Suppress unnecessary "failed alias" warnings

[simgear.git] / simgear / props / props.cxx

diff --git a/simgear/props/props.cxx b/simgear/props/props.cxx
index 499d417fb06009ad0f8e6e42dadd9d0d92ff4b7b..d690cbe66a55f00d246b863b742c3ccf2a9dad6c 100644 (file)
--- a/simgear/props/props.cxx
+++ b/simgear/props/props.cxx
@@ -11,6 +11,7 @@
 #endif
 
 #include "props.hxx"
+#include "vectorPropTemplates.hxx"
 
 #include <algorithm>
 
@@ -27,8 +28,6 @@
 #include <boost/functional/hash.hpp>
 #include <boost/range.hpp>
 
-#include <simgear/math/SGMath.hxx>
-
 #if PROPS_STANDALONE
 #include <iostream>
 #else
@@ -664,7 +663,8 @@ SGPropertyNode::SGPropertyNode ()
  * Copy constructor.
  */
 SGPropertyNode::SGPropertyNode (const SGPropertyNode &node)
-  : _index(node._index),
+  : SGReferenced(node),
+    _index(node._index),
     _name(node._name),
     _parent(0),                        // don't copy the parent
     _type(node._type),
@@ -777,13 +777,41 @@ SGPropertyNode::~SGPropertyNode ()
 bool
 SGPropertyNode::alias (SGPropertyNode * target)
 {
-  if (target == 0 || _type == props::ALIAS || _tied)
-    return false;
-  clearValue();
-  get(target);
-  _value.alias = target;
-  _type = props::ALIAS;
-  return true;
+  if (target && (_type != props::ALIAS) && (!_tied))
+  {
+    clearValue();
+    get(target);
+    _value.alias = target;
+    _type = props::ALIAS;
+    return true;
+  }
+
+#if PROPS_STANDALONE
+#else
+  if (!target)
+  {
+    SG_LOG(SG_GENERAL, SG_ALERT,
+           "Failed to create alias for " << getPath() << ". "
+           "The target property does not exist.");
+  }
+  else
+  if (_type == props::ALIAS)
+  {
+    if (_value.alias == target)
+        return true; // ok, identical alias requested
+    SG_LOG(SG_GENERAL, SG_ALERT,
+           "Failed to create alias at " << target->getPath() << ". "
+           "Source "<< getPath() << " is already aliasing another property.");
+  }
+  else
+  if (_tied)
+  {
+    SG_LOG(SG_GENERAL, SG_ALERT, "Failed to create alias at " << target->getPath() << ". "
+           "Source " << getPath() << " is a tied property.");
+  }
+#endif
+
+  return false;
 }