private T LazyInitValue()
{
Boxed boxed;
switch (Mode)
{
case LazyThreadSafetyMode.None:
boxed = CreateValue();
m_Boxed = boxed;
break;
case LazyThreadSafetyMode.PublicationOnly:
boxed = CreateValue();
object mBoxed = m_Boxed;
if (Interlocked.CompareExchange(ref mBoxed, boxed, null) != null)
{
boxed = (Boxed)m_Boxed;
}
break;
default:
{
object obj2;
bool lockTaken = Monitor.TryEnter(obj2 = m_ThreadSafeObj);
try
{
if (m_Boxed == null)
{
boxed = CreateValue();
m_Boxed = boxed;
}
else
{
boxed = m_Boxed as Boxed;
if (boxed == null)
{
LazyInternalExceptionHolder holder = (LazyInternalExceptionHolder)m_Boxed;
throw holder.Exception;
}
}
}
finally
{
if (lockTaken)
{
Monitor.Exit(obj2);
}
}
break;
}
}
return(boxed.Value);
}
public async Task <T> FetchValueAsync()
{
Boxed boxed = null;
if (this.boxed != null)
{
// Do a quick check up front for the fast path.
boxed = this.boxed as Boxed;
if (boxed != null)
{
return(boxed.value);
}
LazyInternalExceptionHolder exc = this.boxed as LazyInternalExceptionHolder;
exc.m_edi.Throw();
}
return(await LazyInitValue());
}
private bool TryGetValueOrThrowException(out T value)
{
Boxed boxed = m_value as Boxed;
if (boxed != null)
{
value = boxed.Value;
return(true);
}
LazyInternalExceptionHolder exHolder = m_value as LazyInternalExceptionHolder;
exHolder?.ExceptionInfo.Throw();
value = default(T);
return(false);
}
/// <summary>
/// local helper method to initialize the value
/// </summary>
/// <returns>The inititialized T value</returns>
private TResult LazyInitValue()
{
Boxed boxed = null;
object threadSafeObj = Volatile.Read(ref m_threadSafeObj);
bool lockTaken = false;
try
{
if (threadSafeObj != (object)ALREADY_INVOKED_SENTINEL)
{
Monitor.Enter(threadSafeObj, ref lockTaken);
}
else
{
Contract.Assert(m_boxed != null);
}
if (m_boxed == null)
{
boxed = CreateValue();
m_boxed = boxed;
Volatile.Write(ref m_threadSafeObj, ALREADY_INVOKED_SENTINEL);
}
else // got the lock but the value is not null anymore, check if it is created by another thread or faulted and throw if so
{
boxed = m_boxed as Boxed;
if (boxed == null) // it is not Boxed, so it is a LazyInternalExceptionHolder
{
LazyInternalExceptionHolder exHolder = m_boxed as LazyInternalExceptionHolder;
Contract.Assert(exHolder != null);
exHolder.m_edi.Throw();
}
}
}
finally
{
if (lockTaken)
{
Monitor.Exit(threadSafeObj);
}
}
Contract.Assert(boxed != null);
return(boxed.m_value);
}
/// <summary>
/// local helper method to initialize the value
/// </summary>
/// <returns>The inititialized T value</returns>
private T LazyInitValue()
{
Boxed boxed = null;
LazyThreadSafetyMode mode = Mode;
if (mode == LazyThreadSafetyMode.None)
{
boxed = CreateValue();
m_boxed = boxed;
}
else if (mode == LazyThreadSafetyMode.PublicationOnly)
{
boxed = CreateValue();
if (Interlocked.CompareExchange(ref m_boxed, boxed, null) != null)
{
boxed = (Boxed)m_boxed; // set the boxed value to the succeeded thread value
}
}
else
{
lock (m_threadSafeObj)
{
if (m_boxed == null)
{
boxed = CreateValue();
m_boxed = boxed;
}
else // got the lock but the value is not null anymore, check if it is created by another thread or faulted and throw if so
{
boxed = m_boxed as Boxed;
if (boxed == null) // it is not Boxed, so it is a LazyInternalExceptionHolder
{
LazyInternalExceptionHolder exHolder = m_boxed as LazyInternalExceptionHolder;
Contract.Assert(exHolder != null);
throw exHolder.m_exception;
}
}
}
}
Contract.Assert(boxed != null);
return(boxed.m_value);
}
private T LazyInitValue()
{
Boxed <T> boxed = null;
switch (this.Mode)
{
case LazyThreadSafetyMode.None:
boxed = this.CreateValue();
this.m_boxed = boxed;
break;
case LazyThreadSafetyMode.PublicationOnly:
boxed = this.CreateValue();
if (Interlocked.CompareExchange(ref this.m_boxed, boxed, null) != null)
{
boxed = (Boxed <T>) this.m_boxed;
}
break;
default:
lock (this.m_threadSafeObj)
{
if (this.m_boxed == null)
{
boxed = this.CreateValue();
this.m_boxed = boxed;
}
else
{
boxed = this.m_boxed as Boxed <T>;
if (boxed == null)
{
