From f9ab8e266b93aa3be772374ef4a8fdb06e376568 Mon Sep 17 00:00:00 2001
From: Guus Sliepen <guus@tinc-vpn.org>
Date: Fri, 1 Mar 2013 17:15:26 +0100
Subject: [PATCH] Flush output buffers in the tap reader thread on Windows.

This is basically a port of commit 50fcfea1 to 1.1.
---
 src/event.c        | 6 ++++++
 src/event.h        | 1 +
 src/mingw/device.c | 1 +
 src/net_socket.c   | 3 +++
 4 files changed, 11 insertions(+)

diff --git a/src/event.c b/src/event.c
index 6b730f6d..095e7c33 100644
--- a/src/event.c
+++ b/src/event.c
@@ -245,6 +245,12 @@ bool event_loop(void) {
 	return true;
 }
 
+void event_flush_output(void) {
+	for splay_each(io_t, io, &io_tree)
+		if(FD_ISSET(io->fd, &writefds))
+			io->cb(io->data, IO_WRITE);
+}
+
 void event_exit(void) {
 	running = false;
 }
diff --git a/src/event.h b/src/event.h
index d0129d0c..bd91b7b9 100644
--- a/src/event.h
+++ b/src/event.h
@@ -65,6 +65,7 @@ extern void signal_add(signal_t *sig, signal_cb_t cb, void *data, int signum);
 extern void signal_del(signal_t *sig);
 
 extern bool event_loop(void);
+extern void event_flush_output(void);
 extern void event_exit(void);
 
 #endif
diff --git a/src/mingw/device.c b/src/mingw/device.c
index aa059720..ac83d8c3 100644
--- a/src/mingw/device.c
+++ b/src/mingw/device.c
@@ -80,6 +80,7 @@ static DWORD WINAPI tapreader(void *bla) {
 		packet.len = len;
 		packet.priority = 0;
 		route(myself, &packet);
+		event_flush_output();
 		LeaveCriticalSection(&mutex);
 	}
 }
diff --git a/src/net_socket.c b/src/net_socket.c
index a28be54a..0ee36553 100644
--- a/src/net_socket.c
+++ b/src/net_socket.c
@@ -349,6 +349,9 @@ static void do_outgoing_pipe(connection_t *c, char *command) {
 }
 
 static void handle_meta_write(connection_t *c) {
+	if(c->outbuf.len <= c->outbuf.offset)
+		return;
+
 	ssize_t outlen = send(c->socket, c->outbuf.data + c->outbuf.offset, c->outbuf.len - c->outbuf.offset, 0);
 	if(outlen <= 0) {
 		if(!errno || errno == EPIPE) {