private ContextCookie EnterContext(string path)
{
ContextCookie cookie = new ContextCookie(_rootInfo, EnterContext());
if (PSDriveInfo == null && !string.IsNullOrEmpty(path))
{
_rootInfo = ParsePSPathRoot(path);
}
return(cookie);
}
/// <summary>
/// Returns the existing RCW or create a new RCW from the COM interface pointer
/// NOTE: Don't use this overload if you already have the identity IUnknown
/// </summary>
/// <param name="expectedContext">
/// The current context of this thread. If it is passed and is not Default, we'll check whether the
/// returned RCW from cache matches this expected context. If it is not a match (from a different
/// context, and is not free threaded), we'll go ahead ignoring the cached entry, and create a new
/// RCW instead - which will always end up in the current context
/// We'll skip the check if current == ContextCookie.Default.
/// </param>
internal static object ComInterfaceToComObject(
IntPtr pComItf,
RuntimeTypeHandle interfaceType,
RuntimeTypeHandle classTypeInSigature,
ContextCookie expectedContext,
CreateComObjectFlags flags
)
{
Debug.Assert(expectedContext.IsDefault || expectedContext.IsCurrent);
//
// Get identity IUnknown for lookup
//
IntPtr pComIdentityIUnknown = McgMarshal.ComQueryInterfaceNoThrow(pComItf, ref Interop.COM.IID_IUnknown);
if (pComIdentityIUnknown == default(IntPtr))
{
throw new InvalidCastException();
}
try
{
object obj = ComInterfaceToComObjectInternal(
pComItf,
pComIdentityIUnknown,
interfaceType,
classTypeInSigature,
expectedContext,
flags
);
return(obj);
}
finally
{
McgMarshal.ComRelease(pComIdentityIUnknown);
}
}
/// <summary>
/// Returns the existing RCW or create a new RCW from the COM interface pointer
/// NOTE: This does not do any unboxing at all.
/// </summary>
/// <param name="expectedContext">
/// The current context of this thread. If it is passed and is not Default, we'll check whether the
/// returned RCW from cache matches this expected context. If it is not a match (from a different
/// context, and is not free threaded), we'll go ahead ignoring the cached entry, and create a new
/// RCW instead - which will always end up in the current context
/// We'll skip the check if current == ContextCookie.Default.
/// </param>
private static object ComInterfaceToComObjectInternal_NoCache(
IntPtr pComItf,
IntPtr pComIdentityIUnknown,
RuntimeTypeHandle interfaceType,
RuntimeTypeHandle classTypeInSignature,
ContextCookie expectedContext,
CreateComObjectFlags flags,
out string className
)
{
className = null;
//
// Lookup RCW in global RCW cache based on the identity IUnknown
//
__ComObject comObject = ComObjectCache.Lookup(pComIdentityIUnknown);
if (comObject != null)
{
bool useThisComObject = true;
if (!expectedContext.IsDefault)
{
//
// Make sure the returned RCW matches the context we specify (if any)
//
if (!comObject.IsFreeThreaded &&
!comObject.ContextCookie.Equals(expectedContext))
{
//
// This is a mismatch.
// We only care about context for WinRT factory RCWs (which is the only place we are
// passing in the context right now).
// When we get back a WinRT factory RCW created in a different context. This means the
// factory is a singleton, and the returned IActivationFactory could be either one of
// the following:
// 1) A raw pointer, and it acts like a free threaded object
// 2) A proxy that is used across different contexts. It might maintain a list of contexts
// that it is marshaled to, and will fail to be called if it is not marshaled to this
// context yet.
