kern/94772: FIFOs (named pipes) + select() == broken

[Oliver Fromme]

The following reply was made to PR kern/94772; it has been noted by GNATS.

From: Oliver Fromme <olli at lurza.secnetix.de>
To: bde at zeta.org.au (Bruce Evans)
Cc: bug-followup at freebsd.org
Subject: Re: kern/94772: FIFOs (named pipes) + select() == broken
Date: Fri, 24 Mar 2006 21:49:29 +0100 (CET)

 Oliver Fromme wrote:
  > Oh, by the way, the patch set that I mailed still has
  > two failure cases with nameless pipes (I didn't notice
  > at first because I only tested the NAMEDPIPE case):
  > 
  > not ok 4  Pipe state 6a: expected POLLHUP; got POLLIN | POLLHUP
  > not ok 8  Pipe state 6a: expected POLLHUP; got POLLIN | POLLHUP
  > 
  > Those were broken before, too, so my patch doesn't make
  > things worse, at least.  :-)   I'll try to fix those,
  > too.
 
 Those were easy to fix.  It's basically a patch that just
 removes one line in kern/sys_pipe.c:pipe_poll().  This
 patch is independent from the others and can be applied
 separately.  I've added it to the patchset on my website:
 http://www.secnetix.de/~olli/tmp/fifodiff.txt
 
 Now _all_ current checks from the test programs are
 successful, both select() and poll(), and both for FIFOs
 and for nameless pipes.
 
 Best regards
    Oliver
 
 --- src/sys/kern/sys_pipe.c.orig	Tue Jan 31 16:44:51 2006
 +++ src/sys/kern/sys_pipe.c	Fri Mar 24 19:23:03 2006
 @@ -1350,8 +1350,7 @@
  #endif
  	if (events & (POLLIN | POLLRDNORM))
  		if ((rpipe->pipe_state & PIPE_DIRECTW) ||
 -		    (rpipe->pipe_buffer.cnt > 0) ||
 -		    (rpipe->pipe_state & PIPE_EOF))
 +		    (rpipe->pipe_buffer.cnt > 0))
  			revents |= events & (POLLIN | POLLRDNORM);
  
  	if (events & (POLLOUT | POLLWRNORM))
 
 
 
 -- 
 Oliver Fromme,  secnetix GmbH & Co. KG, Marktplatz 29, 85567 Grafing
 Dienstleistungen mit Schwerpunkt FreeBSD: http://www.secnetix.de/bsd
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