Builtin auth handler: Speed up file writing (#7252)

diff --git a/builtin/game/auth.lua b/builtin/game/auth.lua
index 74eb6ae88f71665166591ca1d75a23c92f2fd843..19af8db73dfa9ad7d88ed93686f1fcc4914bc16d 100644 (file)
--- a/builtin/game/auth.lua
+++ b/builtin/game/auth.lua
@@ -67,13 +67,13 @@ local function save_auth_file()
                assert(type(stuff.privileges) == "table")
                assert(stuff.last_login == nil or type(stuff.last_login) == "number")
        end
-       local content = ""
+       local content = {}
        for name, stuff in pairs(core.auth_table) do
                local priv_string = core.privs_to_string(stuff.privileges)
                local parts = {name, stuff.password, priv_string, stuff.last_login or ""}
-               content = content .. table.concat(parts, ":") .. "\n"
+               content[#content + 1] = table.concat(parts, ":")
        end
-       if not core.safe_file_write(core.auth_file_path, content) then
+       if not core.safe_file_write(core.auth_file_path, table.concat(content, "\n")) then
                error(core.auth_file_path.." could not be written to")
        end
 end