From 25222e4abc1ac998242fe220113cea0c7bf1ed84 Mon Sep 17 00:00:00 2001
From: Stefan Lankes <lankes@lfbs.rwth-aachen.de>
Date: Sat, 17 Sep 2011 15:25:42 +0200
Subject: [PATCH] if LWIP_TCPIP_CORE_LOCKING is 0, we send a copy of the
 message to TCPIP thread

---
 drivers/char/socket.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/drivers/char/socket.c b/drivers/char/socket.c
index 10a745d5..60554822 100755
--- a/drivers/char/socket.c
+++ b/drivers/char/socket.c
@@ -58,7 +58,20 @@ static ssize_t socket_write(fildes_t* file, uint8_t* buffer, size_t size)
 {
 	int ret = 0;
 #if defined(CONFIG_LWIP) && LWIP_SOCKET
+	if (BUILTIN_EXPECT(!size, 0))
+		return 0;
+
+#if LWIP_TCPIP_CORE_LOCKING
 	ret = lwip_write(file->offset, buffer, size);
+#else
+	// create a copy and forward this copy to the TCP/IP stack
+	uint8_t* tmp = kmalloc(size);
+	if (BUILTIN_EXPECT(!tmp, 0))
+		return -ENOMEM;
+	memcpy(tmp, buffer, size);
+	ret = lwip_write(file->offset, tmp, size);
+	kfree(tmp, size);
+#endif
 	if (ret < 0)
 		ret = -errno;
 #endif