[3.5-dev] New refactored FOV crashes

[PowerWyrm]

See this commit: 9d48405fa5669b2419067dd0522512c5d5a77237 (Detect and work around the 'knight's move' LOS hack when doing FOV).

Calls to cave_iswall(c, x + something, y + something) are suspicious for two reasons: first, the function declaration is cave_iswall(struct cave *c, int y, int x), which implies that y should go before x; second, the two parameters surely can go out of bounds when you inspect a grid that is near the border of the level, so maybe add some bound checking somewhere.

[PowerWyrm]

It seems that the problem is more severe...

Now I got random crashes when changing levels. I suspect an illegal access to cave->info somewhere. On my local copy of the source, I'm gonna do three things:
- remove the byte_256 hack on cave->info and use byte_wid instead (I don't see anywhere in the source why cave->info has width 256 instead of DUNGEON_WID, it's probably a leftover from old code)
- add access functions to all CAVE_XXX flags and put an assert(in_bounds) in them
- fix asserts I'll get by putting in_bounds checks where the code lacks them

[AnonymousHero]

Have you tried running under Valgrind?

[PowerWyrm]

I finished refactoring the cave->info access code, and it seems that the only faulty code is the one mentioned in my first post ('knight's move' rule when updating FOV): calls to cave_iswall() are done with out of bounds coordinates when near the border of the level. Adding some bounds checking fixed the crash problems.