Prevent crashes and bad behavior when vehicle updates invalidate the vehicle list #31348
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kevingranade
changed the title
mlangsdorf
approved these changes
Jun 11, 2019
ifreund
added
<Bugfix>
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Summary
SUMMARY: None
Purpose of change
The previous change #31330 had a logic error in that the list returned by map::get_vehicle() is invalidated in several situations, which could have lead to failing to update vehicles, or dereferencing orphaned pointers.
Describe the solution
Have movement methods return nullptr when the vehicle they are updating may have invalidated the list, either by being destroyed or by damaging another vehicle. Then when the calling function detects a returned nullptr, refresh the vehicle list.
Describe alternatives you've considered
All of this code needs to be seriously rethought, but this adresses the issue for now.