Auto-update and shutdown broken on Linux systems

[Finomnis]

I realized that server auto-updates do not work for me.
I found out that the 'shutdown' step of odin does nothing in my docker.

After a little digging, I found out that many linux based systems have trouble handling process names with more than 15 characters.
Reducing the process search to 15 characters fixed the problem for me.

I created a pull request as a change suggestion to fix this problem: #441
I had a little trouble naming stuff so be very welcome to rework this fix suggestion.

[mbround18]

Huh, weird, I can look into the auto update function and thank you for adding an update for #441 ! :)

[Finomnis]

The update itself works, just to clarify. It tries to shut down the server, thinks the server is shut down, runs the update and starts the server again. But because the server never shut down properly, 'starting it' does nothing. Odin reports a successful update, and the new version is on the disk, but in RAM the old process is still running.

Happens consistently on my system.:

$ cat /etc/lsb-release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=20.04
DISTRIB_CODENAME=focal
DISTRIB_DESCRIPTION="Ubuntu 20.04.2 LTS"

$ uname -a
Linux docker 5.4.0-81-generic #91-Ubuntu SMP Thu Jul 15 19:09:17 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux

I'm running portainer, but it should work with normal docker-compose just as consistently:

version: "3"
services:
  valheim:
    image: mbround18/valheim:1.4.3
    container_name: valheim
    restart: always
    stop_grace_period: 1m
    ports:
      - "2456-2458:2456-2458/udp"
    environment:
      - PORT=2456
      - NAME="<...>"
      - WORLD="<...>"
      - PASSWORD="<...>"
      - TZ=Europe/Berlin
      - PUBLIC=1
      - AUTO_UPDATE=1
      - AUTO_UPDATE_SCHEDULE="15 * * * *"
      - WEBHOOK_URL="https://discord.com/api/webhooks/<...>"
    volumes:
      - config:/home/steam/.config/unity3d/IronGate/Valheim
      - server:/home/steam/valheim
      - steamcmd:/home/steam/steamcmd
volumes:
  steamcmd:
  server:
  config:

[Finomnis]

I'm a little scared that if this bug happens, it has the potential to corrupt savegames.
Because the old version runs in RAM but the new assets are already installed on disk (if there are any assets that the game loads from disk), this might cause serious problems. Don't know enough about the inner workings of Valheim though.

[mbround18]

@Finomnis that is a worry, but i can simulate that, most people have been shutting down the valheim instance and starting it again to update it

[Finomnis]

@mbround18 When I tested it again on my server I realized that the has been shutdown successfully message comes way too early, and then I realized I f'd up the PR ... the .is_empty() was replaced with .is_running(), but should have been replaced with ! .is_running().

Will create a bugfix PR.
I sincerely apologize, I am surprised it went through both of our reviews :/

[Finomnis]

@mbround18 Bugfix PR: #448