Link watches to callbacks

Callbacks must ultimately be triggered when a property
is updated by a watch.  Add that support.

Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
Change-Id: I20130a11c19ddcf2c4ae45800f2068b31950bcd6

1 files changed, 14 insertions, 5 deletions

diff --git a/src/propertywatch.hpp b/src/propertywatch.hpp
index 59db599..3eb05df 100644
--- a/src/propertywatch.hpp
+++ b/src/propertywatch.hpp
@@ -17,6 +17,8 @@ namespace dbus
 namespace monitoring
 {
 
+class Callback;
+
 /** @class PropertyWatch
  *  @brief Type agnostic, factored out logic for property watches.
  *
@@ -33,8 +35,10 @@ class PropertyWatch : public Watch
         PropertyWatch& operator=(const PropertyWatch&) = delete;
         PropertyWatch& operator=(PropertyWatch&&) = default;
         virtual ~PropertyWatch() = default;
-        explicit PropertyWatch(const PropertyIndex& watchIndex)
-            : Watch(), index(watchIndex), alreadyRan(false) {}
+        PropertyWatch(
+            const PropertyIndex& watchIndex,
+            Callback* cb = nullptr)
+            : Watch(), index(watchIndex), callback(cb), alreadyRan(false) {}
 
         /** @brief Start the watch.
          *
@@ -84,7 +88,8 @@ class PropertyWatch : public Watch
         /** @brief Property names and their associated storage. */
         const PropertyIndex& index;
 
-    private:
+        /** @brief Optional callback method. */
+        Callback* const callback;
 
         /** @brief The start method should only be invoked once. */
         bool alreadyRan;
@@ -106,9 +111,13 @@ class PropertyWatchOfType : public PropertyWatch<DBusInterfaceType>
         PropertyWatchOfType& operator=(const PropertyWatchOfType&) = delete;
         PropertyWatchOfType& operator=(PropertyWatchOfType&&) = default;
         ~PropertyWatchOfType() = default;
-        explicit PropertyWatchOfType(
+        PropertyWatchOfType(
+            const PropertyIndex& watchIndex, Callback& callback) :
+            PropertyWatch<DBusInterfaceType>(watchIndex, &callback) {}
+        PropertyWatchOfType(
             const PropertyIndex& watchIndex) :
-            PropertyWatch<DBusInterfaceType>(watchIndex) {}
+            PropertyWatch<DBusInterfaceType>(watchIndex, nullptr) {}
+
 
         /** @brief PropertyMatch implementation for PropertyWatchOfType.
          *