We already have code to fetch and find binaries specified in a cross
file, so use the same code for exe_wrapper. This allows us to handle
the same corner-cases that were fixed for other cross binaries.
* add support for cups dependencies
libcups has its own cups-config tool rather than using pkg-config.
This adds support for cups-config, based on pcap-config and
sdl2-config implementations.
This change also includes the unit test case and documentation for
cups dependency object implementation, and libcups2 dep to CI image.
Libpcap has its own pcap-config tool rather than using pkg-config. Add
support for pcap-config, based on the existing implementation of
sdl2-config that is there already.
We prefer pkg-config files, though only OpenMPI supplies them.
Otherwise, check environment variables and search for wrappers and ask
them for what to do.
This class now consolidates a lot of the logic that each external
dependency was duplicating in its class definition.
All external dependencies now set:
* self.version
* self.compile_args and self.link_args
* self.is_found (if found)
* self.sources
* etc
And the abstract ExternalDependency class defines the methods that
will fetch those properties. Some classes still override that for
various reasons, but those should also be migrated to properties as
far as possible.
Next step is to consolidate and standardize the way in which we call
'configuration binaries' such as sdl2-config, llvm-config, pkg-config,
etc. Currently each class has to duplicate code involved with that
even though the format is very similar.
Currently only pkg-config supports multiple version requirements, and
some classes don't even properly check the version requirement. That
will also become easier now.