main/lttng-ust: fix busybox mkdir detection
This aport fails to build when cmake is installed on the host.
What happens is that the presence of cmake is detected and doc/examples
tries to recurse into a cmake-related subdir. It needs to create a build directory. But earlier - configure failed to recognize busybox mkdir as "a race-free mkdir -p", so configure used config/install-sh
instead, and since it uses a relative(!) path to it, that relative path is no longer valid after cd
:
cd $$subdir && $(MKDIR_P) build && ...
The right fix is to fix the doc/examples/Makefile.am
, but the easier one it to fix the mkdir detection.
configure runs mkdir --version
and detects busybox with a 'BusyBox '*)
pattern, but busybox first print the error message, so the subject text does not start with "BusyBox". The suggested patch just matches "BusyBox" anywhere inside the message.