Skip to content

Commit

Permalink
Optimize the SqlGuid struct (#72549)
Browse files Browse the repository at this point in the history 
* Optimize the SqlGuid struct

Optimizes the SqlGuid struct according to the idea
from #51836.

* Update SQLGuid.cs

* Apply suggestions

* Update SQLGuid.cs

* Update SQLGuid.cs

* Update ref assembly

* Update System.Data.Common.cs

* Apply suggestions

* Update SQLGuid.cs

* Update SQLGuid.cs

* Update SQLGuid.cs

* Add a comment about binary serialization

* Expand on the comment for backwards-compatible binary serialization

---------

Co-authored-by: Jeff Handley <[email protected]>
  • Loading branch information
@MichalPetryka @jeffhandley
MichalPetryka and jeffhandley authored Jan 30, 2023
1 parent 5d604a8 commit bf5afd4
Show file tree
Hide file tree
Showing 2 changed files with 55 additions and 59 deletions.
4 changes: 2 additions & 2 deletions src/libraries/System.Data.Common/ref/System.Data.Common.cs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -3224,9 +3224,8 @@ void System.Xml.Serialization.IXmlSerializable.WriteXml(System.Xml.XmlWriter wri
public override string ToString() { throw null; }
}
[System.Xml.Serialization.XmlSchemaProviderAttribute("GetXsdType")]
public partial struct SqlGuid : System.Data.SqlTypes.INullable, System.IComparable, System.Xml.Serialization.IXmlSerializable, System.IEquatable<System.Data.SqlTypes.SqlGuid>
public partial struct SqlGuid : System.Data.SqlTypes.INullable, System.IComparable, System.Runtime.Serialization.ISerializable, System.Xml.Serialization.IXmlSerializable, System.IEquatable<System.Data.SqlTypes.SqlGuid>
{
private object _dummy;
private int _dummyPrimitive;
public static readonly System.Data.SqlTypes.SqlGuid Null;
public SqlGuid(byte[] value) { throw null; }
Expand Down Expand Up @@ -3261,6 +3260,7 @@ public partial struct SqlGuid : System.Data.SqlTypes.INullable, System.IComparab
System.Xml.Schema.XmlSchema System.Xml.Serialization.IXmlSerializable.GetSchema() { throw null; }
void System.Xml.Serialization.IXmlSerializable.ReadXml(System.Xml.XmlReader reader) { }
void System.Xml.Serialization.IXmlSerializable.WriteXml(System.Xml.XmlWriter writer) { }
void System.Runtime.Serialization.ISerializable.GetObjectData(System.Runtime.Serialization.SerializationInfo info, System.Runtime.Serialization.StreamingContext context) { }
public byte[]? ToByteArray() { throw null; }
public System.Data.SqlTypes.SqlBinary ToSqlBinary() { throw null; }
public System.Data.SqlTypes.SqlString ToSqlString() { throw null; }
Expand Down
110 changes: 53 additions & 57 deletions src/libraries/System.Data.Common/src/System/Data/SQLTypes/SQLGuid.cs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -2,6 +2,10 @@
// The .NET Foundation licenses this file to you under the MIT license.

using System.Data.Common;
using System.Diagnostics;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using System.Runtime.Serialization;
using System.Xml;
using System.Xml.Schema;
using System.Xml.Serialization;
Expand All @@ -16,71 +20,60 @@ namespace System.Data.SqlTypes
[Serializable]
[XmlSchemaProvider("GetXsdType")]
[System.Runtime.CompilerServices.TypeForwardedFrom("System.Data, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089")]
public struct SqlGuid : INullable, IComparable, IXmlSerializable, IEquatable<SqlGuid>
public struct SqlGuid : INullable, IComparable, ISerializable, IXmlSerializable, IEquatable<SqlGuid>
{
private const int SizeOfGuid = 16;
private const int SizeOfGuid = 16; // sizeof(Guid)

// NOTE: If any instance fields change, update SqlTypeWorkarounds type in System.Data.SqlClient.
private byte[]? m_value; // the SqlGuid is null if m_value is null
private Guid? _value; // the SqlGuid is null if _value is null

// constructor
// construct a SqlGuid.Null
private SqlGuid(bool _)
{
m_value = null;
}

public SqlGuid(byte[] value)
{
if (value == null || value.Length != SizeOfGuid)
throw new ArgumentException(SQLResource.InvalidArraySizeMessage);

m_value = new byte[SizeOfGuid];
value.CopyTo(m_value, 0);
}

internal SqlGuid(byte[] value, bool _)
{
if (value == null || value.Length != SizeOfGuid)
throw new ArgumentException(SQLResource.InvalidArraySizeMessage);

m_value = value;
_value = new Guid(value);
}

public SqlGuid(string s)
{
m_value = (new Guid(s)).ToByteArray();
_value = new Guid(s);
}

public SqlGuid(Guid g)
{
m_value = g.ToByteArray();
_value = g;
}

public SqlGuid(int a, short b, short c, byte d, byte e, byte f, byte g, byte h, byte i, byte j, byte k)
: this(new Guid(a, b, c, d, e, f, g, h, i, j, k))
{
}


// INullable
public bool IsNull
// Maintains backwards-compatible binary serialization for the `private byte[] m_value` field
// see src/libraries/System.Runtime.Serialization.Formatters/tests/BinaryFormatterTestData.cs
// for test data
private SqlGuid(SerializationInfo info, StreamingContext context)
{
get { return (m_value is null); }
byte[]? value = (byte[]?)info.GetValue("m_value", typeof(byte[]));
if (value is null)
_value = null;
else
_value = new Guid(value);
}

