|
//------------------------------------------------------------------------------
// <copyright file="SqlRecordBuffer.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
// <owner current="true" primary="true">Microsoft</owner>
// <owner current="true" primary="false">Microsoft</owner>
// <owner current="true" primary="false">Microsoft</owner>
//------------------------------------------------------------------------------
namespace Microsoft.SqlServer.Server {
using System;
using System.Data;
using System.Data.Common;
using System.Data.SqlTypes;
using System.Diagnostics;
using System.Runtime.InteropServices;
internal sealed class SqlRecordBuffer {
internal enum StorageType {
Boolean,
Byte,
ByteArray,
CharArray,
DateTime,
DateTimeOffset,
Double,
Guid,
Int16,
Int32,
Int64,
Single,
String,
SqlDecimal,
TimeSpan,
}
[StructLayout(LayoutKind.Explicit)]
internal struct Storage {
[FieldOffset(0)] internal Boolean _boolean;
[FieldOffset(0)] internal Byte _byte;
[FieldOffset(0)] internal DateTime _dateTime;
[FieldOffset(0)] internal DateTimeOffset _dateTimeOffset;
[FieldOffset(0)] internal Double _double;
[FieldOffset(0)] internal Guid _guid;
[FieldOffset(0)] internal Int16 _int16;
[FieldOffset(0)] internal Int32 _int32;
[FieldOffset(0)] internal Int64 _int64; // also used to BytesLength and CharsLength
[FieldOffset(0)] internal Single _single;
[FieldOffset(0)] internal TimeSpan _timeSpan;
}
private bool _isNull;
private StorageType _type;
private Storage _value;
private object _object; // String, SqlDecimal
private SmiMetaData _metadata; // for variant
private bool _isMetaSet; // flag to indicate whether we have set the variant metadata
internal SqlRecordBuffer(SmiMetaData metaData) {
_isNull = true;
}
internal bool IsNull {
get {
return _isNull;
}
}
internal Boolean Boolean {
get {
Debug.Assert(!_isNull, "Null data type");
Debug.Assert(StorageType.Boolean == _type, "Wrong storage type: " + _type);
return _value._boolean;
}
set {
_value._boolean = value;
_type = StorageType.Boolean;
_isNull = false;
}
}
internal Byte Byte {
get {
Debug.Assert(!_isNull, "Null data type");
Debug.Assert(StorageType.Byte == _type, "Wrong storage type: " + _type);
return _value._byte;
}
set {
_value._byte = value;
_type = StorageType.Byte;
_isNull = false;
}
}
internal DateTime DateTime {
get {
Debug.Assert(!_isNull, "Null data type");
Debug.Assert(StorageType.DateTime == _type, "Wrong storage type: " + _type);
return _value._dateTime;
}
set {
_value._dateTime = value;
_type = StorageType.DateTime;
_isNull = false;
// in case of variant types, the caller first sets metadata and than the value. we need to keep metadata after first value set
// if value is set second time without variant metadata, reset the metadata since it is not variant anymore
if (_isMetaSet) {
_isMetaSet = false;
} else {
_metadata = null; // need to clear the variant metadata
}
}
}
internal DateTimeOffset DateTimeOffset {
get {
Debug.Assert(!_isNull, "Null data type");
Debug.Assert(StorageType.DateTimeOffset == _type, "Wrong storage type: " + _type);
return _value._dateTimeOffset;
}
set {
_value._dateTimeOffset = value;
_type = StorageType.DateTimeOffset;
_isNull = false;
}
}
internal Double Double {
get {
Debug.Assert(!_isNull, "Null data type");
Debug.Assert(StorageType.Double == _type, "Wrong storage type: " + _type);
return _value._double;
}
set {
_value._double = value;
_type = StorageType.Double;
_isNull = false;
}
}
internal Guid Guid {
get {
Debug.Assert(!_isNull, "Null data type");
Debug.Assert(StorageType.Guid == _type, "Wrong storage type: " + _type);
return _value._guid;
}
set {
_value._guid = value;
_type = StorageType.Guid;
_isNull = false;
}
}
internal Int16 Int16 {
get {
Debug.Assert(!_isNull, "Null data type");
Debug.Assert(StorageType.Int16 == _type, "Wrong storage type: " + _type);
return _value._int16;
}
set {
_value._int16 = value;
_type = StorageType.Int16;
_isNull = false;
}
}
internal Int32 Int32 {
get {
Debug.Assert(!_isNull, "Null data type");
Debug.Assert(StorageType.Int32 == _type, "Wrong storage type: " + _type);
return _value._int32;
}
set {
_value._int32 = value;
_type = StorageType.Int32;
_isNull = false;
}
}
internal Int64 Int64 {
get {
Debug.Assert(!_isNull, "Null data type");
Debug.Assert(StorageType.Int64 == _type, "Wrong storage type: " + _type);
return _value._int64;
}
set {
_value._int64 = value;
_type = StorageType.Int64;
_isNull = false;
if (_isMetaSet) {
_isMetaSet = false;
} else {
_metadata = null; // need to clear the variant metadata
}
}
}
internal Single Single {
get {
Debug.Assert(!_isNull, "Null data type");
Debug.Assert(StorageType.Single == _type, "Wrong storage type: " + _type);
return _value._single;
}
set {
_value._single = value;
_type = StorageType.Single;
_isNull = false;
}
}
internal String String {
get {
Debug.Assert(!_isNull, "Null data type");
if (StorageType.String == _type) {
return (String)_object;
} else if (StorageType.CharArray == _type) {
return new String((char[])_object, 0, (int)CharsLength);
}
else {
// Xml may be stored as byte array, yet have GetString called against it.
