From 6432ce2ec15b0c45691f6a3c288234c8ccd13467 Mon Sep 17 00:00:00 2001
From: Emiel Bruijntjes <emiel.bruijntjes@copernica.com>
Date: Mon, 12 Nov 2018 15:19:31 +0100
Subject: [PATCH] added connection::usable()

---
 include/amqpcpp/connection.h              | 10 ++++++++++
 include/amqpcpp/connectionimpl.h          |  9 +++++++++
 include/amqpcpp/linux_tcp/tcpconnection.h |  9 +++++++++
 3 files changed, 28 insertions(+)

diff --git a/include/amqpcpp/connection.h b/include/amqpcpp/connection.h
index 99edc33..ade2c3b 100644
--- a/include/amqpcpp/connection.h
+++ b/include/amqpcpp/connection.h
@@ -195,6 +195,16 @@ public:
     {
         return _implementation.expected();
     }
+    
+    /**
+     *  Is the connection in a usable state, or is it already closed or
+     *  in the process of being closed?
+     *  @return bool
+     */
+    bool usable() const
+    {
+        return _implementation.usable();
+    }
 
     /**
      *  Close the connection
diff --git a/include/amqpcpp/connectionimpl.h b/include/amqpcpp/connectionimpl.h
index bdd79c0..7f8e1b7 100644
--- a/include/amqpcpp/connectionimpl.h
+++ b/include/amqpcpp/connectionimpl.h
@@ -252,6 +252,15 @@ public:
         // state must be connected
         return _state == state_closed;
     }
+    
+    /**
+     *  Is the connection in a usable state / not yet closed?
+     *  @return bool
+     */
+    bool usable() const
+    {
+        return (_state == state_protocol || _state == state_handshake || _state == state_connected) && !_closed;
+    }
 
     /**
      *  Mark the connection as ready
diff --git a/include/amqpcpp/linux_tcp/tcpconnection.h b/include/amqpcpp/linux_tcp/tcpconnection.h
index 3c48170..dd1aabd 100644
--- a/include/amqpcpp/linux_tcp/tcpconnection.h
+++ b/include/amqpcpp/linux_tcp/tcpconnection.h
@@ -236,6 +236,15 @@ public:
      */
     bool close(bool immediate = false);
     
+    /**
+     *  Is the connection in a usable state / not yet closed or being closed
+     *  @return bool
+     */
+    bool usable() const
+    {
+        return _connection.usable();
+    }
+    
     /**
      *  The max frame size. Useful if you set up a buffer to parse incoming data: it does not have to exceed this size.
      *  @return uint32_t