This should make tag editing less tedious/error-prone. We already used
self-parsing to generate -l/--list in dbgtag.py, but this extends the
idea to tagrepr (now Tag.repr), which is used in quite a few more
scripts.
To make this work the little tag encoding spec had to become a bit more
rigorous, fortunately the only real change was the addition of '+'
characters to mark reserved-but-expected-zero bits.
Example:
TAG_CKSUM = 0x3000 ## v-11 ---- ++++ +pqq
^--^----^----^--^-^-- valid bit, unmatched
'----|----|--|-|-- matches 1
'----|--|-|-- matches 0
'--|-|-- reserved 0, unmatched
'-|-- perturb bit, unmatched
'-- phase bits, unmatched
dbgtag.py 0x3000 => cksumq0
dbgtag.py 0x3007 => cksumq3p
dbgtag.py 0x3017 => cksumq3p 0x10
dbgtag.py 0x3417 => 0x3417
Though Tag.repr still does a bit of manual formatting for the
differences between shrub/normal/null/alt tags.
Still, this should reduce the number of things that need to be changed
from 2 -> 1 when adding/editing most new tags.
Christopher Haster
ffc40da878