From: Timo Sirainen <timo.sirainen@dovecot.fi>
Date: Sun, 29 Oct 2017 21:28:38 +0000 (+0200)
Subject: lib: iostream-pump - Cork the ostream when writing
X-Git-Tag: 2.3.0.rc1~663
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=84b746f56209d4a85af73cd26850e75f519ae0b0;p=thirdparty%2Fdovecot%2Fcore.git

lib: iostream-pump - Cork the ostream when writing

This reduces latency for TCP connections by disabling Nagle algorithm.
---

diff --git a/src/lib/iostream-pump.c b/src/lib/iostream-pump.c
index 1d3901187d..b725af958d 100644
--- a/src/lib/iostream-pump.c
+++ b/src/lib/iostream-pump.c
@@ -28,12 +28,14 @@ void iostream_pump_copy(struct iostream_pump *pump)
 {
 	enum ostream_send_istream_result res;
 
+	o_stream_cork(pump->output);
 	size_t old_size = o_stream_get_max_buffer_size(pump->output);
 	o_stream_set_max_buffer_size(pump->output,
 				     I_MIN(IO_BLOCK_SIZE,
 					   o_stream_get_max_buffer_size(pump->output)));
 	res = o_stream_send_istream(pump->output, pump->input);
 	o_stream_set_max_buffer_size(pump->output, old_size);
+	o_stream_uncork(pump->output);
 
 	switch(res) {
 	case OSTREAM_SEND_ISTREAM_RESULT_ERROR_INPUT:
diff --git a/src/lib/test-iostream-pump.c b/src/lib/test-iostream-pump.c
index 95135c20a4..8650c3dd24 100644
--- a/src/lib/test-iostream-pump.c
+++ b/src/lib/test-iostream-pump.c
@@ -105,6 +105,8 @@ const char *run_pump(struct istream *in, struct ostream *out, int *counter, buff
 		/* input failed, finish flushing output */
 		test_ostream_set_max_output_size(ctx.out, (size_t)-1);
 		test_assert(o_stream_flush(ctx.out) > 0);
+	} else {
+		test_assert(o_stream_flush(ctx.out) != 0);
 	}
 
 	const char *ret = t_strdup(str_c(out_buffer));