Seamines and landmines share storage. Sea and bridge span sectors can
hold only sea mines, other sector types only landmines. Sector type
checks were missing or incorrect in several places:
* Seamines under bridge spans were mistaken for landmines in several
places:
- ground combat mine defense bonus, in get_mine_dsupport() and
stre(),
- land units retreating from bombs, in retreat_land1(),
- non-land unit ground movement (commands explore, move, transport,
and INTERDICT_ATT of military), in check_lmines(),
Fix them to check the sector type with new SCT_MINES_ARE_SEAMINES(),
SCT_LANDMINES().
* plane_sweep() mistook landmines for seamines in harbors. Bug could
not bite, because it's only called for sea sectors. Drop the bogus
check for harbor.
* Collapsing a bridge tower magically converted landmines into
seamines. Make knockdown() clear landmines.
Also use SCT_MINES_ARE_SEAMINES() and SCT_LANDMINES() in mine(),
landmine(), lnd_sweep() and lnd_check_mines(). No functional change
there.
Keep checking only for sea in pln_mine(), plane_sweep(),
retreat_ship1(), shp_sweep() and shp_check_one_mines(). This means
seamines continue not to work under bridges. Making them work there
is tempting, but as long as finding seamines clobbers the sector
designation in the bmap, it's better to have them in sea sectors only.
Historical notes:
Mines started out simple enough: you could mine sea and bridge spans,
and ships hit and swept mines in foreign sectors.
Chainsaw 2 introduced aerial mining and sweeping. Unlike ships,
planes could not mine bridge spans. plane_sweep() could sweep
harbors, which was wrong, but it was never called there, so the bug
could not bite.
Chainsaw 3 introduced landmines. The idea was to permit only seamines
in some sector types, and only landmines in the others, so they can
share storage. To figure out whether a sector has a particular kind
of mines, you need to check the sector type. Such checks already
existed in mine, drop and sweep, and they were kept unchanged. The
new lmine command also got the check. Everything else did not.
Ground movement and combat could hit and sweep seamines in bridge
spans. Ships could hit and sweep landmines in harbors.
Empire 2 fixed land unit movement (march, INTERDICT_ATT) not to
mistake seamines for landmines on bridge spans. It fixed ships not to
mistake landmines for seamines. The fix also neutered seamines under
bridge spans: ships could neither hit nor sweep them anymore. Both
fixes missed retreat.
Commit 5663713b (v4.3.1) made ship retreat consistent with other ship
movement.
The automatic supply interface has design flaws that make it hard to
use correctly. Its current uses are in fact all wrong (until commit
0179fd86, the update had a few uses that might have been correct).
Some of the bugs can only bite with land unit capability combinations
that don't exist in the stock game, though.
Automatic supply draws supplies from supply sources in range. Since
that can update any supply source in range, all copies of potential
supply sources a caller may keep can get invalidated. Writing back
such an invalid copy wipes out the deduction of supplies and mobility
from a source, triggering a seqno mismatch oops.
This commit redesigns the interface so that callers can safely keep a
copy of the object drawing the supplies (the "supply sink"). The idea
is to pass the sink to the supply code, so it can avoid using it as
source. The actual avoiding will be implemented in a later commit.
Copies other than the supply sink still need to be eliminated. See
commit 65410d16 for an example.
Other improvements to help avoid common errors:
* Supply functions are commonly used to ensure the sink has a certain
amount of supplies. A common error is to fetch that amount
regardless of how many the sink already has. It's more convenient
for such users to pass how many they need to have instead of how
many to get.
* A common use of supply functions is to get supplies for immediate
use. If that use turns out not to be possible after all, the
supplies need to be added somewhere, which is all too easy to
forget. Many bugs of this kind have been fixed over time, and there
are still some left. This class of bugs can be avoided by adding
the supplies to the sink automatically.
In fact, this commit fixes precisely such bugs in mission_pln_equip()
and shp_missile_defense(): plane interception and support missions,
missile interception (abms), launch of ballistic missiles and
anti-sats could all lose shells, or supply more than needed.
Replace supply_commod() by new sct_supply(), shp_supply(),
lnd_supply(), and resupply_all() by new lnd_supply_all(). Simplify
users accordingly.
There's just one use of resupply_commod() left, in landmine(). Use
lnd_supply_all() there, and remove resupply_commod().
Don't claim "now out of supply" when actually out of mobility.
Don't claim "out of supply" when actually out of shells. A land unit
is out of supply when out of shells, but not necessarily the other way
round.
Reading the sector again invalidates the sector type check. Bug can
currently bite only when the deity redesignates the sector. Call
check_sect_ok() instead.
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.
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.
The old code didn't honor command abortion at the following prompts:
* arm third argument
* deliver fourth argument (also simplify)
* fire third argument
* fly and recon prompt for carrier to land on: pln_onewaymission()
treated abort like empty input, which made planes attempt landing in
the sector.
* lmine second argument
* order d fourth argument
* power c nat(s) argument
* range second argument
* sail second argument
* shutdown both arguments (first one was broken in commit 84cfd670,
v4.3.10, second one never worked).
* tend third argument
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.
(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, mine, landmine, setsector, pln_dropoff): Use it. With
variables, mining beyond the capacity of variables (65535) was
ignored. Now the mines saturate at MINES_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, ...
