diff options
Diffstat (limited to 'csharp/src/Google.Protobuf/Collections')
| -rw-r--r-- | csharp/src/Google.Protobuf/Collections/Lists.cs | 89 | ||||
| -rw-r--r-- | csharp/src/Google.Protobuf/Collections/MapField.cs | 22 | ||||
| -rw-r--r-- | csharp/src/Google.Protobuf/Collections/ProtobufEqualityComparers.cs | 130 | ||||
| -rw-r--r--[-rwxr-xr-x] | csharp/src/Google.Protobuf/Collections/RepeatedField.cs | 5 |
4 files changed, 233 insertions, 13 deletions
diff --git a/csharp/src/Google.Protobuf/Collections/Lists.cs b/csharp/src/Google.Protobuf/Collections/Lists.cs new file mode 100644 index 00000000..860795ce --- /dev/null +++ b/csharp/src/Google.Protobuf/Collections/Lists.cs @@ -0,0 +1,89 @@ +#region Copyright notice and license +// Protocol Buffers - Google's data interchange format +// Copyright 2017 Google Inc. All rights reserved. +// https://developers.google.com/protocol-buffers/ +// +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following disclaimer +// in the documentation and/or other materials provided with the +// distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived from +// this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +#endregion + +using System.Collections.Generic; +using System.Collections.ObjectModel; + +namespace Google.Protobuf.Collections +{ + /// <summary> + /// Utility to compare if two Lists are the same, and the hash code + /// of a List. + /// </summary> + public static class Lists + { + /// <summary> + /// Checks if two lists are equal. + /// </summary> + public static bool Equals<T>(List<T> left, List<T> right) + { + if (left == right) + { + return true; + } + if (left == null || right == null) + { + return false; + } + if (left.Count != right.Count) + { + return false; + } + IEqualityComparer<T> comparer = EqualityComparer<T>.Default; + for (int i = 0; i < left.Count; i++) + { + if (!comparer.Equals(left[i], right[i])) + { + return false; + } + } + return true; + } + + /// <summary> + /// Gets the list's hash code. + /// </summary> + public static int GetHashCode<T>(List<T> list) + { + if (list == null) + { + return 0; + } + int hash = 31; + foreach (T element in list) + { + hash = hash * 29 + element.GetHashCode(); + } + return hash; + } + } +}
\ No newline at end of file diff --git a/csharp/src/Google.Protobuf/Collections/MapField.cs b/csharp/src/Google.Protobuf/Collections/MapField.cs index 8dac8e30..dbbcc148 100644 --- a/csharp/src/Google.Protobuf/Collections/MapField.cs +++ b/csharp/src/Google.Protobuf/Collections/MapField.cs @@ -71,9 +71,12 @@ namespace Google.Protobuf.Collections , IReadOnlyDictionary<TKey, TValue> #endif { + private static readonly EqualityComparer<TValue> ValueEqualityComparer = ProtobufEqualityComparers.GetEqualityComparer<TValue>(); + private static readonly EqualityComparer<TKey> KeyEqualityComparer = ProtobufEqualityComparers.GetEqualityComparer<TKey>(); + // TODO: Don't create the map/list until we have an entry. (Assume many maps will be empty.) private readonly Dictionary<TKey, LinkedListNode<KeyValuePair<TKey, TValue>>> map = - new Dictionary<TKey, LinkedListNode<KeyValuePair<TKey, TValue>>>(); + new Dictionary<TKey, LinkedListNode<KeyValuePair<TKey, TValue>>>(KeyEqualityComparer); private readonly LinkedList<KeyValuePair<TKey, TValue>> list = new LinkedList<KeyValuePair<TKey, TValue>>(); /// <summary> @@ -131,11 +134,8 @@ namespace Google.Protobuf.Collections return map.ContainsKey(key); } - private bool ContainsValue(TValue value) - { - var comparer = EqualityComparer<TValue>.Default; - return list.Any(pair => comparer.Equals(pair.Value, value)); - } + private bool ContainsValue(TValue value) => + list.Any(pair => ValueEqualityComparer.Equals(pair.Value, value)); /// <summary> /// Removes the entry identified by the given key from the