/// <summary>
/// Acquires a lock in the context of this store transaction.
/// </summary>
/// <param name="lockManager">Lock manager that issues the lock.</param>
/// <param name="lockResourceNameHash">Lock resource name hash.</param>
/// <param name="lockMode">Lock mode requested.</param>
/// <param name="lockTimeout">Lock timeout.</param>
/// <exception cref="TransactionFaultedException" />
/// <exception cref="InvalidOperationException">Thrown by the replicator (ReplicatorTransactionBase.AddLockContext)</exception>
/// <exception cref="TimeoutException" />
/// <returns></returns>
public async Task <ILock> LockAsync(LockManager lockManager, ulong lockResourceNameHash, LockMode lockMode, int lockTimeout)
{
// Check arguments.
if (LockMode.Free == lockMode)
{
throw new ArgumentException(SR.Error_LockMode);
}
if (0 > lockTimeout && Timeout.Infinite != lockTimeout)
{
throw new ArgumentException(SR.Error_LockTimeout);
}
if (this.isReadOnly)
{
if (!lockManager.IsShared(lockMode))
{
throw new ArgumentException(SR.Error_LockMode);
}
}
if (this.enableStrict2PL == true && lockMode == LockMode.Shared)
{
this.ReplicatorTransactionBase.AddLockContext(this, LockContextMode.Read);
}
// Call the lock manager to get the lock.
var acquiredLock = await lockManager.AcquireLockAsync(this.id, lockResourceNameHash, lockMode, lockTimeout).ConfigureAwait(false);
Diagnostics.Assert(null != acquiredLock, this.tracer, "incorrect lock");
// Check is error has occured.
if (LockStatus.Invalid == acquiredLock.Status)
{
throw new TransactionFaultedException(string.Format(CultureInfo.CurrentCulture, SR.Error_ReplicatorTransactionInternallyAborted, this.Id));
}
if (LockStatus.Timeout == acquiredLock.Status)
{
throw new TimeoutException(
string.Format(
CultureInfo.CurrentCulture,
SR.LockTimeout_TStore_KeyLock,
lockMode,
this.tracer,
lockTimeout,
this.id,
lockResourceNameHash));
}
Diagnostics.Assert(LockStatus.Granted == acquiredLock.Status, this.tracer, "incorrect lock status");
Diagnostics.Assert(lockMode == acquiredLock.Mode, this.tracer, "incorrect lock mode");
Diagnostics.Assert(this.id == acquiredLock.Owner, this.tracer, "incorrect lock owner");
Diagnostics.Assert(0 < acquiredLock.Count, this.tracer, "incorrect lock count");
Diagnostics.Assert(null != acquiredLock.LockManager, this.tracer, "incorrect lock manager");
var releaseLastLockAcquired = false;
lock (this)
{
// It's possible that the store transaction has been terminated before this last lock was acquired.
releaseLastLockAcquired = (this.isClosed == true);
// Add the acquired lock only once to the lock list.
if (acquiredLock.Count == 1 && !releaseLastLockAcquired)
{
this.lockRequests.Add(acquiredLock);
}
}
if (releaseLastLockAcquired)
{
lockManager.ReleaseLock(acquiredLock);
throw new TransactionFaultedException(string.Format(CultureInfo.CurrentCulture, SR.Error_ReplicatorTransactionInternallyAborted, this.Id));
}
return(acquiredLock);
}