//
// In this case, it is unsafe to use this RCW in this context and we should proceed
// to create a duplicated one instead. It might make sense to have a context-sensitive
// RCW cache but I don't think this case will be common enough to justify it
//
// @TODO: Check for DCOM proxy as well
useThisComObject = false;
}
}
if (useThisComObject)
{
//
// We found one - AddRef and return
//
comObject.AddRef();
return comObject;
}
}
string winrtClassName = null;
bool isSealed = false;
if (!classTypeInSignature.IsNull())
{
isSealed = classTypeInSignature.IsSealed();
}
//
// Only look at runtime class name if the class type in signature is not sealed
// NOTE: In the case of System.Uri, we are not pass the class type, only the interface
//
if (!isSealed &&
(flags & CreateComObjectFlags.SkipTypeResolutionAndUnboxing) == 0)
{
IntPtr pInspectable;
bool needRelease = false;
if (interfaceType.IsSupportIInspectable())
{
//
// Use the interface pointer as IInspectable as we know it is indeed a WinRT interface that
// derives from IInspectable
//
pInspectable = pComItf;
}
else if ((flags & CreateComObjectFlags.IsWinRTObject) != 0)
{
//
// Otherwise, if someone tells us that this is a WinRT object, but we don't have a
// IInspectable interface at hand, we'll QI for it
//
pInspectable = McgMarshal.ComQueryInterfaceNoThrow(pComItf, ref Interop.COM.IID_IInspectable);
needRelease = true;
}
else
{
pInspectable = default(IntPtr);
}
try
{
if (pInspectable != default(IntPtr))
{
className = McgComHelpers.GetRuntimeClassName(pInspectable);
winrtClassName = className;
}
}
finally
{
if (needRelease && pInspectable != default(IntPtr))
{
McgMarshal.ComRelease(pInspectable);
pInspectable = default(IntPtr);
}
}
}
//
// 1. Prefer using the class returned from GetRuntimeClassName
// 2. Otherwise use the class (if there) in the signature
// 3. Out of options - create __ComObject
//
RuntimeTypeHandle classTypeToCreateRCW = default(RuntimeTypeHandle);
RuntimeTypeHandle interfaceTypeFromName = default(RuntimeTypeHandle);
if (!String.IsNullOrEmpty(className))
{
if (!McgModuleManager.TryGetClassTypeFromName(className, out classTypeToCreateRCW))
{
//
// If we can't find the class name in our map, try interface as well
// Such as IVector<Int32>
// This apparently won't work if we haven't seen the interface type in MCG
//
McgModuleManager.TryGetInterfaceTypeFromName(className, out interfaceTypeFromName);
}
}
if (classTypeToCreateRCW.IsNull())
classTypeToCreateRCW = classTypeInSignature;
// Use identity IUnknown to create the new RCW
// @TODO: Transfer the ownership of ref count to the RCW
if (classTypeToCreateRCW.IsNull())
{
//
// Create a weakly typed RCW because we have no information about this particular RCW
// @TODO - what if this RCW is not seen by MCG but actually exists in WinMD and therefore we
// are missing GCPressure and ComMarshallingType information for this object?
//
comObject = new __ComObject(pComIdentityIUnknown, default(RuntimeTypeHandle));
}
else
{
//
// Create a strongly typed RCW based on RuntimeTypeHandle
//
comObject = CreateComObjectInternal(classTypeToCreateRCW, pComIdentityIUnknown); // Use identity IUnknown to create the new RCW
}
#if DEBUG
//
// Remember the runtime class name for debugging purpose
// This way you can tell what the class name is, even when we failed to create a strongly typed
// RCW for it
//
comObject.m_runtimeClassName = className;
#endif
//
// Make sure we QI for that interface
//
if (!interfaceType.IsNull())
{
comObject.QueryInterface_NoAddRef_Internal(interfaceType, /* cacheOnly= */ false, /* throwOnQueryInterfaceFailure= */ false);
}
return comObject;
}
/// <summary>
/// Returns the existing RCW or create a new RCW from the COM interface pointer
/// NOTE: This does unboxing unless CreateComObjectFlags.SkipTypeResolutionAndUnboxing is specified
/// </summary>
/// <param name="expectedContext">
/// The current context of this thread. If it is passed and is not Default, we'll check whether the
/// returned RCW from cache matches this expected context. If it is not a match (from a different
/// context, and is not free threaded), we'll go ahead ignoring the cached entry, and create a new
/// RCW instead - which will always end up in the current context
/// We'll skip the check if current == ContextCookie.Default.
/// </param>
internal static object ComInterfaceToComObjectInternal(
IntPtr pComItf,
IntPtr pComIdentityIUnknown,
RuntimeTypeHandle interfaceType,
RuntimeTypeHandle classTypeInSignature,
ContextCookie expectedContext,
CreateComObjectFlags flags
)
{
string className;
object obj = ComInterfaceToComObjectInternal_NoCache(
pComItf,
pComIdentityIUnknown,
interfaceType,
classTypeInSignature,
expectedContext,
flags,
out className
);
//
// The assumption here is that if the classInfoInSignature is null and interfaceTypeInfo
// is either IUnknow and IInspectable we need to try unboxing.
