From: Wouter Wijngaards <wouter@nlnetlabs.nl>
Date: Mon, 15 Feb 2016 09:54:52 +0000 (+0000)
Subject: - wait for sendto to drain socket buffers when they are full.
X-Git-Tag: release-1.5.8~15
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9eeb489243cf2368df52adffeb86507a4f335a6d;p=thirdparty%2Funbound.git

- wait for sendto to drain socket buffers when they are full.


git-svn-id: file:///svn/unbound/trunk@3624 be551aaa-1e26-0410-a405-d3ace91eadb9
---

diff --git a/doc/Changelog b/doc/Changelog
index 2ad8ae409..b290fbe40 100644
--- a/doc/Changelog
+++ b/doc/Changelog
@@ -1,5 +1,6 @@
 15 February 2016: Wouter
 	- ip-transparent option for FreeBSD with IP_BINDANY socket option.
+	- wait for sendto to drain socket buffers when they are full.
 
 9 February 2016: Wouter
 	- Test for type OPENPGPKEY.
diff --git a/util/netevent.c b/util/netevent.c
index d7ab218aa..b827e6540 100644
--- a/util/netevent.c
+++ b/util/netevent.c
@@ -400,6 +400,31 @@ comm_point_send_udp_msg(struct comm_point *c, sldns_buffer* packet,
 	sent = sendto(c->fd, (void*)sldns_buffer_begin(packet), 
 		sldns_buffer_remaining(packet), 0,
 		addr, addrlen);
+	if(sent == -1) {
+		/* try again and block, waiting for IO to complete,
+		 * we want to send the answer, and we will wait for
+		 * the ethernet interface buffer to have space. */
+#ifndef USE_WINSOCK
+		if(errno == EAGAIN || 
+#  ifdef EWOULDBLOCK
+			errno == EWOULDBLOCK ||
+#  endif
+			errno == ENOBUFS) {
+#else
+		if(WSAGetLastError() == WSAEINPROGRESS ||
+			WSAGetLastError() == WSAENOBUFS ||
+			WSAGetLastError() == WSAEWOULDBLOCK) {
+#endif
+			int e;
+			fd_set_block(c->fd);
+			sent = sendto(c->fd, (void*)sldns_buffer_begin(packet), 
+				sldns_buffer_remaining(packet), 0,
+				addr, addrlen);
+			e = errno;
+			fd_set_nonblock(c->fd);
+			errno = e;
+		}
+	}
 	if(sent == -1) {
 		if(!udp_send_errno_needs_log(addr, addrlen))
 			return 0;
@@ -553,6 +578,29 @@ comm_point_send_udp_msg_if(struct comm_point *c, sldns_buffer* packet,
 	if(verbosity >= VERB_ALGO)
 		p_ancil("send_udp over interface", r);
 	sent = sendmsg(c->fd, &msg, 0);
+	if(sent == -1) {
+		/* try again and block, waiting for IO to complete,
+		 * we want to send the answer, and we will wait for
+		 * the ethernet interface buffer to have space. */
+#ifndef USE_WINSOCK
+		if(errno == EAGAIN || 
+#  ifdef EWOULDBLOCK
+			errno == EWOULDBLOCK ||
+#  endif
+			errno == ENOBUFS) {
+#else
+		if(WSAGetLastError() == WSAEINPROGRESS ||
+			WSAGetLastError() == WSAENOBUFS ||
+			WSAGetLastError() == WSAEWOULDBLOCK) {
+#endif
+			int e;
+			fd_set_block(c->fd);
+			sent = sendmsg(c->fd, &msg, 0);
+			e = errno;
+			fd_set_nonblock(c->fd);
+			errno = e;
+		}
+	}
 	if(sent == -1) {
 		if(!udp_send_errno_needs_log(addr, addrlen))
 			return 0;