Waiting the remaining tcp data are sent

jerry-ext/debugger/debugger-tcp.c

@@ -144,6 +144,30 @@ jerryx_debugger_tcp_close (jerry_debugger_transport_header_t *header_p) /**< tcp
 
   jerryx_debugger_transport_tcp_t *tcp_p = (jerryx_debugger_transport_tcp_t *) header_p;
 
+  /* Waiting for the debug client close the tcp connection first. */
+  while (true)
+  {
+    char buf[8];
+    jerryx_socket_ssize_t result = recv (tcp_p->tcp_socket, buf, sizeof (buf), 0);
+    if (result == 0)
+    {
+      /**
+       * If result == 0, means the socket are closed by remote client, break the loop
+       */
+      break;
+    }
+    else if (result < 0 && jerryx_debugger_tcp_get_errno () != JERRYX_EWOULDBLOCK)
+    {
+      /* errno other than JERRYX_EWOULDBLOCK means socket have true error, break the loop */
+      break;
+    }
+    /**
+      * If result > 0, means that there is data available on the socket, waiting.
+      * If result < 0 and errno == JERRYX_EWOULDBLOCK, means have no data but
+      * the socket still available, waiting.
+      */
+  }
+
   JERRYX_DEBUG_MSG ("TCP connection closed.\n");
 
   jerryx_debugger_tcp_close_socket (tcp_p->tcp_socket);