[PATCH] Rebasing on Padraig's gnulib fallocate module and cleaning up

[Matěj Cepl]

Hi,

the craziness around F11 finished so I am using a little bit of
time I have to make one more round of my truncate/fallocate
patch (together with mkfile script). I wanted to make my patch
working with the Pádraig's fallocate gnulib module and clean up
tests (they should all pass now).

I am fully aware that fallocate will probably be changed a little
bit, so I will have to fix my patch once more, but I wanted to
make this round to fix integration with gnulib.

The problem I have is that a) I am really not sure I understand
how gnulib modules work (or better to say, I have no clue), b) I
am developing this on F11 with ext4 so I am probably really not
testing integration with gnulib at all.

My main question is that I don't understand how the program
should actually use gnulib module. Should I explicitly test in
the program for ENOSYS and react automatically (either just print
warning and behave as if -a parameter was not used, or write a
lot of \0 characters to fill the space) or is this somehow
magically done by gnulib module?

Could somebody take a look at my patch and help me with the
integration of fallocate gnulib module, please?

Thank you,

Matěj