Trade ships are now enabled when a ship type with capability trade
exists. No such type exists by default; to enable trade ships,
deities have to customize table ship-chr.
Before, trade ship types were ignored when option TRADESHIPS was
disabled. Except for xdump ship-chr, which happily dumped unusable
trade ship types.
Only trade ships can be auto-scuttled. orde() rejects scuttle orders
for other ships. scuttle_it() double-checks, but gets the test wrong:
it rejects only when opt_TRADESHIPS is enabled. Fix that. While
there, make it oops on inadmissible ships.
Destinations are no longer treated as unreachable when the best path
is longer than 99 characters. Instead, consider up to 1023 characters
of the best path.
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.
No functional change, because the value of rel only matters when
sectp->sct_own != sp->shp_own, and then it's the same as before.
The new value of rel permits simplifying sectp->sct_own == sp->shp_own
|| rel >= FRIENDLY to just rel >= FRIENDLY.
Oops when a stale copy is written back, i.e. the processor was yielded
since the copy was made. Such bugs are difficult to spot. Sequence
numbers catch them when they do actual harm (they also catch different
bugs). Generation numbers catch them even when they don't.
New ef_generation to count generations. Call new ef_make_stale() to
increment it whenever the processor may be yielded.
New struct emptypedstr member generation. To conserve space, make it
a bit-field of twelve bits, i.e. generations are only recorded modulo
2^12. Make sure all members of unit empobj_storage share it. It is
only used in copies; its value on disk and in the cache is
meaningless. Copies with generation other than ef_generation are
stale. Stale copies that are a multiple of 2^12 generations old can't
be detected, but that is sufficiently improbable.
Set generation to ef_generation by calling new ef_mark_fresh() when
making copies in ef_read() and ef_blank(). nav_ship() and
fltp_to_list() make copies without going through ef_read(), and
therefore need to call ef_mark_fresh() as well. Also call it in
obj_changed() to make check_sect_ok() & friends freshen their argument
when it is unchanged.
New must_be_fresh() oopses when its argument is stale. Call it in
ef_write() to catch write back of stale copies.
Factor unit_drop_cargo() out of scra(), scuttle_ship(),
scuttle_land(), fix it up:
* Some messages were sent as bulletins instead of printing them.
* Nukes were always destroyed. They're now treated exactly like other
cargo.
* scuttle destroyed some cargo silently, and listed other cargo as
"scuttled". It now simply lets unit_update_cargo() running from
carrier prewrite callbacks list all cargo "lost".
Simplify its callers. scuttle_ship() and scuttle_land() are now
trivial, inline and remove.
When called from the scuttle command, scuttle_tradeship() asks for
confirmation when scuttling doesn't pay. When called from the autonav
code, it can't ask. Change it to fail then, and use that in
nav_ship() to avoid scuttle where it doesn't pay. Also simplify some.
The abstract idea of tying ships and land units to a logistical tether
is sound, the concrete implementation as option FUEL is flawed. It
adds too much busy-work to the game to be enjoyable. It hasn't been
enabled in a public game for years. The code implementing it is ugly,
repetitive, and a burden to maintain.
Remove selector fuel from ship_ca[] and land_ca[], and selectors
fuelc, fuelu from mchr_ca[] and lchr_ca[]. Remove fields fuelc, fuelu
from ship.config and land.config.
Remove command fuel from player_coms[].
Deprecate edit key 'B' in doship(), dounit(), and don't show it in
pr_ship(), pr_land().
Drop opt_FUEL code from build_ship(), shi(), sdump(), ship_damage(),
show_ship_stats(), do_mob_ship(), nav_ship(), build_land(), land(),
ldump(), land_damage(), show_land_stats(), do_mob_land(),
resupply_all(), resupply_commod(), get_minimum(), has_supply(),
unit_list(), vers().
Remove opt_FUEL, fuel_mult, struct shpstr member shp_fuel, struct
mchrstr members m_fuelc and m_fuelu, M_OILER, struct lndstr member
lnd_fuel, struct lchrstr members l_fuelc and l_fuelu, fuel(), and
auto_fuel_ship().
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.
must be valid. Oopses on bad direction characters.
(pathtoxy, ac_encounter): Bad direction characters used to lead to bad
array subscript and potential disaster.
(pathrange, path): Stop on DIR_STOP as well as on bad direction
characters. This is just for consistency with other code; DIR_STOP
should occur only last in a path here.
(sail_nav_fleet, nav_ship): No change except for the oops.
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.
capacities to straight arrays. Users now subscript the array instead
of calling vl_find() or walking the variable data structure.
(mchr, lchr): Initializers adapted.
(vl_find): No longer used. Remove file.
item types instead of mnemo characters in shpstr members shp_tstart[]
and shp_tend[].
(com_num): No longer used, remove.
(orde): Simplify swap code.
(prhold): New, factored out of qorde().
