Split the core reply formatting code out of control_fmt.c into
control_proto.c. The remaining code in control_format.c deals with
specific subsystems and will eventually move to join those subsystems.
This command does not fit perfectly with the others, since its
second argument is optional and may contain equal signs. Still,
it's probably better to squeeze it into the new metaformat, since
doing so allows us to remove several pieces of the old
command-parsing machinery.
(This should be all of the command that work nicely with positional
arguments only.)
Some of these commands should probably treat extra arguments as
incorrect, but for now I'm trying to be careful not to break
any existing users.
The first line break in particular was mishandled: it was discarded
if no arguments came before it, which made it impossible to
distinguish arguments from the first line of the body.
To solve this, we need to allocate a copy of the command rather than
using NUL to separate it, since we might have "COMMAND\n" as our input.
Fixes ticket 29984.
There _is_ an underlying logic to these commands, but it isn't
wholly uniform, given years of tweaks and changes. Fortunately I
think there is a superset that will work.
This commit adds a parser for some of the most basic cases -- the
ones currently handled by getargs_helper() and some of the
object-taking ones. Soon will come initial tests; then I'll start using
the parser.
After that, I'll expand the parser to handle the other cases that come
up in the controller protocol.
Use a table-based lookup to find the right command handler. This
will serve as the basement for several future improvements, as we
improve the API for parsing commands.
