From: Samuel Thibault <samuel.thibault@eu.citrix.com>
Subject: [PATCH] stubdom: support select with NULL arguments
Date: Tue, 11 Mar 2008 17:38:09 +0000
Message-ID: <20080311173809.GE5831@implementation.uk.xensource.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Return-path: <xen-devel-bounces@lists.xensource.com>
Content-Disposition: inline
List-Unsubscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>,
	<mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
List-Post: <mailto:xen-devel@lists.xensource.com>
List-Help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-Subscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>,
	<mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
Sender: xen-devel-bounces@lists.xensource.com
Errors-To: xen-devel-bounces@lists.xensource.com
To: xen-devel@lists.xensource.com
List-Id: xen-devel@lists.xenproject.org

Add support for select() call with NULL arguments.

Signed-off-by: Samuel Thibault <samuel.thibault@eu.citrix.com>

diff -r 73ec21ad5dc7 extras/mini-os/lib/sys.c
--- a/extras/mini-os/lib/sys.c	Tue Mar 11 16:01:04 2008 +0000
+++ b/extras/mini-os/lib/sys.c	Tue Mar 11 17:35:14 2008 +0000
@@ -820,9 +820,19 @@
     add_waiter(w4, xenbus_watch_queue);
     add_waiter(w5, kbdfront_queue);
 
-    myread = *readfds;
-    mywrite = *writefds;
-    myexcept = *exceptfds;
+    if (readfds)
+        myread = *readfds;
+    else
+        FD_ZERO(&myread);
+    if (writefds)
+        mywrite = *writefds;
+    else
+        FD_ZERO(&mywrite);
+    if (exceptfds)
+        myexcept = *exceptfds;
+    else
+        FD_ZERO(&myexcept);
+
     DEBUG("polling ");
     dump_set(nfds, &myread, &mywrite, &myexcept, timeout);
     DEBUG("\n");
@@ -861,9 +871,19 @@
 	thread->wakeup_time = stop;
     schedule();
 
-    myread = *readfds;
-    mywrite = *writefds;
-    myexcept = *exceptfds;
+    if (readfds)
+        myread = *readfds;
+    else
+        FD_ZERO(&myread);
+    if (writefds)
+        mywrite = *writefds;
+    else
+        FD_ZERO(&mywrite);
+    if (exceptfds)
+        myexcept = *exceptfds;
+    else
+        FD_ZERO(&myexcept);
+
     n = select_poll(nfds, &myread, &mywrite, &myexcept);
 
     if (n) {