[Samba] hangin when listing named pipes

[jra at dp.samba.org]

On Tue, Sep 03, 2002 at 09:47:54AM +0200, Kaj Mikkelsen wrote:
> Hi
> 
> Even when you are not opening the pipe, but just listing it in cygwin, or trying to see the properties in explorer, you will have this problem:
> Does anybody know how to disable named pipes in samba?
> Or how you can kill the connection from the client side?
> And no, setting    "nt pipe support" to no, doesn't fix the problem.
> /Kaj
> 
> 
> Symptom: 
> Samba daemon hanging when trying to open a named pipe.
> 
> Environment:
> Samba version 2.2.5
> RedHat 7.2
> Kernel 2.4.18 compiled with support for largefiles.
> Client is Win2000 sp 2
> 
> How to reproduce:
> 
> Unix side
> Go to your home directory (If it is exported by samba)
> make a named pipe: mkfifo .tst
> 
> Window side.
> Open your homedirectory in explorer.
> Click on .tst
> 
> 
> Diagnostics on the samba server:
> ps -ef | grep smbd | grep <yourname>
> strace -p <PID of your smbd process>
> 
> It should be hanging in an open statement
> open(".tst", O_RDONLY|O_LARGEFILE <unfinished ...>

The reason this happens now is that we used to open all
files with O_NONBLOCK, which would not block on a named
pipe open. We don't do that any more, but it is a simple
fix to make this happen for UNIX fifo's only.

Can you try this patch please :

Thanks,

	Jeremy.

Index: smbd/open.c
===================================================================
RCS file: /data/cvs/samba/source/smbd/open.c,v
retrieving revision 1.62.4.56
diff -u -r1.62.4.56 open.c
--- smbd/open.c 30 Aug 2002 19:30:02 -0000      1.62.4.56
+++ smbd/open.c 3 Sep 2002 19:31:23 -0000
@@ -158,6 +158,16 @@

                local_flags &= ~O_TRUNC;

+#if defined(O_NONBLOCK) && defined(S_ISFIFO)
+               /*
+                * We would block on opening a FIFO with no one else on the
+                * other end. Do what we used to do and add O_NONBLOCK to the
+                * open flags. JRA.
+                */
+
+               if (VALID_STAT(*psbuf) && S_ISFIFO(psbuf->st_mode))
+                       local_flags |= O_NONBLOCK;
+#endif
                fsp->fd = fd_open(conn, fname, local_flags, mode);

                if (fsp->fd == -1)  {