[Wesnoth-dev] KISS Solution to user campaign stability problems

[David White]

We obviously can't ship 1.0 with the possibility of users connecting to 
the campaign server, and downloading campaigns which makes it impossible 
for them to start the game.

I have thus come up with a solution that I'm currently testing, that I 
think works nicely, and simply. It reduces the generality of the engine 
slightly, but I think it gives us the stability we need for a 1.0 release.

The solution is to remove the {~data/campaigns} reference in the 
game.cfg file. Instead, the game now reads data/game.cfg and then reads 
each file in the pattern ~data/campaigns/*.cfg, and appends them to the 
config object. If a user campaign has any errors, it will not be loaded, 
and an error message will be displayed stating that the campaign didn't 
load properly. A failed user campaign load will not affect caching, and 
thus the message about a campaign not loading will only be displayed 
again the next time the user changes their data.

The top-level [units] tags are merged together into one [units] tag 
immediately after reading all the files. Also, since the user campaigns 
are now read after the core unit definitions, user campaigns cannot 
redefine core units. There are plenty of alternatives for user campaigns 
that want to make units that appear identical to core units yet somehow 
act differently.

Any comments on this change are welcome. I plan to check it in shortly 
if my testing goes well.

David