added simple udp echo server using luasocket

2 files changed, 41 insertions, 2 deletions

diff --git a/src/anylike.c b/src/anylike.c
index 1fd8442..91088b8 100644
--- a/src/anylike.c
+++ b/src/anylike.c
@@ -82,6 +82,7 @@ static const luaL_Reg anylike_lualibs[] = {
   {LUA_LOADLIBNAME, luaopen_package},
   {LUA_TABLIBNAME, luaopen_table},
   {LUA_STRLIBNAME, luaopen_string},
+  {LUA_MATHLIBNAME, luaopen_math},
   {LUA_LOGLIBNAME, luaopen_log},
   {LUA_CRYPTLIBNAME, luaopen_crypt},
   {NULL, NULL}
diff --git a/src/main_loop.lua b/src/main_loop.lua
index 785f7b2..5de973a 100644
--- a/src/main_loop.lua
+++ b/src/main_loop.lua
@@ -23,10 +23,48 @@
 --  along with anylike. If not, see <http://www.gnu.org/licenses/>.
 --
 
+socket = require("socket")
+
 function main_loop(opt) 
    log.print("NOTICE", "main_loop started")
-
-   -- add main loop
    
+   local host, port = "localhost", 4500
+   local ip, err = socket.dns.toip(host)
+   if(ip == nil) then
+      log.print("ERROR", "can't resolve " .. host .. ": " .. err)
+      return -1
+   end
+
+   local udp, err = socket.udp()
+   if(udp == nil) then
+      log.print("ERROR", "can't create udp socket")
+      return -1
+   end
+      
+   local ret, err = udp:setsockname(ip, port)
+   if(ret == nil) then
+      log.print("ERROR", "sendto(" .. ip .. "," .. port .. " failed: " .. err)
+      return -1
+   end
+             
+   while true do
+      local dgrm, from_ip, from_port = udp:receivefrom()
+      if(ret == nil) then
+         log.print("ERROR", "receivefrom(" .. ip .. "," .. port .. " failed: " .. from_ip)
+         return -1
+      end
+      
+      local ret, err = udp:sendto(dgrm, from_ip, from_port)
+      if(ret == nil) then
+         log.print("ERROR", "sendto(" .. ip .. "," .. port .. " failed: " .. err)
+         return -1
+      end
+      
+      if(string.gsub(dgrm, "^(%w+)%s*%c$", "%1") ==  "quit") then
+         return 0
+      end
+
+   end
+
    return 0 -- =0 -> OK, <0 -> error, >0 -> signal
 end