The idea is that we have strvs like list of server names or addresses, where
the majority of strings is rather short, but some are long and there can
potentially be many strings. So formattting them either all on one line or all
in separate lines leads to output that is either hard to read or uses way too
many rows. We want to wrap them, but relying on the pager to do the wrapping is
not nice. Normal text has a lot of redundancy, so when the pager wraps a line
in the middle of a word the read can understand what is going on without any
trouble. But for a high-density zero-redundancy text like an IP address it is
much nicer to wrap between words. This also makes c&p easier.
This adds a variant of TABLE_STRV which is wrapped on output (with line breaks
inserted between different strv entries).
The change table_print() is quite ugly. A second pass is added to re-calculate
column widths. Since column size is now "soft", i.e. it can adjust based on
available columns, we need to two passes:
- first we figure out how much space we want
- in the second pass we figure out what the actual wrapped columns
widths will be.
To avoid unnessary work, the second pass is only done when we actually have
wrappable fields.
A test is added in test-format-table.
We have plenty of code in our codebase that outputs tables to the
console, and all is homegrown and awful. Let's replace it with a generic
implementation that can do automatically what the old implementations
did manually.
Features:
1. Ellipsation (for fields overly long) and alignment (for
fields overly short)
2. Sorting of rows
3. automatically copies formatting from the same cell in the row above
4. Heavy use of varargs to make putting together tables easy
5. can expand and compress tables, with weights
6. Has a minimal understanding of unicode wide characters in order to
match unicode strings to character cell terminals.
7. Columns can be reordered and individually turned off.
8. pretty printing for various data types
And more.
