csharp/src/Google.Protobuf/Reflection/DescriptorPool.cs - third_party/protobuf - Git at Google

 #region Copyright notice and license
 // Protocol Buffers - Google's data interchange format
 // Copyright 2008 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;
 using System.Text;
 using System.Text.RegularExpressions;

 namespace Google.Protobuf.Reflection
 {
     /// <summary>
     /// Contains lookup tables containing all the descriptors defined in a particular file.
     /// </summary>
     internal sealed class DescriptorPool
     {
         private readonly IDictionary<string, IDescriptor> descriptorsByName =
             new Dictionary<string, IDescriptor>();

         private readonly IDictionary<ObjectIntPair<IDescriptor>, FieldDescriptor> fieldsByNumber =
             new Dictionary<ObjectIntPair<IDescriptor>, FieldDescriptor>();

         private readonly IDictionary<ObjectIntPair<IDescriptor>, EnumValueDescriptor> enumValuesByNumber =
             new Dictionary<ObjectIntPair<IDescriptor>, EnumValueDescriptor>();

         private readonly HashSet<FileDescriptor> dependencies = new HashSet<FileDescriptor>();

         internal DescriptorPool(IEnumerable<FileDescriptor> dependencyFiles)
         {
             foreach (FileDescriptor dependencyFile in dependencyFiles)
             {
                 dependencies.Add(dependencyFile);
                 ImportPublicDependencies(dependencyFile);
             }

             foreach (FileDescriptor dependency in dependencyFiles)
             {
                 AddPackage(dependency.Package, dependency);
             }
         }

         private void ImportPublicDependencies(FileDescriptor file)
         {
             foreach (FileDescriptor dependency in file.PublicDependencies)
             {
                 if (dependencies.Add(dependency))
                 {
                     ImportPublicDependencies(dependency);
                 }
             }
         }

         /// <summary>
         /// Finds a symbol of the given name within the pool.
         /// </summary>
         /// <typeparam name="T">The type of symbol to look for</typeparam>
         /// <param name="fullName">Fully-qualified name to look up</param>
         /// <returns>The symbol with the given name and type,
         /// or null if the symbol doesn't exist or has the wrong type</returns>
         internal T FindSymbol<T>(string fullName) where T : class
         {
             descriptorsByName.TryGetValue(fullName, out IDescriptor result);
             if (result is T descriptor)
             {
                 return descriptor;
             }

             // dependencies contains direct dependencies and any *public* dependencies
             // of those dependencies (transitively)... so we don't need to recurse here.
             foreach (FileDescriptor dependency in dependencies)
             {
                 dependency.DescriptorPool.descriptorsByName.TryGetValue(fullName, out result);
                 descriptor = result as T;
                 if (descriptor != null)
                 {
                     return descriptor;
                 }
             }

             return null;
         }

         /// <summary>
         /// Adds a package to the symbol tables. If a package by the same name
         /// already exists, that is fine, but if some other kind of symbol
         /// exists under the same name, an exception is thrown. If the package
         /// has multiple components, this also adds the parent package(s).
         /// </summary>
         internal void AddPackage(string fullName, FileDescriptor file)
         {
             int dotpos = fullName.LastIndexOf('.');
             String name;
             if (dotpos != -1)
             {
                 AddPackage(fullName.Substring(0, dotpos), file);
                 name = fullName.Substring(dotpos + 1);
             }
             else
             {
                 name = fullName;
             }

             if (descriptorsByName.TryGetValue(fullName, out IDescriptor old))
             {
                 if (old is not PackageDescriptor)
                 {
                     throw new DescriptorValidationException(file,
                                                             "\"" + name +
                                                             "\" is already defined (as something other than a " +
                                                             "package) in file \"" + old.File.Name + "\".");
                 }
             }
             descriptorsByName[fullName] = new PackageDescriptor(name, fullName, file);
         }