LazyInternalExceptionHolder <T> holder = this.m_boxed as LazyInternalExceptionHolder <T>;
throw holder.m_exception;
}
}
}
break;
}
return(boxed.m_value);
}
/// <summary>
/// local helper method to initialize the value
/// </summary>
/// <returns>The inititialized T value</returns>
private T LazyInitValue()
{
Boxed boxed = null;
LazyThreadSafetyMode mode = Mode;
if (m_boxed == null)
{
boxed = CreateValue();
m_boxed = boxed;
}
else // got the lock but the value is not null anymore, check if it is created by another thread or faulted and throw if so
{
boxed = m_boxed as Boxed;
if (boxed == null) // it is not Boxed, so it is a LazyInternalExceptionHolder
{
LazyInternalExceptionHolder exHolder = m_boxed as LazyInternalExceptionHolder;
System.Diagnostics.Debug.Assert(exHolder != null);
throw exHolder.m_exception;
}
}
System.Diagnostics.Debug.Assert(boxed != null);
return(boxed.m_value);
}
/// <summary>
/// local helper method to initialize the value
/// </summary>
/// <returns>The inititialized T value</returns>
private T LazyInitValue()
{
Boxed boxed = null;
LazyThreadSafetyMode mode = Mode;
if (mode == LazyThreadSafetyMode.None)
{
boxed = CreateValue();
m_boxed = boxed;
}
else if (mode == LazyThreadSafetyMode.PublicationOnly)
{
boxed = CreateValue();
if (boxed == null ||
Interlocked.CompareExchange(ref m_boxed, boxed, null) != null)
{
// If CreateValue returns null, it means another thread successfully invoked the value factory
// and stored the result, so we should just take what was stored. If CreateValue returns non-null
// but another thread set the value we should just take what was stored.
boxed = (Boxed)m_boxed;
}
else
{
// We successfully created and stored the value. At this point, the value factory delegate is
// no longer needed, and we don't want to hold onto its resources.
m_valueFactory = ALREADY_INVOKED_SENTINEL;
}
}
else
{
object threadSafeObj = m_threadSafeObj;
bool lockTaken = false;
try
{
if (threadSafeObj != (object)ALREADY_INVOKED_SENTINEL)
{
Monitor2.Enter(threadSafeObj, ref lockTaken);
}
else
{
Debug.Assert(m_boxed != null);
}
if (m_boxed == null)
{
boxed = CreateValue();
m_boxed = boxed;
m_threadSafeObj = ALREADY_INVOKED_SENTINEL;
}
else // got the lock but the value is not null anymore, check if it is created by another thread or faulted and throw if so
{
boxed = m_boxed as Boxed;
if (boxed == null) // it is not Boxed, so it is a LazyInternalExceptionHolder
{
LazyInternalExceptionHolder exHolder = m_boxed as LazyInternalExceptionHolder;
Debug.Assert(exHolder != null);
exHolder.m_edi.Throw();
}
}
}
finally
{
if (lockTaken)
{
Monitor.Exit(threadSafeObj);
}
}
}
Debug.Assert(boxed != null);
return(boxed.m_value);
}
/// <summary>
/// local helper method to initialize the value
/// </summary>
/// <returns>The inititialized T value</returns>
private async Task <T> LazyInitValue()
{
Boxed boxed = null;
LazyThreadSafetyMode mode = Mode;
if (mode == LazyThreadSafetyMode.None)
{
boxed = await CreateValue();
this.boxed = boxed;
}
else if (mode == LazyThreadSafetyMode.PublicationOnly)
{
boxed = await CreateValue();
if (boxed == null ||
Interlocked.CompareExchange(ref this.boxed, boxed, null) != null)
{
boxed = (Boxed)this.boxed;
}
else
{
valueFactory = alreadyInvokedSentinel;
}
}
else
{
object threadSafeObject = Volatile.Read(ref threadSafeObj);
bool lockTaken = false;
try
{
if (threadSafeObject != (object)alreadyInvokedSentinel)
{
Monitor.Enter(threadSafeObject, ref lockTaken);
}
else
{
Contract.Assert(this.boxed != null);
}
if (this.boxed == null)
{
boxed = await CreateValue();
this.boxed = boxed;
Volatile.Write(ref threadSafeObj, alreadyInvokedSentinel);
}
else
{
boxed = this.boxed as Boxed;
if (boxed == null) // it is not Boxed, so it is a LazyInternalExceptionHolder
{
LazyInternalExceptionHolder exHolder = this.boxed as LazyInternalExceptionHolder;
Contract.Assert(exHolder != null);
exHolder.m_edi.Throw();
}
}
}
finally
{
if (lockTaken)
{
Monitor.Exit(threadSafeObject);
}
}
}
Contract.Assert(boxed != null);
return(boxed.value);
}
