net.server_select: remove unused one-letter loop variables [luacheck]

[prosody.git] / net / server_select.lua

diff --git a/net/server_select.lua b/net/server_select.lua
index d9826c02e3188003963c1c87b5f7616a2f344368..85730e73c4d2d6c216d9ec062ab97926b6cf56a2 100644 (file)
--- a/net/server_select.lua
+++ b/net/server_select.lua
@@ -38,7 +38,6 @@ local coroutine = use "coroutine"
 
 --// lua lib methods //--
 
-local os_difftime = os.difftime
 local math_min = math.min
 local math_huge = math.huge
 local table_concat = table.concat
@@ -89,6 +88,7 @@ local _socketlist
 local _closelist
 local _readtimes
 local _writetimes
+local _fullservers
 
 --// simple data types //--
 
@@ -103,6 +103,7 @@ local _readtraffic
 local _selecttimeout
 local _sleeptime
 local _tcpbacklog
+local _accepretry
 
 local _starttime
 local _currenttime
@@ -131,6 +132,7 @@ _socketlist = { } -- key = socket, value = wrapped socket (handlers)
 _readtimes = { } -- key = handler, value = timestamp of last data reading
 _writetimes = { } -- key = handler, value = timestamp of last data writing/sending
 _closelist = { } -- handlers to close
+_fullservers = { } -- servers in a paused state while there are too many clients
 
 _readlistlen = 0 -- length of readlist
 _sendlistlen = 0 -- length of sendlist
@@ -142,6 +144,7 @@ _readtraffic = 0
 _selecttimeout = 1 -- timeout of socket.select
 _sleeptime = 0 -- time to wait at the end of every loop
 _tcpbacklog = 128 -- some kind of hint to the OS
+_accepretry = 10 -- seconds to wait until the next attempt of a full server to accept
 
 _maxsendlen = 51000 * 1024 -- max len of send buffer
 _maxreadlen = 25000 * 1024 -- max len of read buffer
@@ -210,6 +213,7 @@ wrapserver = function( listeners, socket, ip, serverport, pattern, sslctx ) -- t
                                socket = nil;
                        end
                        handler.paused = true;
+                       out_put("server.lua: server [", ip, "]:", serverport, " paused")
                end
        end
        handler.resume = function( )
@@ -220,7 +224,9 @@ wrapserver = function( listeners, socket, ip, serverport, pattern, sslctx ) -- t
                        end
                        _readlistlen = addsocket(_readlist, socket, _readlistlen)
                        _socketlist[ socket ] = handler
+                       _fullservers[ handler ] = nil
                        handler.paused = false;
+                       out_put("server.lua: server [", ip, "]:", serverport, " resumed")
                end
        end
        handler.ip = function( )
@@ -235,6 +241,7 @@ wrapserver = function( listeners, socket, ip, serverport, pattern, sslctx ) -- t
        handler.readbuffer = function( )
                if _readlistlen >= _maxselectlen or _sendlistlen >= _maxselectlen then
                        handler.pause( )
+                       _fullservers[ handler ] = _currenttime
                        out_put( "server.lua: refused new client connection: server full" )
                        return false
                end
@@ -253,6 +260,8 @@ wrapserver = function( listeners, socket, ip, serverport, pattern, sslctx ) -- t
                        return;
                elseif err then -- maybe timeout or something else
                        out_put( "server.lua: error with new client connection: ", tostring(err) )
+                       handler.pause( )
+                       _fullservers[ handler ] = _currenttime
                        return false
                end
        end
@@ -265,6 +274,7 @@ wrapconnection = function( server, listeners, socket, ip, serverport, clientport
                out_error("server.lua: Disallowed FD number: "..socket:getfd()) -- PROTIP: Switch to libevent
                socket:close( ) -- Should we send some kind of error here?
                if server then
+                       _fullservers[ server ] = _currenttime
                        server.pause( )
                end
                return nil, nil, "fd-too-large"
@@ -398,6 +408,9 @@ wrapconnection = function( server, listeners, socket, ip, serverport, clientport
                out_put "server.lua: closed client handler and removed socket from list"
                return true
        end
+       handler.server = function ( )
+               return server
+       end
        handler.ip = function( )
                return ip
        end
@@ -803,6 +816,7 @@ getsettings = function( )
                max_connections = _maxselectlen;
                max_ssl_handshake_roundtrips = _maxsslhandshake;
                highest_allowed_fd = _maxfd;
+               accept_retry_interval = _accepretry;
        }
 end
 
@@ -818,6 +832,7 @@ changesettings = function( new )
        _tcpbacklog = tonumber( new.tcp_backlog ) or _tcpbacklog
        _sendtimeout = tonumber( new.send_timeout ) or _sendtimeout
        _readtimeout = tonumber( new.read_timeout ) or _readtimeout
+       _accepretry = tonumber( new.accept_retry_interval ) or _accepretry
        _maxselectlen = new.max_connections or _maxselectlen
        _maxsslhandshake = new.max_ssl_handshake_roundtrips or _maxsslhandshake
        _maxfd = new.highest_allowed_fd or _maxfd
@@ -849,7 +864,7 @@ loop = function(once) -- this is the main loop of the program
        local next_timer_time = math_huge;
        repeat
                local read, write, err = socket_select( _readlist, _sendlist, math_min(_selecttimeout, next_timer_time) )
-               for i, socket in ipairs( write ) do -- send data waiting in writequeues
+               for _, socket in ipairs( write ) do -- send data waiting in writequeues
                        local handler = _socketlist[ socket ]
                        if handler then
                                handler.sendbuffer( )
@@ -858,7 +873,7 @@ loop = function(once) -- this is the main loop of the program
                                out_put "server.lua: found no handler and closed socket (writelist)"    -- this should not happen
                        end
                end
-               for i, socket in ipairs( read ) do -- receive data
+               for _, socket in ipairs( read ) do -- receive data
                        local handler = _socketlist[ socket ]
                        if handler then
                                handler.readbuffer( )
@@ -875,17 +890,16 @@ loop = function(once) -- this is the main loop of the program
                _currenttime = luasocket_gettime( )
 
                -- Check for socket timeouts
-               local difftime = os_difftime( _currenttime - _starttime )
-               if difftime > _checkinterval then
+               if _currenttime - _starttime > _checkinterval then
                        _starttime = _currenttime
                        for handler, timestamp in pairs( _writetimes ) do
-                               if os_difftime( _currenttime - timestamp ) > _sendtimeout then
+                               if _currenttime - timestamp > _sendtimeout then
                                        handler.disconnect( )( handler, "send timeout" )
                                        handler:force_close()    -- forced disconnect
                                end
                        end
                        for handler, timestamp in pairs( _readtimes ) do
-                               if os_difftime( _currenttime - timestamp ) > _readtimeout then
+                               if _currenttime - timestamp > _readtimeout then
                                        if not(handler.onreadtimeout) or handler:onreadtimeout() ~= true then
                                                handler.disconnect( )( handler, "read timeout" )
                                                handler:close( )        -- forced disconnect?
@@ -908,6 +922,13 @@ loop = function(once) -- this is the main loop of the program
                        next_timer_time = next_timer_time - (_currenttime - _timer);
                end
 
+               for server, paused_time in pairs( _fullservers ) do
+                       if _currenttime - paused_time > _accepretry then
+                               _fullservers[ server ] = nil;
+                               server.resume();
+                       end
+               end
+
                -- wait some time (0 by default)
                socket_sleep( _sleeptime )
        until quitting;