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.
Output went to the owner of the nuke instead of the player.
Fortunately, they're the same in normal usage. They can differ only
when a deity drops a foreign nuke from a foreign plane.
The fix also cleans up a misuse of mpr() in kaboom(): it used multiple
calls to print a single line, which creates a separate bulletin for
each part. The read command normally merges the bulletins, but if the
bulletins are more than five seconds apart (clock jumped somehow), we
get a bulletin header in the middle of a line. Fortunately, that
could happen only when a deity drops a foreign nuke. Before commit
a269cdd7 (v4.3.23), it could also happen for missions.
Broken in Empire 2.
When the nuke bounced off a sanctuary, the bulletin to the sanctuary
owner used the attacker's coordinate system. This disclosed the
attacker's origin.
This can happen when hitting a sanctuary, or for ridiculously impotent
nukes: groundburst for dam < 5, airburst for dam < 7. detonate()
returned unpredictable value then.
This screwed up interdiction damage, except for missiles interdicting
ships or land units. Since nothing can move into a sanctuary, the bug
bit only with ridiculously impotent nukes.
Losses of sectors, ships, planes, land units and nukes are tracked in
the lost file. To keep it current, makelost() and makenotlost() were
called whenever one of these changed owners. Cumbersome and
error-prone. In fact, the lost file was never perfectly accurate.
Detect the ownership change in the prewrite callback and call
makelost() / makenotlost() from there. Remove lost file updates from
where they're no longer needed: right before a put. takeover() is a
bit more involved: it doesn't put the sectors, but all callers do,
except for guerrilla(). So remove the lost file update from
takeover(), but add it to guerrilla().
This takes care of lost file update for all ownership changes that go
through ef_write(). It can't take care of any missing updates for
changes that don't go through it.
Planes normally sit in their base (sector or carrier), where they can
be spied, damaged, captured, loaded, unloaded, upgraded and so forth.
All this must not be possible while they fly. There are two kinds of
flying planes: satellites in orbit, and planes flying a sortie.
Satellites in orbit have always been marked with flag PLN_LAUNCHED.
Works. What didn't work was tracking planes flying a sortie.
If you look at one sortie in isolation, up to three groups of planes
can be flying at any point of time: the primary group, which carries
out the sortie's mission (bomb, transport, ...), their escorts, and a
group of hostile planes flying interception or air defense.
The old code attempted to track these planes by passing those groups
to the places that need to know whether a plane is flying. This was
complex and incomplete, and broke down completely for the pin-bombing
command.
It was complex, because the plane code needs to keep track of all the
call chains that can lead to a place that needs to know whether a
plane flies, and pass the groups down the call chains. This leads to
a rather ugly passing of plane groups all over the place.
It was incomplete, because it generally failed to pass the escorts.
And the whole scheme broke down for the pin-bombing command. That's
because pin-bombing asks the player for targets while his planes are
loitering above the target sector. This yields the processor and lets
other code run. Which does not get the flying planes passed.
The new code marks planes and SAMs (but not other missiles) flying a
sortie with flag PLN_LAUNCHED (the previous commit laid the groundwork
for that), and does away with passing around groups of flying planes.
This fixes the following bugs:
* Many commands could interact with foreign planes flying for a
pin-bombing command as if they were sitting in their base. This
includes spying, damaging, capturing, loading, or upgrading them,
and even getting intercepted by them. Any changes to those planes
were wiped out when they landed. Abusable.
* The bomb command could bomb its own escorts, directly (pin-bomb
planes) or through collateral damage, strategic sector damage,
collapsing bridges or nuke damage. The damage to the escorts was
wiped out when they landed.
* If you asked for a plane to fly both in the primary group and the
escort group, you got charged fuel for two sorties instead of one.
* pln_put1() and pln_put() now recognize planes that didn't take off,
and refrain from making them land. Intercept (since commit
c64e2149) and air defense can do that. Making them land had no
ill-effects, but it was still wrong.