Debug.Assert(StorageType.ByteArray == _type, "Wrong storage type: " + _type);
System.IO.Stream byteStream = new System.IO.MemoryStream((byte[])_object, false);
return (new SqlXml(byteStream)).Value;
}
}
set {
Debug.Assert(null != value, "");
_object = value;
_value._int64 = ((string)value).Length;
_type = StorageType.String;
_isNull = false;
if (_isMetaSet) {
_isMetaSet = false;
} else {
_metadata = null; // need to clear the variant metadata
}
}
}
internal SqlDecimal SqlDecimal {
get {
Debug.Assert(!_isNull, "Null data type");
Debug.Assert(StorageType.SqlDecimal == _type, "Wrong storage type: " + _type);
return (SqlDecimal)_object;
}
set {
Debug.Assert(!value.IsNull, "Null input");
_object = value;
_type = StorageType.SqlDecimal;
_isNull = false;
}
}
internal TimeSpan TimeSpan {
get {
Debug.Assert(!_isNull, "Null data type");
Debug.Assert(StorageType.TimeSpan == _type, "Wrong storage type: " + _type);
return _value._timeSpan;
}
set {
_value._timeSpan = value;
_type = StorageType.TimeSpan;
_isNull = false;
}
}
internal Int64 BytesLength {
get {
Debug.Assert(!_isNull, "Null data type");
// sometimes Xml is stored as string, but must support byte access
if (StorageType.String == _type) {
ConvertXmlStringToByteArray();
}
else {
Debug.Assert(StorageType.ByteArray == _type, "Wrong storage type: " + _type);
}
return _value._int64;
}
set {
if (0 == value) {
_value._int64 = value;
_object = new byte[0];
_type = StorageType.ByteArray;
_isNull = false;
} else {
Debug.Assert(!_isNull, "Null data type");
Debug.Assert(StorageType.ByteArray == _type, "Wrong storage type: " + _type);
Debug.Assert(value > 0 && value <= ((byte[])_object).Length, "Invalid BytesLength");
_value._int64 = value;
}
}
}
internal Int64 CharsLength {
get {
Debug.Assert(!_isNull, "Null data type");
Debug.Assert(StorageType.CharArray == _type || StorageType.String == _type, "Wrong storage type: " + _type);
return _value._int64;
}
set {
if (0 == value) {
_value._int64 = value;
_object = new char[0];
_type = StorageType.CharArray;
_isNull = false;
} else {
Debug.Assert(!_isNull, "Null data type");
Debug.Assert(StorageType.CharArray == _type || StorageType.String == _type, "Wrong storage type: " + _type);
Debug.Assert(value > 0 &&
((StorageType.CharArray == _type && value <= ((char[])_object).Length) || (StorageType.String == _type && value <= ((string)_object).Length)),
"Invalid CharsLength");
_value._int64 = value;
}
}
}
internal SmiMetaData VariantType {
get {
Debug.Assert(!_isNull, "Null data type");
Debug.Assert(_metadata == null
|| _metadata.SqlDbType == SqlDbType.Money
|| _metadata.SqlDbType == SqlDbType.NVarChar
|| _metadata.SqlDbType == SqlDbType.DateTime
|| _metadata.SqlDbType == SqlDbType.Date
|| _metadata.SqlDbType == SqlDbType.DateTime2,
"Invalid metadata");
switch (_type) {
case StorageType.Boolean: return SmiMetaData.DefaultBit;
case StorageType.Byte: return SmiMetaData.DefaultTinyInt;
case StorageType.ByteArray: return SmiMetaData.DefaultVarBinary;
case StorageType.CharArray: return SmiMetaData.DefaultNVarChar;
case StorageType.DateTime: return _metadata ?? SmiMetaData.DefaultDateTime;
case StorageType.DateTimeOffset: return SmiMetaData.DefaultDateTimeOffset;
case StorageType.Double: return SmiMetaData.DefaultFloat;
case StorageType.Guid: return SmiMetaData.DefaultUniqueIdentifier;
case StorageType.Int16: return SmiMetaData.DefaultSmallInt;
case StorageType.Int32: return SmiMetaData.DefaultInt;
case StorageType.Int64: return _metadata ?? SmiMetaData.DefaultBigInt;
case StorageType.Single: return SmiMetaData.DefaultReal;
case StorageType.String: return _metadata ?? SmiMetaData.DefaultNVarChar;
case StorageType.SqlDecimal: return new SmiMetaData(SqlDbType.Decimal, 17, ((SqlDecimal)_object).Precision, ((SqlDecimal)_object).Scale, 0, SqlCompareOptions.None, null);
case StorageType.TimeSpan: return SmiMetaData.DefaultTime;
}
return null;
}
set {
Debug.Assert(value != null && (value.SqlDbType == SqlDbType.Money || value.SqlDbType == SqlDbType.NVarChar),
