X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=directfifowatcher.ml;h=e97d7c5e33c4822bf23b2a6ecc5148084a2a994e;hb=26326ab885a36f7e0661703b735109df36520b30;hp=397229275b913adb6882bbf8080c12356e60c43c;hpb=46e48c60e9d524bf71631561e193c443613a2bb5;p=vsys.git diff --git a/directfifowatcher.ml b/directfifowatcher.ml index 3972292..e97d7c5 100644 --- a/directfifowatcher.ml +++ b/directfifowatcher.ml @@ -21,39 +21,59 @@ open Splice let close_if_open fd = (try (ignore(close fd);) with _ -> ()) - -let direct_fifo_table: (string,(string*string*string*Unix.file_descr) option) Hashtbl.t = Hashtbl.create 1024 -let pidmap: (int,string) Hashtbl.t = Hashtbl.create 1024 - -let rec list_check lst elt = - match lst with - | [] -> false - | car::cdr -> if (car==elt) then true else list_check cdr elt +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 + Unix.rename fname tmpfname; + tmpfname + +let move_ungate fname restore = + 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 openentry_int fifoin = let fdin = try openfile fifoin [O_RDONLY;O_NONBLOCK] 0o777 with - e->fprintf logfd "Error opening and connecting FIFO: %s,%o\n" fifoin 0o777;flush logfd;raise e + e->logprint "Error opening and connecting FIFO: %s,%o\n" fifoin 0o777;raise e in fdin - -(** Open fifos for a session. SHOULD NOt shutdown vsys if the fifos don't exist *) -let openentry_in root_dir fqp_in backend_spec = - Dirwatcher.mask_watch root_dir; - let fd_in = openentry_int fqp_in in - Dirwatcher.unmask_watch root_dir [S_Open]; - let (fqp,slice_name) = backend_spec in - Hashtbl.replace direct_fifo_table fqp_in (Some(root_dir,fqp,slice_name,fd_in)) +(** 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 = openentry_int 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_in root_dir fqp_in backend_spec + 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_in dir fifoin (fqp,slice_name) + | Some(dir, fqp,slice_name,fd) -> close_if_open fd;openentry_safe dir fifoin (fqp,slice_name) | None -> () (* vsys is activated when a client opens an in file *) @@ -63,32 +83,35 @@ let connect_file fqp_in = Hashtbl.find direct_fifo_table fqp_in with _ -> None in match entry_info with | Some(_,execpath,slice_name,fifo_fdin) -> - fprintf logfd "Executing %s for slice %s\n" execpath slice_name;flush logfd; begin let len = String.length fqp_in in let fqp = String.sub fqp_in 0 (len-3) in let fqp_out = String.concat "." [fqp;"out"] in let fifo_fdout = try openfile fqp_out [O_WRONLY;O_NONBLOCK] 0o777 with - _->fprintf logfd "%s Output pipe not open, using stdout in place of %s\n" slice_name fqp_out;flush logfd;stdout + _-> (* The client is opening the descriptor too fast *) + sleep 1;try openfile fqp_out [O_WRONLY;O_NONBLOCK] 0o777 with + _-> + logprint "%s Output pipe not open, using stdout in place of %s\n" slice_name fqp_out;stdout in - ignore(sigprocmask SIG_BLOCK [Sys.sigchld]); - ( - clear_nonblock fifo_fdin; - let pid=try Some(create_process execpath [|execpath;slice_name|] fifo_fdin fifo_fdout fifo_fdout) with e -> None in - if (fifo_fdout <> stdout) then close_if_open fifo_fdout; - match pid with - | Some(pid) ->Hashtbl.add pidmap pid fqp_in - | None ->fprintf logfd "Error executing service: %s\n" execpath;flush logfd;reopenentry fqp_in - ); - ignore(sigprocmask SIG_UNBLOCK [Sys.sigchld]); + ignore(sigprocmask SIG_BLOCK [Sys.sigchld]); + ( + clear_nonblock fifo_fdin; + let pid=try Some(create_process execpath [|execpath;slice_name|] fifo_fdin fifo_fdout fifo_fdout) with e -> None in + match pid with + | Some(pid) -> + if (fifo_fdout <> stdout) then close_if_open fifo_fdout; + Hashtbl.add pidmap pid (fqp_in,fifo_fdout) + | None ->logprint "Error executing service: %s\n" execpath;reopenentry fqp_in + ); + ignore(sigprocmask SIG_UNBLOCK [Sys.sigchld]); end | None -> () (** Make a pair of fifo entries *) let mkentry fqp abspath perm uname = - fprintf logfd "Making entry %s->%s\n" fqp abspath;flush logfd; + logprint "Making entry %s->%s\n" fqp abspath; let fifoin=sprintf "%s.in" fqp in let fifoout=sprintf "%s.out" fqp in (try Unix.unlink fifoin with _ -> ()); @@ -106,7 +129,7 @@ let mkentry fqp abspath perm uname = ); Success with - e->fprintf logfd "Error creating FIFO: %s->%s. May be something wrong at the frontend.\n" fqp fifoout;flush logfd;Failed) + e->logprint "Error creating FIFO: %s->%s. May be something wrong at the frontend.\n" fqp fifoout;Failed) (** Close fifos that just got removed *) @@ -122,25 +145,23 @@ let closeentry fqp = let sigchld_handle s = let pid,_=Unix.waitpid [Unix.WNOHANG] 0 in try - let fqp_in = Hashtbl.find pidmap pid in - reopenentry fqp_in + let fqp_in,fd_out = Hashtbl.find pidmap pid in + begin + reopenentry fqp_in + end with _ -> () let rec add_dir_watch fqp = Dirwatcher.add_watch fqp [S_Open] direct_fifo_handler and -direct_fifo_handler wd dirname evlist fname = + direct_fifo_handler wd dirname evlist fname = let is_event = list_check evlist in - if (is_event Open) then + if (is_event Open Attrib) then let fqp_in = String.concat "/" [dirname;fname] in - begin - connect_file fqp_in; - add_dir_watch dirname - end + connect_file fqp_in let del_dir_watch fqp = - (* XXX Dirwatcher.del_watch fqp *) () let initialize () = - Sys.set_signal Sys.sigchld (Sys.Signal_handle sigchld_handle) + Sys.set_signal Sys.sigchld (Sys.Signal_handle sigchld_handle)