replaced fserv.lua with a much cleaner version that uses libsyslog

FRequest/OpenOS/etc/rc.d/fserv.lua

@@ -1,83 +1,129 @@
 local net = require "net"
-local fs = require "filesystem"
 local event = require "event"
+local syslog = require "syslog"
+local fs = require "filesystem"
+local computer = require "computer"
+local serial = require "serialization"
 
-local prefix = "/srv"
-local process = nil
-local listener = nil
-local dbug = false
+local sockets = {}
+local cfg = {}
+cfg.path = "/srv"
+cfg.looptime = 0.5
+local timer = false
 
-local function dprint(...)
- if dbug then
-  print(...)
+local function log(msg,level)
+ syslog(msg,level,"frequestd")
+end
+
+local function loadConfig()
+ local fobj = io.open("/etc/fserv.cfg","rb")
+ if fobj then
+  config = serial.unserialize(fobj:read("*a")) or config
+  fobj:close()
  end
 end
 
+local function writeConfig()
+ local fobj = io.open("/etc/fserv.cfg","wb")
+ if fobj then
+  fobj:write(serial.serialize(config))
+  fobj:close()
+ end
+end
+
+--[[
+overview of how this works:
+socketHandler listens for connections on port 70, places them into the sockets table
+socketLoop runs quite regularly - every cfg.looptime or so.
+It iterates over each socket in the sockets table, and if any of them contain a valid request, it attempts to handle it:
+- calls getFile to get a status code and file contents if applicable
+- writes either a failure code and message, the file contents, or the file size
+Previously this was based on a listener but that caused a race condition
+
+note to self: consider using the FS library for handling stat requests, and returning an iterator instead of an entire file for transfer requests
+]]--
+
+local function getFile(path)
+ path = cfg.path .. path
+ if not fs.exists(path) then
+  log(path.." not found",syslog.notice)
+  return "n",path.." not found"
+ end
+ if fs.isDirectory(path) then
+  local dlist = ""
+  for file in fs.list(path) do
+   dlist = dlist .. file .. "\n"
+  end
+  return "d", dlist
+ end
+ local f = io.open(path,"rb")
+ if not f then
+  log("unable to open "..path,syslog.notice)
+  return "f","unable to open "..path
+ end
+ local content = f:read("*a")
+ f:close()
+ return "y", content
+end
+
+local function socketLoop()
+ for sn,socket in pairs(sockets) do
+  local op, path = socket.rbuffer:match("([ts])(.+)\n")
+  if op and path then
+   path = fs.canonical(path)
+   if path:sub(1,1) ~= "/" then
+    path = "/" .. path
+   end
+   log("client "..tostring(socket.addr)..":"..tostring(socket.port).." requested "..path, syslog.debug)
+   if op == "t" and path then
+    local wf, file = getFile(path)
+    socket:write(wf .. file)
+    socket:close()
+    sockets[sn] = nil
+   elseif op == "s" and path then
+    local wf, file = getFile(path)
+    if wf == "y" then
+     socket:write(wf..file:len())
+    else
+     socket:write(wf..file)
+    end
+    socket:close()
+    sockets[sn] = nil
+   end
+  end
+  if computer.uptime() > socket.opened + 60 then
+   socket:close()
+   sockets[sn] = nil
+   log("dropped client "..tostring(socket.addr)..":"..tostring(socket.port).." for inactivity",syslog.debug)
+  elseif socket.state ~= "open" then
+   sockets[sn] = nil
+   log("client "..tostring(socket.addr)..":"..tostring(socket.port).." closed socket",syslog.debug)
+  end
+ end
+end
+
+local function socketHandler(socket)
+ log(tostring(socket.addr)..":"..tostring(socket.port).." opened",syslog.debug)
+ socket.opened = computer.uptime()
+ sockets[tostring(socket.addr)..":"..tostring(socket.port)] = socket
+end
+
 function start()
- process = net.flisten(70,function(s)
- local buffer = ""
- local function lf()
-  buffer=s:read(1024)
-  local nl = buffer:find("\n")
-  if nl then
-   local rt = buffer:sub(1,1)
-   local path=prefix .. "/" .. buffer:sub(2,nl-1)
-   dprint(path)
-   if path:find("%.%./") then
-    s:write("f to pay respects")
-    s:close()
-    return
-   end
-   if fs.exists(path) then
-    if rt == "t" then
-     if fs.isDirectory(path) then 
-      s:write("d")
-      if fs.exists(path.."/index") then
-       local f=io.open(path.."/index","rb")
-       s:write(f:read("*a"))
-       f:close()
-      end
-      local dbuffer = ""
-      for f in fs.list(path) do
-       dbuffer = dbuffer..f.."\n"
-       dprint(f)
-      end
-      s:write(dbuffer)
-      s:close()
-     else
-      s:write("y")
-      local f = io.open(path,"rb")
-      s:write(f:read("*a"))
-      f:close()
-      s:close()
-     end
-    else
-     s:write(tostring(fs.size(path)))
-     s:close()
-    end
-   else
-    dprint("404")
-    s:write("not found")
-    s:close()
-   end
-  end
- end
- listener = lf
- event.listen("net_msg",lf)
- end)
+ loadConfig()
+ writeConfig()
+ net.flisten(70, socketHandler)
+ timer = event.timer(cfg.looptime, socketLoop, math.huge)
 end
 
 function stop()
- event.ignore("net_msg",listener)
- event.ignore("net_msg",process)
+ event.ignore("net_msg", socketLoop)
+ event.cancel(timer)
 end
 
-function debug()
- dbug = not dbug
-end
-function set_path(newpath)
- if fs.exists(newpath) then
-  prefix=newpath
-  print("prefix = "..newpath)
+function set(k,v)
+ if cfg[k] then
+  cfg[k] = v
+  print("cfg."..k.." = "..v)
  end
+ writeConfig()
 end

programs.cfg

@@ -15,10 +15,11 @@
    ["master/FRequest/OpenOS/etc/rc.d/fserv.lua"] = "//etc/rc.d"
   },
   dependencies = {
-   ["minitel"] = ""
+   ["minitel"] = "",
+   ["libsyslog"] = ""
   },
   name = "FRequest Daemon",
-  description = "Dumb-as-rocks FRequest server",
+  description = "Reasonably sane FRequest server",
   authors = "Izaya",
   repo = "tree/master/"
  },