New thrift c++ error code

Summary: ALREADY_OPEN

Reviewed By: aditya


git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@665010 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/lib/cpp/src/transport/TSocket.cpp b/lib/cpp/src/transport/TSocket.cpp
index 58bb9f4..05fb35f 100644
--- a/lib/cpp/src/transport/TSocket.cpp
+++ b/lib/cpp/src/transport/TSocket.cpp
@@ -98,6 +98,10 @@
 }
 
 void TSocket::open() {
+  if (isOpen()) {
+    throw TTransportException(TTransportException::ALREADY_OPEN);
+  }
+
   // Create socket
   socket_ = socket(AF_INET, SOCK_STREAM, 0);
   if (socket_ == -1) {