From 55b8446528ad3915b3d28bdedd88c68f7334920f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=D0=A0=D1=83=D1=81=D0=BB=D0=B0=D0=BD=20=D0=98=D0=B6=D0=B1=D1?=
 =?UTF-8?q?=83=D0=BB=D0=B0=D1=82=D0=BE=D0=B2?= <lrn1986@gmail.com>
Date: Sun, 19 Jun 2011 21:44:43 +0400
Subject: [PATCH] Reduce server-client socket buffer size to 0

to make sure that SHUTDOWN_ACK reaches the other end before the process
terminates.
---
 src/arm/gnunet-service-arm.c        |    7 +++++++
 src/include/gnunet_connection_lib.h |   11 +++++++++++
 src/include/gnunet_network_lib.h    |    7 +++++++
 src/include/gnunet_server_lib.h     |    9 +++++++++
 src/util/connection.c               |   12 ++++++++++++
 src/util/network.c                  |   20 ++++++++++++++++++++
 src/util/server.c                   |   12 ++++++++++++
 7 files changed, 78 insertions(+), 0 deletions(-)

diff --git a/src/arm/gnunet-service-arm.c b/src/arm/gnunet-service-arm.c
index e357668..fa3caa3 100644
--- a/src/arm/gnunet-service-arm.c
+++ b/src/arm/gnunet-service-arm.c
@@ -958,6 +958,13 @@ transmit_shutdown_ack (void *cls, size_t size, void *buf)
   GNUNET_log (GNUNET_ERROR_TYPE_INFO,
               _("Transmitting shutdown ACK.\n"));
 
+#if defined (WINDOWS)
+  /* Make the connection flushing for the purpose of ACK transmitting */
+  if (GNUNET_OK != GNUNET_SERVER_client_set_flushing (client))
+    GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+        _("Failed to make the client connection flushing.\n"));
+#endif
+
   msg = (struct GNUNET_MessageHeader *) buf;
   msg->type = htons (GNUNET_MESSAGE_TYPE_ARM_SHUTDOWN_ACK);
   msg->size = htons (sizeof (struct GNUNET_MessageHeader));
diff --git a/src/include/gnunet_connection_lib.h b/src/include/gnunet_connection_lib.h
index 8d2dbb6..d080852 100644
--- a/src/include/gnunet_connection_lib.h
+++ b/src/include/gnunet_connection_lib.h
@@ -114,6 +114,17 @@ void
 GNUNET_CONNECTION_persist_(struct GNUNET_CONNECTION_Handle *sock);
 
 /**
+ * Make the connection flush itself and be blocking.
+ * Used to make sure that the last messages sent through the connection
+ * reach the other side before the process is terminated.
+ *
+ * @param sock the connection to make flushing and blocking
+ */
+int
+GNUNET_CONNECTION_set_flushing (struct GNUNET_CONNECTION_Handle *sock);
+
+
+/**
  * Create a socket handle by boxing an existing OS socket.  The OS
  * socket should henceforth be no longer used directly.
  * GNUNET_socket_destroy will close it.
diff --git a/src/include/gnunet_network_lib.h b/src/include/gnunet_network_lib.h
index 34cb7bc..3afb403 100644
--- a/src/include/gnunet_network_lib.h
+++ b/src/include/gnunet_network_lib.h
@@ -240,6 +240,13 @@ int GNUNET_NETWORK_socket_setsockopt (struct GNUNET_NETWORK_Handle *fd,
 int GNUNET_NETWORK_socket_shutdown (struct GNUNET_NETWORK_Handle *desc,
                                     int how);
 
+/**
+ * Reduce send and recv buffers to zero, flushing the socket.
+ * @param desc socket
+ * @return GNUNET_OK on success, GNUNET_SYSERR otherwise
+ */
+int GNUNET_NETWORK_socket_empty (struct GNUNET_NETWORK_Handle *desc);
+
 
 /**
  * Create a new socket.   Configure it for non-blocking IO and
diff --git a/src/include/gnunet_server_lib.h b/src/include/gnunet_server_lib.h
index ca20419..281a868 100644
--- a/src/include/gnunet_server_lib.h
+++ b/src/include/gnunet_server_lib.h
@@ -384,6 +384,15 @@ GNUNET_SERVER_ignore_shutdown (struct GNUNET_SERVER_Handle *h,
 
 
 /**
+ * FIXME
+ *
+ * @param sock handle to the service connection
+ */
+int
+GNUNET_SERVER_client_set_flushing (struct GNUNET_SERVER_Client *client);
+
+
+/**
  * The tansmit context is the key datastructure for a conveniance API
  * used for transmission of complex results to the client followed
  * ONLY by signaling receive_done with success or error
diff --git a/src/util/connection.c b/src/util/connection.c
index 6cb3495..c7bf325 100644
--- a/src/util/connection.c
+++ b/src/util/connection.c
@@ -302,6 +302,18 @@ void GNUNET_CONNECTION_persist_(struct GNUNET_CONNECTION_Handle *sock)
 }
 
 /**
+ * Make the connection flush itself and be blocking.
+ * Used to make sure that the last messages sent through the connection
+ * reach the other side before the process is terminated.
+ *
+ * @param sock the connection to make flushing and blocking
+ */
+int GNUNET_CONNECTION_set_flushing (struct GNUNET_CONNECTION_Handle *sock)
+{
+  return GNUNET_NETWORK_socket_empty (sock->sock);
+}
+
+/**
  * Create a socket handle by boxing an existing OS socket.  The OS
  * socket should henceforth be no longer used directly.
  * GNUNET_socket_destroy will close it.
diff --git a/src/util/network.c b/src/util/network.c
index 5ff49b1..c5cef24 100644
--- a/src/util/network.c
+++ b/src/util/network.c
@@ -721,6 +721,26 @@ GNUNET_NETWORK_socket_shutdown (struct GNUNET_NETWORK_Handle *desc, int how)
 
 
 /**
+ * Reduce send and recv buffers to zero, flushing the socket.
+ * @param desc socket
+ * @return GNUNET_OK on success, GNUNET_SYSERR otherwise
+ */
+int
+GNUNET_NETWORK_socket_empty (struct GNUNET_NETWORK_Handle *desc)
+{
+  int value = 0;
+  int ret = 0;
+
+  if (0 != (ret = setsockopt (desc->fd, SOL_SOCKET, SO_SNDBUF, &value, sizeof (value))))
+    GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "setsockopt");
+  if (0 != (ret = setsockopt (desc->fd, SOL_SOCKET, SO_RCVBUF, &value, sizeof (value))))
+    GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "setsockopt");
+
+  return ret == 0 ? GNUNET_OK : GNUNET_SYSERR;
+}
+
+
+/**
  * Reset FD set
  * @param fds fd set
  */
diff --git a/src/util/server.c b/src/util/server.c
index 03cf48f..1282864 100644
--- a/src/util/server.c
+++ b/src/util/server.c
@@ -1154,6 +1154,18 @@ GNUNET_SERVER_client_disconnect (struct GNUNET_SERVER_Client *client)
 
 
 /**
+ * FIXME
+ *
+ * @param sock handle to the service connection
+ */
+int
+GNUNET_SERVER_client_set_flushing (struct GNUNET_SERVER_Client *client)
+{
+  return GNUNET_CONNECTION_set_flushing (client->connection);
+}
+
+
+/**
  * Notify us when the server has enough space to transmit
  * a message of the given size to the given client.
  *
-- 
1.7.4