//
bool doUnboxingCheck =
(flags & CreateComObjectFlags.SkipTypeResolutionAndUnboxing) == 0 &&
obj != null &&
classTypeInSignature.IsNull() &&
(interfaceType.Equals(InternalTypes.IUnknown) ||
interfaceType.IsIInspectable());
if (doUnboxingCheck)
{
//
// Try unboxing
// Even though this might just be a IUnknown * from the signature, we still attempt to unbox
// if it implements IInspectable
//
// @TODO - We might need to optimize this by pre-checking the names to see if they
// potentially represents a boxed type, but for now let's keep it simple and I also don't
// want to replicate the knowledge here
// @TODO2- We probably should skip the creating the COM object in the first place.
//
// NOTE: the RCW here could be a cached one (for a brief time if GC doesn't kick in. as there
// is nothing to hold the RCW alive for IReference<T> RCWs), so this could save us a RCW
// creation cost potentially. Desktop CLR doesn't do this. But we also paying for unnecessary
// cache management cost, and it is difficult to say which way is better without proper
// measuring
//
object unboxedObj = McgMarshal.UnboxIfBoxed(obj, className);
if (unboxedObj != null)
return unboxedObj;
}
//
// In order for variance to work, we save the incoming interface pointer as specified in the
// signature into the cache, so that we know this RCW does support this interface and variance
// can take advantage of that later
// NOTE: In some cases, native might pass a WinRT object as a 'compatible' interface, for example,
// pass IVector<IFoo> as IVector<Object> because they are 'compatible', but QI for IVector<object>
// won't succeed. In this case, we'll just believe it implements IVector<Object> as in the
// signature while the underlying interface pointer is actually IVector<IFoo>
//
__ComObject comObject = obj as __ComObject;
if (comObject != null)
{
McgMarshal.ComAddRef(pComItf);
try
{
comObject.InsertIntoCache(interfaceType, ContextCookie.Current, ref pComItf, true);
}
finally
{
//
// Only release when a exception is thrown or we didn't 'swallow' the ref count by
// inserting it into the cache
//
McgMarshal.ComSafeRelease(pComItf);
}
}
return obj;
}
/// <summary>
/// Returns the existing RCW or create a new RCW from the COM interface pointer
/// NOTE: Don't use this overload if you already have the identity IUnknown
/// </summary>
/// <param name="expectedContext">
/// The current context of this thread. If it is passed and is not Default, we'll check whether the
/// returned RCW from cache matches this expected context. If it is not a match (from a different
/// context, and is not free threaded), we'll go ahead ignoring the cached entry, and create a new
/// RCW instead - which will always end up in the current context
/// We'll skip the check if current == ContextCookie.Default.
/// </param>
internal static object ComInterfaceToComObject(
IntPtr pComItf,
RuntimeTypeHandle interfaceType,
RuntimeTypeHandle classTypeInSigature,
ContextCookie expectedContext,
CreateComObjectFlags flags
)
{
Debug.Assert(expectedContext.IsDefault || expectedContext.IsCurrent);
//
// Get identity IUnknown for lookup
//
IntPtr pComIdentityIUnknown = McgMarshal.ComQueryInterfaceNoThrow(pComItf, ref Interop.COM.IID_IUnknown);
if (pComIdentityIUnknown == default(IntPtr))
throw new InvalidCastException();
try
{
object obj = ComInterfaceToComObjectInternal(
pComItf,
pComIdentityIUnknown,
interfaceType,
classTypeInSigature,
expectedContext,
flags
);
return obj;
}
finally
{
McgMarshal.ComRelease(pComIdentityIUnknown);
}
}
private ContextCookie EnterContext(string path)
{
ContextCookie cookie = new ContextCookie(_rootInfo, EnterContext());
if (PSDriveInfo == null && !string.IsNullOrEmpty(path))
{
_rootInfo = ParsePSPathRoot(path);
}
return cookie;
}
/// <summary>
/// Returns the existing RCW or create a new RCW from the COM interface pointer
/// NOTE: This does not do any unboxing at all.
/// </summary>
/// <param name="expectedContext">
/// The current context of this thread. If it is passed and is not Default, we'll check whether the
/// returned RCW from cache matches this expected context. If it is not a match (from a different
/// context, and is not free threaded), we'll go ahead ignoring the cached entry, and create a new
/// RCW instead - which will always end up in the current context
/// We'll skip the check if current == ContextCookie.Default.
