find libavahi with cmake

Question

I need to add libavahi-client3 to cmake dependency of my project. Also need to check libavahi-client3 and libavahi-common3 existence. Problems only with current library(avahi)

Trying to do these things:

find_package(libavahi-common3)
if(NOT libavahi-common3_FOUND)
message(ERROR " libavahi-common3 is not found")
endif(NOT libavahi-common3_FOUND)

OR this variant:

find_library(AVAHI_COMMON_LIBRARY NAMES libavahi-common3)
if(NOT AVAHI_COMMON_LIBRARY_FOUND)
message(ERROR " libavahi-common3 is not found")
endif(NOT AVAHI_COMMON_LIBRARY_FOUND)

Both do not work, i searched for something like findAvahi.cmake, but found nothing. So should i write my own search module or there is another better option?

Answer 1

There is currently no find script for avahi shipping with CMake, which is why your first example does not work. It is important to understand that find_package simply runs an external find script, it does not perform any searching by itself.

Your second example is broken, mixing idioms from find_library and find_package. Please read up on the documentation of find_library and find_path which will help you find the required libraries and include paths.

If you want you can turn that into a find script later (look at the scripts in CMake's module directory to get an idea what such a script should look like), which will allow you to use the more compact find_package for locating the library again. Note that writing a find script that works reasonably well on different platforms is a complex task that will require some research effort to get it right.