Parse > 2GiB file sizes correctly

We were using atol(), which on 32 bit, cannot handle values greater than
2GiB, which is fail.

Switch to a strtoull() wrapper function tailored toward parsing off_t
values. This allows parsing of very large positive integer values. off_t
is a signed type, but in our usages, we never parse or have a need for
negative values, so the function will return -1 on error.

Before:
    $ pacman -Si flightgear-data | grep Size
    Download Size  : 2097152.00 K
    Installed Size : 2097152.00 K

After:
    $ ./src/pacman/pacman -Si flightgear-data | grep Size
    Download Size  : 2312592.52 KiB
    Installed Size : 5402896.00 KiB

Signed-off-by: Dan McGee <dan@archlinux.org>

0 files changed, 0 insertions, 0 deletions