sdevent: Support getting userdata

Will be needed when we start storing the userdata on the heap

Change-Id: I31d2c2b6741d0a4422a79b4d0a752d352121ae3c
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/src/sdeventplus/internal/sdevent.cpp b/src/sdeventplus/internal/sdevent.cpp
index 6d8cde9..ece6b50 100644
--- a/src/sdeventplus/internal/sdevent.cpp
+++ b/src/sdeventplus/internal/sdevent.cpp
@@ -127,6 +127,11 @@
     return ::sd_event_source_unref(source);
 }
 
+void* SdEventImpl::sd_event_source_get_userdata(sd_event_source* source) const
+{
+    return ::sd_event_source_get_userdata(source);
+}
+
 void* SdEventImpl::sd_event_source_set_userdata(sd_event_source* source,
                                                 void* userdata) const
 {
diff --git a/src/sdeventplus/internal/sdevent.hpp b/src/sdeventplus/internal/sdevent.hpp
index f90e06b..e69b2fd 100644
--- a/src/sdeventplus/internal/sdevent.hpp
+++ b/src/sdeventplus/internal/sdevent.hpp
@@ -64,6 +64,8 @@
     virtual sd_event_source*
         sd_event_source_unref(sd_event_source* source) const = 0;
 
+    virtual void*
+        sd_event_source_get_userdata(sd_event_source* source) const = 0;
     virtual void* sd_event_source_set_userdata(sd_event_source* source,
                                                void* userdata) const = 0;
 
@@ -171,6 +173,7 @@
     sd_event_source*
         sd_event_source_unref(sd_event_source* source) const override;
 
+    void* sd_event_source_get_userdata(sd_event_source* source) const override;
     void* sd_event_source_set_userdata(sd_event_source* source,
                                        void* userdata) const override;
 
diff --git a/src/sdeventplus/test/sdevent.hpp b/src/sdeventplus/test/sdevent.hpp
index 366cb67..6e78169 100644
--- a/src/sdeventplus/test/sdevent.hpp
+++ b/src/sdeventplus/test/sdevent.hpp
@@ -57,6 +57,7 @@
     MOCK_CONST_METHOD1(sd_event_source_unref,
                        sd_event_source*(sd_event_source*));
 
+    MOCK_CONST_METHOD1(sd_event_source_get_userdata, void*(sd_event_source*));
     MOCK_CONST_METHOD2(sd_event_source_set_userdata,
                        void*(sd_event_source*, void*));