X-Git-Url: http://git.onelab.eu/?p=vsys.git;a=blobdiff_plain;f=fifowatcher.ml;h=58113a138ce3ec35e2eab0f81ba551f12cc042bc;hp=6e2a12aaf5b4504bb04ae64383c38d40642c1322;hb=HEAD;hpb=60f2512c4e00781655fae17a005ebe9452951abe diff --git a/fifowatcher.ml b/fifowatcher.ml index 6e2a12a..58113a1 100644 --- a/fifowatcher.ml +++ b/fifowatcher.ml @@ -5,21 +5,23 @@ open Unix open Globals open Dirwatcher open Printf +open Splice (** A connected process, FIFO *) -type channel_pipe = Process of out_channel | Fifo of out_channel | BrokenPipe -(** Signed file descriptors. Usually, we'll make sure that they're not - mistreated *) +type channel_pipe = Process of Unix.file_descr | Fifo of Unix.file_descr | BrokenPipe + +(** Signed file descriptors. *) type signed_fd = Infd of Unix.file_descr | Outfd of Unix.file_descr | Eventfd of Unix.file_descr +(** XXX This will get deprecated when we switch to inotify *) let fdmap: (Unix.file_descr,string*string) Hashtbl.t = Hashtbl.create 1024 + (** Maps pids to slice connections. Needed to clean up fds when a script dies with EPIPE *) let pidmap: (int,signed_fd list) Hashtbl.t = Hashtbl.create 1024 let backend_prefix = ref "" let open_fds: (Unix.file_descr,channel_pipe) Hashtbl.t = Hashtbl.create 1024 - (** Receive an event from a running script. This event must be relayed to the slice that invoked it. @@ -29,31 +31,31 @@ let receive_process_event (idesc: fname_and_fd) (_: fname_and_fd) = let (_,ifd) = idesc in let cp = try Hashtbl.find open_fds ifd with Not_found-> - fprintf logfd "Fifo fd disappeared\n";flush logfd;raise Bug + logprint "Fifo fd disappeared\n";raise Bug in match (cp) with - | Fifo(fifo_outchan) -> - let process_inchan = in_channel_of_descr ifd in - let cont = ref true in - while (!cont) do - try - let curline = input_line process_inchan in - fprintf fifo_outchan "%s\n" curline;flush fifo_outchan - with - | End_of_file|Sys_blocked_io|Unix_error(EPIPE,_,_)|Unix_error(EBADF,_,_) -> - begin - cont:=false - end - | Unix_error(_,s1,s2) -> fprintf logfd "Unix error %s - %s\n" s1 s2;flush logfd;cont:=false - | Sys_error(s) -> (* We get this error if the EPIPE comes before the EOF marker*) cont:=false - | e -> fprintf logfd "Error - received unexpected event from file system !!!\n";raise e - done - | _ -> fprintf logfd "Bug! Process fd received in the channel handler\n";flush logfd;raise Bug + | Fifo(fifo_outfd) -> + begin + try + printf "Received process event\n";flush Pervasives.stdout; + (* transferred = 4096 => there were at least 4096 bytes in the + * stream, so we should try again. + * transferred < 4096 => EAGAIN => either this is all the data we + * have (move on) + * OR XXX the receiver is blocking (supposedly this can't happen) *) + let transferred = ref 4096 in + while (!transferred == 4096) do + transferred:=tee ifd fifo_outfd 4096 + done; + with + Failure(s)->logprint "Transfer failure: %s\n" s + end + | _ -> logprint "Bug! Process fd received in the channel handler\n";raise Bug let rec openentry_int fifoin fifoout (abspath:string*string) = 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 Hashtbl.replace fdmap fdin abspath; Fdwatcher.add_fd (Some(fifoin),fdin) (Some(fifoout),stdout) receive_fifo_event @@ -61,16 +63,16 @@ and reopenentry_int fdin fifoin fifoout = close fdin; Fdwatcher.del_fd fdin; let abspath = try - Hashtbl.find fdmap fdin with _ -> fprintf logfd "Bug: Phantom pipe\n";flush logfd;raise Bug + Hashtbl.find fdmap fdin with _ -> logprint "Bug: Phantom pipe\n";raise Bug in openentry_int fifoin fifoout abspath + (** receive an event from a fifo and connect to the corresponding service, or to create it if it doesn't exit @param eventdescriptor Name of input pipe,in descriptor @param outdescriptor Name of output pipe, out descriptor *) and receive_fifo_event eventdescriptor outdescriptor = - printf "received fifo event\n";flush Pervasives.stdout; let (evfname,evfd) = eventdescriptor in let (fname_other,fd_other) = outdescriptor in (* Open the output pipe, or use stdout instead *) @@ -79,22 +81,21 @@ and receive_fifo_event eventdescriptor outdescriptor = | Some(str)-> ( try openfile str [O_WRONLY;O_NONBLOCK] 0o777 with - _->fprintf logfd "Output pipe not open, using stdout in place of %s\n" str;flush logfd;stdout + _->logprint "Output pipe not open, using stdout in place of %s\n" str;stdout ) - | None-> fprintf logfd "Bug, nameless pipe\n";flush logfd;raise Bug + | None-> logprint "Bug, nameless pipe\n";raise Bug in (* Check if the input descriptor is already registered (=> a session is open). If not, register it and start a new session.