User macro reference
====================

.. cmake:macro:: add_message_files(DIRECTORY dir FILES file1 [file2...] [BASE_DIR base_dir] [NOINSTALL])

   :param DIRECTORY: Directory containing messages.  May be absolute or
     relative to ``CMAKE_CURRENT_SOURCE_DIR``.  The name will also be used as the install folder as
     `share/<pkgname>/<DIRECTORY>`. Default is `msg`.
   :param FILES:  Files containing messages, relative to `msgdir`
   :param BASE_DIR:  Absolute path used and only used as an alternate source message folder.  Has
     precedence over DIRECTORY.  Only used by `add_action_files()`.
   :param NOINSTALL: Do not automatically install the messages to the package's share/ directory.

   Register the listed files as requiring message generation and installation.


.. cmake:macro:: add_service_files(DIRECTORY dir FILES file1 [file2...] [PACKAGE pkgname] [NOINSTALL])

   Same as add_message_files... but for services.


.. cmake:macro:: generate_messages(DEPENDENCIES deps [LANGS lang1 lang2...])

   :param DEPENDENCIES: Names of packages containing messages
      contained by messages in the current package.  Got it?  i.e. if
      one of our messages contains std_msgs.Header, ``std_msgs``
      should appear in this list.
   :param LANGS:  Restrict generation to the listed languages.

   Triggers the generation of message generation targets.  i.e. in
   project ``foo`` with generators ``gencpp`` and ``genpy`` accessible
   in the workspace, triggers creation of targets ``foo_gencpp`` and
   ``foo_genpy``.


Now, if your code does depend on generated messages you need to add a dependency.
E.g. if you target foo depends on the C++ messages of your current bar project, you need to add:

``add_dependencies(foo bar_gencpp)``

(the ``bar_cpp`` target is automatically created when you generate messages)