         /// <summary>
         /// Adds a symbol to the symbol table.
         /// </summary>
         /// <exception cref="DescriptorValidationException">The symbol already existed
         /// in the symbol table.</exception>
         internal void AddSymbol(IDescriptor descriptor)
         {
             ValidateSymbolName(descriptor);
             string fullName = descriptor.FullName;

             if (descriptorsByName.TryGetValue(fullName, out IDescriptor old))
             {
                 int dotPos = fullName.LastIndexOf('.');
                 string message;
                 if (descriptor.File == old.File)
                 {
                     if (dotPos == -1)
                     {
                         message = "\"" + fullName + "\" is already defined.";
                     }
                     else
                     {
                         message = "\"" + fullName.Substring(dotPos + 1) + "\" is already defined in \"" +
                                   fullName.Substring(0, dotPos) + "\".";
                     }
                 }
                 else
                 {
                     message = "\"" + fullName + "\" is already defined in file \"" + old.File.Name + "\".";
                 }
                 throw new DescriptorValidationException(descriptor, message);
             }
             descriptorsByName[fullName] = descriptor;
         }

         private static readonly Regex ValidationRegex = new Regex("^[_A-Za-z][_A-Za-z0-9]*$", FrameworkPortability.CompiledRegexWhereAvailable);

         /// <summary>
         /// Verifies that the descriptor's name is valid (i.e. it contains
         /// only letters, digits and underscores, and does not start with a digit).
         /// </summary>
         /// <param name="descriptor"></param>
         private static void ValidateSymbolName(IDescriptor descriptor)
         {
             if (descriptor.Name.Length == 0)
             {
                 throw new DescriptorValidationException(descriptor, "Missing name.");
             }
             if (!ValidationRegex.IsMatch(descriptor.Name))
             {
                 throw new DescriptorValidationException(descriptor,
                                                         "\"" + descriptor.Name + "\" is not a valid identifier.");
             }
         }

         /// <summary>
         /// Returns the field with the given number in the given descriptor,
         /// or null if it can't be found.
         /// </summary>
         internal FieldDescriptor FindFieldByNumber(MessageDescriptor messageDescriptor, int number)
         {
             fieldsByNumber.TryGetValue(new ObjectIntPair<IDescriptor>(messageDescriptor, number), out FieldDescriptor ret);
             return ret;
         }

         internal EnumValueDescriptor FindEnumValueByNumber(EnumDescriptor enumDescriptor, int number)
         {
             enumValuesByNumber.TryGetValue(new ObjectIntPair<IDescriptor>(enumDescriptor, number), out EnumValueDescriptor ret);
             return ret;
         }

         /// <summary>
         /// Adds a field to the fieldsByNumber table.
         /// </summary>
         /// <exception cref="DescriptorValidationException">A field with the same
         /// containing type and number already exists.</exception>
         internal void AddFieldByNumber(FieldDescriptor field)
         {
             // for extensions, we use the extended type, otherwise we use the containing type
             ObjectIntPair<IDescriptor> key = new ObjectIntPair<IDescriptor>(field.Proto.HasExtendee ? field.ExtendeeType : field.ContainingType, field.FieldNumber);
             if (fieldsByNumber.TryGetValue(key, out FieldDescriptor old))
             {
                 throw new DescriptorValidationException(field, "Field number " + field.FieldNumber +
                                                                "has already been used in \"" +
                                                                field.ContainingType.FullName +
                                                                "\" by field \"" + old.Name + "\".");
             }
             fieldsByNumber[key] = field;
         }

         /// <summary>
         /// Adds an enum value to the enumValuesByNumber table. If an enum value
         /// with the same type and number already exists, this method does nothing.
         /// (This is allowed; the first value defined with the number takes precedence.)
         /// </summary>
         internal void AddEnumValueByNumber(EnumValueDescriptor enumValue)
         {
             ObjectIntPair<IDescriptor> key = new ObjectIntPair<IDescriptor>(enumValue.EnumDescriptor, enumValue.Number);
             if (!enumValuesByNumber.ContainsKey(key))
             {
                 enumValuesByNumber[key] = enumValue;
             }
         }

