/// <summary>
/// Loads Btrieve Key Definitions from the Btrieve DAT File Header
/// </summary>
private void LoadBtrieveKeyDefinitions()
{
ushort keyDefinitionBase = 0x110;
const ushort keyDefinitionLength = 0x1E;
ReadOnlySpan <byte> btrieveFileContentSpan = LoadedFile.Data;
//Check for Log Key
if (btrieveFileContentSpan[0x10C] == 1)
{
_logger.Warn($"Btireve Log Key Present in {LoadedFile.FileName}");
LoadedFile.LogKeyPresent = true;
}
ushort totalKeys = LoadedFile.KeyCount;
ushort currentKeyNumber = 0;
ushort previousKeyNumber = 0;
while (currentKeyNumber < totalKeys)
{
var keyDefinition = new BtrieveKeyDefinition {
Data = btrieveFileContentSpan.Slice(keyDefinitionBase, keyDefinitionLength).ToArray()
};
if (keyDefinition.Attributes.HasFlag(EnumKeyAttributeMask.SegmentedKey))
{
keyDefinition.SegmentOf = previousKeyNumber;
keyDefinition.Number = previousKeyNumber;
}
else
{
keyDefinition.Number = currentKeyNumber;
currentKeyNumber++;
}
#if DEBUG
_logger.Info("----------------");
_logger.Info("Loaded Key Definition:");
_logger.Info("----------------");
_logger.Info($"Number: {keyDefinition.Number}");
_logger.Info($"Total Records: {keyDefinition.TotalRecords}");
_logger.Info($"Data Type: {keyDefinition.DataType}");
_logger.Info($"Attributes: {keyDefinition.Attributes}");
_logger.Info($"Position: {keyDefinition.Position}");
_logger.Info($"Length: {keyDefinition.Length}");
_logger.Info("----------------");
#endif
if (!LoadedFile.Keys.TryGetValue(keyDefinition.Number, out var key))
{
key = new BtrieveKey(keyDefinition);
LoadedFile.Keys.Add(keyDefinition.Number, key);
}
else
{
key.Segments.Add(keyDefinition);
}
keyDefinitionBase += keyDefinitionLength;
}
}
/// <summary>
/// Loads metadata from the loaded Sqlite table, such as RecordLength and all the key metadata.
/// </summary>
private void LoadSqliteMetadata()
{
using (var cmd = new SqliteCommand("SELECT record_length, page_length, variable_length_records FROM metadata_t;", _connection))
{
using var reader = cmd.ExecuteReader();
try
{
if (!reader.Read())
{
throw new ArgumentException($"Can't read metadata_t from {FullPath}");
}
RecordLength = reader.GetInt32(0);
PageLength = reader.GetInt32(1);
VariableLengthRecords = reader.GetBoolean(2);
}
finally
{
reader.Close();
}
}
using (var cmd =
new SqliteCommand(
"SELECT number, segment, attributes, data_type, offset, length FROM keys_t ORDER BY number, segment;",
_connection))
{
using var reader = cmd.ExecuteReader();
while (reader.Read())
{
var number = reader.GetInt32(0);
var btrieveKeyDefinition = new BtrieveKeyDefinition()
{
Number = (ushort)number,
Segment = reader.GetInt32(1) != 0,
SegmentOf = reader.GetInt32(1) != 0 ? (ushort)number : (ushort)0,
Attributes = (EnumKeyAttributeMask)reader.GetInt32(2),
DataType = (EnumKeyDataType)reader.GetInt32(3),
Offset = (ushort)reader.GetInt32(4),
Length = (ushort)reader.GetInt32(5),
};
if (!Keys.TryGetValue(btrieveKeyDefinition.Number, out var btrieveKey))
{
btrieveKey = new BtrieveKey();
Keys[btrieveKeyDefinition.Number] = btrieveKey;
}
var index = btrieveKey.Segments.Count;
btrieveKeyDefinition.SegmentIndex = index;
btrieveKey.Segments.Add(btrieveKeyDefinition);
if (btrieveKeyDefinition.DataType == EnumKeyDataType.AutoInc)
{
AutoincrementedKeys[btrieveKeyDefinition.Number] = btrieveKey;
}
}
reader.Close();
}
}
/// <summary>
/// Loads Btrieve Key Definitions from the Btrieve DAT File Header
/// </summary>
private void LoadBtrieveKeyDefinitions(ILogger logger)
{
var keyDefinitionBase = 0x110;
const ushort keyDefinitionLength = 0x1E;
var btrieveFileContentSpan = Data.AsSpan();
LogKeyPresent = (btrieveFileContentSpan[0x10C] == 1);
var totalKeys = KeyCount;
var currentKeyNumber = (ushort)0;
while (currentKeyNumber < totalKeys)
{
var data = btrieveFileContentSpan.Slice(keyDefinitionBase, keyDefinitionLength).ToArray();
EnumKeyDataType dataType;
var attributes = (EnumKeyAttributeMask)BitConverter.ToUInt16(data, 0x8);
if (attributes.HasFlag(EnumKeyAttributeMask.UseExtendedDataType))
{
dataType = (EnumKeyDataType)data[0x1C];
}
else
{
dataType = attributes.HasFlag(EnumKeyAttributeMask.OldStyleBinary) ? EnumKeyDataType.OldBinary : EnumKeyDataType.OldAscii;
}
var keyDefinition = new BtrieveKeyDefinition {
Number = currentKeyNumber,
Attributes = attributes,
DataType = dataType,
Offset = BitConverter.ToUInt16(data, 0x14),
Length = BitConverter.ToUInt16(data, 0x16),
Segment = attributes.HasFlag(EnumKeyAttributeMask.SegmentedKey),
SegmentOf = attributes.HasFlag(EnumKeyAttributeMask.SegmentedKey) ? currentKeyNumber : (ushort)0,
NullValue = data[0x1D],
};
if (keyDefinition.RequiresACS)
{
if (ACS == null)
{
throw new ArgumentException($"Key {keyDefinition.Number} requires ACS, but none was read. This database is likely corrupt: {FileName}");
}
keyDefinition.ACS = ACS;
}
//If it's a segmented key, don't increment so the next key gets added to the same ordinal as an additional segment
if (!keyDefinition.Segment)
{
currentKeyNumber++;
}
#if DEBUG
logger.Info("----------------");
logger.Info("Loaded Key Definition:");
logger.Info("----------------");
logger.Info($"Number: {keyDefinition.Number}");
logger.Info($"Data Type: {keyDefinition.DataType}");
logger.Info($"Attributes: {keyDefinition.Attributes}");
logger.Info($"Offset: {keyDefinition.Offset}");
logger.Info($"Length: {keyDefinition.Length}");
logger.Info($"Segment: {keyDefinition.Segment}");
logger.Info($"SegmentOf: {keyDefinition.SegmentOf}");
logger.Info("----------------");
#endif
if (!Keys.TryGetValue(keyDefinition.Number, out var key))
{
key = new BtrieveKey(keyDefinition);
Keys.Add(keyDefinition.Number, key);
}
else
{
key.Segments.Add(keyDefinition);
}
keyDefinitionBase += keyDefinitionLength;
}
// update segment indices
foreach (var key in Keys)
{
var i = 0;
foreach (var segment in key.Value.Segments)
{
segment.SegmentIndex = i++;
}
}
}