Merge lp:~widelands-dev/widelands/bug-1831583-fri02 into lp:widelands

[Benedikt Straub]

Add some sleep time to costly loops in fri02 to prevent freezing

This is a Lua problem. gdb shows that masses of new Lua objects are created, and Lua doesn´t care to release the memory again. Hopefully, some additional sleep() will give the game and the garbage collector time to catch up.

I don´t want to fix this by increasing the base sleep time or the objective will be marked done only after an enormous delay.
Another way to fix the bug while perhaps improving performance would be to move the checks to C++, but I feel bad about having such specialised functions there.

[bunnybot (widelandsofficial)]

Continuous integration builds have changed state:

Travis build 5152. State: errored. Details: https://travis-ci.org/widelands/widelands/builds/541383420.
Appveyor build 4934. State: success. Details: https://ci.appveyor.com/project/widelands-dev/widelands/build/_widelands_dev_widelands_bug_1831583_fri02-4934.

[GunChleoc (gunchleoc)]

We have these sleep times a lot in our Lua scripts for checking loops, so let's have it :)

@bunnybot merge

review: Approve

[bunnybot (widelandsofficial)]

Refusing to merge, since Travis is not green. Use @bunnybot merge force for merging anyways.

Travis build 5152. State: errored. Details: https://travis-ci.org/widelands/widelands/builds/541383420.

[hessenfarmer (stephan-lutz)]

regarding these objectives a 1 second delay does not matter at all. for me even 2 or 3 seconds would be hardly recognizable by the player. so we could even go up with the sleep if necessary.

[hessenfarmer (stephan-lutz)]

Wow 3 times the inputqueues faiklure in one build seems to be a new record.

@bunnybot merge force

review: Approve

=== modified file 'data/campaigns/fri02.wmf/scripting/mission_thread.lua'
--- data/campaigns/fri02.wmf/scripting/mission_thread.lua	2019-03-29 18:29:54 +0000
+++ data/campaigns/fri02.wmf/scripting/mission_thread.lua	2019-06-04 18:05:55 +0000
@@ -33,6 +33,7 @@
 
 function check_empire()
    while true do
+      sleep(1000)
       for idx,field in ipairs(all_fields) do
          sleep(5)
          local p1c = false
@@ -272,9 +273,9 @@
    while not p3.defeated do sleep(4513) end
    set_objective_done(o)
 
-   -- If the barbarians already defeated Murilius – well done
+   -- If the barbarians already defeated Murilius – well done.
    -- Otherwise, Murilius provokes Reebaud into ordering the player to conquer his entire colony
-   -- (merely defeating the Empire isn’t enough)
+   -- (merely defeating the Empire isn’t enough).
    -- We don't bother to check water, walkable-only and other useless terrains.
    -- That would be really too much to ask from our poor player, now wouldn't it?
    if not p2.defeated then
@@ -285,6 +286,7 @@
       o = add_campaign_objective(obj_defeat_murilius)
       local def = false
       while not def do
+         sleep(1000)
          def = true
          for idx,field in ipairs(useful_fields) do
             if field.owner == p2 then