snxtsct() and snxtitem() fail when the condition argument is bad.
satmap() didn't check for failure. Due to the way snxtsct() and
snxtitem() work, bad condition arguments were reported and otherwise
ignored.
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.
satdisp_sect() updated the in-memory bmap, but failed to write the
updates to disk. Its callers already update bmap from other sources,
so move this update there, and connect it to the existing write back.
With RAILWAYS, highway-like sectors double as rail. They need to be
at least 5% efficient to be operational, and then they additionally
extend rail into adjacent sectors that are at least 60% efficient.
New opt_RAILWAYS, SCT_HAS_RAIL(), sct_rail_track(). Update
sector_mcost(), bp_neighbors(), lnd_mar_one_sector() for RAILWAYS
mobility rules. Update sinfra(), spyline(), satdisp_sect() to show
rail track instead of rail infrastructure for RAILWAYS.
New virtual sector selector track, implemented by nsc_sct_track().
The correct method to compute indexes into a map buffer for a struct
range is deltx(), delty().
path() used deltax(), deltay() instead, which yield correct results
only for indexes up to half the world size. Pathes spanning larger
areas were screwed up.
sona(), radmap2(), satmap() also used deltax(), deltay(), but only
with arguments where those yield correct results.
draw_map() used xnorm(), ynorm() instead, which is correct, but less
clear and less efficient.
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 value of diffx() had the wrong sign when the arguments differed by
WORLD_X / 2. Same for diffy() and WORLD_Y / 2. satmap() used them to
find the vector from map center to ship or land unit to put on the
map, and got incorrect values for ships and land units directly
opposite to the center in x or y. The bug made satmap() read a
pointer out bounds of its malloced radbuf[], and then write through
that with unpredictable consequences.
Broken in 4.2.12. The original bug was in Empire 1.1: it
miscalculated where to put ships on the map (no crash). An incomplete
fix for radmap() and satmap() appeared in Chainsaw 2 (still no crash).
radmap() got fixed correctly in Chainsaw 3, but satmap() was
forgotten. That one got "fixed" in 4.2.7, and again in 4.2.12, but
both "fixes" were flawed and could crash.
Fix by backing out the flawed fixes and adopting the fix from radmap()
instead.
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.
satdisp_sect() and satdisp_units().
(satmap): Call only satdisp_sect(). No functional change.
(aircombat): Call both, and call satdisp_units() even over sea. This
lets spy planes spot surface ships at sea. Closes#906035.
(map_char): New.
(draw_map): Use it. Wilderness and plains owned by other players are
now displayed as '?'.
(radmap2): Display wilderness and plains as '?'.
(satmap): Call satdisp() for all sectors owned by other players.
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.
