internal SequenceNumber Append(IList <ArraySegment <byte> > data,
SequenceNumber nextUndoRecord,
SequenceNumber previousRecord,
bool forceFlush)
{
TruncateIfNecessary();
bool lockHeld = false;
try
{
try { }
finally
{
appendLock.AcquireReaderLock(-1);
lockHeld = true;
}
using (AppendHelper helper = new AppendHelper(
data,
previousRecord,
nextUndoRecord,
false))
{
return(log.AppendRecord(helper.Blobs, forceFlush));
}
}
finally
{
if (lockHeld)
{
appendLock.ReleaseReaderLock();
}
}
}
internal SequenceNumber WriteRestartAreaInternal(
IList<ArraySegment<byte>> data,
SequenceNumber newBaseSeqNum)
{
if (data == null)
{
throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(Error.ArgumentNull("data"));
}
TruncateIfNecessary();
bool lockHeld = false;
try
{
try { }
finally
{
appendLock.AcquireWriterLock(-1);
lockHeld = true;
}
SequenceNumber sn;
AppendHelper helper;
bool lastSeqNum, firstSeqNum;
lastSeqNum = newBaseSeqNum == this.LastSequenceNumber;
firstSeqNum = newBaseSeqNum == this.BaseSequenceNumber;
if (lastSeqNum)
{
// We dont know the new base sequence number.
// It will be the sequence number we get from append.
helper = new AppendHelper(data,
this.lastRestartArea,
SequenceNumber.Invalid,
true);
}
else
{
if (!firstSeqNum)
{
ValidateSequenceNumber(newBaseSeqNum);
// Validate newBaseSequenceNumber by reading the corresponding record.
int cbData = 1;
byte[] record;
int recordSize;
SequenceNumber prev, next;
// Sequence number validation checks if the Seq Num > BSN and Seq Num < LSN.
// Now we validate if Seq Number is a valid number in this sequence.
try
{
this.log.ReadRecordPrefix(newBaseSeqNum, out record, ref cbData, out recordSize, out prev, out next);
}
catch (ArgumentException exception)
{
throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(Error.ArgumentOutOfRange(SR.Argument_TailInvalid, exception));
}
}
helper = new AppendHelper(data,
this.lastRestartArea,
newBaseSeqNum,
true);
}
// If there is a failure betweeen append and truncate,
// then the log will be in an inconsistent state. To
// solve this, we write the new base sequence number in
// the header. During recovery from failure, we will find
// the restart area and truncate the log.
using (helper)
{
// No need for a reader appendLock, since WriteRestartAreaInternal is under a lock.
sn = this.log.AppendRecord(helper.Blobs, true);
}
this.lastRestartArea = sn;
if (firstSeqNum)
{
return sn;
}
if (lastSeqNum)
{
newBaseSeqNum = sn;
}
try
{
log.TruncatePrefix(newBaseSeqNum);
}
#pragma warning suppress 56500
catch (Exception exception)
{
this.newBaseSeqNum = newBaseSeqNum;
this.truncateFailed = true;
if (Fx.IsFatal(exception)) throw;
}
return sn;
}
finally
{
if (lockHeld)
{
appendLock.ReleaseWriterLock();
}
}
}
internal SequenceNumber Append(IList<ArraySegment<byte>> data,
SequenceNumber nextUndoRecord,
SequenceNumber previousRecord,
bool forceFlush)
{
TruncateIfNecessary();
bool lockHeld = false;
try
{
try { }
finally
{
appendLock.AcquireReaderLock(-1);
lockHeld = true;
}
using (AppendHelper helper = new AppendHelper(
data,
previousRecord,
nextUndoRecord,
false))
{
return log.AppendRecord(helper.Blobs, forceFlush);
}
}
finally
{
if (lockHeld)
{
appendLock.ReleaseReaderLock();
}
}
}
internal SequenceNumber WriteRestartAreaInternal(
IList <ArraySegment <byte> > data,
SequenceNumber newBaseSeqNum)
{
if (data == null)
{
throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(Error.ArgumentNull("data"));
}
TruncateIfNecessary();
bool lockHeld = false;
try
{
try { }
finally
{
appendLock.AcquireWriterLock(-1);
lockHeld = true;
}
SequenceNumber sn;
AppendHelper helper;
bool lastSeqNum, firstSeqNum;
lastSeqNum = newBaseSeqNum == this.LastSequenceNumber;
firstSeqNum = newBaseSeqNum == this.BaseSequenceNumber;
if (lastSeqNum)
{
// We dont know the new base sequence number.
// It will be the sequence number we get from append.
helper = new AppendHelper(data,
this.lastRestartArea,
SequenceNumber.Invalid,
true);
}
else
{
if (!firstSeqNum)
{
ValidateSequenceNumber(newBaseSeqNum);
// Validate newBaseSequenceNumber by reading the corresponding record.
int cbData = 1;
byte[] record;
int recordSize;
SequenceNumber prev, next;
// Sequence number validation checks if the Seq Num > BSN and Seq Num < LSN.
// Now we validate if Seq Number is a valid number in this sequence.
try
{
this.log.ReadRecordPrefix(newBaseSeqNum, out record, ref cbData, out recordSize, out prev, out next);
}
catch (ArgumentException exception)
{
throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(Error.ArgumentOutOfRange(SR.Argument_TailInvalid, exception));
}
}
helper = new AppendHelper(data,
this.lastRestartArea,
newBaseSeqNum,
true);
}
// If there is a failure betweeen append and truncate,
// then the log will be in an inconsistent state. To
// solve this, we write the new base sequence number in
// the header. During recovery from failure, we will find
// the restart area and truncate the log.
using (helper)
{
// No need for a reader appendLock, since WriteRestartAreaInternal is under a lock.
sn = this.log.AppendRecord(helper.Blobs, true);
}
this.lastRestartArea = sn;
if (firstSeqNum)
{
return(sn);
}
if (lastSeqNum)
{
newBaseSeqNum = sn;
}
try
{
log.TruncatePrefix(newBaseSeqNum);
}
#pragma warning suppress 56500
catch (Exception exception)
{
this.newBaseSeqNum = newBaseSeqNum;
this.truncateFailed = true;
if (Fx.IsFatal(exception))
{
throw;
}
}
return(sn);
}
finally
{
if (lockHeld)
{
appendLock.ReleaseWriterLock();
}
}
}