+type in_pathname = string
+type directory = string
+type base_pathname = string
+type slice_name = string
+
+let direct_fifo_table: (in_pathname,(directory*base_pathname*slice_name*Unix.file_descr) option) Hashtbl.t =
+ Hashtbl.create 1024
+
+let pidmap: (int,in_pathname * Unix.file_descr) Hashtbl.t = Hashtbl.create 1024
+
+let move_gate fname =
+ let tmpfname=String.concat "." [fname;"tmp"] in
+ (* XXX add a check *)
+ Unix.rename fname tmpfname;
+ tmpfname
+
+let move_ungate fname restore =
+ (* XXX add a check *)
+ Unix.rename restore fname
+
+let list_check lst elt _ =
+ let rec list_check_rec lst =
+ match lst with
+ | [] -> false
+ | car::cdr ->
+ if (car==elt) then
+ true
+ else
+ list_check_rec cdr
+ in
+ list_check_rec lst
+
+let fs_openentry fifoin =
+ let fdin =
+ try openfile fifoin [O_RDONLY;O_NONBLOCK] 0o777 with
+ e->logprint "Error opening and connecting FIFO: %s,%o\n" fifoin 0o777;raise e
+ in
+ fdin
+
+(** Open entry safely, by first masking out the file to be opened *)
+let openentry_safe root_dir fqp_in backend_spec =
+ let restore = move_gate fqp_in in
+ let fd_in = fs_openentry restore in
+ move_ungate fqp_in restore;
+ let (fqp,slice_name) = backend_spec in
+ Hashtbl.replace direct_fifo_table fqp_in (Some(root_dir,fqp,slice_name,fd_in))
+
+let openentry root_dir fqp backend_spec =
+ let fqp_in = String.concat "." [fqp;"in"] in
+ openentry_safe root_dir fqp_in backend_spec
+
+let reopenentry fifoin =
+ let entry = try Hashtbl.find direct_fifo_table fifoin with _ -> None in
+ match entry with
+ | Some(dir, fqp,slice_name,fd) -> close_if_open fd;openentry_safe dir fifoin (fqp,slice_name)
+ | None -> ()