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// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
using System.Collections.Generic;
using System.ComponentModel;
using System.Diagnostics;
using System.Diagnostics.CodeAnalysis;
using System.Threading;
namespace System.Data
{
internal readonly struct IndexField : IEquatable<IndexField>
{
public readonly DataColumn Column;
public readonly bool IsDescending; // false = Asc; true = Desc what is default value for this?
internal IndexField(DataColumn column, bool isDescending)
{
Debug.Assert(column != null, "null column");
Column = column;
IsDescending = isDescending;
}
public static bool operator ==(IndexField if1, IndexField if2) => if1.Equals(if2);
public static bool operator !=(IndexField if1, IndexField if2) => !if1.Equals(if2);
// must override Equals if == operator is defined
public override bool Equals([NotNullWhen(true)] object? obj) =>
obj is IndexField other && Equals(other);
public bool Equals(IndexField other) => Column == other.Column && IsDescending == other.IsDescending;
// must override GetHashCode if Equals is redefined
public override int GetHashCode() =>
Column.GetHashCode() ^ IsDescending.GetHashCode();
}
internal sealed class Index
{
private sealed class IndexTree : RBTree<int>
{
private readonly Index _index;
internal IndexTree(Index index) : base(TreeAccessMethod.KEY_SEARCH_AND_INDEX)
{
_index = index;
}
protected override int CompareNode(int record1, int record2) =>
_index.CompareRecords(record1, record2);
protected override int CompareSatelliteTreeNode(int record1, int record2) =>
_index.CompareDuplicateRecords(record1, record2);
}
// these constants are used to update a DataRow when the record and Row are known, but don't match
private const int DoNotReplaceCompareRecord = 0;
private const int ReplaceNewRecordForCompare = 1;
private const int ReplaceOldRecordForCompare = 2;
private readonly DataTable _table;
internal readonly IndexField[] _indexFields;
/// <summary>Allow a user implemented comparison of two DataRow</summary>
/// <remarks>User must use correct DataRowVersion in comparison or index corruption will happen</remarks>
private readonly System.Comparison<DataRow>? _comparison;
private readonly DataViewRowState _recordStates;
private readonly WeakReference? _rowFilter;
private IndexTree _records = null!; // Always initialized in InitRecords
private int _recordCount;
private int _refCount;
private readonly Listeners<DataViewListener> _listeners;
private bool _suspendEvents;
private readonly bool _isSharable;
private readonly bool _hasRemoteAggregate;
internal const int MaskBits = unchecked(0x7FFFFFFF);
private static int s_objectTypeCount; // Bid counter
private readonly int _objectID = Interlocked.Increment(ref s_objectTypeCount);
public Index(DataTable table, IndexField[] indexFields, DataViewRowState recordStates, IFilter? rowFilter) :
this(table, indexFields, null, recordStates, rowFilter)
{
}
public Index(DataTable table, System.Comparison<DataRow> comparison, DataViewRowState recordStates, IFilter? rowFilter) :
this(table, GetAllFields(table.Columns), comparison, recordStates, rowFilter)
{
}
// for the delegate methods, we don't know what the dependent columns are - so all columns are dependent
private static IndexField[] GetAllFields(DataColumnCollection columns)
{
IndexField[] fields = new IndexField[columns.Count];
for (int i = 0; i < fields.Length; ++i)
{
fields[i] = new IndexField(columns[i], false);
}
return fields;
}
private Index(DataTable table, IndexField[] indexFields, System.Comparison<DataRow>? comparison, DataViewRowState recordStates, IFilter? rowFilter)
{
DataCommonEventSource.Log.Trace("<ds.Index.Index|API> {0}, table={1}, recordStates={2}",
ObjectID, (table != null) ? table.ObjectID : 0, recordStates);
Debug.Assert(indexFields != null);
Debug.Assert(null != table, "null table");
if ((recordStates &
(~(DataViewRowState.CurrentRows | DataViewRowState.OriginalRows))) != 0)
{
throw ExceptionBuilder.RecordStateRange();
}
_table = table;
_listeners = new Listeners<DataViewListener>(ObjectID, listener => null != listener);
_indexFields = indexFields;
_recordStates = recordStates;
_comparison = comparison;
_isSharable = (rowFilter == null) && (comparison == null); // a filter or comparison make an index unsharable
if (null != rowFilter)
{
_rowFilter = new WeakReference(rowFilter);
DataExpression? expr = (rowFilter as DataExpression);