         /// <summary>
         /// Looks up a descriptor by name, relative to some other descriptor.
         /// The name may be fully-qualified (with a leading '.'), partially-qualified,
         /// or unqualified. C++-like name lookup semantics are used to search for the
         /// matching descriptor.
         /// </summary>
         /// <remarks>
         /// This isn't heavily optimized, but it's only used during cross linking anyway.
         /// If it starts being used more widely, we should look at performance more carefully.
         /// </remarks>
         internal IDescriptor LookupSymbol(string name, IDescriptor relativeTo)
         {
             IDescriptor result;
             if (name.StartsWith("."))
             {
                 // Fully-qualified name.
                 result = FindSymbol<IDescriptor>(name.Substring(1));
             }
             else
             {
                 // If "name" is a compound identifier, we want to search for the
                 // first component of it, then search within it for the rest.
                 int firstPartLength = name.IndexOf('.');
                 string firstPart = firstPartLength == -1 ? name : name.Substring(0, firstPartLength);

                 // We will search each parent scope of "relativeTo" looking for the
                 // symbol.
                 StringBuilder scopeToTry = new StringBuilder(relativeTo.FullName);

                 while (true)
                 {
                     // Chop off the last component of the scope.

                     int dotpos = scopeToTry.ToString().LastIndexOf(".");
                     if (dotpos == -1)
                     {
                         result = FindSymbol<IDescriptor>(name);
                         break;
                     }
                     else
                     {
                         scopeToTry.Length = dotpos + 1;

                         // Append firstPart and try to find.
                         scopeToTry.Append(firstPart);
                         result = FindSymbol<IDescriptor>(scopeToTry.ToString());

                         if (result != null)
                         {
                             if (firstPartLength != -1)
                             {
                                 // We only found the first part of the symbol.  Now look for
                                 // the whole thing.  If this fails, we *don't* want to keep
                                 // searching parent scopes.
                                 scopeToTry.Length = dotpos + 1;
                                 scopeToTry.Append(name);
                                 result = FindSymbol<IDescriptor>(scopeToTry.ToString());
                             }
                             break;
                         }

                         // Not found.  Remove the name so we can try again.
                         scopeToTry.Length = dotpos;
                     }
                 }
             }

             if (result == null)
             {
                 throw new DescriptorValidationException(relativeTo, "\"" + name + "\" is not defined.");
             }
             else
             {
                 return result;
             }
         }
     }
 }
	#region Copyright notice and license
	// Protocol Buffers - Google's data interchange format
	// Copyright 2008 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;
	using System.Text;
	using System.Text.RegularExpressions;

	namespace Google.Protobuf.Reflection
	{
	/// <summary>
	/// Contains lookup tables containing all the descriptors defined in a particular file.
	/// </summary>
	internal sealed class DescriptorPool
	{
	private readonly IDictionary<string, IDescriptor> descriptorsByName =
	new Dictionary<string, IDescriptor>();

	private readonly IDictionary<ObjectIntPair<IDescriptor>, FieldDescriptor> fieldsByNumber =
	new Dictionary<ObjectIntPair<IDescriptor>, FieldDescriptor>();

	private readonly IDictionary<ObjectIntPair<IDescriptor>, EnumValueDescriptor> enumValuesByNumber =
	new Dictionary<ObjectIntPair<IDescriptor>, EnumValueDescriptor>();

	private readonly HashSet<FileDescriptor> dependencies = new HashSet<FileDescriptor>();

	internal DescriptorPool(IEnumerable<FileDescriptor> dependencyFiles)
	{
	foreach (FileDescriptor dependencyFile in dependencyFiles)
	{
	dependencies.Add(dependencyFile);
	ImportPublicDependencies(dependencyFile);
	}

	foreach (FileDescriptor dependency in dependencyFiles)
	{
	AddPackage(dependency.Package, dependency);
	}
	}

	private void ImportPublicDependencies(FileDescriptor file)
	{
	foreach (FileDescriptor dependency in file.PublicDependencies)
	{
	if (dependencies.Add(dependency))
	{
	ImportPublicDependencies(dependency);
	}
	}
	}

