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.
The old code used getstarg() to get an argument with a different
prompt than snxtitem() uses, then passed the value to snxtitem()
unchecked. If the player aborts, getstarg() returns a null pointer,
and snxtitem() prompts again. Affected:
* load/lload plane/land third argument; load_plane_ship(),
load_land_ship(), load_plane_land(), load_land_land()
* bomb, drop, fly, paradrop, recon and sweep second argument;
get_planes()
* tend and ltend second and fourth argument; ltend(), tend(),
tend_land()
* mission second argument; mission()
Fix by making snxtitem() taking a prompt argument, null pointer
requests the old prompt.
Use that to simplify multifire() and torp(). Change the other callers
to pass NULL.
This takes care of a number of bugs / inconsistencies:
* Submarines with zero mobility could interdict. Change to require
positive mobility.
* Submarines with zero firing range could not interdict. Fix by
dropping the test from perform_mission(). No ships in the stock
game are affected.
* Submarines without capability torp could fire return torpedoes and
interdict. Stock sbc, nm and msb were affected by the return fire
bug. Closes bug#950936.
* Shell resupply bugs: quiet_bigdef(), fire_torp() and
perform_mission() resupplied before checking all other requirements
and could thus get more shells than actually needed.
torp() no longer resupplies shells. It's hardly worth the bother, and
fire doesn't do it either.
anti_torp() required line of sight and used gun range for all kinds of
return fire. Require line of sight only for torpedoes, not for gun
fire and depth charges. Use torpedo range for torpedoes, gun range
for gun fire and depth charges.
This takes care of a number of bugs / inconsistencies:
* Ships with zero firing range could return fire and fire support, but
not fire actively or interdict. Fix by testing for gun limit
instead in multifire() and mission(). No ships in the stock game
are affected.
* Required gun crew was inconsistent: multifire() let N military fire
max(1,floor(N/2)) guns for active fire. Ditto perform_mission() for
interdiction. quiet_bigdef() let them fire N guns for returning gun
fire. Ditto sd() for firing support and firing at boarding parties.
fire_dchrg() let them fire floor(N/2) for returning fire to
torpedoes. Unify to let N military fire floor((N+1)/2) guns.
* Shell use was inconsistent: sd() and perform_mission() used one
shell per gun, everything else one per two guns. Unify to one shell
per two guns.
* Shell resupply bugs: multifire() got two shells regardless of actual
ammo use. quiet_bigdef() got one shell (but use_ammo() uses only
one, which is a bug). sd() and perform_mission() resupplied before
checking all other requirements and could thus get more shells than
actually needed.
Before 4.0.6, depth charges required no guns, one military, did damage
like shell fire from two guns, and used two shells. Missions were not
quite consistent with that (bug). 4.0.6 changed depth charges to work
exactly like shell fire (but without updating documentation
accordingly): require guns and gun crew, non-zero firing range, scale
damage and ammunition use with guns.
Go back to the old model, but with damage like three guns, to avoid
changing the stock game's dd now (three gun damage for two shells).
Stock game's af changes from two gun damage for one shell, and nas
from four gun damage for two shells.
Factor out common depth-charging code into shp_dchrg().
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.
(use_ammo, eta_calc, torp, fire_torp, perform_mission, retreat_ship1)
(shp_sweep, shp_nav_one_sector, cost_ship): Use it.
(perform_mission): Fix mobility cost of torpedo: charged full sector
cost instead of half.
(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.
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, ...
instead of declaring them all over the place. This uncovered type
errors:
(s_p_etu, adj_update): Defined long, sometimes declared int. Kills
big endian machines where sizeof(long) != sizeof(int). Change to
int.
(set_option, delete_option, optstrset, intset, floatset, doubleset,
longset, optionset, optiondel, worldxset): Change linkage to static.
effect. Replace calls by struct assignment where possible. Replace
clear buffer, copy string to buffer by strncpy(). Use assignment to
clear when that's clearer. Replace overlapping copy through bounce
buffer by memmove(). Replace rest by standard memset() and memcpy().
Also use sizeof() instead of literal array sizes for robustness, and
instead of symbolic array sizes for clarity.