if (null != expr)
{
_hasRemoteAggregate = expr.HasRemoteAggregate();
}
}
InitRecords(rowFilter);
// do not AddRef in ctor, every caller should be responsible to AddRef it
// if caller does not AddRef, it is expected to be a one-time read operation because the index won't be maintained on writes
}
public bool Equal(IndexField[] indexDesc, DataViewRowState recordStates, IFilter? rowFilter)
{
if (!_isSharable ||
_indexFields.Length != indexDesc.Length ||
_recordStates != recordStates ||
null != rowFilter)
{
return false;
}
for (int loop = 0; loop < _indexFields.Length; loop++)
{
if (_indexFields[loop].Column != indexDesc[loop].Column ||
_indexFields[loop].IsDescending != indexDesc[loop].IsDescending)
{
return false;
}
}
return true;
}
internal bool HasRemoteAggregate => _hasRemoteAggregate;
internal int ObjectID => _objectID;
public DataViewRowState RecordStates => _recordStates;
public IFilter? RowFilter => (IFilter?)(_rowFilter?.Target);
public int GetRecord(int recordIndex)
{
Debug.Assert(recordIndex >= 0 && recordIndex < _recordCount, "recordIndex out of range");
return _records[recordIndex];
}
public bool HasDuplicates => _records.HasDuplicates;
public int RecordCount => _recordCount;
public bool IsSharable => _isSharable;
private bool AcceptRecord(int record) => AcceptRecord(record, RowFilter);
private bool AcceptRecord(int record, IFilter? filter)
{
DataCommonEventSource.Log.Trace("<ds.Index.AcceptRecord|API> {0}, record={1}", ObjectID, record);
if (filter == null)
{
return true;
}
DataRow? row = _table._recordManager[record];
if (row == null)
{
return true;
}
DataRowVersion version = DataRowVersion.Default;
if (row._oldRecord == record)
{
version = DataRowVersion.Original;
}
else if (row._newRecord == record)
{
version = DataRowVersion.Current;
}
else if (row._tempRecord == record)
{
version = DataRowVersion.Proposed;
}
return filter.Invoke(row, version);
}
/// <remarks>Only call from inside a lock(this)</remarks>
internal void ListChangedAdd(DataViewListener listener) => _listeners.Add(listener);
/// <remarks>Only call from inside a lock(this)</remarks>
internal void ListChangedRemove(DataViewListener listener) => _listeners.Remove(listener);
public int RefCount => _refCount;
public void AddRef()
{
DataCommonEventSource.Log.Trace("<ds.Index.AddRef|API> {0}", ObjectID);
_table._indexesLock.EnterWriteLock();
try
{
Debug.Assert(0 <= _refCount, "AddRef on disposed index");
Debug.Assert(null != _records, "null records");
if (_refCount == 0)
{
_table.ShadowIndexCopy();
_table._indexes.Add(this);
}
_refCount++;
}
finally
{
_table._indexesLock.ExitWriteLock();
}
}
public int RemoveRef()
{
DataCommonEventSource.Log.Trace("<ds.Index.RemoveRef|API> {0}", ObjectID);
int count;
_table._indexesLock.EnterWriteLock();
try
{
count = --_refCount;
if (_refCount <= 0)
{
_table.ShadowIndexCopy();
_table._indexes.Remove(this);
}
}
finally
{
_table._indexesLock.ExitWriteLock();
}
return count;
}
private void ApplyChangeAction(int record, int action, int changeRecord)
{
if (action != 0)
{
if (action > 0)
{
if (AcceptRecord(record))
{
InsertRecord(record, true);
}
}
else if ((null != _comparison) && (-1 != record))
{
// when removing a record, the DataRow has already been updated to the newer record
// depending on changeRecord, either the new or old record needs be backdated to record
// for Comparison<DataRow> to operate correctly
DeleteRecord(GetIndex(record, changeRecord));
}
else
{
// unnecessary codepath other than keeping original code path for redbits
DeleteRecord(GetIndex(record));
}
}
}
public bool CheckUnique()
{
#if DEBUG
Debug.Assert(_records.CheckUnique(_records.root) != HasDuplicates, "CheckUnique difference");
#endif
return !HasDuplicates;
}
// only used for main tree compare, not satalite tree
private int CompareRecords(int record1, int record2)
{
if (null != _comparison)
{
return CompareDataRows(record1, record2);
}
if (0 < _indexFields.Length)
{
for (int i = 0; i < _indexFields.Length; i++)
{
int c = _indexFields[i].Column.Compare(record1, record2);
if (c != 0)
{
return (_indexFields[i].IsDescending ? -c : c);
}
}
return 0;
}
else
{
var (row1, row2) = (_table._recordManager[record1], _table._recordManager[record2]);
Debug.Assert(null != row1, "record1 no datarow");
Debug.Assert(null != row2, "record2 no datarow");
// Need to use compare because subtraction will wrap
// to positive for very large neg numbers, etc.
