commit 09c981700d7bd98eed54a670e959a424585dcd84
author Richard Marian Thomaiyar <richard.marian.thomaiyar@linux.intel.com> Thu Nov 15 23:32:21 2018 +0530
committer Richard Marian Thomaiyar <richard.marian.thomaiyar@linux.intel.com> Sat Dec 15 05:29:55 2018 +0000
tree 987d96f5d2b272c201fab9b617676db861da704e
parent 6ee43dc57bce75b36f0145c5e895d3811d5c47d4

update asio set property to signal properly

Set property has to send out signal only when there is
change in the property and skipped when there is no change
but still must return true for the set method accordingly

Unit test:
Using busctl monitor match rule, monitored the properties changed
of sensors (which uses asio logic) and verified by updating
the value with same & different one, and observed both the return
(success) and the properties changed signal generated only when
there is changed in the property value as expected.

Change-Id: I79be5b29f496109c19e415cdcfff89af76693de5
Signed-off-by: Richard Marian Thomaiyar <richard.marian.thomaiyar@linux.intel.com>

sdbusplus/asio/object_server.hpp

diff --git a/sdbusplus/asio/object_server.hpp b/sdbusplus/asio/object_server.hpp
index 347d1cc..5e367c8 100644
--- a/sdbusplus/asio/object_server.hpp
+++ b/sdbusplus/asio/object_server.hpp
@@ -31,11 +31,19 @@
   public:
     virtual int call(message::message& m) = 0;
 };
+
+enum class SetPropertyReturnValue : size_t
+{
+    fail = 0,
+    valueUpdated,
+    sameValueUpdated,
+};
+
 class callback_set
 {
   public:
-    virtual int call(message::message& m) = 0;
-    virtual int set(const boost::any& value) = 0;
+    virtual SetPropertyReturnValue call(message::message& m) = 0;
+    virtual SetPropertyReturnValue set(const boost::any& value) = 0;
 };
 
 template <typename T>
@@ -288,16 +296,34 @@
         func_(std::move(func))
     {
     }
-    int call(message::message& m) override
+    SetPropertyReturnValue call(message::message& m) override
     {
         PropertyType input;
         m.read(input);
 
-        return func_(input, *value_);
+        auto oldValue = *value_;
+        if (func_(input, *value_))
+        {
+            if (oldValue == *value_)
+            {
+                return SetPropertyReturnValue::sameValueUpdated;
+            }
+            return SetPropertyReturnValue::valueUpdated;
+        }
+        return SetPropertyReturnValue::fail;
     }
-    int set(const boost::any& value)
+    SetPropertyReturnValue set(const boost::any& value)
     {
-        return func_(boost::any_cast<PropertyType>(value), *value_);
+        auto oldValue = *value_;
+        if (func_(boost::any_cast<PropertyType>(value), *value_))
+        {
+            if (oldValue == *value_)
+            {
+                return SetPropertyReturnValue::sameValueUpdated;
+            }
+            return SetPropertyReturnValue::valueUpdated;
+        }
+        return SetPropertyReturnValue::fail;
     }
 
   private:
@@ -356,10 +382,6 @@
             PropertyType,
             std::function<int(const PropertyType&, PropertyType&)>>>(
             propertyPtr, [](const PropertyType& req, PropertyType& old) {
-                if (old == req)
-                {
-                    return 0;
-                }
                 old = req;
                 return 1;
             });
@@ -463,12 +485,16 @@
         auto func = callbacksSet_.find(name);
         if (func != callbacksSet_.end())
         {
-            if (func->second->set(value) != 1)
+            SetPropertyReturnValue status = func->second->set(value);
+            if ((status == SetPropertyReturnValue::valueUpdated) ||
+                (status == SetPropertyReturnValue::sameValueUpdated))
             {
-                return false;
+                if (status != SetPropertyReturnValue::sameValueUpdated)
+                {
+                    signal_property(name);
+                }
+                return true;
             }
-            signal_property(name);
-            return true;
         }
         return false;
     }
@@ -588,12 +614,17 @@
             try
             {
 #endif
-                int status = func->second->call(mesg);
-                if (status == 1)
+                SetPropertyReturnValue status = func->second->call(mesg);
+                if ((status == SetPropertyReturnValue::valueUpdated) ||
+                    (status == SetPropertyReturnValue::sameValueUpdated))
                 {
-                    data->signal_property(property);
-                    return status;
+                    if (status != SetPropertyReturnValue::sameValueUpdated)
+                    {
+                        data->signal_property(property);
+                    }
+                    return true;
                 }
+                return false;
 #ifdef __EXCEPTIONS
             }