Code dealing with money mixes int and long pretty haphazardly.
Harmless, because practical amounts of money fit into int on any
machine capable of running the server. Clean up anyway.
meltitems() computes #items * etus per update * fallout in type long.
Theoretical maximum is ITEM_MAX * etus * FALLOUT_MAX = 99980001 *
etus. Can overflow 32 bits for etus > 21. Has been broken since the
introduction of fallout in KSU.
Compute the product in double instead.
Code dealing with reserves mixes int and long pretty haphazardly.
Harmless, because practical reserves fit easily on any machine capable
of running the server. Clean up anyway.
Code dealing with counting people mixes int and long pretty
haphazardly. Harmless, because practical populations fit into int
easily on any machine capable of running the server. Clean up anyway.
As long as symbol_by_value(), show_capab() and togg() support only
int, flags need to fit into int.
Not a problem in practice, because no machine capable of running
Empire has int narrower than 32 bits, and 32 bits suffice.
Some flags members are long instead of int: struct lchrstr member
l_flags, struct natstr member nat_flags, struct mchrstr member m_flags
are long. Waste of space on machines with long wider than int.
Change them to int.
Rearrange struct lchrstr and struct natstr to avoid holes.
ef_ensure_space() oopses on negative ID, but succeeds anyway. edit()
proceeds to ef_write(), which neglects to check for negative ID.
Since the ID isn't in the cache, it then passes a NULL old element to
callback prewrite(), which crashes.
Fix ef_ensure_space() to fail on negative ID. Commit 5173f8cd
(v4.3.0) made it oops, but neglected to make it fail.
Fix ef_write() to oops and fail on negative ID.
ef_write() still passes NULL old element to prewrite() when the ID
isn't in the cache. Doesn't actually happen, because we use
prewrite() callbacks only with fully cached tables. Fragile. Make
ef_open() fail when that assumption is violated.
Newly built ships and land units are given to the player, planes and
nukes to the sector owner. Matters only for deities, because only
deities can build in foreign sectors. Stupid all the same.
This has always been inconsistent. Empire 1 gave ships and nukes to
the player, and planes to the sector owner. Chainsaw 3 added land
units, and gave them to the player. Empire 2 changed build to give
nukes to the sector owner.
Building doesn't work when the unit built is given to POGO, because
giving a unit to POGO destroys it. When build gives to the sector
owner, deities can't build in unowned sectors. When build gives to
the player, POGO can't build at all. That's more limiting, so change
build to always give to the sector owner.
We seed it with value of time(). It's the traditional way, but it
provides only a few bits of effective entropy when an attacker has a
rough idea when the program started.
Instead, seed with a kernel random number. If we can't get one, fall
back to a hash of gettimeofday() and getpid(). This should happen
only on old systems or Windows. Far worse than a kernel random
number, but far better than using time().
Note that fairland used to seed with time() + getpid() until commit
331aac2a (v4.2.20) dropped the getpid(), claiming it didn't improve
the randomness. Perhaps it didn't under Windows then, but it
certainly did elsewhere, so it was a regression.
random() may yield different pseudo-random number sequences for the
same seed on another system. For instance, at least some versions of
MinGW provide a random() in -liberty that differs from traditional BSD
(see commit c8231b12). Rather inconvenient for regression testing.
MT19937 Mersenne Twister is a proven, high-quality PRNG. Actual code
is reference code provided by the inventors[*]. Quick tests show
performance comparable to random().
Like random(), MT is not cryptographically secure: observing enough of
its output permits guessing its state, and thus its future output. I
don't think players can do that.
Drop the copy of BSD random() we added for Windows.
Like the previous commit, this changes the server's die rolls, and
makes fairland create a different random map for the same seed. Update
expected smoke test results accordingly.
[*] mt19937ar.sep.tgz downloaded from
http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/MT2002/emt19937ar.html
"random() % n" is sound only when n is a power of two. The error is
hardly relevant in Empire, because random() yields 31 bits, and our n
are always much smaller than 2^31. Fix it anyway.
Use smallest the 2^m >= n instead of n, and discard numbers exceeding
n.
Bonus: faster for me even in the worst case n = 2^m+1.
Like the recent change to damage(), this changes some of the server's
die rolls, only this time the effect is pretty pervasive. Worse,
fairland now creates a completely different random map for the same
seed. Update expected smoke test results accordingly.
Turns damage() into a one-liner.
damage() now uses random() % 32768 in chance() instead of random() %
100 inline, therefore can round differently for the same pseudo-random
number. Update expected smoke test results accordingly.