return _table.Rows.IndexOf(row1).CompareTo(_table.Rows.IndexOf(row2));
}
}
private int CompareDataRows(int record1, int record2)
{
_table._recordManager.VerifyRecord(record1, _table._recordManager[record1]);
_table._recordManager.VerifyRecord(record2, _table._recordManager[record2]);
return _comparison!(_table._recordManager[record1], _table._recordManager[record2]);
}
// PS: same as previous CompareRecords, except it compares row state if needed
// only used for satalite tree compare
private int CompareDuplicateRecords(int record1, int record2)
{
#if DEBUG
if (null != _comparison)
{
Debug.Assert(0 == CompareDataRows(record1, record2), "duplicate record not a duplicate by user function");
}
else if (record1 != record2)
{
for (int i = 0; i < _indexFields.Length; i++)
{
int c = _indexFields[i].Column.Compare(record1, record2);
Debug.Assert(0 == c, "duplicate record not a duplicate");
}
}
#endif
var (row1, row2) = (_table._recordManager[record1], _table._recordManager[record2]);
Debug.Assert(null != row1, "record1 no datarow");
Debug.Assert(null != row2, "record2 no datarow");
if (null == row1)
{
return ((null == row2) ? 0 : -1);
}
else if (null == row2)
{
return 1;
}
// Need to use compare because subtraction will wrap
// to positive for very large neg numbers, etc.
int diff = row1.rowID.CompareTo(row2.rowID);
// if they're two records in the same row, we need to be able to distinguish them.
if ((diff == 0) && (record1 != record2))
{
diff = ((int)row1.GetRecordState(record1)).CompareTo((int)row2.GetRecordState(record2));
}
return diff;
}
private int CompareRecordToKey(int record1, object?[] vals)
{
for (int i = 0; i < _indexFields.Length; i++)
{
int c = _indexFields[i].Column.CompareValueTo(record1, vals[i]);
if (c != 0)
{
return (_indexFields[i].IsDescending ? -c : c);
}
}
return 0;
}
// DeleteRecordFromIndex deletes the given record from index and does not fire any Event. IT SHOULD NOT FIRE EVENT
public void DeleteRecordFromIndex(int recordIndex)
{
// this is for expression use, to maintain expression columns's sort , filter etc. do not fire event
DeleteRecord(recordIndex, false);
}
// old and existing DeleteRecord behavior, we can not use this for silently deleting
private void DeleteRecord(int recordIndex)
{
DeleteRecord(recordIndex, true);
}
private void DeleteRecord(int recordIndex, bool fireEvent)
{
DataCommonEventSource.Log.Trace("<ds.Index.DeleteRecord|INFO> {0}, recordIndex={1}, fireEvent={2}", ObjectID, recordIndex, fireEvent);
if (recordIndex >= 0)
{
_recordCount--;
int record = _records.DeleteByIndex(recordIndex);
MaintainDataView(ListChangedType.ItemDeleted, record, !fireEvent);
if (fireEvent)
{
OnListChanged(ListChangedType.ItemDeleted, recordIndex);
}
}
}
// this improves performance by allowing DataView to iterating instead of computing for records over index
// this will also allow Linq over DataSet to enumerate over the index
// avoid boxing by returning RBTreeEnumerator (a struct) instead of IEnumerator<int>
public RBTree<int>.RBTreeEnumerator GetEnumerator(int startIndex) =>
new IndexTree.RBTreeEnumerator(_records, startIndex);
// What it actually does is find the index in the records[] that
// this record inhabits, and if it doesn't, suggests what index it would
// inhabit while setting the high bit.
public int GetIndex(int record) => _records.GetIndexByKey(record);
/// <summary>
/// When searching by value for a specific record, the DataRow may require backdating to reflect the appropriate state
/// otherwise on Delete of a DataRow in the Added state, would result in the <see cref="System.Comparison<DataRow>"/> where the row
/// reflection record would be in the Detached instead of Added state.
