From d662c1b73b6ee85b0743b19883bfc7606e3f6e6c Mon Sep 17 00:00:00 2001
From: Kyle Nekritz <knekritz@fb.com>
Date: Fri, 4 Dec 2015 09:18:44 -0800
Subject: [PATCH] Make getWrappedTransport/getUnderlyingTransport const.

Reviewed By: mzlee

Differential Revision: D2709222

fb-gh-sync-id: 67a00a49bbcef5572b6092d7bfba1842d985e643
---
 folly/io/async/AsyncTransport.h          | 14 ++++++++++----
 folly/io/async/test/MockAsyncTransport.h |  2 +-
 2 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/folly/io/async/AsyncTransport.h b/folly/io/async/AsyncTransport.h
index f9925d84..8fdbefce 100644
--- a/folly/io/async/AsyncTransport.h
+++ b/folly/io/async/AsyncTransport.h
@@ -543,7 +543,7 @@ class AsyncTransportWrapper : virtual public AsyncTransport,
    * transport that is wrapped. It returns nullptr if there is no wrapped
    * transport.
    */
-  virtual AsyncTransportWrapper* getWrappedTransport() {
+  virtual const AsyncTransportWrapper* getWrappedTransport() const {
     return nullptr;
   }
 
@@ -553,10 +553,10 @@ class AsyncTransportWrapper : virtual public AsyncTransport,
    * the derived classes of the underlying transport.
    */
   template <class T>
-  T* getUnderlyingTransport() {
-    AsyncTransportWrapper* current = this;
+  const T* getUnderlyingTransport() const {
+    const AsyncTransportWrapper* current = this;
     while (current) {
-      auto sock = dynamic_cast<T*>(current);
+      auto sock = dynamic_cast<const T*>(current);
       if (sock) {
         return sock;
       }
@@ -565,6 +565,12 @@ class AsyncTransportWrapper : virtual public AsyncTransport,
     return nullptr;
   }
 
+  template <class T>
+  T* getUnderlyingTransport() {
+    return const_cast<T*>(static_cast<const AsyncTransportWrapper*>(this)
+        ->getUnderlyingTransport<T>());
+  }
+
   /**
    * Return the application protocol being used by the underlying transport
    * protocol. This is useful for transports which are used to tunnel other
diff --git a/folly/io/async/test/MockAsyncTransport.h b/folly/io/async/test/MockAsyncTransport.h
index 1e987d3d..bd091056 100644
--- a/folly/io/async/test/MockAsyncTransport.h
+++ b/folly/io/async/test/MockAsyncTransport.h
@@ -77,7 +77,7 @@ class MockAsyncTransport: public AsyncTransportWrapper {
   MOCK_CONST_METHOD0(getRawBytesReceived, size_t());
   MOCK_CONST_METHOD0(isEorTrackingEnabled, bool());
   MOCK_METHOD1(setEorTracking, void(bool));
-  MOCK_METHOD0(getWrappedTransport, AsyncTransportWrapper*());
+  MOCK_CONST_METHOD0(getWrappedTransport, AsyncTransportWrapper*());
 
 };
 
-- 
2.34.1