*) let pipe = try Hashtbl.find open_fds evfd with | Not_found -> - printf "fd not found!\n";flush Pervasives.stdout; (* Ok, need to launch script *) let execpath,slice_name = Hashtbl.find fdmap evfd in let (script_infd,pout) = Unix.pipe () in let (pin,script_outfd) = Unix.pipe () in set_nonblock script_infd; ignore(sigprocmask SIG_BLOCK [Sys.sigchld]); - let rpid = try Some(create_process execpath [|execpath;slice_name|] pin pout pout) with e -> fprintf logfd "Error executing service: %s\n" execpath;flush logfd;None + let rpid = try Some(create_process execpath [|execpath;slice_name|] pin pout pout) with e -> logprint "Error executing service: %s\n" execpath;None in match rpid with | None-> BrokenPipe @@ -104,55 +105,44 @@ and receive_fifo_event eventdescriptor outdescriptor = Hashtbl.add pidmap pid [Infd(script_infd);Outfd(script_outfd);Eventfd(evfd)]; (* Connect pipe to running script *) - Hashtbl.add open_fds evfd (Process(out_channel_of_descr script_outfd)); + Hashtbl.add open_fds evfd (Process(script_outfd)); (* Connect the running script to the pipe *) - Hashtbl.add open_fds script_infd (Fifo(out_channel_of_descr outfd)); + Hashtbl.add open_fds script_infd (Fifo(outfd)); (* Activate running script *) Fdwatcher.add_fd (None,script_infd) (None,script_infd) receive_process_event; - (Process(out_channel_of_descr script_outfd)) + (Process(script_outfd)) in - (* We have the connection to the process - because it was open, or because it - just got established *) - let inchan_fd = in_channel_of_descr evfd in + (* We have the connection to the process - because it was open, or because it + just got established *) match (pipe) with - | Process(out_channel) -> - let cont = ref true in - while (!cont) do - try - fprintf logfd "Reading...\n";flush logfd; - let curline = input_line inchan_fd in - fprintf out_channel "%s\n" curline;flush out_channel - with - |End_of_file-> - ( - match (evfname,fname_other) with - | Some(str1),Some(str2)-> - fprintf logfd "Reopening entry\n";flush logfd; - reopenentry_int evfd str1 str2 - | Some(str1),None -> - fprintf logfd "Bug, nameless pipe\n";flush logfd;raise Bug - | None,_ -> - fprintf logfd "Race condition -> user deleted file before closing it. Clever ploy, but won't work.\n"; - flush logfd - ); - cont:=false - |Sys_blocked_io ->fprintf logfd "Sysblockedio\n";flush logfd; - cont:=false - | Unix_error(_,s1,s2) -> fprintf logfd "Unix error %s - %s\n" s1 s2;flush logfd;cont:=false - (*| _ ->fprintf logfd "Bug: unhandled exception\n";flush - * logfd;raise Bug*) - done; - ignore(sigprocmask SIG_UNBLOCK [Sys.sigchld]) + | Process(fifo_outfd) -> + begin + try + let transferred = ref 4096 in + while (!transferred == 4096) do + begin + transferred:=tee evfd fifo_outfd 4096; + printf "Transferred: %d\n" !transferred;flush Pervasives.stdout + end + done; + with Failure(str) -> + begin + logprint "Error connecting user to service: %s\n" str + end; + ignore(sigprocmask SIG_UNBLOCK [Sys.sigchld]); + printf "Out of the loop\n";flush Pervasives.stdout + + end | BrokenPipe -> () - | Fifo(_) -> fprintf logfd "BUG! received process event from fifo\n";raise Bug + | Fifo(_) -> logprint "BUG! received process event from fifo\n";raise Bug (** 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 _ -> ()); @@ -163,14 +153,14 @@ let mkentry fqp abspath perm uname = Unix.mkfifo infname 0o666; Unix.mkfifo outfname 0o666; ( (* Make the user the owner of the pipes in a non-chroot environment *) - if (!Globals.nochroot) then - let pwentry = Unix.getpwnam uname in - Unix.chown infname pwentry.pw_uid pwentry.pw_gid; - Unix.chown outfname pwentry.pw_uid pwentry.pw_gid + if (!Globals.nochroot) then + let pwentry = Unix.getpwnam uname in + Unix.chown infname pwentry.pw_uid pwentry.pw_gid; + Unix.chown outfname pwentry.pw_uid pwentry.pw_gid ); 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) (** Open fifos for a session. Will shutdown vsys if the fifos don't exist *) let openentry fqp abspath perm =