map. @@ -293,8 +293,7 @@ namespace Google.Protobuf.Collections bool ICollection<KeyValuePair<TKey, TValue>>.Contains(KeyValuePair<TKey, TValue> item) { TValue value; - return TryGetValue(item.Key, out value) - && EqualityComparer<TValue>.Default.Equals(item.Value, value); + return TryGetValue(item.Key, out value) && ValueEqualityComparer.Equals(item.Value, value); } /// <summary> @@ -363,11 +362,12 @@ namespace Google.Protobuf.Collections /// </returns> public override int GetHashCode() { - var valueComparer = EqualityComparer<TValue>.Default; + var keyComparer = KeyEqualityComparer; + var valueComparer = ValueEqualityComparer; int hash = 0; foreach (var pair in list) { - hash ^= pair.Key.GetHashCode() * 31 + valueComparer.GetHashCode(pair.Value); + hash ^= keyComparer.GetHashCode(pair.Key) * 31 + valueComparer.GetHashCode(pair.Value); } return hash; } @@ -394,7 +394,7 @@ namespace Google.Protobuf.Collections { return false; } - var valueComparer = EqualityComparer<TValue>.Default; + var valueComparer = ValueEqualityComparer; foreach (var pair in this) { TValue value; diff --git a/csharp/src/Google.Protobuf/Collections/ProtobufEqualityComparers.cs b/csharp/src/Google.Protobuf/Collections/ProtobufEqualityComparers.cs new file mode 100644 index 00000000..13ef60fc --- /dev/null +++ b/csharp/src/Google.Protobuf/Collections/ProtobufEqualityComparers.cs @@ -0,0 +1,130 @@ +#region Copyright notice and license +// Protocol Buffers - Google's data interchange format +// Copyright 2017 Google Inc. All rights reserved. +// https://developers.google.com/protocol-buffers/ +// +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following disclaimer +// in the documentation and/or other materials provided with the +// distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived from +// this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +#endregion + +using System; +using System.Collections.Generic; + +namespace Google.Protobuf.Collections +{ + /// <summary> + /// Provides a central place to implement equality comparisons, primarily for bitwise float/double equality. + /// </summary> + public static class ProtobufEqualityComparers + { + /// <summary> + /// Returns an equality comparer for <typeparamref name="T"/> suitable for Protobuf equality comparisons. + /// This is usually just the default equality comparer for the type, but floating point numbers are compared + /// bitwise. + /// </summary> + /// <typeparam name="T">The type of equality comparer to return.</typeparam> + /// <returns>The equality comparer.</returns> + public static EqualityComparer<T> GetEqualityComparer<T>() + { + return typeof(T) == typeof(double) ? (EqualityComparer<T>) (object) BitwiseDoubleEqualityComparer + : typeof(T) == typeof(float) ? (EqualityComparer<T>) (object) BitwiseSingleEqualityComparer + : typeof(T) == typeof(double?) ? (EqualityComparer<T>) (object) BitwiseNullableDoubleEqualityComparer + : typeof(T) == typeof(float?) ? (EqualityComparer<T>) (object) BitwiseNullableSingleEqualityComparer + : EqualityComparer<T>.Default; + } + + /// <summary> + /// Returns an equality comparer suitable for comparing 64-bit floating point values, by bitwise comparison. + /// (NaN values are considered equal, but only when they have the same representation.) + /// </summary> + public static EqualityComparer<double> BitwiseDoubleEqualityComparer { get; } = new BitwiseDoubleEqualityComparerImpl(); + + /// <summary> + /// Returns an equality comparer suitable for comparing 32-bit floating point values, by bitwise comparison. + /// (NaN values are considered equal, but only when they have the same representation.) + /// </summary> + public static EqualityComparer<float> BitwiseSingleEqualityComparer { get; } = new BitwiseSingleEqualityComparerImpl(); + + /// <summary> + /// Returns an equality comparer suitable for comparing nullable 64-bit floating point values, by bitwise comparison. + /// (NaN values are considered equal, but only when they have the same representation.) + /// </summary> + public static EqualityComparer<double?