Relations checking with getrel() often needs a special case for "is
same country". If you forget, you get behavior appropriate for a
neutral foreign country, which is usually very wrong (see commit
16c68eb4 for an example).
Unlike getrel(), relations_with() considers countries allied to
themselves. Less dangerous. In fact, allied behavior is typically
just right, so the special case isn't even needed.
Before, it overwrote '?', '.', ' ' in the bmap with the capitalized
country letter, but only for sectors the player owns. Pretty
harmless, just weird. It can't happen currently, because sharebmap
with self fails with "does not have friendly relations towards you".
Flashing yourself failed with a bogus "not logged on" message for
deities, and a mildly bogus "not a deity or friendly with us" message
for mortals.
Fix by simply permitting it. Not terribly useful, except perhaps for
empire-hub users, but why not.
The second patch hunk fixes a latent bug. Before, rejected deity
flashes led to a bogus "not logged on" message, now they lead to a
"not accepting" message. But deity flashes can't be rejected, so this
doesn't matter.
sendmessage() checked NF_FLASH on two places: when deciding whether to
send the message, and later when telling the player why it didn't send
a flash. This can race with the toggle command as follows: if a flash
could not be sent because the recipient's NF_FLASH was off, and the
recipient toggled it on before the flag was checked again, the flash
command claimed the sender wasn't logged on.
feels_like_helping() case cn == foe is missing in the code it
replaces. No difference in behavior, because:
* cn == foe && cn == friend can't happen. Because you can't get into
ground combat against yourself (assault, attack and paradrop don't
let you), friend != foe for support.
* cn == foe && cn != friend behaves the same: no support.
feels_like_helping() returns 0 because of the explicit case. The
replaced code doesn't support because cn can't be at war with
itself.
Mission execution first builds lists of eligible units, one list per
country. These lists are passed to perform_mission() one by one,
where they get freed.
Bugs:
* unit_interdict() didn't pass the list for the submarine's owner, but
build_mission_list_type() built one. Any submarine movement within
own submarine interdiction mission op areas leaked memory.
* dosupport() passed only lists for countries that actually support
(ally at war with victim), but build_mission_list_type() built lists
for all countries hostile to the victim. Ground combat within
support mission op areas countries that are hostile to one of the
party without actually supporting the other leaked memory.
* perform_mission() failed to free missiles targeting units.
Fixing the latter is straightforward.
Fix the first two by deciding whether a country acts on a mission
trigger before building any lists, in ground_interdict(),
unit_interdict(), dosupport(). Remove the code dealing with that from
build_mission_list_type() and the loops around perform_mission().
lnd_mar() and lnd_mar_one_sector() take an actor argument.
Nevertheless, they sometimes used player->cnum. Fortunately, they are
the same: all callers pass current player for actor. Normalize to
actor for consistency.
Land units pay a mobility penalty when marching into a non-old-owned
sector without sector mobility, to slow them down in newly taken
sectors. Attacking land units pay this penalty regardless of sector
mobility.
When attacking out of an allied sector, the penalty was computed as if
the land unit was owned by that ally. Attacking sectors old-owned by
that ally was too cheap, and taking back one's own was too expensive.
Broken since attacking land units pay the "newly taken" mobility
penalty: commit 2e693275, v4.3.6.
When an attacking sector got lost while the player was at a prompt,
and the new owner was allied to the player, the server got confused:
1. If the sector attacked with mil, the server let the ghost mil
attack, but not occupy.
2. If the sector was allied, the server reported the sector loss and
land units dropping out of the attack, but claimed the lost sector was
yours.
Fix 1. by dropping sectors from attack when they change owner away
from the player, regardless of relations. Side effect: also drops any
surviving land units there. Before, they dropped out only if the new
owner wasn't allied to the player. That change's okay.
Fix 2. the obvious way: change the messages.
Broken in 4.0.0.
SLOW_WAR has issues:
* The check whether the attacker old-owns the attacked sector is
broken, because att_abort() uses sect.sct_oldown uninitialized.