Aside: "random() % n" distributes evenly only when n is a power of
two. 100 isn't. However, because random() yields at least 31 bits,
and 100 is so much smaller than 2^31, the error is vanishingly small.
Change chance in percent lnd_retreat - lnd_effic - 1 to lnd_retreat -
lnd_effic. It's been that way since Empire 2, but I can't bring
myself to document the silly -1.
"info morale" wasn't updated when the retreat chance was changed in
Empire 2. Fix that.
The tech center doesn't have enough workers to use all materials in
some updates. How much get made depends on a die roll then. Tech
variations are inconvenient because they ripple through the rest of
the smoke test.
Too easily upset by random variations. Kill them off with anti after
two updates, and occupy with a few more military.
While there, enlist the military in a highway rather than an lcm
plant.
News reporting merges news items into recent items with same contents.
For that purpuse, we keep a small cache of recent items. When a new
item can't be merged into an item in the cache, the oldest item gets
evicted to make space for the new one.
ncache() evicts the first item with the smallest timestamp (struct
nwsstr member nws_when). Timestamps are in seconds, therefore clashes
are common, and eviction depends on exact timing. Such indeterminism
can make the smoke test fail.
Moreover, ncache() assumes timestamps cannot exceed 0x7fffffff. If
they do, it always evicts the slot 0. They will in 2038.
Fix by evicting round robin. This always evicts the oldest item.
The airfield is a sector taken from player 8. How many updates it
takes to convert is highly variable. If it converts late, the
airfield may not be constructed in time. This is currently the case
for me.
Move the airfield to a more dependable sector.
For me, the smoke test now fails frequently, because of differences in
news. To be fixed next.
Just a smoke test so far, extracted from src/scripts/nightly/. This
makes the existing smoke test more easily accessible. Noteworthy
differences:
* Instead of patching the code to make output more stable, postprocess
the output to normalize it.
* Compare actual results to expected results instead of the previous
test run's results.
* Much faster. The old test harness used sleep liberally to "ensure"
things always happen in the same order.
Known shortcomings:
* The smoke test hangs when the server fails to complete startup, or
fails to terminate.
* Normalization of xdump hardcodes columns instead of getting them
from xdump meta.
* Normalization of time values in xdump is an ugly hack.
* xdump meta column type isn't normalized. Actual values can vary
between systems, because the width of enumeration types is
implementation-defined. The smoke test works only when they're
represented as int, which is the case on common systems.
* Currently expected to work only with thread package LWP and a
random() that behaves exactly like the one on my development system,
because:
- Thread scheduling is reliably deterministic only with LWP
- The PRN sequence produced by random() isn't portable
- Shell builtin kill appears not to do the job in MinGW
- The Windows server tries to run as service when -d isn't
specified
Further work is needed to address these shortcomings.
Getting C programs behave exactly the same on all systems is hard.
We'll likely run into system-dependent differences that upset the
smoke test. Floating-point computation seems particularly vulnerable.
Instead of updating src/scripts/nightly/ to use "make check", retire
it. It hasn't been used in quite a while. Investing more into our
homegrown auto-builder doesn't make sense, as canned auto-builders
such as Travis CI and Jenkins are readily available.
The shell scripts src/scripts/nightly/tests/?? become Empire batch
files tests/smoke/. The shell scripts are actually shell boilerplate
around Empire batch files. To make sure git recognizes the move, this
commit moves them unchanged. tests/smoke-test strips the boilerplate
before it feeds the batch files to the client. The next commit will
get rid fo that.
Commit ee01ac19 (v4.3.23) enlarged player member hostaddr from 32 to
46 characters, but missed natstr member nat_hostaddr. player_main()
copies hostaddr to nat_hostaddr. Can overrun the destination, but
fortunately just into nat_hostname.
Impact:
* Can makes praddr() print only a suffix of the address. Used by play
command, for player messages during login and logout, and for
logging.
* Can make player_main()'s test for "same address as last time" fail,
causing extra "Last connection" messages.
* Matching against econfig key privip is not affected.
* Journal event login is not affected.
Due to a typo, shp_missile_interdiction() picks the admissible target
with highest efficiency instead of the one with highest efficiency *
build cost.
Broken in commit cd8d7423, v4.3.8.
setsector() and setres() continue after check_sect_ok() fails.
Clobbers the updates that made check_sect_ok() fail, triggering a
seqno mismatch oops.
Commit 04a332a8 (v4.3.27) claimed to fix this, but actually only
suppressed the generation oops.
