From 4ffd067ac04c692ffe91cdff6a81fa5a189e73aa Mon Sep 17 00:00:00 2001
From: Davis King <davis@dlib.net>
Date: Sat, 20 Oct 2012 15:30:37 -0400
Subject: [PATCH] Added connection::disable_nagle()

---
 dlib/sockets/sockets_kernel_1.cpp      | 14 ++++++++++++++
 dlib/sockets/sockets_kernel_1.h        |  3 +++
 dlib/sockets/sockets_kernel_2.cpp      | 15 +++++++++++++++
 dlib/sockets/sockets_kernel_2.h        |  3 +++
 dlib/sockets/sockets_kernel_abstract.h | 13 +++++++++++++
 5 files changed, 48 insertions(+)

diff --git a/dlib/sockets/sockets_kernel_1.cpp b/dlib/sockets/sockets_kernel_1.cpp
index 6cf3aebff..999c995b5 100644
--- a/dlib/sockets/sockets_kernel_1.cpp
+++ b/dlib/sockets/sockets_kernel_1.cpp
@@ -266,6 +266,20 @@ namespace dlib
         delete &connection_socket;
     }
 
+// ----------------------------------------------------------------------------------------
+
+    int connection::
+    disable_nagle()
+    {
+        int flag = 1;
+        int status = setsockopt( connection_socket, IPPROTO_TCP, TCP_NODELAY, (char *)&flag, sizeof(flag) );
+
+        if (ret == SOCKET_ERROR) 
+            return OTHER_ERROR;
+        else
+            return 0;
+    }
+
 // ----------------------------------------------------------------------------------------
 
     long connection::
diff --git a/dlib/sockets/sockets_kernel_1.h b/dlib/sockets/sockets_kernel_1.h
index 2ed36a65a..e3e49c018 100644
--- a/dlib/sockets/sockets_kernel_1.h
+++ b/dlib/sockets/sockets_kernel_1.h
@@ -141,6 +141,9 @@ namespace dlib
         // as the SOCKET win the windows API.
         typedef unsigned_type<void*>::type socket_descriptor_type;
 
+        int disable_nagle(
+        );
+
         socket_descriptor_type get_socket_descriptor (
         ) const;
 
diff --git a/dlib/sockets/sockets_kernel_2.cpp b/dlib/sockets/sockets_kernel_2.cpp
index 248db4de9..4a84c9b1c 100644
--- a/dlib/sockets/sockets_kernel_2.cpp
+++ b/dlib/sockets/sockets_kernel_2.cpp
@@ -11,6 +11,7 @@
 #include "sockets_kernel_2.h"
 #include <fcntl.h>
 #include "../set.h"
+#include <netinet/tcp.h>
 
 
 
@@ -309,6 +310,20 @@ namespace dlib
         sdr(0)
     {}
 
+// ----------------------------------------------------------------------------------------
+
+    int connection::
+    disable_nagle()
+    {
+        int flag = 1;
+        if(setsockopt( connection_socket, IPPROTO_TCP, TCP_NODELAY, (char *)&flag, sizeof(flag) ))
+        {
+            return OTHER_ERROR;
+        }
+
+        return 0;
+    }
+
 // ----------------------------------------------------------------------------------------
 
     long connection::
diff --git a/dlib/sockets/sockets_kernel_2.h b/dlib/sockets/sockets_kernel_2.h
index 3d9282fea..d1be8e23d 100644
--- a/dlib/sockets/sockets_kernel_2.h
+++ b/dlib/sockets/sockets_kernel_2.h
@@ -183,6 +183,9 @@ namespace dlib
             return temp;
         }
 
+        int disable_nagle(
+        );
+
         typedef int socket_descriptor_type;
 
         socket_descriptor_type get_socket_descriptor (
diff --git a/dlib/sockets/sockets_kernel_abstract.h b/dlib/sockets/sockets_kernel_abstract.h
index 6fdfdc4d7..0d7217588 100644
--- a/dlib/sockets/sockets_kernel_abstract.h
+++ b/dlib/sockets/sockets_kernel_abstract.h
@@ -362,6 +362,19 @@ namespace dlib
                 - returns OTHER_ERROR if there was an error 
         !*/
 
+        int disable_nagle(
+        );
+        /*!
+            ensures
+                - Sets the TCP_NODELAY socket option to disable Nagle's algorithm.
+                  This can sometimes reduce transmission latency, however, in almost
+                  all normal cases you don't want to mess with this as the default
+                  setting is usually appropriate.  
+
+                - returns 0 upon success
+                - returns OTHER_ERROR if there was an error 
+        !*/
+
         typedef platform_specific_type socket_descriptor_type;
         socket_descriptor_type get_socket_descriptor (
         ) const;