protected override object VisitScopeCache(ServiceCallSite singletonCallSite, RuntimeResolverContext context)
{
// Check if we are in the situation where scoped service was promoted to singleton
// and we need to lock the root
RuntimeResolverLock requiredScope = context.Scope == context.Scope.Engine.Root ?
RuntimeResolverLock.Root :
RuntimeResolverLock.Scope;
return(VisitCache(singletonCallSite, context, context.Scope, requiredScope));
}
private object VisitCache(ServiceCallSite scopedCallSite, RuntimeResolverContext context, ServiceProviderEngineScope serviceProviderEngine, RuntimeResolverLock lockType)
{
bool lockTaken = false;
var resolvedServices = serviceProviderEngine.ResolvedServices;
// Taking locks only once allows us to fork resolution process
// on another thread without causing the deadlock because we
// always know that we are going to wait the other thread to finish before
// releasing the lock
if ((context.AcquiredLocks & lockType) == 0)
{
Monitor.Enter(resolvedServices, ref lockTaken);
}
try
{
if (!resolvedServices.TryGetValue(scopedCallSite.Cache.Key, out var resolved))
{
resolved = VisitCallSiteMain(scopedCallSite, new RuntimeResolverContext
{
Scope = serviceProviderEngine,
AcquiredLocks = context.AcquiredLocks | lockType
});
serviceProviderEngine.CaptureDisposable(resolved);
resolvedServices.Add(scopedCallSite.Cache.Key, resolved);
}
return(resolved);
}
finally
{
if (lockTaken)
{
Monitor.Exit(resolvedServices);
}
}
}
private object VisitCache(ServiceCallSite callSite, RuntimeResolverContext context, ServiceProviderEngineScope serviceProviderEngine, RuntimeResolverLock lockType)
{
bool lockTaken = false;
Dictionary <ServiceCacheKey, object> resolvedServices = serviceProviderEngine.ResolvedServices;
// Taking locks only once allows us to fork resolution process
// on another thread without causing the deadlock because we
// always know that we are going to wait the other thread to finish before
// releasing the lock
if ((context.AcquiredLocks & lockType) == 0)
{
Monitor.Enter(resolvedServices, ref lockTaken);
}
try
{
return(ResolveService(callSite, context, lockType, serviceProviderEngine));
}
finally
{
if (lockTaken)
{
Monitor.Exit(resolvedServices);
}
}
}
private object ResolveService(ServiceCallSite callSite, RuntimeResolverContext context, RuntimeResolverLock lockType, ServiceProviderEngineScope serviceProviderEngine)
{
Dictionary <ServiceCacheKey, object> resolvedServices = serviceProviderEngine.ResolvedServices;
if (!resolvedServices.TryGetValue(callSite.Cache.Key, out object resolved))
{
resolved = VisitCallSiteMain(callSite, new RuntimeResolverContext
{
Scope = serviceProviderEngine,
AcquiredLocks = context.AcquiredLocks | lockType
});
serviceProviderEngine.CaptureDisposable(resolved);
resolvedServices.Add(callSite.Cache.Key, resolved);
}
return(resolved);
}
private object VisitCache(ServiceCallSite callSite, RuntimeResolverContext context, ServiceProviderEngineScope serviceProviderEngine, RuntimeResolverLock lockType)
{
bool lockTaken = false;
object sync = serviceProviderEngine.Sync;
Dictionary <ServiceCacheKey, object> resolvedServices = serviceProviderEngine.ResolvedServices;
// Taking locks only once allows us to fork resolution process
// on another thread without causing the deadlock because we
// always know that we are going to wait the other thread to finish before
// releasing the lock
if ((context.AcquiredLocks & lockType) == 0)
{
Monitor.Enter(sync, ref lockTaken);
}
try
{
// Note: This method has already taken lock by the caller for resolution and access synchronization.
// For scoped: takes a dictionary as both a resolution lock and a dictionary access lock.
if (resolvedServices.TryGetValue(callSite.Cache.Key, out object resolved))
{
return(resolved);
}
resolved = VisitCallSiteMain(callSite, new RuntimeResolverContext
{
Scope = serviceProviderEngine,
AcquiredLocks = context.AcquiredLocks | lockType
});
serviceProviderEngine.CaptureDisposable(resolved);
resolvedServices.Add(callSite.Cache.Key, resolved);
return(resolved);
}
finally
{
if (lockTaken)
{
Monitor.Exit(sync);
}
}
}
private object ResolveService(ServiceCallSite callSite, RuntimeResolverContext context, RuntimeResolverLock lockType, ServiceProviderEngineScope serviceProviderEngine)
{
IDictionary <ServiceCacheKey, object> resolvedServices = serviceProviderEngine.ResolvedServices;
// Note: This method has already taken lock by the caller for resolution and access synchronization.
// For root: uses a concurrent dictionary and takes a per singleton lock for resolution.
// For scoped: takes a dictionary as both a resolution lock and a dictionary access lock.
Debug.Assert(
(lockType == RuntimeResolverLock.Root && resolvedServices is ConcurrentDictionary <ServiceCacheKey, object>) ||
(lockType == RuntimeResolverLock.Scope && Monitor.IsEntered(resolvedServices)));
if (resolvedServices.TryGetValue(callSite.Cache.Key, out object resolved))
{
return(resolved);
}
resolved = VisitCallSiteMain(callSite, new RuntimeResolverContext
{
Scope = serviceProviderEngine,
AcquiredLocks = context.AcquiredLocks | lockType
});
serviceProviderEngine.CaptureDisposable(resolved);
resolvedServices.Add(callSite.Cache.Key, resolved);
return(resolved);
}