Software /
code /
prosody
File
util/presence.lua @ 10571:cfeb0077c9e9
net.server_epoll: Avoid concatenating buffer with single item
Saves creating a string that'll be identical to buffer[1] anyways, as
well as a C function call. Depending on Lua version and length of the
string, this could be reusing an interned string, but a longer one would
probably be duplicated for no reason.
Having exactly one item in the buffer seems like it would be fairly
common, but I have not done an extensive study. If opportunistic writes
are enabled then it will be even more likely.
This special case could be optimized like this in table.concat but it
does not look like it is.
author | Kim Alvefur <zash@zash.se> |
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date | Sat, 28 Dec 2019 06:18:58 +0100 |
parent | 8885:d4f5d47f874d |
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-- Prosody IM -- Copyright (C) 2008-2010 Matthew Wild -- Copyright (C) 2008-2010 Waqas Hussain -- -- This project is MIT/X11 licensed. Please see the -- COPYING file in the source package for more information. -- local t_insert = table.insert; local function select_top_resources(user) local priority = 0; local recipients = {}; for _, session in pairs(user.sessions) do -- find resource with greatest priority if session.presence then local p = session.priority; if p > priority then priority = p; recipients = {session}; elseif p == priority then t_insert(recipients, session); end end end return recipients; end local function recalc_resource_map(user) if user then user.top_resources = select_top_resources(user); if #user.top_resources == 0 then user.top_resources = nil; end end end return { select_top_resources = select_top_resources; recalc_resource_map = recalc_resource_map; }