fix(Core/FindPlayer): The server crashes while shutting down

[PkllonG]

Changes Proposed:

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• Core (units, players, creatures, game systems).
• Scripts (bosses, spell scripts, creature scripts).
• Database (SAI, creatures, etc).

Issues Addressed:

• Closes

SOURCE:

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[PkllonG]

1. Server Shutdowning
2. invoke Guild -> GuildBank -> GuildBank -> Item
3. invoke ItemOwner

Player* Item::GetOwner()const
{
    return ObjectAccessor::FindPlayer(GetOwnerGUID());
}

4. Server Crash.

[Takenbacon]

Do you have a crashlog? Hash map holder shouldn't be returning anything if the Map is empty regardless.

[PkllonG]

Do you have a crashlog? Hash map holder shouldn't be returning anything if the Map is empty regardless.

I put the PR on my server on December 31 last year and it didn't crash since.
According to my analysis, there are several conditions for the crash:1. There must be a guild bank in use. 2. The server must be running for at least a few days. 3. Players with at least a few dozen people.
Then crashes when unloading memory when shutting down the server (.ser re **) and while it doesn't affect anything, it's ugly.

[PkllonG]

Eventually the server crashes here

[Takenbacon]

Eventually the server crashes here

Might be worth reverting your change and seeing, there is nothing unsafe about any of the object accesor code that could lead to a crash, it would be an underlying function as how it's being used. There has also been a lot of memory safety fixes from address sanitizer runs lately that may have fixed it as well.

[PkllonG]

We can close the PR for the time being, and then start the PR if someone crashes here as well.