5 // Jérémie "Garuma" Laval <jeremie.laval@gmail.com>
7 // Copyright (c) 2010 Jérémie "Garuma" Laval
9 // Permission is hereby granted, free of charge, to any person obtaining a copy
10 // of this software and associated documentation files (the "Software"), to deal
11 // in the Software without restriction, including without limitation the rights
12 // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
13 // copies of the Software, and to permit persons to whom the Software is
14 // furnished to do so, subject to the following conditions:
16 // The above copyright notice and this permission notice shall be included in
17 // all copies or substantial portions of the Software.
19 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
22 // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
23 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
24 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
30 using System.Threading;
31 using System.Collections.Generic;
33 namespace System.Linq.Parallel.QueryNodes
36 internal class QueryWhereNode<TSource> : QueryStreamNode<TSource, TSource>
38 Func<TSource, int, bool> indexedPredicate;
39 Func<TSource, bool> predicate;
41 internal QueryWhereNode (QueryBaseNode<TSource> parent, Func<TSource, bool> predicate)
42 : base (parent, false)
44 this.predicate = predicate;
47 internal QueryWhereNode (QueryBaseNode<TSource> parent, Func<TSource, int, bool> predicate)
50 this.indexedPredicate = predicate;
53 internal override IEnumerable<TSource> GetSequential ()
55 IEnumerable<TSource> parent = Parent.GetSequential ();
57 if (indexedPredicate != null)
58 return parent.Where (indexedPredicate);
60 return parent.Where (predicate);
63 internal override IList<IEnumerable<TSource>> GetEnumerablesIndexed (QueryOptions options)
65 return Parent.GetOrderedEnumerables (options)
66 .Select (i => i.Where (e => indexedPredicate (e.Value, (int)e.Key)).Select (e => e.Value))
70 internal override IList<IEnumerable<TSource>> GetEnumerablesNonIndexed (QueryOptions options)
72 return Parent.GetEnumerables (options)
73 .Select (i => i.Where (predicate))
77 internal override IList<IEnumerable<KeyValuePair<long, TSource>>> GetOrderedEnumerables (QueryOptions options)
79 IList<IEnumerable<KeyValuePair<long, TSource>>> sources = Parent.GetOrderedEnumerables (options);
81 ProcessingSlot[] store = new ProcessingSlot[sources.Count];
84 Barrier barrier = new Barrier (sources.Count, delegate (Barrier b) {
86 Array.Sort (store, ArraySortMethod);
88 // Reassign a good index
90 for (i = 0; i < store.Length && store[i].IsValid; ++i)
91 store[i].Index = lastIndex + i;
93 // Update lastIndex for next round
98 .Select ((s, i) => GetEnumerator (s, barrier, options.MergedToken, store, i))
102 static int ArraySortMethod (ProcessingSlot lhs, ProcessingSlot rhs)
104 if (lhs.IsValid && !rhs.IsValid)
106 if (!lhs.IsValid && rhs.IsValid)
108 if (!lhs.IsValid && !rhs.IsValid)
111 return lhs.Index < rhs.Index ? -1 : 1;
114 IEnumerable<KeyValuePair<long, TSource>> GetEnumerator (IEnumerable<KeyValuePair<long, TSource>> source,
116 CancellationToken token,
117 ProcessingSlot[] store, int index)
119 IEnumerator<KeyValuePair<long, TSource>> current = source.GetEnumerator ();
120 bool isIndexed = IsIndexed;
123 while (current.MoveNext ()) {
124 KeyValuePair<long, TSource> curr = current.Current;
126 bool result = isIndexed ? indexedPredicate (curr.Value, (int)curr.Key) : predicate (curr.Value);
127 store[index].Update (curr.Value, curr.Key, result);
129 barrier.SignalAndWait (token);
131 var value = store [index];
134 yield return new KeyValuePair<long, TSource> (value.Index, value.Value);
137 store[index].Clear ();
140 // Remove our participation
141 barrier.RemoveParticipant ();
146 struct ProcessingSlot
148 public TSource Value;
152 public void Update (TSource v, long i, bool t)
161 Update (default (TSource), long.MaxValue, false);