when a buffer has a file descriptor to pass attached, we tried to send

out all pending buffers up to and including the one with the fd attached.
the fd is sent with the data and closed after all data is sent.
when this amount of data exceeds what we can get rid of with a single
sendmsg() on our nonblocking sockets we might send the fd more than
once, leaving unused fds around.
when we see a buffer with an fd attached, send out everything up to, but
EXcluding that buffer, so that in the next round a seperate message with
just the one buffer and the associated fd is sent. if anything got
written in that sendmsg() call consider the fd sent and close it. from
a debugging session with theo hunting something else, claudio ok

1 files changed, 8 insertions, 1 deletions

diff --git a/usr.sbin/bgpd/buffer.c b/usr.sbin/bgpd/buffer.c
index a0e196ca0bb..40de87e4fb6 100644
--- a/usr.sbin/bgpd/buffer.c
+++ b/usr.sbin/bgpd/buffer.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: buffer.c,v 1.26 2005/02/01 21:36:02 henning Exp $ */
+/*	$OpenBSD: buffer.c,v 1.27 2005/03/14 11:59:13 henning Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -151,6 +151,8 @@ msgbuf_write(struct msgbuf *msgbuf)
 	TAILQ_FOREACH(buf, &msgbuf->bufs, entry) {
 		if (i >= IOV_MAX)
 			break;
+		if (i != 0 && buf->fd != -1)	/* fds on their own */
+			break;
 		iov[i].iov_base = buf->buf + buf->rpos;
 		iov[i].iov_len = buf->size - buf->rpos;
 		i++;
@@ -192,6 +194,11 @@ msgbuf_write(struct msgbuf *msgbuf)
 		} else {
 			buf->rpos += n;
 			n = 0;
+			/* assumption: fd got sent if sendmsg sent anything */
+			if (buf->fd != -1) {
+				close(buf->fd);
+				buf->fd = -1;
+			}
 		}
 	}