Why upgrade? I'm not a lawyer, but here's my take on the differences
to version 2:
* Software patents: better protection against abuse of patents to
prevent users from exercising the rights under the GPL. I doubt
we'll get hit with a patent suit, but it's a good move just on
general principles.
* License compatibility: compatible with more free licenses, i.e. can
"steal" more free software for use in Empire. I don't expect to steal
much, but it's nice to have the option.
* Definition of "source code": modernization of some details for today's
networked world, to make it easier to distribute the software. Not
really relevant to us now, as we normally distribute full source code.
* Tivoization: this is about putting GPL-licensed software in hardware,
then make the hardware refuse to run modified software. "Neat" trick
to effectively deny its users their rights under the GPL. Abuse was
"pioneered" by TiVo (popular digital video recorders). GPLv3 forbids
it. Unlikely to become a problem for us.
* Internationalization: more careful wording, to harden the license
outside the US. The lawyers tell us it better be done that way.
* License violations: friendlier way to deal with license violations.
This has come out of past experience enforcing the GPL.
* Additional permissions: Probably not relevant to us.
Also include myself in the list of principal authors.
Failing a command with code RET_SYN prints help and doesn't charge
BTUs. Failing with code RET_FAIL doesn't print help and charges BTUs.
A couple of command failures were changed or added recently to fail
with RET_SYN, because they're due to invalid player input. Some of
them, however, can happen after the command already did something, so
BTUs must be charged, or else players can deliberately fail the
command to save BTUs:
* Commit 9eda5f87 adds RET_SYN failures when getting player input
fails for:
- arm third argument
- deliver fourth argument
- fire third argument
- lmine second argument
- order d fourth argument
- range second argument
- sail second argument
- tend third argument
* Commit be41e70f likewise for:
- designate second argument
- morale second argument
- set third argument
- tend fourth argument
* Commit d000bf92 likewise (with a bogus commit message) for bdes
second argument.
* Commit 9f4ce71a likewise for ltend third and fourth argument.
* Commit 9031b03b changes failure code from RET_FAIL when getting
player input fails for threshold third argument. It adds RET_SYN
failure when the argument is bad. Some bad arguments already failed
that way before.
* Commit a7cf69af changes it from RET_FAIL when designate second
argument is bad.
Change them all to fail with RET_FAIL.
Many other places have the same bug, but those are left for another
day.
There were two checks meant to enforce positive numbers, both dating
back to the earliest known versions of the code, and both wrong.
The first one applied only to thresholds given with the command, not
ones prompted for, and it incorrectly rejected numbers starting with +
or prefixed by whitespace. Remove it.
The second one failed to reject negative numbers when prefixed by
whitespace. Fix.
Fortunately, the update doesn't conjure up stuff to satisfy negative
thresholds.
other. Ensure headers in include/ can be included in any order
(except for econfig-spec.h, which is special). New header types.h to
help avoid inclusion cycles. Sort include directives. Remove some
superflous includes.
I_BAR, I_FOOD, I_OIL, I_LCM, I_HCM, I_UW, I_RAD, I_MAX): Turn macros
into enumeration constants.
(i_type): New. Use where appropriate. No functional changes, except
that I_NONE is now catched properly in a few places.
(give, deliver_it): Use it instead of 9990.
(load_comm_ship, load_comm_land, rese): Use it instead of 9999.
(thre): Use it instead of 10000.
(check_market, explore, move, pln_dropoff): Use it instead of 32767.
(unload_it): Use it instead of 99999 (which couldn't possibly work,
but what do you expect from the autonav code).
To save space, the ancients invented `variables': a collection of
key-value pairs, missing means zero value, space for `enough' keys.
This complicates the code, as assigning to a `variable' can fail for
lack of space. Over time, `enough' increased, and for quite some time
now `variables' have been *wasting* space. This changeset replaces
them, except in struct mchrstr, struct lchrstr and struct pchrstr,
where they are read-only, and will be replaced later. It is only a
first step; further cleanup is required. To simplify and minimize
this necessarily huge changeset, the new item[] arrays have an unused
slot 0, and the old variable types V_CIVIL, ... are still defined, but
must have the same values as the item types I_CIVIL, ...
thread entrypoints:
(lwpSelect, shutdown_sequence): Parameters didn't match thread entry
point prototype.
(lwpEntryPoint): Arguments didn't match thread entry point prototype.
Change linkage of functions without prototype declaration to static
where possible.
Remove some superflous declarations, replace others by suitable
includes.