/// </summary>
private int GetIndex(int record, int changeRecord)
{
Debug.Assert(null != _comparison, "missing comparison");
int index;
DataRow row = _table._recordManager[record]!;
int a = row._newRecord;
int b = row._oldRecord;
try
{
switch (changeRecord)
{
case ReplaceNewRecordForCompare:
row._newRecord = record;
break;
case ReplaceOldRecordForCompare:
row._oldRecord = record;
break;
}
_table._recordManager.VerifyRecord(record, row);
index = _records.GetIndexByKey(record);
}
finally
{
switch (changeRecord)
{
case ReplaceNewRecordForCompare:
Debug.Assert(record == row._newRecord, "newRecord has change during GetIndex");
row._newRecord = a;
break;
case ReplaceOldRecordForCompare:
Debug.Assert(record == row._oldRecord, "oldRecord has change during GetIndex");
row._oldRecord = b;
break;
}
#if DEBUG
if (-1 != a)
{
_table._recordManager.VerifyRecord(a, row);
}
#endif
}
return index;
}
public object[] GetUniqueKeyValues()
{
if (_indexFields == null || _indexFields.Length == 0)
{
return Array.Empty<object>();
}
List<object[]> list = new List<object[]>();
GetUniqueKeyValues(list, _records.root);
return list.ToArray();
}
/// <summary>
/// Find index of maintree node that matches key in record
/// </summary>
public int FindRecord(int record)
{
int nodeId = _records.Search(record);
if (nodeId != IndexTree.NIL)
return _records.GetIndexByNode(nodeId); //always returns the First record index
else
return -1;
}
public int FindRecordByKey(object? key)
{
int nodeId = FindNodeByKey(key);
if (IndexTree.NIL != nodeId)
{
return _records.GetIndexByNode(nodeId);
}
return -1; // return -1 to user indicating record not found
}
public int FindRecordByKey(object?[] key)
{
int nodeId = FindNodeByKeys(key);
if (IndexTree.NIL != nodeId)
{
return _records.GetIndexByNode(nodeId);
}
return -1; // return -1 to user indicating record not found
}
private int FindNodeByKey(object? originalKey)
{
int x, c;
if (_indexFields.Length != 1)
{
throw ExceptionBuilder.IndexKeyLength(_indexFields.Length, 1);
}
x = _records.root;
if (IndexTree.NIL != x)
{
// otherwise storage may not exist
DataColumn column = _indexFields[0].Column;
object? key = column.ConvertValue(originalKey);
x = _records.root;
if (_indexFields[0].IsDescending)
{
while (IndexTree.NIL != x)
{
c = column.CompareValueTo(_records.Key(x), key);
if (c == 0) { break; }
if (c < 0) { x = _records.Left(x); } // < for decsending
else { x = _records.Right(x); }
}
}
else
{
while (IndexTree.NIL != x)
{
c = column.CompareValueTo(_records.Key(x), key);
if (c == 0) { break; }
if (c > 0) { x = _records.Left(x); } // > for ascending
else { x = _records.Right(x); }
}
}
}
return x;
}
private int FindNodeByKeys(object?[]? originalKey)
{
int x, c;
c = ((null != originalKey) ? originalKey.Length : 0);
if (originalKey is null || 0 == c || _indexFields.Length != c)
{
throw ExceptionBuilder.IndexKeyLength(_indexFields.Length, c);
}
x = _records.root;
if (IndexTree.NIL != x)
{
// otherwise storage may not exist
// copy array to avoid changing original
object?[] key = new object?[originalKey.Length];
for (int i = 0; i < originalKey.Length; ++i)
{
key[i] = _indexFields[i].Column.ConvertValue(originalKey[i]);
}
x = _records.root;
while (IndexTree.NIL != x)
{
c = CompareRecordToKey(_records.Key(x), key);
if (c == 0) { break; }
if (c > 0) { x = _records.Left(x); }
else { x = _records.Right(x); }
}
}
return x;
}
private int FindNodeByKeyRecord(int record)
{
int x, c;
x = _records.root;
if (IndexTree.NIL != x)
{
// otherwise storage may not exist
x = _records.root;
while (IndexTree.NIL != x)
{
c = CompareRecords(_records.Key(x), record);
if (c == 0) { break; }
if (c > 0) { x = _records.Left(x); }
