fix(lua): Make rtorrent.lua accessible at start

lua/rtorrent.lua

@@ -0,0 +1,42 @@
+-- the "rtorrent" table is passed in by the C++ code, modify and
+-- return it for loading.
+local args = {...}
+local rtorrent = args[1]
+
+-- Autocall
+-- Allows syntax like `rtorrent.autocall.system.hostname()`
+local mt = {}
+function mt.__call (t, ...)
+   name = table.concat(rawget(t, "__namestack"), ".")
+   success, ret = pcall(rtorrent.call, name, ...)
+   if not success then error(name..": "..ret, 2) end
+   return ret
+end
+function mt.__index (t, key)
+   ns = rawget(t, "__namestack") or {}
+   table.insert(ns, key)
+   return setmetatable({__namestack=ns}, mt)
+end
+rtorrent["autocall"] = setmetatable({}, mt)
+
+-- Autocall-config Same as autocall, but passes an empty first target
+-- implicitly, for syntax like `rtorrent.autocall_config.session.directory.set("/tmp/")`
+local mt = {}
+function mt.__call (t, ...)
+   name = table.concat(rawget(t, "__namestack"), ".")
+   success, ret = pcall(rtorrent.call, name, "", ...)
+   if not success then error(name..": "..ret, 2) end
+   return ret
+end
+function mt.__index (t, key)
+   ns = rawget(t, "__namestack")
+   if ns == nil then
+      if _G[key] ~= nil then return _G[key] end
+      ns = {}
+   end
+   table.insert(ns, key)
+   return setmetatable({__namestack=ns}, mt)
+end
+rtorrent["autocall_config"] = setmetatable({}, mt)
+
+return rtorrent