	/// <summary>
	/// Finds a symbol of the given name within the pool.
	/// </summary>
	/// <typeparam name="T">The type of symbol to look for</typeparam>
	/// <param name="fullName">Fully-qualified name to look up</param>
	/// <returns>The symbol with the given name and type,
	/// or null if the symbol doesn't exist or has the wrong type</returns>
	internal T FindSymbol<T>(string fullName) where T : class
	{
	descriptorsByName.TryGetValue(fullName, out IDescriptor result);
	if (result is T descriptor)
	{
	return descriptor;
	}

	// dependencies contains direct dependencies and any public dependencies
	// of those dependencies (transitively)... so we don't need to recurse here.
	foreach (FileDescriptor dependency in dependencies)
	{
	dependency.DescriptorPool.descriptorsByName.TryGetValue(fullName, out result);
	descriptor = result as T;
	if (descriptor != null)
	{
	return descriptor;
	}
	}

	return null;
	}

	/// <summary>
	/// Adds a package to the symbol tables. If a package by the same name
	/// already exists, that is fine, but if some other kind of symbol
	/// exists under the same name, an exception is thrown. If the package
	/// has multiple components, this also adds the parent package(s).
	/// </summary>
	internal void AddPackage(string fullName, FileDescriptor file)
	{
	int dotpos = fullName.LastIndexOf('.');
	String name;
	if (dotpos != -1)
	{
	AddPackage(fullName.Substring(0, dotpos), file);
	name = fullName.Substring(dotpos + 1);
	}
	else
	{
	name = fullName;
	}

	if (descriptorsByName.TryGetValue(fullName, out IDescriptor old))
	{
	if (old is not PackageDescriptor)
	{
	throw new DescriptorValidationException(file,
	"\"" + name +
	"\" is already defined (as something other than a " +
	"package) in file \"" + old.File.Name + "\".");
	}
	}
	descriptorsByName[fullName] = new PackageDescriptor(name, fullName, file);
	}

	/// <summary>
	/// Adds a symbol to the symbol table.
	/// </summary>
	/// <exception cref="DescriptorValidationException">The symbol already existed
	/// in the symbol table.</exception>
	internal void AddSymbol(IDescriptor descriptor)
	{
	ValidateSymbolName(descriptor);
	string fullName = descriptor.FullName;

	if (descriptorsByName.TryGetValue(fullName, out IDescriptor old))
	{
	int dotPos = fullName.LastIndexOf('.');
	string message;
	if (descriptor.File == old.File)
	{
	if (dotPos == -1)
	{
	message = "\"" + fullName + "\" is already defined.";
	}
	else
	{
	message = "\"" + fullName.Substring(dotPos + 1) + "\" is already defined in \"" +
	fullName.Substring(0, dotPos) + "\".";
	}
	}
	else
	{
	message = "\"" + fullName + "\" is already defined in file \"" + old.File.Name + "\".";
	}
	throw new DescriptorValidationException(descriptor, message);
	}
	descriptorsByName[fullName] = descriptor;
	}

	private static readonly Regex ValidationRegex = new Regex("^[_A-Za-z][_A-Za-z0-9]*$", FrameworkPortability.CompiledRegexWhereAvailable);

	/// <summary>
	/// Verifies that the descriptor's name is valid (i.e. it contains
	/// only letters, digits and underscores, and does not start with a digit).
	/// </summary>
	/// <param name="descriptor"></param>
	private static void ValidateSymbolName(IDescriptor descriptor)
	{
	if (descriptor.Name.Length == 0)
	{
	throw new DescriptorValidationException(descriptor, "Missing name.");
	}
	if (!ValidationRegex.IsMatch(descriptor.Name))
	{
	throw new DescriptorValidationException(descriptor,
	"\"" + descriptor.Name + "\" is not a valid identifier.");
	}
	}

	/// <summary>
	/// Returns the field with the given number in the given descriptor,
	/// or null if it can't be found.
	/// </summary>
	internal FieldDescriptor FindFieldByNumber(MessageDescriptor messageDescriptor, int number)
	{
	fieldsByNumber.TryGetValue(new ObjectIntPair<IDescriptor>(messageDescriptor, number), out FieldDescriptor ret);
	return ret;
	}

	internal EnumValueDescriptor FindEnumValueByNumber(EnumDescriptor enumDescriptor, int number)
	{
	enumValuesByNumber.TryGetValue(new ObjectIntPair<IDescriptor>(enumDescriptor, number), out EnumValueDescriptor ret);
	return ret;
	}