/// </param>
private static object ComInterfaceToComObjectInternal_NoCache(
IntPtr pComItf,
IntPtr pComIdentityIUnknown,
RuntimeTypeHandle interfaceType,
RuntimeTypeHandle classTypeInSignature,
ContextCookie expectedContext,
CreateComObjectFlags flags,
out string className
)
{
className = null;
//
// Lookup RCW in global RCW cache based on the identity IUnknown
//
__ComObject comObject = ComObjectCache.Lookup(pComIdentityIUnknown);
if (comObject != null)
{
bool useThisComObject = true;
if (!expectedContext.IsDefault)
{
//
// Make sure the returned RCW matches the context we specify (if any)
//
if (!comObject.IsFreeThreaded &&
!comObject.ContextCookie.Equals(expectedContext))
{
//
// This is a mismatch.
// We only care about context for WinRT factory RCWs (which is the only place we are
// passing in the context right now).
// When we get back a WinRT factory RCW created in a different context. This means the
// factory is a singleton, and the returned IActivationFactory could be either one of
// the following:
// 1) A raw pointer, and it acts like a free threaded object
// 2) A proxy that is used across different contexts. It might maintain a list of contexts
// that it is marshaled to, and will fail to be called if it is not marshaled to this
// context yet.
//
// In this case, it is unsafe to use this RCW in this context and we should proceed
// to create a duplicated one instead. It might make sense to have a context-sensitive
// RCW cache but I don't think this case will be common enough to justify it
//
// @TODO: Check for DCOM proxy as well
useThisComObject = false;
}
}
if (useThisComObject)
{
//
// We found one - AddRef and return
//
comObject.AddRef();
return(comObject);
}
}
string winrtClassName = null;
bool isSealed = false;
if (!classTypeInSignature.IsNull())
{
isSealed = classTypeInSignature.IsSealed();
}
//
// Only look at runtime class name if the class type in signature is not sealed
// NOTE: In the case of System.Uri, we are not pass the class type, only the interface
//
if (!isSealed &&
(flags & CreateComObjectFlags.SkipTypeResolutionAndUnboxing) == 0)
{
IntPtr pInspectable;
bool needRelease = false;
if (interfaceType.IsSupportIInspectable())
{
//
// Use the interface pointer as IInspectable as we know it is indeed a WinRT interface that
// derives from IInspectable
//
pInspectable = pComItf;
}
else if ((flags & CreateComObjectFlags.IsWinRTObject) != 0)
{
//
// Otherwise, if someone tells us that this is a WinRT object, but we don't have a
// IInspectable interface at hand, we'll QI for it
//
pInspectable = McgMarshal.ComQueryInterfaceNoThrow(pComItf, ref Interop.COM.IID_IInspectable);
needRelease = true;
}
else
{
pInspectable = default(IntPtr);
}
try
{
if (pInspectable != default(IntPtr))
{
className = McgComHelpers.GetRuntimeClassName(pInspectable);
winrtClassName = className;
}
}
finally
{
if (needRelease && pInspectable != default(IntPtr))
{
McgMarshal.ComRelease(pInspectable);
pInspectable = default(IntPtr);
}
}
}
//
// 1. Prefer using the class returned from GetRuntimeClassName
// 2. Otherwise use the class (if there) in the signature
// 3. Out of options - create __ComObject
//
RuntimeTypeHandle classTypeToCreateRCW = default(RuntimeTypeHandle);
RuntimeTypeHandle interfaceTypeFromName = default(RuntimeTypeHandle);
if (!String.IsNullOrEmpty(className))
{
if (!McgModuleManager.TryGetClassTypeFromName(className, out classTypeToCreateRCW))
{
//
// If we can't find the class name in our map, try interface as well
// Such as IVector<Int32>
// This apparently won't work if we haven't seen the interface type in MCG
//
McgModuleManager.TryGetInterfaceTypeFromName(className, out interfaceTypeFromName);
}
}
if (classTypeToCreateRCW.IsNull())
{
classTypeToCreateRCW = classTypeInSignature;
}
// Use identity IUnknown to create the new RCW
// @TODO: Transfer the ownership of ref count to the RCW
if (classTypeToCreateRCW.IsNull())
{
//
// Create a weakly typed RCW because we have no information about this particular RCW
// @TODO - what if this RCW is not seen by MCG but actually exists in WinMD and therefore we
// are missing GCPressure and ComMarshallingType information for this object?
