The .NET CLR Hosting API allows a native application to host and control the .NET Common Language Runtime (CLR). This enables: 1. Customizing the CLR's runtime behavior through policies, assembly loading, memory management, and more. 2. Monitoring and debugging CLR applications through profiling and debugging APIs. 3. Integrating the CLR into native applications and environments like device drivers through a hosting interface.

1. .NET CLR Hosting API
Evgen Napryaglo
Intetics

2. 1. Runtime Customizations
Runtime
Assembly
Loading
Policy
Management
Host
Protection
Memory
Management
Garbage
Collection
I/O
Completion
CLR
Events
Task
Management
Synchronization
Management
Thread Pool
Management
Application Host – Native Environment
.NET Application Environment

3. Objectives
• Monitoring
• Diagnostics
• Customization
• Restriction
• Integration
• Extensibility
Development Operations
Product Development
Enterprise Integration

4. 2. Execution & State Monitoring
Profiling
API
Debugging
API

5. CLR Hosting
Host
Runtime
.NET Codemscoree
ICLRRuntimeHost
CorBindToRuntimeEx
ICLRControlIHostControl
Assembly

6. Initialization Flow
:Host :mscoree :Runtime
CorBindToRuntimeEx
ICLRRuntimeHost
SetHostControl
Start
Initialization
ICLRControl
Status
GetCLRControl
ICLRControl
ExecuteInDefaultAppDomain

7. Assembly Loading
ICLRAssemblyReferenceList
ICLRAssemblyIdentityManager
• The location from which assemblies are loaded
• The way versions are managed
• The formats from which assemblies can be loaded
Customize
IHostAssemblyManager
IHostAssemblyStore

8. Synchronization Management
IHostSyncManager ICLRSyncManager
Enables the host to implement its own synchronization primitives for
the runtime to use.
Custom
Events IHostManualEvent, IHostAutoEvent
Critical Section
Semaphore IHostSemaphore
IHostCrst

9. Policy Management
ICLRPolicyManager IHostPolicyManager
Enables the host to specify the way program failures are handled, to
support different reliability requirements.
NoAction
ThrowException
AbortThread
RudeAbortThread
UnloadAppDomain
RudeUnloadAppDomain
ExitProcess
FastExitProcess
RudeExitProcess
DisableRuntime
NonCriticalResource
CriticalResource
FatalRuntime
OrphanedLock
StackOverflow
ThreadAbort
ThreadRudeAbortInNonCriticalRegion
ThreadRudeAbortInCriticalRegion
AppDomainUnload
AppDomainRudeUnload
ProcessExit
FinalizerRun
ActionsFailures
Events

10. Host Protection
Enables the host to enforce its own programming model, by
preventing the use of specified types or members.
ICLRHostProtectionManager
Reflection
Licensing
Synchronization
UI Components

11. Thread Pool Management
Enables the host to implement its own thread pool for the runtime
to use.
IHostThreadPoolManager
GetAvailableThreads
GetMaxThreads
GetMinThreads
QueueUserWorkItem
SetMaxThreads
SetMinThreads

12. I/O Completion
IHostIoCompletionManager
Enables the host to implement its own implementation of
asynchronous input/output.
ICLRIoCompletionManager
CLR
Host
IHostIoCompletionManager
ICLRIoCompletionManager
IO Operations Calls
Results & Feedback

13. Profiling
• Class loading and unloading
events.
• Thread creation and destruction
events.
• Function entry and exit events.
• Exceptions.
• Transitions between different
runtime contexts.
• Information about runtime
suspensions.
• Information about the runtime
memory heap and garbage
collection activity.
Application
For
Profiling
CLR
HOST IPC Transport
Profiler
User
Interface
Profile Target Profiler
ICorProfilerInfo
ICorProfilerCallback

14. Debugging
Application
For
Debugging
CLR
HOST IPC Transport
Debugger
User
Interface
Profile Target Debugger
ICorDebug
ICorDebugManagedCallback
• Accessing Call Stacks and
Variables
• Accessing IL Code and Native
Code
• On-the-Fly Data and Code
modifications
• Runtime Expressions Evaluation
• IL Code Injections
• Custom Breakpoints
• Step by Step Execution

15. Practical Case

16. Architecture
Domestic Area

17. New Architecture
Printer
Domestic Area
Internet

18. Windows User Mode Driver Framework
Virtual Printer Driver
CLR Host
.NET Data
Converter
.NET Data
Converter
.NET Data
Converter
Native
Native
Native

19. CLR Hosting vs COM Integration
Simple Programming Model
Fully Managed
Good Performance
Flexible Programming Model
High Reliability
Tailored Integration with Native Services
Native Programming Environment
Low Reliability
COM Infrastructure Availability
Complex Diagnostics
Strange Errors

20. THANK YOU