Re: bin/59956: gpt(8): show human-readable units

[Robert Elz <kre%munnari.OZ.AU@localhost>]

I have this working now in a fashion which looks OK to me
(note that the code always printed (a degree of) humanized
numbers when used as show -a, or show -[ib] arg, it is only
the simple "show" case (to print the entire GPT table) where
it never did.)

Nevertheless I have made some changes to the others as well,
though when I play more I might limit some of that to verbose
mode (gpt -v show ...).

No doc on the changes yet of course, but that will come.

A example, one table, shown 3 ways (the last is the traditional version):

jacaranda$ ./gpt show -Ah ld1    # 'A' for "approximately"
  start     size  index  contents
      0     512B         PMBR
   512B     512B         Pri GPT header
   1.0K      16K         Pri GPT table
    17K     1.0M         Unused
   1.0M     255M      1  GPT part - EFI System
   256M     5.7G      2  GPT part - NetBSD FFSv1/FFSv2
   6.0G     1.0T      4  GPT part - NetBSD RAIDFrame component
   1.0T     992K         Unused
   1.0T     769G      5  GPT part - NetBSD ccd component
   1.8T      64G      3  GPT part - NetBSD swap
   1.8T      16K         Sec GPT table
   1.8T     512B         Sec GPT header
jacaranda$ ./gpt show -h ld1
               start               size  index  contents
                   0               512B         PMBR
                512B               512B         Pri GPT header
                  1K                16K         Pri GPT table
                 17K              1007K         Unused
                  1M               255M      1  GPT part - EFI System
                256M       5G 767M 992K      2  GPT part - NetBSD FFSv1/FFSv2
       5G 1023M 992K             1T 32K      4  GPT part - NetBSD RAIDFrame component
               1T 6G               992K         Unused
          1T 6G 992K      769G 269M 32K      5  GPT part - NetBSD ccd component
        1T 775G 270M  63G 771M 71K 512B      3  GPT part - NetBSD swap
1T 839G 17M 71K 512B                16K         Sec GPT table
1T 839G 17M 87K 512B               512B         Sec GPT header
jacaranda$ ./gpt show ld1
       start          size  index  contents
           0             1         PMBR
           1             1         Pri GPT header
           2            32         Pri GPT table
          34          2014         Unused
        2048        522240      1  GPT part - EFI System
      524288      12058560      2  GPT part - NetBSD FFSv1/FFSv2
    12582848    2147483712      4  GPT part - NetBSD RAIDFrame component
  2160066560          1984         Unused
  2160068544    1613260864      5  GPT part - NetBSD ccd component
  3773329408     133699727      3  GPT part - NetBSD swap
  3907029135            32         Sec GPT table
  3907029167             1         Sec GPT header

And just in case idiocy is desired - decimal GB (etc):

jacaranda$ ./gpt show -AH ld1
  start     size  index  contents
      0     512B         PMBR
   512B     512B         Pri GPT header
   1.0k      16k         Pri GPT table
    17k     1.0M         Unused
   1.0M     267M      1  GPT part - EFI System
   268M     6.2G      2  GPT part - NetBSD FFSv1/FFSv2
   6.4G     1.1T      4  GPT part - NetBSD RAIDFrame component
   1.1T     1.0M         Unused
   1.1T     826G      5  GPT part - NetBSD ccd component
   1.9T      68G      3  GPT part - NetBSD swap
   2.0T      16k         Sec GPT table
   2.0T     512B         Sec GPT header

(Yes, that's a "2TB" M.2 NVME).

Comments welcome (the other options, -l, -u, even -x to a degree (not with -A)
all still work of course).

kre