if you see error

.infig.status: error: cannot find input file

during ./configure

it is properly due to MSDOS return character issue.

If you system have dos2unix then just simple convert configure.ac/configure.in.
If you don't have unix2dos ... you can try to use vi and run

set ff=unix
wq

then run

autoreconf -vif

after that you can run configure again.

BTW it is suggest to also convert the shell scripts, sometimes they will also cause problems.