Calling minetest.chat_send_all in minetest.register_on_newplayer causes hanging

[rubenwardy]

Noticed while developing my capture the flag subgame.

Pressing ctrl+c on server prints

 ^C20:24:09: INFO: sigint_handler(): Ctrl-C pressed, shutting down.

But nothing else. Server doesn't close. No error messages.

Minimal example, install as init.lua in a mod:

minetest.register_on_newplayer(function(player)
    minetest.chat_send_all(" has joined")
end)

No hanging when using minetest.register_on_joinplayer.

[rubenwardy]

Back trace of client: https://gist.github.com/rubenwardy/b9bbb98d89f345a7d083
Server is in "usleep" whenever I backtrace it.
Discovered in cd4324e

[rubenwardy]

No longer a problem on latest master.

[nerzhul]

I fixed a deadlock similar as you show yesterday

[rubenwardy]

Awesome. Thank you very much.