Invoke optional callback function on timer expiration

When the timer expires, it calls into it's own timeout
handler which matches with sd_event callback handler.

However, it is beneficial if the users of timer register
their own callback routine so that they can execute some
operations on timeout.

Change-Id: Ia88cb4e3c17f6dd8d4528fa193ec7927f083a92b
Signed-off-by: Vishwanatha Subbanna <vishwa@linux.vnet.ibm.com>

1 files changed, 7 insertions, 3 deletions

diff --git a/timer.cpp b/timer.cpp
index bf1a470..c98dcb0 100644
--- a/timer.cpp
+++ b/timer.cpp
@@ -44,12 +44,16 @@ int Timer::timeoutHandler(sd_event_source* eventSource,
 {
     using namespace phosphor::logging;
 
+    log<level::INFO>("Timer Expired");
+
     auto timer = static_cast<Timer*>(userData);
     timer->expire = true;
 
-    log<level::INFO>("Timer Expired");
-
-    //TODO: Need to call user callback function.
+    // Call an optional callback function
+    if(timer->userCallBack)
+    {
+        timer->userCallBack();
+    }
     return 0;
 }