else { x = _records.Right(x); }
}
}
return x;
}
internal delegate int ComparisonBySelector<TKey, TRow>(TKey key, TRow row) where TRow : DataRow;
/// <summary>This method exists for LinqDataView to keep a level of abstraction away from the RBTree</summary>
internal Range FindRecords<TKey, TRow>(ComparisonBySelector<TKey, TRow> comparison, TKey key) where TRow : DataRow
{
int x = _records.root;
while (IndexTree.NIL != x)
{
int c = comparison(key, (TRow)_table._recordManager[_records.Key(x)]!);
if (c == 0) { break; }
if (c < 0) { x = _records.Left(x); }
else { x = _records.Right(x); }
}
return GetRangeFromNode(x);
}
private Range GetRangeFromNode(int nodeId)
{
// fill range with the min and max indexes of matching record (i.e min and max of satellite tree)
// min index is the index of the node in main tree, and max is the min + size of satellite tree-1
if (IndexTree.NIL == nodeId)
{
return default;
}
int recordIndex = _records.GetIndexByNode(nodeId);
if (_records.Next(nodeId) == IndexTree.NIL)
return new Range(recordIndex, recordIndex);
int span = _records.SubTreeSize(_records.Next(nodeId));
return new Range(recordIndex, recordIndex + span - 1);
}
public Range FindRecords(object? key)
{
int nodeId = FindNodeByKey(key); // main tree node associated with key
return GetRangeFromNode(nodeId);
}
public Range FindRecords(object?[] key)
{
int nodeId = FindNodeByKeys(key); // main tree node associated with key
return GetRangeFromNode(nodeId);
}
internal void FireResetEvent()
{
DataCommonEventSource.Log.Trace("<ds.Index.FireResetEvent|API> {0}", ObjectID);
if (DoListChanged)
{
OnListChanged(DataView.s_resetEventArgs);
}
}
private int GetChangeAction(DataViewRowState oldState, DataViewRowState newState)
{
int oldIncluded = ((int)_recordStates & (int)oldState) == 0 ? 0 : 1;
int newIncluded = ((int)_recordStates & (int)newState) == 0 ? 0 : 1;
return newIncluded - oldIncluded;
}
/// <summary>Determine if the record that needs backdating is the newRecord or oldRecord or neither</summary>
private static int GetReplaceAction(DataViewRowState oldState)
{
return ((0 != (DataViewRowState.CurrentRows & oldState)) ? ReplaceNewRecordForCompare : // Added/ModifiedCurrent/Unchanged
((0 != (DataViewRowState.OriginalRows & oldState)) ? ReplaceOldRecordForCompare : // Deleted/ModififedOriginal
DoNotReplaceCompareRecord)); // None
}
public DataRow GetRow(int i) => _table._recordManager[GetRecord(i)];
public DataRow[] GetRows(object[] values) => GetRows(FindRecords(values));
public DataRow[] GetRows(Range range)
{
DataRow[] newRows = _table.NewRowArray(range.Count);
if (0 < newRows.Length)
{
RBTree<int>.RBTreeEnumerator iterator = GetEnumerator(range.Min);
for (int i = 0; i < newRows.Length && iterator.MoveNext(); i++)
{
newRows[i] = _table._recordManager[iterator.Current];
}
}
return newRows;
}
private void InitRecords(IFilter? filter)
{
DataViewRowState states = _recordStates;
// this improves performance when the is no filter, like with the default view (creating after rows added)
// we know the records are in the correct order, just append to end, duplicates not possible
bool append = (0 == _indexFields.Length);
_records = new IndexTree(this);
_recordCount = 0;
// this improves performance by iterating of the index instead of computing record by index
foreach (DataRow b in _table.Rows)
{
int record = -1;
if (b._oldRecord == b._newRecord)
{
if ((states & DataViewRowState.Unchanged) != 0)
{
record = b._oldRecord;
}
}
else if (b._oldRecord == -1)
{
if ((states & DataViewRowState.Added) != 0)
{
record = b._newRecord;
}
}
else if (b._newRecord == -1)
{
if ((states & DataViewRowState.Deleted) != 0)
{
record = b._oldRecord;
