They're really redundant, and removing the next pointer makes for a
slightly smaller cvar struct. Cvar_Select was added to allow finding
lists of matching cvars.
The tab-completion and config saving code was reworked to use the hash
table DO functions. Comments removed since the code was completely
rewritten, but still many thanks to EvilTypeGuy and Fett.
This is an extremely extensive patch as it hits every cvar, and every
usage of the cvars. Cvars no longer store the value they control,
instead, they use a cexpr value object to reference the value and
specify the value's type (currently, a null type is used for strings).
Non-string cvars are passed through cexpr, allowing expressions in the
cvars' settings. Also, cvars have returned to an enhanced version of the
original (id quake) registration scheme.
As a minor benefit, relevant code having direct access to the
cvar-controlled variables is probably a slight optimization as it
removed a pointer dereference, and the variables can be located for data
locality.
The static cvar descriptors are made private as an additional safety
layer, though there's nothing stopping external modification via
Cvar_FindVar (which is needed for adding listeners).
While not used yet (partly due to working out the design), cvars can
have a validation function.
Registering a cvar allows a primary listener (and its data) to be
specified: it will always be called first when the cvar is modified. The
combination of proper listeners and direct access to the controlled
variable greatly simplifies the more complex cvar interactions as much
less null checking is required, and there's no need for one cvar's
callback to call another's.
nq-x11 is known to work at least well enough for the demos. More testing
will come.
Listeners are separate to the main callback as listeners have only
read-only access to the objects, but the main callback is free to modify
the cvar and thus can act as a parser and validator. The listeners are
invoked after the main callback if the cvar is modified. There does not
need to be a main callback for the listeners to be invoked.
quakeio.h -> vfile.h
More diff reduction between trunk and my VFS code. Also took the time to
put some headers in order and fix a few #include's pointed out by moving
things around a bit.