinx >= 4.0

• sphinxcontrib-doxylink

The following lists the steps to install these prerequisites on various common platforms.

Note

On Linux, you may need to add $HOME/.local/bin to the PATH environment variable for your user, for example:

export PATH="${HOME}/.local/bin${PATH:+:}${PATH}"

• On Debian and Ubuntu:

  sudo apt install doxygen graphviz python3-pip
  pip3 install --user sphinx sphinxcontrib-doxylink
  

• On CentOS and Fedora:

  sudo dnf install doxygen graphviz python3-pip
  pip3 install --user sphinx sphinxcontrib-doxylink
  

• On macOS:

  brew install doxygen graphviz
  sudo pip3 install sphinx sphinxcontrib-doxylink
  

• On FreeBSD:

  sudo pkg install doxygen graphviz py39-sphinx
  

Build

Note

These are instructions for regular builds of ndn-cxx (release mode). If you are planning to develop the ndn-cxx code itself, you should do a Development build.

To build in a terminal, change directory to the ndn-cxx root, then enter:

./waf configure
./waf
sudo ./waf install

By default, only the shared variant of the ndn-cxx library will be built. To build the static library, pass --enable-static to the ./waf configure command:

./waf configure --enable-static

To disable the build of the shared library and build only the static library, use the additional --disable-shared option. Note that at least one variant of the library needs to be enabled.

./waf configure --enable-static --disable-shared

On Linux, it is necessary to run the following command after the shared library has been installed:

sudo ldconfig

Note

When the library is installed in a non-default location (in general: not in /usr/lib or /usr/local/lib; on some Linux distros like Fedora and its derivatives, including CentOS: not in /usr/lib), the following additional actions may be necessary.

The library installation path should be added to /etc/ld.so.conf or in /etc/ld.so.conf.d/*.conf before running ldconfig. For example:

echo /usr/local/lib | sudo tee /etc/ld.so.conf.d/ndn-cxx.conf

Alternatively, the LD_LIBRARY_PATH environment variable can be set to point to the installation directory of the shared library:

export LD_LIBRARY_PATH=/usr/local/lib

The ./waf install command installs the following files:

• <LIBPATH>/libndn-cxx.a: static NDN C++ library (if enabled).

• <LIBPATH>/libndn-cxx.so, <LIBPATH>/libndn-cxx.so.<VERSION> (on Linux), <LIBPATH>/libndn-cxx.dylib, <LIBPATH>/libndn-cxx.<VERSION>.dylib (on macOS): shared NDN C++ library (if enabled).

• <LIBPATH>/pkgconfig/libndn-cxx.pc: pkgconfig file storing all necessary flags to build against the library. For example, if the pkg-config or pkgconf-pkg-config package is installed and PKG_CONFIG_PATH is configured properly (or if <LIBPATH>/pkgconfig is a default search path), the command pkg-config --cflags --libs libndn-cxx will return all necessary compile and link flags for the library.

• <BINPATH>/ndnsec: command-line tool to manage NDN keys and certificates.

• <BINPATH>/ndnsec-*: convenience aliases for ndnsec tools.

If configured with tests (./waf configure --with-tests), the above commands will also produce:

• build/unit-tests: a unit test binary for the library.

1.5 GB available memory per CPU core is necessary for efficient compilation. On a multi-core machine with less than 1.5 GB available memory per CPU core, limit the objects being compiled in parallel with ./waf -jN, where N is the amount of available memory divided by 1.5 GB (e.g., ./waf -j2 for 3 GB of memory). This should avoid memory thrashing and result in faster compilation.

Build with examples

By default, the examples in the examples/ directory will not be built. To enable them, pass --with-examples during the configuration step:

./waf configure --with-examples
./waf
sudo ./waf install
sudo ldconfig  # on Linux only

To run the examples:

# trivial producer app
./build/examples/producer

# trivial consumer app
./build/examples/consumer

# trivial consumer app with timers
./build/examples/consumer-with-timer

If you want to make a new sample application, just create a .cpp file inside the examples/ directory and it will be compiled during the next run of ./waf:

cp examples/consumer.cpp examples/my-new-app.cpp
... # edit examples/my-new-app.cpp with your preferred editor
./waf
sudo ./waf install
sudo ldconfig  # on Linux only
./build/examples/my-new-app

Debug symbols

The default compiler flags include debug symbols in binaries. This should provide more meaningful debugging information if ndn-cxx or your application crashes.

If this is not desired, the default flags can be overridden to disable debug symbols. The following example shows how to completely disable debug symbols and configure ndn-cxx to be installed into /usr with configuration in the /etc directory.

CXXFLAGS="-O2" ./waf configure --prefix=/usr --sysconfdir=/etc
./waf
sudo ./waf install

Customizing the compiler

To build ndn-cxx with a different compiler (rather than the platform default), set the CXX environment variable to point to the compiler binary. For example, to build with clang on Linux, use the following:

CXX=clang++ ./waf configure

Building the documentation

Tutorials and API documentation can be built using the following commands:

# Full set of documentation (tutorials + API) in build/docs
./waf docs

# Only tutorials in build/docs
./waf sphinx

# Only API docs in build/docs/doxygen
./waf doxygen

If sphinx-build is detected during ./waf configure, man pages will automatically be built and installed during the normal build process (i.e., during ./waf and ./waf install). By default, man pages will be installed into ${PREFIX}/share/man (the default value for PREFIX is /usr/local). This location can be changed during the ./waf configure stage using the --prefix, --datarootdir, or --mandir options.

For further details, please refer to ./waf --help.

Development build

The following is the suggested build procedure for development builds:

./waf configure --debug --with-tests
./waf
sudo ./waf install
sudo ldconfig  # on Linux only

In a development build, most compiler optimizations will be disabled and all warnings will be treated as errors. This default behavior can be overridden by setting the CXXFLAGS environment variable before running ./waf configure, for example:

CXXFLAGS="-O1 -g3 -Wall" ./waf configure --debug --with-tests
./waf