csharp-sdk-upm/Libs/Google.Protobuf/Reflection/CustomOptions.cs

305 lines
15 KiB
C#

#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 LC.Google.Protobuf.Collections;
using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
namespace LC.Google.Protobuf.Reflection
{
/// <summary>
/// Container for a set of custom options specified within a message, field etc.
/// </summary>
/// <remarks>
/// <para>
/// This type is publicly immutable, but internally mutable. It is only populated
/// by the descriptor parsing code - by the time any user code is able to see an instance,
/// it will be fully initialized.
/// </para>
/// <para>
/// If an option is requested using the incorrect method, an answer may still be returned: all
/// of the numeric types are represented internally using 64-bit integers, for example. It is up to
/// the caller to ensure that they make the appropriate method call for the option they're interested in.
/// Note that enum options are simply stored as integers, so the value should be fetched using
/// <see cref="TryGetInt32(int, out int)"/> and then cast appropriately.
/// </para>
/// <para>
/// Repeated options are currently not supported. Asking for a single value of an option
/// which was actually repeated will return the last value, except for message types where
/// all the set values are merged together.
/// </para>
/// </remarks>
public sealed class CustomOptions
{
private static readonly object[] EmptyParameters = new object[0];
private readonly IDictionary<int, IExtensionValue> values;
internal CustomOptions(IDictionary<int, IExtensionValue> values)
{
this.values = values;
}
/// <summary>
/// Retrieves a Boolean value for the specified option field.
/// </summary>
/// <param name="field">The field to fetch the value for.</param>
/// <param name="value">The output variable to populate.</param>
/// <returns><c>true</c> if a suitable value for the field was found; <c>false</c> otherwise.</returns>
public bool TryGetBool(int field, out bool value) => TryGetPrimitiveValue(field, out value);
/// <summary>
/// Retrieves a signed 32-bit integer value for the specified option field.
/// </summary>
/// <param name="field">The field to fetch the value for.</param>
/// <param name="value">The output variable to populate.</param>
/// <returns><c>true</c> if a suitable value for the field was found; <c>false</c> otherwise.</returns>
public bool TryGetInt32(int field, out int value) => TryGetPrimitiveValue(field, out value);
/// <summary>
/// Retrieves a signed 64-bit integer value for the specified option field.
/// </summary>
/// <param name="field">The field to fetch the value for.</param>
/// <param name="value">The output variable to populate.</param>
/// <returns><c>true</c> if a suitable value for the field was found; <c>false</c> otherwise.</returns>
public bool TryGetInt64(int field, out long value) => TryGetPrimitiveValue(field, out value);
/// <summary>
/// Retrieves an unsigned 32-bit integer value for the specified option field,
/// assuming a fixed-length representation.
/// </summary>
/// <param name="field">The field to fetch the value for.</param>
/// <param name="value">The output variable to populate.</param>
/// <returns><c>true</c> if a suitable value for the field was found; <c>false</c> otherwise.</returns>
public bool TryGetFixed32(int field, out uint value) => TryGetUInt32(field, out value);
/// <summary>
/// Retrieves an unsigned 64-bit integer value for the specified option field,
/// assuming a fixed-length representation.
/// </summary>
/// <param name="field">The field to fetch the value for.</param>
/// <param name="value">The output variable to populate.</param>
/// <returns><c>true</c> if a suitable value for the field was found; <c>false</c> otherwise.</returns>
public bool TryGetFixed64(int field, out ulong value) => TryGetUInt64(field, out value);
/// <summary>
/// Retrieves a signed 32-bit integer value for the specified option field,
/// assuming a fixed-length representation.
/// </summary>
/// <param name="field">The field to fetch the value for.</param>
/// <param name="value">The output variable to populate.</param>
/// <returns><c>true</c> if a suitable value for the field was found; <c>false</c> otherwise.</returns>
public bool TryGetSFixed32(int field, out int value) => TryGetInt32(field, out value);
/// <summary>
/// Retrieves a signed 64-bit integer value for the specified option field,
/// assuming a fixed-length representation.
/// </summary>
/// <param name="field">The field to fetch the value for.</param>
/// <param name="value">The output variable to populate.</param>
/// <returns><c>true</c> if a suitable value for the field was found; <c>false</c> otherwise.</returns>
public bool TryGetSFixed64(int field, out long value) => TryGetInt64(field, out value);
/// <summary>
/// Retrieves a signed 32-bit integer value for the specified option field,
/// assuming a zigzag encoding.
/// </summary>
/// <param name="field">The field to fetch the value for.</param>
/// <param name="value">The output variable to populate.</param>
/// <returns><c>true</c> if a suitable value for the field was found; <c>false</c> otherwise.</returns>
public bool TryGetSInt32(int field, out int value) => TryGetPrimitiveValue(field, out value);
/// <summary>
/// Retrieves a signed 64-bit integer value for the specified option field,
/// assuming a zigzag encoding.
/// </summary>
/// <param name="field">The field to fetch the value for.</param>
/// <param name="value">The output variable to populate.</param>
/// <returns><c>true</c> if a suitable value for the field was found; <c>false</c> otherwise.</returns>
public bool TryGetSInt64(int field, out long value) => TryGetPrimitiveValue(field, out value);
/// <summary>
/// Retrieves an unsigned 32-bit integer value for the specified option field.
