From f69b52b1aa5b196da5104c5dfac81e2de1eb5e53 Mon Sep 17 00:00:00 2001
From: Tatsuhiro Tsujikawa <tatsuhiro.t@gmail.com>
Date: Sat, 18 Mar 2017 00:59:26 +0900
Subject: [PATCH] nghttpx: Attempt to avoid TCP RST on socket closure on Linux

---
 src/shrpx_connection.cc | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/src/shrpx_connection.cc b/src/shrpx_connection.cc
index a19757a1..a4d4c598 100644
--- a/src/shrpx_connection.cc
+++ b/src/shrpx_connection.cc
@@ -126,7 +126,20 @@ void Connection::disconnect() {
   }
 
   if (fd != -1) {
-    shutdown(fd, SHUT_WR);
+    // At least for Linux, shutdown both sides, and continue to read
+    // until it gets EOF or error in order to avoid TCP RST.
+    shutdown(fd, SHUT_RDWR);
+#ifdef __linux__
+    std::array<uint8_t, 16_k> b;
+    for (;;) {
+      ssize_t n;
+      while ((n = read(fd, b.data(), b.size())) == -1 && errno == EINTR)
+        ;
+      if (n <= 0) {
+        break;
+      }
+    }
+#endif // __linux__
     close(fd);
     fd = -1;
   }