Forward server works for multiple tunnels.

Http.lua has been patched to support non-blocking everything.
Makefile for linux has been updated with new names.

samples/forward.lua

@@ -1,11 +1,5 @@
 -- load our favourite library
 local socket = require"socket"
--- timeout before an inactive thread is kicked
-local TIMEOUT = 10
--- local address to bind to
-local ihost, iport = arg[1] or "localhost", arg[2] or 8080
--- address to forward all data to
-local ohost, oport = arg[3] or "localhost", arg[4] or 3128
 
 -- creates a new set data structure
 function newset()
@@ -32,12 +26,44 @@ function newset()
     }})
 end
 
+-- timeout before an inactive thread is kicked
+local TIMEOUT = 10
+-- set of connections waiting to receive data
 local receiving = newset()
+-- set of sockets waiting to send data
 local sending = newset() 
+-- context for connections and servers
 local context = {}
 
--- starts a non-blocking connect
-function nconnect(host, port)
+-- initializes the forward server
+function init()
+    if table.getn(arg) < 1 then
+        print("Usage")
+        print("    lua forward.lua <iport:ohost:oport> ...")
+        os.exit(1)
+    end
+    -- for each tunnel, start a new server socket
+    for i, v in ipairs(arg) do
+        -- capture forwarding parameters
+        local iport, ohost, oport = 
+            socket.skip(2, string.find(v, "([^:]+):([^:]+):([^:]+)"))
+        assert(iport, "invalid arguments")
+        -- create our server socket
+        local server = assert(socket.bind("*", iport))
+        server:settimeout(0.1) -- we don't want to be killed by bad luck
+        -- make sure server is tested for readability
+        receiving:insert(server)
+        -- add server context
+        context[server] = { 
+            thread = coroutine.create(accept),
+            ohost = ohost,
+            oport = oport
+        }
+    end
+end
+
+-- starts a connection in a non-blocking way
+function nbkcon(host, port)
     local peer, err = socket.tcp()
     if not peer then return nil, err end
     peer:settimeout(0)
@@ -52,7 +78,6 @@ end
 
 -- gets rid of a client
 function kick(who)
-if who == server then error("FUDEU") end
     if context[who] then
         sending:remove(who)
         receiving:remove(who)
@@ -63,7 +88,6 @@ end
 
 -- decides what to do with a thread based on coroutine return
 function route(who, status, what)
-print(who, status, what)
     if status and what then
         if what == "receiving" then receiving:insert(who) end
         if what == "sending" then sending:insert(who) end
@@ -73,12 +97,13 @@ end
 -- loops accepting connections and creating new threads to deal with them
 function accept(server)
     while true do
-print(server, "accepting a new client")
         -- accept a new connection and start a new coroutine to deal with it
         local client = server:accept()
         if client then
             -- start a new connection, non-blockingly, to the forwarding address
-            local peer = nconnect(ohost, oport)
+            local ohost = context[server].ohost
+            local oport = context[server].oport
+            local peer = nbkcon(ohost, oport)
             if peer then
                 context[client] = {
                     last = socket.gettime(),
@@ -90,7 +115,7 @@ print(server, "accepting a new client")
                 sending:insert(peer)
                 context[peer] = {
                     peer = client,
-                    thread = coroutine.create(check),
+                    thread = coroutine.create(chkcon),
                     last = socket.gettime()
                 }
                 -- put both in non-blocking mode
@@ -109,14 +134,12 @@ end
 -- forwards all data arriving to the appropriate peer
 function forward(who)
     while true do
-print(who, "getting data")
         -- try to read as much as possible
         local data, rec_err, partial = who:receive("*a")
         -- if we had an error other than timeout, abort
         if rec_err and rec_err ~= "timeout" then return error(rec_err) end
         -- if we got a timeout, we probably have partial results to send
         data = data or partial
-print(who, " got ", string.len(data))
         -- renew our timestamp so scheduler sees we are active
         context[who].last = socket.gettime()
         -- forward what we got right away
@@ -126,7 +149,6 @@ print(who, " got ", string.len(data))
             coroutine.yield("sending")
             local ret, snd_err
             local start = 0
-print(who, "sending data")
             ret, snd_err, start = peer:send(data, start+1)
             if ret then break 
             elseif snd_err ~= "timeout" then return error(snd_err) end
@@ -143,51 +165,22 @@ end
 
 -- checks if a connection completed successfully and if it did, starts
 -- forwarding all data
-function check(who)
+function chkcon(who)
     local ret, err = who:connected()
     if ret then 
-print(who, "connection completed")
         receiving:insert(context[who].peer)
         context[who].last = socket.gettime()
-print(who, "yielding until there is input data")
         coroutine.yield("receiving")
         return forward(who)
     else return error(err) end
 end
 
--- initializes the forward server
-function init()
-    -- socket sets to test for events 
-    -- create our server socket
-    server = assert(socket.bind(ihost, iport))
-    server:settimeout(0.1) -- we don't want to be killed by bad luck
-    -- we initially
-    receiving:insert(server)
-    context[server] = { thread = coroutine.create(accept) }
-end
-
 -- loop waiting until something happens, restarting the thread to deal with
 -- what happened, and routing it to wait until something else happens
 function go()
     while true  do
-print("will select for readability")
-for i,v in ipairs(receiving) do
-    print(i, v)
-end
-print("will select for writability")
-for i,v in ipairs(sending) do
-    print(i, v)
-end
         -- check which sockets are interesting and act on them
         readable, writable = socket.select(receiving, sending, 3)
-print("returned as readable")
-for i,v in ipairs(readable) do
-    print(i, v)
-end
-print("returned as writable")
-for i,v in ipairs(writable) do
-    print(i, v)
-end
         -- for all readable connections, resume its thread and route it 
         for _, who in ipairs(readable) do
             receiving:remove(who)
@@ -207,7 +200,6 @@ end
         local deathrow
         for who, data in pairs(context) do
             if data.last then
-print("hung for" , now - data.last, who)
                 if  now - data.last > TIMEOUT then
                     -- only create table if someone is doomed
                     deathrow = deathrow or {} 
@@ -217,13 +209,10 @@ print("hung for" , now - data.last, who)
         end
         -- finally kick everyone in deathrow
         if deathrow then
-print("in death row")
-for i,v in pairs(deathrow) do
-    print(i, v)
-end
             for who in pairs(deathrow) do kick(who) end
         end
     end
 end
 
-go(init())
+init()
+go()