/// </summary>
/// <param name="field">The field to fetch the value for.</param>
/// <param name="value">The output variable to populate.</param>
/// <returns><c>true</c> if a suitable value for the field was found; <c>false</c> otherwise.</returns>
public bool TryGetUInt32(int field, out uint value) => TryGetPrimitiveValue(field, out value);
/// <summary>
/// Retrieves an unsigned 64-bit integer value for the specified option field.
/// </summary>
/// <param name="field">The field to fetch the value for.</param>
/// <param name="value">The output variable to populate.</param>
/// <returns><c>true</c> if a suitable value for the field was found; <c>false</c> otherwise.</returns>
public bool TryGetUInt64(int field, out ulong value) => TryGetPrimitiveValue(field, out value);
/// <summary>
/// Retrieves a 32-bit floating point value for the specified option field.
/// </summary>
/// <param name="field">The field to fetch the value for.</param>
/// <param name="value">The output variable to populate.</param>
/// <returns><c>true</c> if a suitable value for the field was found; <c>false</c> otherwise.</returns>
public bool TryGetFloat(int field, out float value) => TryGetPrimitiveValue(field, out value);
/// <summary>
/// Retrieves a 64-bit floating point value for the specified option field.
/// </summary>
/// <param name="field">The field to fetch the value for.</param>
/// <param name="value">The output variable to populate.</param>
/// <returns><c>true</c> if a suitable value for the field was found; <c>false</c> otherwise.</returns>
public bool TryGetDouble(int field, out double value) => TryGetPrimitiveValue(field, out value);
/// <summary>
/// Retrieves a string value for the specified option field.
/// </summary>
/// <param name="field">The field to fetch the value for.</param>
/// <param name="value">The output variable to populate.</param>
/// <returns><c>true</c> if a suitable value for the field was found; <c>false</c> otherwise.</returns>
public bool TryGetString(int field, out string value) => TryGetPrimitiveValue(field, out value);
/// <summary>
/// Retrieves a bytes value for the specified option field.
/// </summary>
/// <param name="field">The field to fetch the value for.</param>
/// <param name="value">The output variable to populate.</param>
/// <returns><c>true</c> if a suitable value for the field was found; <c>false</c> otherwise.</returns>
public bool TryGetBytes(int field, out ByteString value) => TryGetPrimitiveValue(field, out value);
/// <summary>
/// Retrieves a message value for the specified option field.
/// </summary>
/// <param name="field">The field to fetch the value for.</param>
/// <param name="value">The output variable to populate.</param>
/// <returns><c>true</c> if a suitable value for the field was found; <c>false</c> otherwise.</returns>
public bool TryGetMessage<T>(int field, out T value) where T : class, IMessage, new()
{
if (values == null)
{
value = default(T);
return false;
}
IExtensionValue extensionValue;
if (values.TryGetValue(field, out extensionValue))
{
if (extensionValue is ExtensionValue<T>)
{
ExtensionValue<T> single = extensionValue as ExtensionValue<T>;
ByteString bytes = single.GetValue().ToByteString();
value = new T();
value.MergeFrom(bytes);
return true;
}
else if (extensionValue is RepeatedExtensionValue<T>)
{
RepeatedExtensionValue<T> repeated = extensionValue as RepeatedExtensionValue<T>;
value = repeated.GetValue()
.Select(v => v.ToByteString())
.Aggregate(new T(), (t, b) =>
{
t.MergeFrom(b);
return t;
});
return true;
}
}
value = null;
return false;
}
private bool TryGetPrimitiveValue<T>(int field, out T value)
{
if (values == null)
{
value = default(T);
return false;
}
IExtensionValue extensionValue;
if (values.TryGetValue(field, out extensionValue))
{
if (extensionValue is ExtensionValue<T>)
{
ExtensionValue<T> single = extensionValue as ExtensionValue<T>;
value = single.GetValue();
return true;
}
else if (extensionValue is RepeatedExtensionValue<T>)
{
RepeatedExtensionValue<T> repeated = extensionValue as RepeatedExtensionValue<T>;
if (repeated.GetValue().Count != 0)
{
RepeatedField<T> repeatedField = repeated.GetValue();
value = repeatedField[repeatedField.Count - 1];
return true;
}
}
else // and here we find explicit enum handling since T : Enum ! x is ExtensionValue<Enum>
{
var type = extensionValue.GetType();
if (type.GetGenericTypeDefinition() == typeof(ExtensionValue<>))
{
var typeInfo = type.GetTypeInfo();
var typeArgs = typeInfo.GenericTypeArguments;
if (typeArgs.Length == 1 && typeArgs[0].GetTypeInfo().IsEnum)
{
value = (T)typeInfo.GetDeclaredMethod(nameof(ExtensionValue<T>.GetValue)).Invoke(extensionValue, EmptyParameters);
return true;
}
}
else if (type.GetGenericTypeDefinition() == typeof(RepeatedExtensionValue<>))
{
var typeInfo = type.GetTypeInfo();
var typeArgs = typeInfo.GenericTypeArguments;
if (typeArgs.Length == 1 && typeArgs[0].GetTypeInfo().IsEnum)
{
var values = (IList)typeInfo.GetDeclaredMethod(nameof(RepeatedExtensionValue<T>.GetValue)).Invoke(extensionValue, EmptyParameters);
if (values.Count != 0)
{
value = (T)values[values.Count - 1];
return true;
}
}
}
}
}
value = default(T);
return false;
}
}
}