public List <KeyValuePair <string, string> > Morph(object args)
{
// Transform the args into a bag of key-value strings.
var outputArgs = new List <KeyValuePair <string, string> >();
if (args != null)
{
if (!_noImplicitTransforms)
{
// given the type, fetch the implicit transforms for that type and put it in the implicitTransforms variable.
Type argType = args.GetType();
TransformSpec implicitTransforms;
// First check the one-element cache _firstImplicitTransformsEntry
ImplicitTransformEntry cacheEntry = _firstImplicitTransformsEntry;
if (cacheEntry != null && cacheEntry.Type == argType)
{
implicitTransforms = cacheEntry.Transforms; // Yeah we hit the cache.
}
else if (cacheEntry == null)
{
// _firstImplicitTransformsEntry is empty, we should fill it.
// Note that it is OK that two threads may race and both call MakeImplicitTransforms on their own
// (that is we don't expect exactly once initialization of _firstImplicitTransformsEntry)
implicitTransforms = MakeImplicitTransforms(argType);
Interlocked.CompareExchange(ref _firstImplicitTransformsEntry,
new ImplicitTransformEntry()
{
Type = argType, Transforms = implicitTransforms
}, null);
}
else
{
// This should only happen when you are wildcarding your events (reasonably rare).
// In that case you will probably need many types
// Note currently we don't limit the cache size, but it is limited by the number of
// distinct types of objects passed to DiagnosticSource.Write.
if (_implicitTransformsTable == null)
{
Interlocked.CompareExchange(ref _implicitTransformsTable,
new ConcurrentDictionary <Type, TransformSpec>(1, 8), null);
}
implicitTransforms = _implicitTransformsTable.GetOrAdd(argType, type => MakeImplicitTransforms(type));
}
// implicitTransformas now fetched from cache or constructed, use it to Fetch all the implicit fields.
if (implicitTransforms != null)
{
for (TransformSpec serializableArg = implicitTransforms; serializableArg != null; serializableArg = serializableArg.Next)
{
outputArgs.Add(serializableArg.Morph(args));
}
}
}
if (_explicitTransforms != null)
{
for (var explicitTransform = _explicitTransforms; explicitTransform != null; explicitTransform = explicitTransform.Next)
{
var keyValue = explicitTransform.Morph(args);
if (keyValue.Value != null)
{
outputArgs.Add(keyValue);
}
}
}
}
return(outputArgs);
}
