Use Arg to parse arguments

bin/main.ml

@@ -1,11 +1,24 @@
+let usage_msg = "inspector -log <logfile> -db <dbfile>"
+let logfile = ref ""
+let dbfile = ref ""
+
+let speclist =
+  [
+    ("-log", Arg.Set_string logfile, "Set log filename");
+    ("-db", Arg.Set_string dbfile, "Set XAPI db file");
+  ]
+
+let ignore_anon arg = print_endline @@ arg ^ " is ignored"
+
 let () =
-  let open Inspector in
-  if Array.length Sys.argv <> 2 then (
-    Printf.eprintf "Usage: %s <logfile>\n" (Filename.basename Sys.argv.(0));
+  Arg.parse speclist ignore_anon usage_msg;
+  if !logfile = "" then (
+    Printf.eprintf "You must specify a log file using -log\n";
     exit 1);
 
-  let s = State.create Sys.argv.(1) in
+  let open Inspector in
+  let s = State.create !logfile in
+  Printf.printf "dbfile is currently ignored\n";
   Printf.printf "Loaded %d lines\n" (State.size s);
   Repl.help ();
-
   Repl.loop s