Add the ability to set the event EventRecvmsgCallback

Summary: Add the ability to set the event EventRecvmsgCallback

Reviewed By: danobi

Differential Revision: D22959687

fbshipit-source-id: 274cecf4ab4b8015d5e7e725c7e899f603cea7a0

folly/io/async/AsyncSocket.h

@@ -503,6 +503,13 @@ class AsyncSocket : public AsyncTransport {
   // Read and write methods
   void setReadCB(ReadCallback* callback) override;
   ReadCallback* getReadCallback() const override;
+  void setEventCallback(EventRecvmsgCallback* cb) override {
+    if (cb) {
+      ioHandler_.setEventCallback(cb);
+    } else {
+      ioHandler_.resetEventCallback();
+    }
+  }
 
   bool setZeroCopy(bool enable) override;
   bool getZeroCopy() const override {

folly/io/async/AsyncTransport.h

@@ -266,6 +266,7 @@ class AsyncReader {
   // Read methods that aren't part of AsyncTransport.
   virtual void setReadCB(ReadCallback* callback) = 0;
   virtual ReadCallback* getReadCallback() const = 0;
+  virtual void setEventCallback(EventRecvmsgCallback* /*cb*/) {}
 
  protected:
   virtual ~AsyncReader() = default;