> BitwiseNullableDoubleEqualityComparer { get; } = new BitwiseNullableDoubleEqualityComparerImpl(); + + /// <summary> + /// Returns an equality comparer suitable for comparing nullable 32-bit floating point values, by bitwise comparison. + /// (NaN values are considered equal, but only when they have the same representation.) + /// </summary> + public static EqualityComparer<float?> BitwiseNullableSingleEqualityComparer { get; } = new BitwiseNullableSingleEqualityComparerImpl(); + + private class BitwiseDoubleEqualityComparerImpl : EqualityComparer<double> + { + public override bool Equals(double x, double y) => + BitConverter.DoubleToInt64Bits(x) == BitConverter.DoubleToInt64Bits(y); + + public override int GetHashCode(double obj) => + BitConverter.DoubleToInt64Bits(obj).GetHashCode(); + } + + private class BitwiseSingleEqualityComparerImpl : EqualityComparer<float> + { + // Just promote values to double and use BitConverter.DoubleToInt64Bits, + // as there's no BitConverter.SingleToInt32Bits, unfortunately. + + public override bool Equals(float x, float y) => + BitConverter.DoubleToInt64Bits(x) == BitConverter.DoubleToInt64Bits(y); + + public override int GetHashCode(float obj) => + BitConverter.DoubleToInt64Bits(obj).GetHashCode(); + } + + private class BitwiseNullableDoubleEqualityComparerImpl : EqualityComparer<double?> + { + public override bool Equals(double? x, double? y) => + x == null && y == null ? true + : x == null || y == null ? false + : BitwiseDoubleEqualityComparer.Equals(x.Value, y.Value); + + // The hash code for null is just a constant which is at least *unlikely* to be used + // elsewhere. (Compared with 0, say.) + public override int GetHashCode(double? obj) => + obj == null ? 293864 : BitwiseDoubleEqualityComparer.GetHashCode(obj.Value); + } + + private class BitwiseNullableSingleEqualityComparerImpl : EqualityComparer<float?> + { + public override bool Equals(float? x, float? y) => + x == null && y == null ? true + : x == null || y == null ? false + : BitwiseSingleEqualityComparer.Equals(x.Value, y.Value); + + // The hash code for null is just a constant which is at least *unlikely* to be used + // elsewhere. (Compared with 0, say.) + public override int GetHashCode(float? obj) => + obj == null ? 293864 : BitwiseSingleEqualityComparer.GetHashCode(obj.Value); + } + } +} diff --git a/csharp/src/Google.Protobuf/Collections/RepeatedField.cs b/csharp/src/Google.Protobuf/Collections/RepeatedField.cs index 6063ff61..c18b63e2 100755..100644 --- a/csharp/src/Google.Protobuf/Collections/RepeatedField.cs +++ b/csharp/src/Google.Protobuf/Collections/RepeatedField.cs @@ -51,6 +51,7 @@ namespace Google.Protobuf.Collections , IReadOnlyList<T> #endif { + private static readonly EqualityComparer<T> EqualityComparer = ProtobufEqualityComparers.GetEqualityComparer<T>(); private static readonly T[] EmptyArray = new T[0]; private const int MinArraySize = 8; @@ -434,7 +435,7 @@ namespace Google.Protobuf.Collections { return false; } - EqualityComparer<T> comparer = EqualityComparer<T>.Default; + EqualityComparer<T> comparer = EqualityComparer; for (int i = 0; i < count; i++) { if (!comparer.Equals(array[i], other.array[i])) @@ -454,7 +455,7 @@ namespace Google.Protobuf.Collections public int IndexOf(T item) { ProtoPreconditions.CheckNotNullUnconstrained(item, nameof(item)); - EqualityComparer<T> comparer = EqualityComparer<T>.Default; + EqualityComparer<T> comparer = EqualityComparer; for (int i = 0; i < count; i++) { if (comparer.Equals(array[i], item)) |