There's one new problem: if PLN_LAUNCHED doesn't get reset properly,
due to game crash during flight or some other bug, the plane gets
stuck in the air. Catch and fix that on game start in ef_verify().
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.
(launch_sat, scra, scut, scuttle_ship, scuttle_land, knockdown)
(ac_planedamage, detonate, attack_val, defense_val, air_damage)
(msl_intercept, msl_launch_mindam, pln_prewrite, shp_prewrite):
Simplify unit destruction: just zero efficiency, leave makelost()
etc. to the prewrite callback.
airburst. Leave taking nuke off the plane to caller. Use coord for
coordinate parameters.
(pln_damage): Take nuke off the plane.
(detonate): Destroy the nuke. This is required since arming doesn't
remove nukes from the nuke file anymore (arm.c rev. 1.15).
(nukstr): Hold one nuke instead of a stockpile: replace members nuk_n,
nuk_types by nuk_type, nuk_plane. Add nuk_land for completeness, like
nuk_ship it's not yet used.
(nuke_ca): Update accordingly: replace selectors number and types by
type and plane.
(build_nuke): Update accordingly.
(ndump, nuke): Update accordingly. Output is no longer sorted by
location, and nukes in same location no longer share id. nuke's extra
columns for nuclear plants are repeated for every nuke.
(trade_desc): Update accordingly.
(cede, grab_sect, check_nuke_ok, detonate, trade_nameof): Talk about
nukes instead of nuclear stockpiles.
(arm, disarm): Rewrite, split off new disarm(). Don't remove nuke
from the nuke file on arm. Allow usual plane syntax, not just plane
number. Change second argument from nuke type to nuke number. When
plane is already armed, ignore nuke argument and rearm (broken in
4.2.6).
(tran_nuke): Update for changed struct nukstr, make as similar as
possible to tran_plane. Change syntax to match transport plane.
(player_coms): Update arm, disarm and transport accordingly.
(prnuke, nuk_on_plane): New.
(nuk_add, nuk_delete): Stockpile management, remove.
(ltend, multifire, quite_bigdef, mine, landmine)
(do_loan, prod, printdiff, sell, sona, stre)
(tend, fire_dchrg, vers, work, ac_planedamage)
(ac_shipflak, ask_off, get_mine_dsupport, att_fight)
(ask_move_in_off, detonate, sd, land_gun)
(land_unitgun, lnd_fort_interdiction, lnd_fortify)
(perform_mission, pln_mine, pln_mobcost)
(retreat_ship1, retreat_land1, shp_sweep)
(shp_fort_interdiction, shp_missle_defense)
(new_work, growfood, upd_land, land_repair)
(get_materials, do_mob_ship, do_mob_land)
(load_it, unload_it, prod_plane, produce)
(guerrilla, upd_buildeff, spread_fallout)
(upd_ship, ship_repair, min, dmin, MIN):
Remove min() and dmin() functions and replace
with a MIN macro in misc.h. Remove local MIN
macros and use the new one in misc.h. This
change removes the need for the special
case for _WIN32.
(fuel, look_ship, multifire, mission, sona)
(plane_sona, ef_open, player_accept, player_main)
(ac_dog, att_get_combat, calc_mobcost)
(ask_move_in_off, intelligence_report)
(build_mission_list_type, perform_mission)
(show_mission, use_supply, dodistribute)
(allocate_memory, max, dmax, MAX):
Remove max() and dmax() functions and replace
with a MAX macro in misc.h. Remove local MAX
macros and use the new one in misc.h. This
change removes the need for the special
case for _WIN32.
(doland, detonate, spread_fallout): Use it. With variables, fallout
beyond the capacity of variables (65535) was ignored, except in
doland(), where it saturated at 9999, and spread_fallout, where it
could overflow. Now it always saturates at FALLOUT_MAX.
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, ...