}
}
else
{
if ((states & DataViewRowState.ModifiedCurrent) != 0)
{
record = b._newRecord;
}
else if ((states & DataViewRowState.ModifiedOriginal) != 0)
{
record = b._oldRecord;
}
}
if (record != -1 && AcceptRecord(record, filter))
{
_records.InsertAt(-1, record, append);
_recordCount++;
}
}
}
// InsertRecordToIndex inserts the given record to index and does not fire any Event. IT SHOULD NOT FIRE EVENT
// I added this since I can not use existing InsertRecord which is not silent operation
// it returns the position that record is inserted
public int InsertRecordToIndex(int record)
{
int pos = -1;
if (AcceptRecord(record))
{
pos = InsertRecord(record, false);
}
return pos;
}
// existing functionality, it calls the overload with fireEvent== true, so it still fires the event
private int InsertRecord(int record, bool fireEvent)
{
DataCommonEventSource.Log.Trace("<ds.Index.InsertRecord|INFO> {0}, record={1}, fireEvent={2}", ObjectID, record, fireEvent);
// this improves performance when the is no filter, like with the default view (creating before rows added)
// we know can append when the new record is the last row in table, normal insertion pattern
bool append = false;
if ((0 == _indexFields.Length) && (null != _table))
{
DataRow row = _table._recordManager[record];
append = (_table.Rows.IndexOf(row) + 1 == _table.Rows.Count);
}
int nodeId = _records.InsertAt(-1, record, append);
_recordCount++;
MaintainDataView(ListChangedType.ItemAdded, record, !fireEvent);
if (fireEvent)
{
if (DoListChanged)
{
OnListChanged(ListChangedType.ItemAdded, _records.GetIndexByNode(nodeId));
}
return 0;
}
else
{
return _records.GetIndexByNode(nodeId);
}
}
// Search for specified key
public bool IsKeyInIndex(object key)
{
int x_id = FindNodeByKey(key);
return (IndexTree.NIL != x_id);
}
public bool IsKeyInIndex(object[] key)
{
int x_id = FindNodeByKeys(key);
return (IndexTree.NIL != x_id);
}
public bool IsKeyRecordInIndex(int record)
{
int x_id = FindNodeByKeyRecord(record);
return (IndexTree.NIL != x_id);
}
private bool DoListChanged => (!_suspendEvents && _listeners.HasListeners && !_table.AreIndexEventsSuspended);
private void OnListChanged(ListChangedType changedType, int newIndex, int oldIndex)
{
if (DoListChanged)
{
OnListChanged(new ListChangedEventArgs(changedType, newIndex, oldIndex));
}
}
private void OnListChanged(ListChangedType changedType, int index)
{
if (DoListChanged)
{
OnListChanged(new ListChangedEventArgs(changedType, index));
}
}
private void OnListChanged(ListChangedEventArgs e)
{
DataCommonEventSource.Log.Trace("<ds.Index.OnListChanged|INFO> {0}", ObjectID);
Debug.Assert(DoListChanged, "supposed to check DoListChanged before calling to delay create ListChangedEventArgs");
_listeners.Notify(e, false, false,
delegate (DataViewListener listener, ListChangedEventArgs args, bool arg2, bool arg3)
{
listener.IndexListChanged(args);
});
}
private void MaintainDataView(ListChangedType changedType, int record, bool trackAddRemove)
{
Debug.Assert(-1 <= record, "bad record#");
_listeners.Notify(changedType, ((0 <= record) ? _table._recordManager[record] : null), trackAddRemove,
delegate (DataViewListener listener, ListChangedType type, DataRow? row, bool track)
{
listener.MaintainDataView(changedType, row, track);
});
}
public void Reset()
{
DataCommonEventSource.Log.Trace("<ds.Index.Reset|API> {0}", ObjectID);
InitRecords(RowFilter);
MaintainDataView(ListChangedType.Reset, -1, false);
FireResetEvent();
}
public void RecordChanged(int record)
{
DataCommonEventSource.Log.Trace("<ds.Index.RecordChanged|API> {0}, record={1}", ObjectID, record);
if (DoListChanged)
{
int index = GetIndex(record);
