From: Timo Sirainen <timo.sirainen@open-xchange.com>
Date: Wed, 6 Nov 2019 12:36:58 +0000 (+0200)
Subject: lib: Add net_set_tcp_quickack()
X-Git-Tag: 2.3.10~309
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=c3a3b210da852cb6e2a51d2759f0a58401c7270d;p=thirdparty%2Fdovecot%2Fcore.git

lib: Add net_set_tcp_quickack()
---

diff --git a/src/lib/net.c b/src/lib/net.c
index 25645c39bb..7eeed6319f 100644
--- a/src/lib/net.c
+++ b/src/lib/net.c
@@ -366,6 +366,18 @@ int net_set_tcp_nodelay(int fd, bool nodelay)
 	return setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &val, sizeof(val));
 }
 
+int net_set_tcp_quickack(int fd, bool quickack)
+{
+#ifdef TCP_QUICKACK
+	int val = quickack;
+
+	return setsockopt(fd, IPPROTO_TCP, TCP_QUICKACK, &val, sizeof(val));
+#else
+	errno = ENOPROTOOPT;
+	return -1;
+#endif
+}
+
 int net_set_send_buffer_size(int fd, size_t size)
 {
 	int opt;
diff --git a/src/lib/net.h b/src/lib/net.h
index 84d2f45b01..7f8abb7181 100644
--- a/src/lib/net.h
+++ b/src/lib/net.h
@@ -98,6 +98,10 @@ void net_set_nonblock(int fd, bool nonblock);
 int net_set_cork(int fd, bool cork) ATTR_NOWARN_UNUSED_RESULT;
 /* Set TCP_NODELAY, which disables the Nagle algorithm. */
 int net_set_tcp_nodelay(int fd, bool nodelay);
+/* Set TCP_QUICKACK, which tells the kernel to not delay ACKs. Note that the
+   kernel can (and will) re-enable delayed ACKs while processing the TCP stack.
+   This means that this function needs to be called repeatedly. */
+int net_set_tcp_quickack(int fd, bool quickack);
 
 /* Set socket kernel buffer sizes */
 int net_set_send_buffer_size(int fd, size_t size);