From 5af5fc44092c548ca6a5be56dcbdfb07f87a51a8 Mon Sep 17 00:00:00 2001
From: Gregory Nutt <gnutt@nuttx.org>
Date: Mon, 1 Jul 2019 07:37:41 -0600
Subject: [PATCH] net/inet/inet_close.c:  Last PR remove SO_LINGER socket
 option.  SO_LINGER was always enabled is CONFIG_NET_SOLINGER was selected.

---
 TODO                  | 21 ++-------------------
 net/inet/inet_close.c | 34 ++++++++++++++++++++++------------
 2 files changed, 24 insertions(+), 31 deletions(-)

diff --git a/TODO b/TODO
index 67587d1ab7..34b3a15671 100644
--- a/TODO
+++ b/TODO
@@ -1,4 +1,4 @@
-NuttX TODO List (Last updated April 29, 2019)
+NuttX TODO List (Last updated July 1, 2019)
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 This file summarizes known NuttX bugs, limitations, inconsistencies with
@@ -19,7 +19,7 @@ nuttx/:
   (9)  Kernel/Protected Build
   (3)  C++ Support
   (5)  Binary loaders (binfmt/)
- (18)  Network (net/, drivers/net)
+ (17)  Network (net/, drivers/net)
   (4)  USB (drivers/usbdev, drivers/usbhost)
   (2)  Other drivers (drivers/)
   (9)  Libraries (libs/libc/, libs/libm/)
@@ -1653,23 +1653,6 @@ o Network (net/, drivers/net)
                before, so I suspect it might not be so prevalent as one
                might expect.
 
-  Title:       TCP SOCKETS CLOSED TOO QUICKLY
-  Description: When a socket is closed, the resources are torn down
-               immediately (unless the SO_LINGER option is selected).  As a
-               result, the socket does not send the FIN and this looks like
-               an unexpected, abnormal loss of connection to the remote peer.
-
-               Actually, it is worse than this:  The is NO logic to send
-               FIN in when the file is close.  This is pretty easy to do,
-               however:
-
-                 - Wait for a TCP poll, then
-                 - Call tcp_append with TCP_CLOSE in the flags.  There is
-                   already logic in tcp_appsend to send the FIN in this case,
-                   it is just not being use.
-  Status:      Open
-  Priority:    Medium-Low.
-
   Title:       LOCAL DATAGRAM RECVFROM RETURNS WRONG SENDER ADDRESS
   Description: The recvfrom logic for local datagram sockets returns the
                incorrect sender "from" address.  Instead, it returns the
diff --git a/net/inet/inet_close.c b/net/inet/inet_close.c
index cdfd8f6836..5e587417e2 100644
--- a/net/inet/inet_close.c
+++ b/net/inet/inet_close.c
@@ -213,7 +213,6 @@ static uint16_t tcp_close_eventhandler(FAR struct net_driver_s *dev,
       pstate->cl_result = -ETIMEDOUT;
       goto end_wait;
     }
-
 #endif /* CONFIG_NET_SOLINGER */
 
 #ifdef CONFIG_NET_TCP_WRITE_BUFFERS
@@ -327,6 +326,7 @@ static inline int tcp_close_disconnect(FAR struct socket *psock)
   FAR struct tcp_conn_s *conn;
 #ifdef CONFIG_NET_SOLINGER
   struct timespec abstime;
+  bool linger;
 #endif
   int ret = OK;
 
@@ -400,21 +400,31 @@ static inline int tcp_close_disconnect(FAR struct socket *psock)
       /* Wait for the disconnect event */
 
 #ifdef CONFIG_NET_SOLINGER
-      DEBUGVERIFY(clock_gettime(CLOCK_REALTIME, &abstime));
+     /* A non-NULL value of the priv field means that lingering is
+      * enabled.
+      */
 
-      /* NOTE: s_linger's unit is deciseconds,
-       * so we don't need to update abstime.tv_nsec here.
-       */
-
-      abstime.tv_sec += psock->s_linger / DSEC_PER_SEC;
-
-      if (-ETIMEDOUT == net_timedwait(&state.cl_sem, &abstime))
+      linger = _SO_GETOPT(psock->s_options, SO_LINGER);
+      if (linger)
         {
-          state.cl_result = -ETIMEDOUT;
+          DEBUGVERIFY(clock_gettime(CLOCK_REALTIME, &abstime));
+
+          /* NOTE: s_linger's unit is deciseconds,
+           * so we don't need to update abstime.tv_nsec here.
+           */
+
+          abstime.tv_sec += psock->s_linger / DSEC_PER_SEC;
+
+          if (-ETIMEDOUT == net_timedwait(&state.cl_sem, &abstime))
+            {
+              state.cl_result = -ETIMEDOUT;
+            }
         }
+      else
 #else
-      (void)net_timedwait(&state.cl_sem, NULL);
-#endif
+        {
+          (void)net_timedwait(&state.cl_sem, NULL);
+        }
 
       /* We are now disconnected */