// property: Value
public Guid Value
void ISerializable.GetObjectData(SerializationInfo info, StreamingContext context)
{
get
{
if (m_value is null)
throw new SqlNullValueException();
else
return new Guid(m_value);
}
info.AddValue("m_value", ToByteArray(), typeof(byte[]));
}

// INullable
public bool IsNull => _value is null;

// property: Value
public Guid Value => _value ?? throw new SqlNullValueException();

// Implicit conversion from Guid to SqlGuid
public static implicit operator SqlGuid(Guid x)
{
Expand All @@ -95,18 +88,17 @@ public static explicit operator Guid(SqlGuid x)

public byte[]? ToByteArray()
{
byte[] ret = new byte[SizeOfGuid];
m_value!.CopyTo(ret, 0); // TODO: NRE
return ret;
if (_value is null)
return null;
return _value.GetValueOrDefault().ToByteArray();
}

public override string ToString()
{
if (m_value is null)
if (_value is null)
return SQLResource.NullString;

Guid g = new Guid(m_value);
return g.ToString();
return _value.GetValueOrDefault().ToString();
}

public static SqlGuid Parse(string s)
Expand All @@ -117,16 +109,24 @@ public static SqlGuid Parse(string s)
return new SqlGuid(s);
}


// Comparison operators
private static EComparison Compare(SqlGuid x, SqlGuid y)
{
// Comparison orders.
ReadOnlySpan<byte> rgiGuidOrder = new byte[16] { 10, 11, 12, 13, 14, 15, 8, 9, 6, 7, 4, 5, 0, 1, 2, 3 };
ReadOnlySpan<byte> rgiGuidOrder = new byte[SizeOfGuid] { 10, 11, 12, 13, 14, 15, 8, 9, 6, 7, 4, 5, 0, 1, 2, 3 };

Debug.Assert(!x.IsNull);
Debug.Assert(!y.IsNull);

// Swap to the correct order to be compared
ReadOnlySpan<byte> xBytes = x.m_value;
ReadOnlySpan<byte> yBytes = y.m_value;
Span<byte> xBytes = stackalloc byte[SizeOfGuid];
bool xWrote = x._value.GetValueOrDefault().TryWriteBytes(xBytes);
Debug.Assert(xWrote);

Span<byte> yBytes = stackalloc byte[SizeOfGuid];
bool yWrote = y._value.GetValueOrDefault().TryWriteBytes(yBytes);
Debug.Assert(yWrote);

for (int i = 0; i < SizeOfGuid; i++)
{
byte b1 = xBytes[rgiGuidOrder[i]];
Expand All @@ -140,8 +140,6 @@ private static EComparison Compare(SqlGuid x, SqlGuid y)
return EComparison.EQ;
}



// Implicit conversions

// Explicit conversions
Expand All @@ -161,7 +159,8 @@ public static explicit operator SqlGuid(SqlBinary x)
// Overloading comparison operators
public static SqlBoolean operator ==(SqlGuid x, SqlGuid y)
{
return (x.IsNull || y.IsNull) ? SqlBoolean.Null : new SqlBoolean(Compare(x, y) == EComparison.EQ);
return (x.IsNull || y.IsNull) ? SqlBoolean.Null :
new SqlBoolean(x._value.GetValueOrDefault() == y._value.GetValueOrDefault());
}

public static SqlBoolean operator !=(SqlGuid x, SqlGuid y)
Expand Down Expand Up @@ -249,7 +248,6 @@ public SqlBinary ToSqlBinary()
return (SqlBinary)this;
}


// IComparable
// Compares this object to another object, returning an integer that
// indicates the relationship.
Expand Down Expand Up @@ -287,12 +285,10 @@ public override bool Equals([NotNullWhen(true)] object? value) =>
/// <summary>Indicates whether the current instance is equal to another instance of the same type.</summary>
/// <param name="other">An instance to compare with this instance.</param>
/// <returns>true if the current instance is equal to the other instance; otherwise, false.</returns>
public bool Equals(SqlGuid other) =>
other.IsNull || IsNull ? other.IsNull && IsNull :
(this == other).Value;
public bool Equals(SqlGuid other) => _value == other._value;

// For hashing purpose
public override int GetHashCode() => IsNull ? 0 : Value.GetHashCode();
public override int GetHashCode() => _value.GetHashCode();

XmlSchema? IXmlSerializable.GetSchema() { return null; }

Expand All @@ -303,23 +299,23 @@ void IXmlSerializable.ReadXml(XmlReader reader)
{
// Read the next value.
reader.ReadElementString();
m_value = null;
_value = null;
}
else
{
m_value = new Guid(reader.ReadElementString()).ToByteArray();
_value = new Guid(reader.ReadElementString());
}
}

void IXmlSerializable.WriteXml(XmlWriter writer)
{
if (m_value is null)
if (_value is null)
{
writer.WriteAttributeString("xsi", "nil", XmlSchema.InstanceNamespace, "true");
}
else
{
writer.WriteString(XmlConvert.ToString(new Guid(m_value)));
writer.WriteString(XmlConvert.ToString(_value.GetValueOrDefault()));
}
}

Expand All @@ -328,6 +324,6 @@ public static XmlQualifiedName GetXsdType(XmlSchemaSet schemaSet)
return new XmlQualifiedName("string", XmlSchema.Namespace);
}

public static readonly SqlGuid Null = new SqlGuid(true);
public static readonly SqlGuid Null;
} // SqlGuid
} // namespace System.Data.SqlTypes

0 comments on commit bf5afd4

Please sign in to comment.