From e599e35469f0385359ad8aff07d86a9d51beefc4 Mon Sep 17 00:00:00 2001
From: kevin <kevin@larke.org>
Date: Tue, 4 Jul 2023 12:02:13 -0400
Subject: [PATCH] cwSocket.cpp,cwSocketDecls.h,cwIo.cpp : Implement
 TCP_NODELAY.

---
 cwIo.cpp        |  1 +
 cwSocket.cpp    | 13 +++++++++++++
 cwSocketDecls.h |  1 +
 3 files changed, 15 insertions(+)

diff --git a/cwIo.cpp b/cwIo.cpp
index 97eefd2..d4a0356 100644
--- a/cwIo.cpp
+++ b/cwIo.cpp
@@ -714,6 +714,7 @@ namespace cw
           { .id=sock::kMultiCastLoopFl, .label="multicast_loop" }, //
           { .id=sock::kListenFl,        .label="listen"         }, // Use this socket to listen for incoming connections
           { .id=sock::kStreamFl,        .label="stream"         }, // Connected stream (vs. Datagram)
+          { .id=sock::kTcpNoDelayFl,    .label="tcp_no_delay"   }, // Implements TCP_NODELAY
           { .id=0,                      .label=nullptr,         }
         };
 
diff --git a/cwSocket.cpp b/cwSocket.cpp
index b50ee47..ae3b391 100644
--- a/cwSocket.cpp
+++ b/cwSocket.cpp
@@ -8,6 +8,7 @@
 #include <sys/ioctl.h>
 #include <net/if.h>
 #include <netinet/in.h>	
+#include <netinet/tcp.h>
 #include <arpa/inet.h>	
 #include <fcntl.h>		
 #include <unistd.h>  // close
@@ -502,6 +503,7 @@ namespace cw
         goto errLabel;
       }
 
+
     errLabel:
       return rc;
     }
@@ -740,6 +742,17 @@ cw::rc_t cw::sock::create( handle_t h,
       goto errLabel;
     }
   }
+
+  if( cwIsFlag(flags,kTcpFl) && cwIsFlag(flags,kTcpNoDelayFl) )
+  {
+    int nodelay_flag = 1;
+    if( setsockopt( s->sockH, IPPROTO_TCP, TCP_NODELAY, (void *)&nodelay_flag, sizeof(nodelay_flag)) == cwSOCKET_SYS_ERR )
+    {
+      rc = cwLogSysError(kOpFailRC,errno, "Attempt to set the socket NODELAY attribute failed." );
+      goto errLabel;      
+    }
+    
+  }
   
   // create the 32 bit local address		
   if((rc = _initAddr( localAddr, port,  &s->localSockAddr )) != kOkRC )
diff --git a/cwSocketDecls.h b/cwSocketDecls.h
index 4a23c56..f4bd2b6 100644
--- a/cwSocketDecls.h
+++ b/cwSocketDecls.h
@@ -28,6 +28,7 @@ namespace cw
      kMultiCastLoopFl = 0x040,  //
      kListenFl        = 0x080,  // Use this socket to listen for incoming connections
      kStreamFl        = 0x100,  // Connected stream (not Datagram)
+     kTcpNoDelayFl    = 0x200,  // TCP stream option only (Implements TCP_NODELAY)
     };
 
     enum