Let's define a set of macros for making output of permyriad values easy.
They are printed in pure ASCII, i.e. without the permille/permyriad
suffix, using just percent and two places after the dot.
At various places we accept values scaled to the range 0…2^32-1 which
are exposed to the user as percentages/permille/permyriad. Let's add
some helper macros (actually: typesafe macro-like functions) that help
with converting our internal encoding to the external encodings.
benefits: some of the previous code rounded up, some down. let's always
round to nearest, to ensure that our conversions are reversible. Also,
check for overflows correctly.
This also adds a test that makes sure that for the full
percent/permille/permyriad ranges we can convert forth and back without
loss of accuracy.
A good chunk of parse-util.[ch] has been about parsing parts per
hundred/thousand/ten-thousand. Let's split that out into its own file.
No code changes, just some shuffling around.
Lennart Poettering