protected override byte[] GetSegment()
{
short requested = (short)SegmentSize;
short segmentLength = 0;
lock (_db)
{
// Clear the status vector
ClearStatusVector();
using (MemoryStream segment = new MemoryStream())
{
byte[] tmp = new byte[requested];
IntPtr status = _db.FbClient.isc_get_segment(
_statusVector,
ref _blobHandle,
ref segmentLength,
requested,
tmp);
if (segmentLength > 0)
{
segment.Write(tmp, 0, segmentLength > requested ? requested : segmentLength);
}
RblRemoveValue(IscCodes.RBL_segment);
if (_statusVector[1] == new IntPtr(IscCodes.isc_segstr_eof))
{
segment.SetLength(0);
RblAddValue(IscCodes.RBL_eof_pending);
}
else
{
if (status == IntPtr.Zero || _statusVector[1] == new IntPtr(IscCodes.isc_segment))
{
RblAddValue(IscCodes.RBL_segment);
}
else
{
_db.ParseStatusVector(_statusVector);
}
}
return(segment.ToArray());
}
}
}
public void BeginTransaction(TransactionParameterBuffer tpb)
{
if (_state != TransactionState.NoTransaction)
{
throw new IscException(IscCodes.isc_arg_gds, IscCodes.isc_tra_state, _handle, "no valid");
}
lock (_db)
{
IscTeb teb = new IscTeb();
IntPtr tebData = IntPtr.Zero;
try
{
// Clear the status vector
ClearStatusVector();
// Set db handle
teb.dbb_ptr = Marshal.AllocHGlobal(4);
Marshal.WriteInt32(teb.dbb_ptr, _db.Handle);
// Set tpb length
teb.tpb_len = tpb.Length;
// Set TPB data
teb.tpb_ptr = Marshal.AllocHGlobal(tpb.Length);
Marshal.Copy(tpb.ToArray(), 0, teb.tpb_ptr, tpb.Length);
// Alloc memory for the IscTeb structure
int size = Marshal.SizeOf(typeof(IscTeb));
tebData = Marshal.AllocHGlobal(size);
Marshal.StructureToPtr(teb, tebData, true);
int trHandle = _handle;
_db.FbClient.isc_start_multiple(
_statusVector,
ref trHandle,
1,
tebData);
_handle = trHandle;
// Parse status vector
_db.ParseStatusVector(_statusVector);
// Update transaction state
_state = TransactionState.Active;
// Update transaction count
_db.TransactionCount++;
}
catch
{
throw;
}
finally
{
// Free memory
if (teb.dbb_ptr != IntPtr.Zero)
{
Marshal.FreeHGlobal(teb.dbb_ptr);
}
if (teb.tpb_ptr != IntPtr.Zero)
{
Marshal.FreeHGlobal(teb.tpb_ptr);
}
if (tebData != IntPtr.Zero)
{
Marshal.DestroyStructure(tebData, typeof(IscTeb));
Marshal.FreeHGlobal(tebData);
}
}
}
}
public override void Prepare(string commandText)
{
// Clear data
ClearAll();
lock (_db)
{
// Clear the status vector
ClearStatusVector();
// Allocate the statement if needed
if (_state == StatementState.Deallocated)
{
Allocate();
}
// Marshal structures to pointer
XsqldaMarshaler marshaler = XsqldaMarshaler.Instance;
// Setup fields structure
_fields = new Descriptor(1);
IntPtr sqlda = marshaler.MarshalManagedToNative(_db.Charset, _fields);
int trHandle = _transaction.Handle;
int stmtHandle = _handle;
byte[] buffer = _db.Charset.GetBytes(commandText);
_db.FbClient.isc_dsql_prepare(
_statusVector,
ref trHandle,
ref stmtHandle,
(short)buffer.Length,
buffer,
_db.Dialect,
sqlda);
// Marshal Pointer
Descriptor descriptor = marshaler.MarshalNativeToManaged(_db.Charset, sqlda);
// Free memory
marshaler.CleanUpNativeData(ref sqlda);
// Parse status vector
_db.ParseStatusVector(_statusVector);
// Describe fields
_fields = descriptor;
if (_fields.ActualCount > 0 && _fields.ActualCount != _fields.Count)
{
Describe();
}
else
{
if (_fields.ActualCount == 0)
{
_fields = new Descriptor(0);
}
}
// Reset actual field values
_fields.ResetValues();
// Get Statement type
_statementType = GetStatementType();
// Update state
_state = StatementState.Prepared;
}
}