if (index >= 0)
{
OnListChanged(ListChangedType.ItemChanged, index);
}
}
}
// new RecordChanged which takes oldIndex and newIndex and fires _onListChanged
public void RecordChanged(int oldIndex, int newIndex)
{
DataCommonEventSource.Log.Trace("<ds.Index.RecordChanged|API> {0}, oldIndex={1}, newIndex={2}", ObjectID, oldIndex, newIndex);
if (oldIndex > -1 || newIndex > -1)
{
// no need to fire if it was not and will not be in index: this check means at least one version should be in index
if (oldIndex == newIndex)
{
OnListChanged(ListChangedType.ItemChanged, newIndex, oldIndex);
}
else if (oldIndex == -1)
{
// it is added
OnListChanged(ListChangedType.ItemAdded, newIndex, oldIndex);
}
else if (newIndex == -1)
{
OnListChanged(ListChangedType.ItemDeleted, oldIndex);
}
else
{
OnListChanged(ListChangedType.ItemMoved, newIndex, oldIndex);
}
}
}
public void RecordStateChanged(int record, DataViewRowState oldState, DataViewRowState newState)
{
DataCommonEventSource.Log.Trace("<ds.Index.RecordStateChanged|API> {0}, record={1}, oldState={2}, newState={3}", ObjectID, record, oldState, newState);
int action = GetChangeAction(oldState, newState);
ApplyChangeAction(record, action, GetReplaceAction(oldState));
}
public void RecordStateChanged(int oldRecord, DataViewRowState oldOldState, DataViewRowState oldNewState,
int newRecord, DataViewRowState newOldState, DataViewRowState newNewState)
{
DataCommonEventSource.Log.Trace("<ds.Index.RecordStateChanged|API> {0}, oldRecord={1}, oldOldState={2}, oldNewState={3}, newRecord={4}, newOldState={5}, newNewState={6}",
ObjectID, oldRecord, oldOldState, oldNewState, newRecord, newOldState, newNewState);
Debug.Assert((-1 == oldRecord) || (-1 == newRecord) ||
_table._recordManager[oldRecord] == _table._recordManager[newRecord],
"not the same DataRow when updating oldRecord and newRecord");
int oldAction = GetChangeAction(oldOldState, oldNewState);
int newAction = GetChangeAction(newOldState, newNewState);
if (oldAction == -1 && newAction == 1 && AcceptRecord(newRecord))
{
int oldRecordIndex;
if ((null != _comparison) && oldAction < 0)
{ // when oldRecord is being removed, allow GetIndexByKey updating the DataRow for Comparison<DataRow>
oldRecordIndex = GetIndex(oldRecord, GetReplaceAction(oldOldState));
}
else
{
oldRecordIndex = GetIndex(oldRecord);
}
if ((null == _comparison) && oldRecordIndex != -1 && CompareRecords(oldRecord, newRecord) == 0)
{
_records.UpdateNodeKey(oldRecord, newRecord); //change in place, as Both records have same key value
int commonIndexLocation = GetIndex(newRecord);
OnListChanged(ListChangedType.ItemChanged, commonIndexLocation, commonIndexLocation);
}
else
{
_suspendEvents = true;
if (oldRecordIndex != -1)
{
_records.DeleteByIndex(oldRecordIndex); // DeleteByIndex doesn't require searching by key
_recordCount--;
}
_records.Insert(newRecord);
_recordCount++;
_suspendEvents = false;
int newRecordIndex = GetIndex(newRecord);
if (oldRecordIndex == newRecordIndex)
{ // if the position is the same
OnListChanged(ListChangedType.ItemChanged, newRecordIndex, oldRecordIndex); // be carefull remove oldrecord index if needed
}
else
{
if (oldRecordIndex == -1)
{
MaintainDataView(ListChangedType.ItemAdded, newRecord, false);
OnListChanged(ListChangedType.ItemAdded, GetIndex(newRecord)); // oldLocation would be -1
}
else
{
OnListChanged(ListChangedType.ItemMoved, newRecordIndex, oldRecordIndex);
}
}
}
}
else
{
ApplyChangeAction(oldRecord, oldAction, GetReplaceAction(oldOldState));
ApplyChangeAction(newRecord, newAction, GetReplaceAction(newOldState));
}
}
internal DataTable Table => _table;
private void GetUniqueKeyValues(List<object[]> list, int curNodeId)