	/// <summary>
	/// Adds a field to the fieldsByNumber table.
	/// </summary>
	/// <exception cref="DescriptorValidationException">A field with the same
	/// containing type and number already exists.</exception>
	internal void AddFieldByNumber(FieldDescriptor field)
	{
	// for extensions, we use the extended type, otherwise we use the containing type
	ObjectIntPair<IDescriptor> key = new ObjectIntPair<IDescriptor>(field.Proto.HasExtendee ? field.ExtendeeType : field.ContainingType, field.FieldNumber);
	if (fieldsByNumber.TryGetValue(key, out FieldDescriptor old))
	{
	throw new DescriptorValidationException(field, "Field number " + field.FieldNumber +
	"has already been used in \"" +
	field.ContainingType.FullName +
	"\" by field \"" + old.Name + "\".");
	}
	fieldsByNumber[key] = field;
	}

	/// <summary>
	/// Adds an enum value to the enumValuesByNumber table. If an enum value
	/// with the same type and number already exists, this method does nothing.
	/// (This is allowed; the first value defined with the number takes precedence.)
	/// </summary>
	internal void AddEnumValueByNumber(EnumValueDescriptor enumValue)
	{
	ObjectIntPair<IDescriptor> key = new ObjectIntPair<IDescriptor>(enumValue.EnumDescriptor, enumValue.Number);
	if (!enumValuesByNumber.ContainsKey(key))
	{
	enumValuesByNumber[key] = enumValue;
	}
	}

	/// <summary>
	/// Looks up a descriptor by name, relative to some other descriptor.
	/// The name may be fully-qualified (with a leading '.'), partially-qualified,
	/// or unqualified. C++-like name lookup semantics are used to search for the
	/// matching descriptor.
	/// </summary>
	/// <remarks>
	/// This isn't heavily optimized, but it's only used during cross linking anyway.
	/// If it starts being used more widely, we should look at performance more carefully.
	/// </remarks>
	internal IDescriptor LookupSymbol(string name, IDescriptor relativeTo)
	{
	IDescriptor result;
	if (name.StartsWith("."))
	{
	// Fully-qualified name.
	result = FindSymbol<IDescriptor>(name.Substring(1));
	}
	else
	{
	// If "name" is a compound identifier, we want to search for the
	// first component of it, then search within it for the rest.
	int firstPartLength = name.IndexOf('.');
	string firstPart = firstPartLength == -1 ? name : name.Substring(0, firstPartLength);

	// We will search each parent scope of "relativeTo" looking for the
	// symbol.
	StringBuilder scopeToTry = new StringBuilder(relativeTo.FullName);

	while (true)
	{
	// Chop off the last component of the scope.

	int dotpos = scopeToTry.ToString().LastIndexOf(".");
	if (dotpos == -1)
	{
	result = FindSymbol<IDescriptor>(name);
	break;
	}
	else
	{
	scopeToTry.Length = dotpos + 1;

	// Append firstPart and try to find.
	scopeToTry.Append(firstPart);
	result = FindSymbol<IDescriptor>(scopeToTry.ToString());

	if (result != null)
	{
	if (firstPartLength != -1)
	{
	// We only found the first part of the symbol. Now look for
	// the whole thing. If this fails, we don't want to keep
	// searching parent scopes.
	scopeToTry.Length = dotpos + 1;
	scopeToTry.Append(name);
	result = FindSymbol<IDescriptor>(scopeToTry.ToString());
	}
	break;
	}

	// Not found. Remove the name so we can try again.
	scopeToTry.Length = dotpos;
	}
	}
	}

	if (result == null)
	{
	throw new DescriptorValidationException(relativeTo, "\"" + name + "\" is not defined.");
	}
	else
	{
	return result;
	}
	}
	}
	}