[src/trunk]: src/sys/kern Fix a case where an erroneous EAGAIN was returned o...

[seanb <seanb%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/6557cec41baf
branches:  trunk
changeset: 795325:6557cec41baf
user:      seanb <seanb%NetBSD.org@localhost>
date:      Mon Apr 07 15:35:23 2014 +0000

description:
Fix a case where an erroneous EAGAIN was returned out of recvmmsg.
This occured when some, but not all of the mmsg array members
were filled with data from a non-blocking socket.
PR kern/48725

diffstat:

 sys/kern/uipc_syscalls.c |  9 ++++++---
 1 files changed, 6 insertions(+), 3 deletions(-)

diffs (31 lines):

diff -r e56db68accac -r 6557cec41baf sys/kern/uipc_syscalls.c
--- a/sys/kern/uipc_syscalls.c  Mon Apr 07 15:09:20 2014 +0000
+++ b/sys/kern/uipc_syscalls.c  Mon Apr 07 15:35:23 2014 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: uipc_syscalls.c,v 1.165 2013/10/09 20:15:39 christos Exp $     */
+/*     $NetBSD: uipc_syscalls.c,v 1.166 2014/04/07 15:35:23 seanb Exp $        */
 
 /*-
  * Copyright (c) 2008, 2009 The NetBSD Foundation, Inc.
@@ -61,7 +61,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: uipc_syscalls.c,v 1.165 2013/10/09 20:15:39 christos Exp $");
+__KERNEL_RCSID(0, "$NetBSD: uipc_syscalls.c,v 1.166 2014/04/07 15:35:23 seanb Exp $");
 
 #include "opt_pipe.h"
 
@@ -1058,8 +1058,11 @@
 
                error = do_sys_recvmsg_so(l, s, so, msg, &from,
                    msg->msg_control != NULL ? &control : NULL, retval);
-               if (error)
+               if (error) {
+                       if (error == EAGAIN && dg > 0)
+                               error = 0;
                        break;
+               }
 
                if (msg->msg_control != NULL)
                        error = copyout_msg_control(l, msg, control);