{
if (curNodeId != IndexTree.NIL)
{
GetUniqueKeyValues(list, _records.Left(curNodeId));
int record = _records.Key(curNodeId);
object[] element = new object[_indexFields.Length]; // number of columns in PK
for (int j = 0; j < element.Length; ++j)
{
element[j] = _indexFields[j].Column[record];
}
list.Add(element);
GetUniqueKeyValues(list, _records.Right(curNodeId));
}
}
internal static int IndexOfReference<T>(List<T?>? list, T item) where T : class
{
if (null != list)
{
for (int i = 0; i < list.Count; ++i)
{
if (ReferenceEquals(list[i], item))
{
return i;
}
}
}
return -1;
}
internal static bool ContainsReference<T>(List<T?> list, T item) where T : class
{
return (0 <= IndexOfReference(list, item));
}
}
internal sealed class Listeners<TElem> where TElem : class
{
private readonly List<TElem?> _listeners;
private readonly Func<TElem?, bool> _filter;
private readonly int _objectID;
private int _listenerReaderCount;
/// <summary>Wish this was defined in mscorlib.dll instead of System.Core.dll</summary>
internal delegate void Action<T1, T2, T3, T4>(T1 arg1, T2 arg2, T3 arg3, T4 arg4);
/// <summary>Wish this was defined in mscorlib.dll instead of System.Core.dll</summary>
internal delegate TResult Func<T1, TResult>(T1 arg1);
internal Listeners(int ObjectID, Func<TElem?, bool> notifyFilter)
{
_listeners = new List<TElem?>();
_filter = notifyFilter;
_objectID = ObjectID;
_listenerReaderCount = 0;
}
internal bool HasListeners => (0 < _listeners.Count);
/// <remarks>Only call from inside a lock</remarks>
internal void Add(TElem listener)
{
Debug.Assert(null != listener, "null listener");
Debug.Assert(!Index.ContainsReference(_listeners, listener), "already contains reference");
_listeners.Add(listener);
}
internal int IndexOfReference(TElem listener)
{
return Index.IndexOfReference(_listeners, listener);
}
/// <remarks>Only call from inside a lock</remarks>
internal void Remove(TElem listener)
{
Debug.Assert(null != listener, "null listener");
int index = IndexOfReference(listener);
Debug.Assert(0 <= index, "listeners don't contain listener");
_listeners[index] = null;
if (0 == _listenerReaderCount)
{
_listeners.RemoveAt(index);
_listeners.TrimExcess();
}
}
/// <summary>
/// Write operation which means user must control multi-thread and we can assume single thread
/// </summary>
internal void Notify<T1, T2, T3>(T1 arg1, T2 arg2, T3 arg3, Action<TElem, T1, T2, T3> action)
{
Debug.Assert(null != action, "no action");
Debug.Assert(0 <= _listenerReaderCount, "negative _listEventCount");
int count = _listeners.Count;
if (0 < count)
{
int nullIndex = -1;
// protect against listeners shrinking via Remove
_listenerReaderCount++;
try
{
// protect against listeners growing via Add since new listeners will already have the Notify in progress
for (int i = 0; i < count; ++i)
{
// protect against listener being set to null (instead of being removed)
TElem? listener = _listeners[i];
if (_filter(listener))
{
// perform the action on each listener
// some actions may throw an exception blocking remaining listeners from being notified (just like events)
action(listener!, arg1, arg2, arg3);
}
else
{
_listeners[i] = null;
nullIndex = i;
}
}
}
finally
{
_listenerReaderCount--;
}
if (0 == _listenerReaderCount)
{
RemoveNullListeners(nullIndex);
}
}
}
private void RemoveNullListeners(int nullIndex)
{
Debug.Assert((-1 == nullIndex) || (null == _listeners[nullIndex]), "non-null listener");
Debug.Assert(0 == _listenerReaderCount, "0 < _listenerReaderCount");
for (int i = nullIndex; 0 <= i; --i)
{
if (null == _listeners[i])
{
_listeners.RemoveAt(i);
}
}
}
}
}
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