Development versions of cmocka require the intmax_t and uintmax_t types
to be defined by the time the test code includes the <cmocka.h> header.
These types are defined in the <stdint.h> header, which is included by
the <inttypes.h> header, which in turn is already explicitly included by
some of the programs in the tests/ directory. Ensure all programs in
that directory that include the <cmocka.h> header also include the
<inttypes.h> header to future-proof the code while keeping the change
set minimal and the resulting code consistent. Also prevent explicitly
including the <stdint.h> header in those programs as it is included by
the <inttypes.h> header.
The `isc_histosummary_t` functions were written in the early days of
`hg64` and carried over when I brought `hg64` into BIND. They were
intended to be useful for graphing cumulative frequency distributions
and the like, but in practice whatever draws charts is better off with
a raw histogram export. Especially because of the poor performance of
the old functions.
The replacement `isc_histo_quantiles()` function is intended for
providing a few quantile values in BIND's stats channel, when the user
does not want the full histogram. Unlike the old functions, the caller
provides all the query fractions up-front, so that the values can be
found in a single scan instead of a scan per value. The scan is from
larger values to smaller, since larger quantiles are usually more
interesting, so the scan can bail out early.
This is an adaptation of my `hg64` experiments for use in BIND.
As well as renaming everything according to ISC style, I have
written some more extensive tests that ensure the edge cases are
correct and the fenceposts are in the right places.
I have added utility functions for working with precision in terms of
decimal significant figures as well as this code's native binary.