Spotted by the Clang Static Analyzer.
* Its implementation in setrel() is somewhat scary. It's actually
okay, because that part of setrel() only runs within decl(). Other
callers don't reach it: update_main() because player->god != 0
there, and the rest because they never pass a rel < HOSTILE.
* Documentation is a bit vague.
SLOW_WAR hasn't been used in a public game in years. Fixing it is not
worth it, so remove it instead.
"rm -r" prompts for read-only files when stdin is a tty. Probably
broken since we install builtin configuration read-only, in commit
b4161cd7, v4.3.0.
Move "done" message to the right place. Broken in commit 70c03561,
v4.3.12.
The previous commit's message claims the race can lead to duplicated
output, use after free, then double-free. That's correct only up to
the use after free. There is no double-free.
Heap corruption (double-free?) has been observed in Changeling,
though. Player logged in (still in sanctuary), map #, crashed within
removecc()'s free(io->data). Partial backtrace:
raise () from /lib64/libc.so.6
abort () from /lib64/libc.so.6
__libc_message () from /lib64/libc.so.6
malloc_printerr () from /lib64/libc.so.6
removecc (ioq=0x251fd10, cc=468) at ../src/lib/gen/ioqueue.c:350
ioq_dequeue (ioq=0x251fd10, cc=468) at ../src/lib/gen/ioqueue.c:135
io_output (iop=0x251fc90, wait=1) at ../src/lib/empthread/io.c:231
recvclient (cmd=0x258d8e0 "", size=1024) at ../src/lib/player/recvclient.c:82
getcommand (combufp=0x2557068 "map #1") at ../src/lib/player/empdis.c:84
I haven't been able to reproduce.
To hopefully catch ioqueue going south earlier, make ioq_dequeue()
oops when it can't dequeue as many bytes as requested.
Move call of ioq_makeiov() to its use, because calling it before
empth_select() is racy, as follows.
Player thread flushes output by calling io_output(player->iop, 1).
io_output() sets up iov[] to point to queued output. empth_select()
blocks on output.
Another thread sends a C_FLASH or C_INFORM message to this player.
This calls io_output(p->iop, 0). The output file descriptor has
become writable since the player thread blocked on it, so some output
gets written and dequeued.
The player thread resumes, writes out iov[] and dequeues. Any output
already written by the other thread gets duplicated. If the other
thread's dequeue operation freed struct io buffers, there's use after
free followed by double-free.
If defenders get to shoot before bombs are dropped, they surely get to
shoot before time-consuming missions like sweep and sonar.
Sweep and sonar used to happen after air defense, but before flak and
interception. Air defense existed from Chainsaw 3 to v4.3.19.
plane_sona() prints an empty line to make sonar contacts stand out.
Move it so the contact is visually "attached" to the right sector,
like this:
flying over sea at 15,-3
Sonar contact in 15,-3
sub #3 13,-3
flying over sea at 13,-3
Before:
flying over sea at 15,-3
Sonar contact in 15,-3
sb submarine (#3) 13,-3
flying over sea at 13,-3
struct trdstr members trd_x, trd_y are used only for teleporting
trades. For others, trad() wrote garbage coordinates to the trade
file. They weren't used except by xdump. Fortunately, even there
they're visible only to deities.
Write invalid coordinates instead. Do that in set() as well, so that
coordinates are valid only when we have a teleport destination.
Spotted by the Clang Static Analyzer.
It showed unit coordinates in unit's coordinate system instead of the
actor's. Fortunately, they're the same, since it is reachable only
for non-zero actor, only shp_nav_one_sector(), lnd_mar_one_sector()
and sail_nav_fleet() pass that, and even deities can't navigate
foreign ships or march foreign land units.
Limited since Chainsaw 2 so that the radar map fits into a world map
without clipping, i.e. its diameter neither exceeds WORLD_X / 2 nor
WORLD_Y. Maybe range exceeding that triggered bugs then. It doesn't
now, and it makes no sense.
The limit never applied to automatic bmap update from ship radar.