//
comObject = new __ComObject(pComIdentityIUnknown, default(RuntimeTypeHandle));
}
else
{
//
// Create a strongly typed RCW based on RuntimeTypeHandle
//
comObject = CreateComObjectInternal(classTypeToCreateRCW, pComIdentityIUnknown); // Use identity IUnknown to create the new RCW
}
#if DEBUG
//
// Remember the runtime class name for debugging purpose
// This way you can tell what the class name is, even when we failed to create a strongly typed
// RCW for it
//
comObject.m_runtimeClassName = className;
#endif
//
// Make sure we QI for that interface
//
if (!interfaceType.IsNull())
{
comObject.QueryInterface_NoAddRef_Internal(interfaceType, /* cacheOnly= */ false, /* throwOnQueryInterfaceFailure= */ false);
}
return(comObject);
}
/// <summary>
/// Returns the existing RCW or create a new RCW from the COM interface pointer
/// NOTE: This does unboxing unless CreateComObjectFlags.SkipTypeResolutionAndUnboxing is specified
/// </summary>
/// <param name="expectedContext">
/// The current context of this thread. If it is passed and is not Default, we'll check whether the
/// returned RCW from cache matches this expected context. If it is not a match (from a different
/// context, and is not free threaded), we'll go ahead ignoring the cached entry, and create a new
/// RCW instead - which will always end up in the current context
/// We'll skip the check if current == ContextCookie.Default.
/// </param>
internal static object ComInterfaceToComObjectInternal(
IntPtr pComItf,
IntPtr pComIdentityIUnknown,
RuntimeTypeHandle interfaceType,
RuntimeTypeHandle classTypeInSignature,
ContextCookie expectedContext,
CreateComObjectFlags flags
)
{
string className;
object obj = ComInterfaceToComObjectInternal_NoCache(
pComItf,
pComIdentityIUnknown,
interfaceType,
classTypeInSignature,
expectedContext,
flags,
out className
);
//
// The assumption here is that if the classInfoInSignature is null and interfaceTypeInfo
// is either IUnknow and IInspectable we need to try unboxing.
//
bool doUnboxingCheck =
(flags & CreateComObjectFlags.SkipTypeResolutionAndUnboxing) == 0 &&
obj != null &&
classTypeInSignature.IsNull() &&
(interfaceType.Equals(InternalTypes.IUnknown) ||
interfaceType.IsIInspectable());
if (doUnboxingCheck)
{
//
// Try unboxing
// Even though this might just be a IUnknown * from the signature, we still attempt to unbox
// if it implements IInspectable
//
// @TODO - We might need to optimize this by pre-checking the names to see if they
// potentially represents a boxed type, but for now let's keep it simple and I also don't
// want to replicate the knowledge here
// @TODO2- We probably should skip the creating the COM object in the first place.
//
// NOTE: the RCW here could be a cached one (for a brief time if GC doesn't kick in. as there
// is nothing to hold the RCW alive for IReference<T> RCWs), so this could save us a RCW
// creation cost potentially. Desktop CLR doesn't do this. But we also paying for unnecessary
// cache management cost, and it is difficult to say which way is better without proper
// measuring
//
object unboxedObj = McgMarshal.UnboxIfBoxed(obj, className);
if (unboxedObj != null)
{
return(unboxedObj);
}
}
//
// In order for variance to work, we save the incoming interface pointer as specified in the
// signature into the cache, so that we know this RCW does support this interface and variance
// can take advantage of that later
// NOTE: In some cases, native might pass a WinRT object as a 'compatible' interface, for example,
// pass IVector<IFoo> as IVector<Object> because they are 'compatible', but QI for IVector<object>
// won't succeed. In this case, we'll just believe it implements IVector<Object> as in the
// signature while the underlying interface pointer is actually IVector<IFoo>
//
__ComObject comObject = obj as __ComObject;
if (comObject != null)
{
McgMarshal.ComAddRef(pComItf);
try
{
comObject.InsertIntoCache(interfaceType, ContextCookie.Current, ref pComItf, true);
}
finally
{
//
// Only release when a exception is thrown or we didn't 'swallow' the ref count by
// inserting it into the cache
//
McgMarshal.ComSafeRelease(pComItf);
}
}
return(obj);
}