"Invalid metadata");
_metadata = value;
_isMetaSet = true;
}
}
internal int GetBytes(long fieldOffset, byte[] buffer, int bufferOffset, int length) {
int ndataIndex = (int)fieldOffset;
Debug.Assert(!_isNull, "Null data type");
// sometimes Xml is stored as string, but must support byte access
if (StorageType.String == _type) {
ConvertXmlStringToByteArray();
}
else {
Debug.Assert(StorageType.ByteArray == _type, "Wrong storage type: " + _type);
}
Debug.Assert (null != buffer, "Null buffer");
Debug.Assert(ndataIndex + length <= BytesLength, "Invalid fieldOffset or length");
Buffer.BlockCopy((byte[])_object, ndataIndex, buffer, bufferOffset, length);
return length;
}
internal int GetChars(long fieldOffset, char[] buffer, int bufferOffset, int length) {
int ndataIndex = (int)fieldOffset;
Debug.Assert(!_isNull, "Null data type");
Debug.Assert(StorageType.CharArray == _type || StorageType.String == _type, "Wrong storage type: " + _type);
Debug.Assert (null != buffer, "Null buffer");
Debug.Assert(ndataIndex + length <= CharsLength, "Invalid fieldOffset or length");
if (StorageType.CharArray == _type) {
Array.Copy((char[])_object, ndataIndex, buffer, bufferOffset, length);
} else { // String type
((string)_object).CopyTo(ndataIndex, buffer, bufferOffset, length);
}
return length;
}
internal int SetBytes(long fieldOffset, byte[] buffer, int bufferOffset, int length) {
int ndataIndex = (int)fieldOffset;
if (IsNull || StorageType.ByteArray != _type) {
if (ndataIndex != 0) { // set the first time: should start from the beginning
throw ADP.ArgumentOutOfRange("fieldOffset");
}
_object = new byte[length];
_type = StorageType.ByteArray;
_isNull = false;
BytesLength = length;
} else {
if (ndataIndex > BytesLength) { // no gap is allowed
throw ADP.ArgumentOutOfRange("fieldOffset");
}
if (ndataIndex + length > BytesLength) { // beyond the current length
int cbytes = ((byte[])_object).Length;
if (ndataIndex + length > cbytes) { // dynamic expansion
byte[] data = new byte[Math.Max(ndataIndex + length, 2 * cbytes)];
Buffer.BlockCopy((byte[])_object, 0, data, 0, (int)BytesLength);
_object = data;
}
BytesLength = ndataIndex + length;
}
}
Buffer.BlockCopy(buffer, bufferOffset, (byte[])_object, ndataIndex, length);
return length;
}
internal int SetChars(long fieldOffset, char[] buffer, int bufferOffset, int length) {
int ndataIndex = (int)fieldOffset;
if (IsNull || (StorageType.CharArray != _type && StorageType.String != _type)) {
if (ndataIndex != 0) { // set the first time: should start from the beginning
throw ADP.ArgumentOutOfRange("fieldOffset");
}
_object = new char[length];
_type = StorageType.CharArray;
_isNull = false;
CharsLength = length;
} else {
if (ndataIndex > CharsLength) { // no gap is allowed
throw ADP.ArgumentOutOfRange("fieldOffset");
}
if (StorageType.String == _type) { // convert string to char[]
_object = ((string)_object).ToCharArray();
_type = StorageType.CharArray;
}
if (ndataIndex + length > CharsLength) { // beyond the current length
int cchars = ((char[])_object).Length;
if (ndataIndex + length > cchars) { // dynamic expansion
char[] data = new char[Math.Max(ndataIndex + length, 2 * cchars)];
Array.Copy((char[])_object, 0, data, 0, CharsLength);
_object = data;
}
CharsLength = ndataIndex + length;
}
}
Array.Copy(buffer, bufferOffset, (char[])_object, ndataIndex, length);
return length;
}
internal void SetNull() {
_isNull = true;
}
// Handle case for Xml where SetString() was called, followed by GetBytes()
private void ConvertXmlStringToByteArray() {
Debug.Assert(StorageType.String == _type, "ConvertXmlStringToByteArray: Invalid storage type for conversion: " + _type.ToString());
// Grab the unicode bytes, but prepend the XML unicode BOM
string value = (string)_object;
byte[] bytes = new byte[2 + System.Text.Encoding.Unicode.GetByteCount(value)];
bytes[0] = 0xff;
bytes[1] = 0xfe;
System.Text.Encoding.Unicode.GetBytes(value, 0, value.Length, bytes, 2);
_object = bytes;
_value._int64 = bytes.Length;
_type = StorageType.ByteArray;
}
}
}
|